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Qian Y, Zhang Y, Huang J, Liu J, Chen G, Xia G, Wang C, Feng A, Chen Y, Chen J, Zeng Y, Nie X. Risk Factors for Pneumocystis jirovecii Pneumonia in Children With Systemic Lupus Erythematosus Exposed to Prolonged High-Dose Glucocorticoids. J Clin Rheumatol 2024:00124743-990000000-00189. [PMID: 38389131 DOI: 10.1097/rhu.0000000000002073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
BACKGROUND Pneumocystis jirovecii pneumonia (PJP) is a life-threatening opportunistic infection in immunocompromised children with systemic lupus erythematosus (SLE). Prophylaxis against PJP in high-risk children is crucial, but the risk factors for PJP in children with SLE are not adequately characterized. This study sought to identify the risk factors for PJP in long-term glucocorticoid-treated pediatric SLE patients. METHODS This study encompassed 71 treatment episodes involving 64 children with prolonged (≥4 weeks) high-dose (≥20 mg/d prednisone) steroid regimens. Fourteen treatment episodes involved the PJP, whereas others did not. Risk factors for PJP were assessed through Cox regression. The predictive value of these factors was evaluated using receiver operating characteristic curves. The incidence of PJP in different risk groups was compared using the Kaplan-Meier method. RESULTS The creatinine (hazard ratio, 1.009; 95% confidence interval [CI], 1.001-1.017; p = 0.021) and the lowest lymphocyte count (hazard ratio, 0.007; 95% CI, 0.000-0.373; p = 0.014) were independent risk factors for PJP in children with SLE. The receiver operating characteristic curve showed that using creatinine greater than 72.5 μmol/L and the lowest lymphocyte count less than 0.6 × 109/L as risk predictors for PJP resulted in an area under the curve value of 0.934 (95% CI, 0.870-0.997; p < 0.001). The study revealed a significant increase in PJP prevalence (p < 0.001) in children with elevated creatinine levels and low lymphocyte count. CONCLUSIONS Elevated levels of creatinine and decreased lymphocyte count are identified as distinct risk factors for PJP in children with SLE who receive prolonged high-dose steroid therapy.
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Affiliation(s)
| | | | | | - Jingjing Liu
- Department of Pediatrics, The 900th Hospital of the Joint Logistic Support Force, Fuzhou, China
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Sassi M, Curran SJ, Bishop LR, Liu Y, Kovacs JA. CD40 Expression by B cells is Required for Optimal Immunity to Murine Pneumocystis Infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.578900. [PMID: 38410485 PMCID: PMC10896351 DOI: 10.1101/2024.02.05.578900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
CD40-CD40L interactions are critical for controlling Pneumocystis infection. However, which CD40-expressing cell populations are important for this interaction have not been well-defined. We used a cohousing mouse model of Pneumocystis infection, combined with flow cytometry and qPCR, to examine the ability of different populations of cells from C57BL/6 mice to reconstitute immunity in CD40 knockout (KO) mice. Unfractionated splenocytes, as well as purified B cells, were able to control Pneumocystis infection, while B cell depleted splenocytes and unstimulated bone-marrow derived dendritic cells (BMDCs) were unable to control infection in CD40 KO mice. Pneumocystis antigen-pulsed BMDCs showed early, but limited, control of infection. Consistent with recent studies that have suggested a role for antigen presentation by B cells, using cells from immunized animals, B cells were able to present Pneumocystis antigens to induce proliferation of T cells. Thus, CD40 expression by B cells appears necessary for robust immunity to Pneumocystis.
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Affiliation(s)
- Monica Sassi
- Critical Care Medicine Department, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland 20892 USA
| | - Shelly J Curran
- Critical Care Medicine Department, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland 20892 USA
| | - Lisa R Bishop
- Critical Care Medicine Department, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland 20892 USA
| | - Yueqin Liu
- Critical Care Medicine Department, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland 20892 USA
| | - Joseph A Kovacs
- Critical Care Medicine Department, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland 20892 USA
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3
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Trubin PA, Azar MM. Current Concepts in the Diagnosis and Management of Pneumocystis Pneumonia in Solid Organ Transplantation. Infect Dis Clin North Am 2023:S0891-5520(23)00026-0. [PMID: 37142510 DOI: 10.1016/j.idc.2023.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Pneumocystis infection manifests predominantly as an interstitial pneumonia in immunocompromised patients. Diagnostic testing in the appropriate clinical context can be highly sensitive and specific and involves radiographic imaging, fungal biomarkers, nucleic acid amplification, histopathology, and lung fluid or tissue sampling. Trimethoprim-sulfamethoxazole remains the first-choice agent for treatment and prophylaxis. Investigation continues to promote a deeper understanding of the pathogen's ecology, epidemiology, host susceptibility, and optimal treatment and prevention strategies in solid organ transplant recipients.
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Affiliation(s)
- Paul A Trubin
- Department of Medicine, Section of Infectious Diseases, Yale School of Medicine, 135 College Street, New Haven, CT 06510, USA.
| | - Marwan M Azar
- Department of Medicine, Section of Infectious Diseases; Department of Laboratory Medicine; Yale School of Medicine, 135 College Street, New Haven, CT 06510, USA
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Zhang ZQ, Gigliotti F, Wright TW. The Dual Benefit of Sulfasalazine on Pneumocystis Pneumonia-Related Immunopathogenesis and Antifungal Host Defense Does Not Require IL-4Rα-Dependent Macrophage Polarization. Infect Immun 2023; 91:e0049022. [PMID: 36916933 PMCID: PMC10112227 DOI: 10.1128/iai.00490-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 02/22/2023] [Indexed: 03/16/2023] Open
Abstract
Pneumocystis is a respiratory fungal pathogen that is among the most frequent causes of life-threatening pneumonia (PcP) in immunocompromised hosts. Alveolar macrophages play an important role in host defense against Pneumocystis, and several studies have suggested that M2 polarized macrophages have anti-Pneumocystis effector activity. Our prior work found that the immunomodulatory drug sulfasalazine (SSZ) provides a dual benefit during PcP-related immune reconstitution inflammatory syndrome (IRIS) by concurrently suppressing immunopathogenesis while also accelerating macrophage-mediated fungal clearance. The benefits of SSZ were associated with heightened Th2 cytokine production and M2 macrophage polarization. Therefore, to determine whether SSZ improves the outcome of PcP through a mechanism that requires Th2-dependent M2 polarization, RAG2-/- mice lacking interleukin 4 receptor alpha chain (IL-4Rα) on macrophage lineage cells were generated. As expected, SSZ treatment dramatically reduced the severity of PcP-related immunopathogenesis and accelerated fungal clearance in immune-reconstituted RAG2-/- mice. Similarly, SSZ treatment was also highly effective in immune-reconstituted RAG2/IL-4Rα-/- and RAG2/gamma interferon receptor (IFN-γR)-/- mice, demonstrating that neither IL-4Rα-dependent M2 nor IFN-γR-dependent M1 macrophage polarization programs were required for the beneficial effects of SSZ. Despite the fact that macrophages from RAG2/IL-4Rα-/- mice could not respond to the Th2 cytokines IL-4 and IL-13, M2-biased alveolar macrophages were identified in the lungs following SSZ treatment. These data demonstrate that not only does SSZ enhance phagocytosis and fungal clearance in the absence of macrophage IL-4Rα signaling, but also that SSZ promotes M2 macrophage polarization in an IL-4Rα-independent manner. These findings could have implications for the treatment of PcP and other diseases in which M2 polarization is beneficial.
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Affiliation(s)
- Zhuo-Qian Zhang
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Francis Gigliotti
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
- Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Terry W. Wright
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
- Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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5
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Rong HM, Kang HYJ, Tong ZH. Metabolomic Profiling of Lungs from Mice Reveals the Variability of Metabolites in Pneumocystis Infection and the Metabolic Abnormalities in BAFF-R-Deficient Mice. J Inflamm Res 2023; 16:1357-1373. [PMID: 37006807 PMCID: PMC10065423 DOI: 10.2147/jir.s394608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 03/14/2023] [Indexed: 03/29/2023] Open
Abstract
Purpose The incidence of Pneumocystis pneumonia (PCP) in patients without human immunodeficiency virus (HIV) has been increasing. In this study, we aimed to investigate the metabolic changes in Pneumocystis infection and the metabolic abnormalities in B-cell-activating factor receptor (BAFF-R)-deficient mice with Pneumocystis infection. Methods The important function of B cells during Pneumocystis infection is increasingly recognized. In this study, a Pneumocystis-infected mouse model was constructed in BAFF-R-/- mice and wild-type (WT) mice. Lungs of uninfected WT C57BL/6, WT Pneumocystis-infected, and BAFF-R-/- Pneumocystis-infected mice were used for metabolomic analyses to compare the metabolomic profiles among the groups, with the aim of exploring the metabolic influence of Pneumocystis infection and the influence of mature B-cell deficiency during infection. Results The results indicated that many metabolites, mainly lipids and lipid-like molecules, were dysregulated in Pneumocystis-infected WT mice compared with uninfected WT C57BL/6 mice. The data also demonstrated significant changes in tryptophan metabolism, and the expression levels of key enzymes of tryptophan metabolism, such as indoleamine 2,3-dioxygenase 1 (IDO1), were significantly upregulated. In addition, B-cell development and function might be associated with lipid metabolism. We found a lower level of alitretinoin and the abnormalities of fatty acid metabolism in BAFF-R-/- Pneumocystis-infected mice. The mRNA levels of enzymes associated with fatty acid metabolism in the lung were upregulated in BAFF-R-/- Pneumocystis-infected mice and positively correlated with the level of IL17A, thus suggesting that the abnormalities of fatty acid metabolism may be associated with greater inflammatory cell infiltration in the lung tissue of BAFF-R-/- Pneumocystis-infected mice compared with the WT Pneumocystis-infected mice. Conclusion Our data revealed the variability of metabolites in Pneumocystis-infected mice, suggesting that the metabolism plays a vital role in the immune response to Pneumocystis infection.
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Affiliation(s)
- Heng-Mo Rong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, People’s Republic of China
| | - Han-Yu-Jie Kang
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, People’s Republic of China
| | - Zhao-Hui Tong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, People’s Republic of China
- Correspondence: Zhao-Hui Tong, Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, NO. 8, Gong Ti South Road, Chao yang District, Beijing, 100020, People’s Republic of China, Tel +86 13910930309, Email
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Abstract
Pneumocystis jirovecii causes pneumonia in immunocompromised patients. A major challenge in drug susceptibility testing and in understanding host/pathogen interactions is that Pneumocystis spp. are not viable in vitro. Continuous culture of the organism is not currently available, and therefore, developing new drug targets is very limited. Due to this limitation, mouse models of Pneumocystis pneumonia have proven to be an invaluable resource to researchers. In this chapter, we provide an overview of selected methods used in mouse models of infection including, in vivo Pneumocystis murina propagation, routes of transmission, genetic mouse models available, a P. murina life form-specific model, a mouse model of PCP immune reconstitution inflammatory syndrome (IRIS), and the experimental parameters associated with these models.
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Affiliation(s)
- J Claire Hoving
- AFRICA CMM Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine (IDM), Cape Town, South Africa.
- Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
- MRC Centre for Medical Mycology, University of Exeter, Exeter, UK.
| | - Ferris T Munyonho
- Centre for Translational Research in Infection and Inflammation, Tulane School of Medicine, New Orleans, LA, USA
| | - Jay K Kolls
- Centre for Translational Research in Infection and Inflammation, Tulane School of Medicine, New Orleans, LA, USA.
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Noell K, Dai G, Pungan D, Ebacher A, McCombs JE, Landry SJ, Kolls JK. Germline IgM predicts T-cell immunity to Pneumocystis. JCI Insight 2022; 7:161450. [PMID: 35917185 PMCID: PMC9536272 DOI: 10.1172/jci.insight.161450] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 07/28/2022] [Indexed: 11/17/2022] Open
Abstract
Pneumocystis is the most common fungal pulmonary infection in children under 5. In children with primary immunodeficiency, Pneumocystis often presents at 3-6 months that coincides with the nadir of maternal IgG and where IgM is the dominant immunoglobulin isotype. Since B cells are the dominant antigen-presenting cells for Pneumocystis, we hypothesized the presence of fungal specific IgMs in human and mice and that these IgM specificities would predict T cell antigens. We detected fungal specific IgMs in human and mouse serum and utilized immunoprecipitation to determine if any antigens were similar across donors. We then assessed T cell responses to these antigens. We found anti-Pneumocystis IgM in wild-type mice as well as Aicda-/- mice and in human cord blood. Immunoprecipitation of Pneumocystis murina with human cord blood identified shared antigens among these donors. Using class II MHC binding prediction, we designed peptides with these antigens and identified robust peptide specific lung T cell responses after P. murina infection. After mice were immunized with two of the antigens, adoptive transfer of vaccine elicited CD4+ T cells showed effector activity suggesting that these antigens contain protective Pneumocystis epitopes. These data support the notion that germline encoded IgM B-cell receptors are critical in antigen presentation and T cell priming in early Pneumocystis infection.
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Affiliation(s)
- Kristin Noell
- Departments of Pediatrics & Medicine, Tulane University School of Medicine, New Orleans, United States of America
| | - Guixiang Dai
- Departments of Pediatrics & Medicine, Tulane University School of Medicine, New Orleans, United States of America
| | - Dora Pungan
- Departments of Pediatrics & Medicine, Tulane University School of Medicine, New Orleans, United States of America
| | - Anna Ebacher
- Departments of Pediatrics & Medicine, Tulane University School of Medicine, New Orleans, United States of America
| | - Janet E McCombs
- Departments of Pediatrics & Medicine, Tulane University School of Medicine, New Orleans, United States of America
| | - Samuel J Landry
- Department of Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, United States of America
| | - Jay K Kolls
- Departments of Pediatrics & Medicine, Tulane University School of Medicine, New Orleans, United States of America
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Proteomic Profiling and Functional Analysis of B Cell-Derived Exosomes upon Pneumocystis Infection. J Immunol Res 2022; 2022:5187166. [PMID: 35465354 PMCID: PMC9023222 DOI: 10.1155/2022/5187166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/30/2022] [Indexed: 12/27/2022] Open
Abstract
Pneumocystis is a life-threatening fungal pathogen that frequently causes fatal pneumonia (PCP) in immunocompromised individuals. Recently, B cells have been reported to play a crucial role in the pathogenesis of PCP through producing antibodies and activating CD4+ T cell response. Exosomes are nanoscale small extracellular vesicles abundant with protein cargo and can mediate immune response during infectious disease. In this study, using tandem mass tag-based quantitative proteomics coupled with bioinformatic analysis, we attempted to characterize exosomes derived from B lymphocytes in response to PCP. Several proteins were verified by parallel reaction monitoring (PRM) analysis. Also, the effects of B cell exosomes on CD4+ T cell response and phagocytic function of macrophages were clarified. Briefly, 1701 proteins were identified from B cell exosomes, and the majority of them were reported in Vesiclepedia. A total of 51 differentially expressed proteins of B cell exosomes were found in response to PCP. They were mainly associated with immune response and transcription regulation. PRM analysis confirmed the significantly changed levels of histone H1.3, vimentin, and tyrosine-protein phosphatase nonreceptor type 6 (PTPN6). Moreover, a functional study revealed the proinflammatory profile of B cell exosomes on CD4+ T cell response in PCP. Taken together, our results suggest the involvement of exosomes derived from B cells in cell-to-cell communication, providing new information on the function of B cells in response to PCP.
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Bias of the Immune Response to Pneumocystis murina Does Not Alter the Ability of Neonatal Mice to Clear the Infection. J Fungi (Basel) 2021; 7:jof7100827. [PMID: 34682248 PMCID: PMC8537783 DOI: 10.3390/jof7100827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/25/2021] [Accepted: 09/29/2021] [Indexed: 11/17/2022] Open
Abstract
Newborn mice are unable to clear Pneumocystis (PC) infection with the same efficiency as adults due, in part, to their inability to develop a robust immune response to infection until three weeks of age. It is known that infants tend develop a Th2 skewed response to antigen so we sought to determine whether a biased cytokine response altered the clearance of PC infection in neonatal mice. P. murina infection in neonatal mice resulted in increased IL-4 expression by CD4 T cells and myeloid cells, augmented IL-13 secretion within the airways and increased arginase activity in the airways, indicative of Th2-type responses. P. murina-infected IL-4Rα-/- neonates had a shift towards Th1 cytokine production and increased numbers of CD4 and CD8 T cells within the lung as well as elevated levels of P. murina-specific IgG. IFNγ-/- and IL-23 p19-/- mice had altered CD4-T cell-dependent cytokine and cell responses. Though we could alter the T helper cell environment in neonatal knockout mice, there was no loss in the ability of these pups to clear infection. It is possible that the Th2 phenotype normally seen in neonatal mice protects the developing lung from pro-inflammatory immune responses without compromising host defense against P. murina.
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Charpentier E, Ménard S, Marques C, Berry A, Iriart X. Immune Response in Pneumocystis Infections According to the Host Immune System Status. J Fungi (Basel) 2021; 7:jof7080625. [PMID: 34436164 PMCID: PMC8399367 DOI: 10.3390/jof7080625] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 12/12/2022] Open
Abstract
The host immune response is critical in Pneumocystis pneumonia (PCP). Immunocompetent hosts can eliminate the fungus without symptoms, while immunodeficient hosts develop PCP with an unsuitable excessive inflammatory response leading to lung damage. From studies based on rodent models or clinical studies, this review aimed to better understand the pathophysiology of Pneumocystis infection by analysing the role of immune cells, mostly lymphocytes, according to the immune status of the infected host. Hence, this review first describes the immune physiological response in infected immunocompetent hosts that are able to eliminate the fungus. The objective of the second part is to identify the immune elements required for the control of the fungus, focusing on specific immune deficiencies. Finally, the third part concentrates on the effect of the different immune elements in immunocompromised subjects during PCP, to better understand which cells are detrimental, and which, on the contrary, are beneficial once the disease has started. This work highlights that the immune response associated with a favourable outcome of the infection may differ according to the immune status of the host. In the case of immunocompetency, a close communication between B cells and TCD4 within tertiary lymphocyte structures appears critical to activate M2 macrophages without much inflammation. Conversely, in the case of immunodeficiency, a pro-inflammatory response including Th1 CD4, cytotoxic CD8, NK cells, and IFNγ release seems beneficial for M1 macrophage activation, despite the impact of inflammation on lung tissue.
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Affiliation(s)
- Eléna Charpentier
- Department of Parasitology-Mycology, Toulouse University Hospital, 31059 Toulouse, France;
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
- Correspondence: (E.C.); (X.I.)
| | - Sandie Ménard
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
| | - Catherine Marques
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
| | - Antoine Berry
- Department of Parasitology-Mycology, Toulouse University Hospital, 31059 Toulouse, France;
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
| | - Xavier Iriart
- Department of Parasitology-Mycology, Toulouse University Hospital, 31059 Toulouse, France;
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
- Correspondence: (E.C.); (X.I.)
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Survey of the Transcription Factor Responses of Mouse Lung Alveolar Macrophages to Pneumocystis murina. Pathogens 2021; 10:pathogens10050569. [PMID: 34066663 PMCID: PMC8151842 DOI: 10.3390/pathogens10050569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/03/2021] [Accepted: 05/07/2021] [Indexed: 11/16/2022] Open
Abstract
Pneumocystis jirovecii is a fungal pathogen that can cause life-threatening infections in individuals who are immunocompromised. Acquired via inhalation, upon entering the respiratory tract, the fungi first encounter innate immune cells such as alveolar macrophages (AMs). Relatively little is known about the AM cellular responses to the organism, and particularly transcription factor (TF) profiles leading to early host responses during infection. Utilizing the Mouse Transcription Factors RT2 Profiler™ PCR Array, we report an initial TF survey of these macrophage and Pneumocystis interactions. Expression levels of a panel of mouse TFs were compared between unstimulated and Pneumocystis murina-stimulated AMs. Interestingly, a number of TFs previously implicated in pathogen–host cell interactions were highly up- or downregulated, including hif1a and Pparg. qPCR experiments were further conducted to verify the results of these surveyed transcripts. Furthermore, with immunoblotting, we show that HIF-1A and PPAR-γ are indeed significantly upregulated and downregulated, respectively. Lastly, and importantly, we report that in the mouse model of Pneumocystis pneumonia (PCP), which mimics human Pneumocystis jirovecii pneumonia (PJP), qPCR analysis of Pneumocystis murina lungs also mimic the initial TF profile analysis, suggesting an importance for these TFs in immunocompromised hosts with Pneumocystis pneumonia. These data demonstrate the use of TF profiling in host AMs and Pneumocystis organism interactions that may lead to a better understanding of the specific inflammatory responses of the host to Pneumocystis pneumonia and may inform novel strategies for potential therapeutics.
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Kim YH, Kim JY, Kim DH, Ko Y, Choi JY, Shin S, Jung JH, Park SK, Kim SH, Kwon H, Han DJ. Pneumocystis pneumonia occurrence and prophylaxis duration in kidney transplant recipients according to perioperative treatment with rituximab. BMC Nephrol 2020; 21:93. [PMID: 32160881 PMCID: PMC7066802 DOI: 10.1186/s12882-020-01750-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/28/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Pneumocystis pneumonia (PCP) is a life-threatening fungal infection that can occur in kidney transplantation (KT) recipients. A growing number of KT recipients are receiving perioperative treatment with rituximab, which is associated with prolonged B-cell depletion and possible risk of PCP occurrence; however, the optimal prophylaxis duration according to rituximab treatment is yet unknown. We compared the occurrence of PCP and the duration of prophylaxis in KT recipients according to rituximab treatment. METHODS We retrospectively analyzed 2110 patients who underwent KT between January 2009 and December 2016, who were divided into non-Rituximab group (n = 1588, 75.3%) and rituximab group (n = 522, 24.7%). RESULTS In the rituximab group, the estimated number needed to treat (NNT) for prophylaxis prolongation from 6 to 12 months was 29.0 with a relative risk reduction of 90.0%. In the non-rituximab group, the estimated NNT value was 133.3 and the relative risk reduction was 66.4%. Rituximab treatment (hazard ratio (HR) = 3.09; P < 0.01) and acute rejection (HR = 2.19; P = 0.03) were significant risk factors for PCP in multivariate analysis. CONCLUSIONS Our results suggest that maintaining PCP prophylaxis for 12 months may be beneficial in KT recipients treated with rituximab for desensitization or acute rejection treatment.
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Affiliation(s)
- Young Hoon Kim
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Jee Yeon Kim
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Dong Hyun Kim
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Youngmin Ko
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Ji Yoon Choi
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Sung Shin
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Joo Hee Jung
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
| | - Su-Kil Park
- Division of Nephrology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Sung-Han Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Hyunwook Kwon
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea.
| | - Duck Jong Han
- Division of Kidney and Pancreas Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, South Korea
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IL-17 Inversely Correlated with IL-10 via the STAT3 Gene in Pneumocystis-Infected Mice. Mediators Inflamm 2019; 2019:6750861. [PMID: 31582901 PMCID: PMC6754930 DOI: 10.1155/2019/6750861] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 07/10/2019] [Accepted: 07/26/2019] [Indexed: 01/05/2023] Open
Abstract
Background Pneumocystis pneumonia (PCP) remains a common opportunistic infection in immunosuppressed individuals. Current studies showed that multiple immune cells and cytokines took part in the host defense against Pneumocystis (PC). However, the roles of IL-17 and IL-10 in the development of PCP have not been elucidated. Methods IL-10 and IL-17 levels in serum from PCP mice were detected via ELISA. The percentages of B10 cells, IL-10+ macrophages, and IL-10+ T cells in the lung from IL-17–/– PCP mice and Th17 cells and IL-17+γδT cells in IL-10–/– PCP mice were examined via flow cytometry. Also, antibody neutralization examination was also performed to elucidate the relationship of IL-17 and IL-10 in the PCP model. Results We noted the increase of IL-17 and IL-10 levels in serum from mice infected with Pneumocystis. Furthermore, deficiency of IL-17 or IL-10 could lead to the delayed clearance of Pneumocystis and more severed lung damage. Our data also demonstrated that IL-17 deficiency enhanced the serum IL-10 level and the percentages of B10 cells, IL-10+ macrophages, and IL-10+ T cells in the lung from PCP mice. Interestingly, we also noted an increase of the IL-17 level in serum and Th17 cell and IL-17+γδT cell percentages in the lung from IL-10–/– PCP mice. Using antibody neutralization experiments, we found that the STAT3 gene might play a critical role in the interplay of IL-17 and IL-10 in PCP. Conclusion Taken together, our results demonstrated that IL-17 and IL-10 could play the protective roles in the progression of PCP and the inverse correlation of them might be mediated by STAT3.
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Evans HM, Garvy BA. The trophic life cycle stage of Pneumocystis species induces protective adaptive responses without inflammation-mediated progression to pneumonia. Med Mycol 2019; 56:994-1005. [PMID: 29267980 DOI: 10.1093/mmy/myx145] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 11/22/2017] [Indexed: 12/28/2022] Open
Abstract
Pneumocystis species are fungal pathogens that cause pneumonia in immunocompromised hosts. Lung damage during Pneumocystis pneumonia is predominately due to the inflammatory immune response. Pneumocystis species have a biphasic life cycle. Optimal innate immune responses to Pneumocystis species are dependent on stimulation with the cyst life cycle stage. Conversely, the trophic life cycle stage broadly suppresses proinflammatory responses to multiple pathogen-associated molecular patterns (PAMPs), including β-1,3-glucan. Little is known about the contribution of these life cycle stages to the development of protective adaptive responses to Pneumocystis infection. Here we report that CD4+ T cells primed in the presence of trophic forms are sufficient to mediate clearance of trophic forms and cysts. In addition, primary infection with trophic forms is sufficient to prime B-cell memory responses capable of clearing a secondary infection with Pneumocystis following CD4+ T cell depletion. While trophic forms are sufficient for initiation of adaptive immune responses in immunocompetent mice, infection of immunocompromised recombination-activating gene 2 knockout (RAG2-/-) mice with trophic forms in the absence of cysts does not lead to the severe weight loss and infiltration of innate immune cells associated with the development of Pneumocystis pneumonia.
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Affiliation(s)
- Heather M Evans
- Department of Microbiology, Immunology, and Molecular Genetics
| | - Beth A Garvy
- Department of Microbiology, Immunology, and Molecular Genetics.,Division of Infectious Diseases, College of Medicine, University of Kentucky, Lexington, Kentucky
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Rong HM, Li T, Zhang C, Wang D, Hu Y, Zhai K, Shi HZ, Tong ZH. IL-10-producing B cells regulate Th1/Th17-cell immune responses in Pneumocystis pneumonia. Am J Physiol Lung Cell Mol Physiol 2018; 316:L291-L301. [PMID: 30284926 DOI: 10.1152/ajplung.00210.2018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Pneumocystis pneumonia (PCP) is a common opportunistic infectious disease that is prevalent in immunosuppressed hosts. Accumulating evidence shows that B cells play an important role in infectious diseases. In the present study, the immune regulatory role of mature B cells in host defense to Pneumocystis was evaluated. Pneumocystis infection resulted in a decrease in B cells in patients and mice, and the Pneumocystis burden in B cell-deficient mice also progressively increased from weeks 1 to 7 after infection. The clearance of Pneumocystis was delayed in B cell-activating factor receptor (BAFF-R)-deficient mice (BAFF-R-/- mice), which had few B cells and Pneumocystis-specific IgG and IgM antibodies, compared with clearance in wild-type (WT) mice. There were fewer effector CD4+ T cells and higher percentages of T helper (Th)1/Th17 cells in BAFF-R-/- mice than in WT mice. Adoptive transfer of naive B cells, mRNA sequencing, and IL-1β neutralization experiments indicated that IL-1β is a likely determinant of the IL-10-producing B cell-mediated suppression of Th1/Th17-cell immune responses in BAFF-R-/- PCP mice. Our data indicated that B cells play a vital role in the regulation of Th cells in response to Pneumocystis infection.
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Affiliation(s)
- Heng-Mo Rong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Ting Li
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Chao Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Dong Wang
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Yang Hu
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Kan Zhai
- Department of Medical Research Center, Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Huan-Zhong Shi
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
| | - Zhao-Hui Tong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University , Beijing , China
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Pneumocystis jirovecii pneumonia in HIV-uninfected, rituximab treated non-Hodgkin lymphoma patients. Sci Rep 2018; 8:8321. [PMID: 29844519 PMCID: PMC5974272 DOI: 10.1038/s41598-018-26743-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 05/16/2018] [Indexed: 01/03/2023] Open
Abstract
Rituximab is associated with a higher incidence of Pneumocystis jirovecii pneumonia infection. Pneumocystis prophylaxis is advised in many immunocompromised populations treated with rituximab. However, the beneficial effect of pneumocystis prophylaxis in HIV-uninfected, rituximab-treated non-Hodgkin lymphoma (NHL) patients has not been assessed. Thus, we conducted this retrospective study to explore pneumocystis infection in HIV-uninfected NHL patients who received at least three courses of chemotherapy without haematopoietic stem cell transplantation using the Taiwan National Health Insurance Research Database. Patients who had rituximab-based chemotherapy were included in the experimental (rituximab) group, while the rest of the patients who did not receive any rituximab-based chemotherapy throughout the study period formed the control group. The prevalence rate of pneumocystis infection in the rituximab group (N = 7,554) was significantly higher than that in the control group (N = 4,604) (2.95% vs. 1.32%). The onset of pneumocystis infection occurred between 6 and 16 weeks after chemotherapy. Patients who had pneumocystis prophylaxis, whether or not they had a pneumocystis infection later in their treatment course, had significantly better first-year survival rates (73% vs. 38%). Regular pneumocystis prophylaxis should be considered in this group of patients.
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Li T, Rong HM, Zhang C, Zhai K, Tong ZH. IL-9 Deficiency Promotes Pulmonary Th17 Response in Murine Model of Pneumocystis Infection. Front Immunol 2018; 9:1118. [PMID: 29887863 PMCID: PMC5980981 DOI: 10.3389/fimmu.2018.01118] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/03/2018] [Indexed: 12/21/2022] Open
Abstract
Introduction Pneumocystis pneumonia (PCP) remains a severe complication with high mortality in immunocompromised patients. It has been well accepted that CD4+ T cells play a major role in controlling Pneumocystis infection. Th9 cells were the main source of IL-9 with multifaced roles depending on specific diseases. It is unclear whether IL-9/Th9 contributes to the immune response against PCP. The current study aims to explore the role of IL-9 and the effect of IL-9 on Th17 cells in murine model of PCP. Materials and methods Mice were intratracheally injected with 1 × 106Pneumocystis organisms to establish the murine model of Pneumocystis infection. Pneumocystis burden was detected by TaqMan real-time PCR. Using IL-9-deficient (IL-9−/−) mice, flow cytometry, real-time PCR and enzyme-linked immunosorbent assay (ELISA) were conducted to investigate the immune function related to Th17 response in defense against Pneumocystis infection. Results Reduced Pneumocystis burden was observed in lungs in IL-9−/− mice compared with WT mice at 3-week postinfection. IL-9−/−mice exhibited stronger Th17 immune responses than WT PCP mice through flow cytometer and real-time PCR. ELISA revealed higher levels of IL-17 and IL-23 in bronchoalveolar lavage fluid from IL-9−/− mice than WT mice. And IL-9 deficiency promoted Th17 differentiation from CD4+ naive T cells. IL-17A neutralization increased Pneumocystis burden in IL-9−/− mice. Conclusion Although similar basic clearance of Pneumocystis organisms was achieved in both WT and IL-9−/− PCP mice, IL-9 deficiency could lower Pneumocystis organism burden and promote pulmonary Th17 cells response in the early stage of infection.
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Affiliation(s)
- Ting Li
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Heng-Mo Rong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Chao Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Kan Zhai
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Zhao-Hui Tong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine and Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
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Pneumocystis Pneumonia during Rituximab Treatment in Children with Autoimmune Nerve System Diseases. J Neuroimmune Pharmacol 2018; 13:277-278. [DOI: 10.1007/s11481-018-9791-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/10/2018] [Indexed: 10/16/2022]
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Hakansson AP, Orihuela CJ, Bogaert D. Bacterial-Host Interactions: Physiology and Pathophysiology of Respiratory Infection. Physiol Rev 2018; 98:781-811. [PMID: 29488821 PMCID: PMC5966719 DOI: 10.1152/physrev.00040.2016] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 09/08/2017] [Accepted: 09/11/2017] [Indexed: 02/06/2023] Open
Abstract
It has long been thought that respiratory infections are the direct result of acquisition of pathogenic viruses or bacteria, followed by their overgrowth, dissemination, and in some instances tissue invasion. In the last decades, it has become apparent that in contrast to this classical view, the majority of microorganisms associated with respiratory infections and inflammation are actually common members of the respiratory ecosystem and only in rare circumstances do they cause disease. This suggests that a complex interplay between host, environment, and properties of colonizing microorganisms together determines disease development and its severity. To understand the pathophysiological processes that underlie respiratory infectious diseases, it is therefore necessary to understand the host-bacterial interactions occurring at mucosal surfaces, along with the microbes inhabiting them, during symbiosis. Current knowledge regarding host-bacterial interactions during asymptomatic colonization will be discussed, including a plausible role for the human microbiome in maintaining a healthy state. With this as a starting point, we will discuss possible disruptive factors contributing to dysbiosis, which is likely to be a key trigger for pathobionts in the development and pathophysiology of respiratory diseases. Finally, from this renewed perspective, we will reflect on current and potential new approaches for treatment in the future.
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Affiliation(s)
- A P Hakansson
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University , Lund , Sweden ; Department of Microbiology, University of Alabama at Birmingham , Birmingham, Alabama ; and Center for Inflammation Research, Queens Medical Research Institute, University of Edinburgh , Edinburgh , United Kingdom
| | - C J Orihuela
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University , Lund , Sweden ; Department of Microbiology, University of Alabama at Birmingham , Birmingham, Alabama ; and Center for Inflammation Research, Queens Medical Research Institute, University of Edinburgh , Edinburgh , United Kingdom
| | - D Bogaert
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University , Lund , Sweden ; Department of Microbiology, University of Alabama at Birmingham , Birmingham, Alabama ; and Center for Inflammation Research, Queens Medical Research Institute, University of Edinburgh , Edinburgh , United Kingdom
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Khan BA, Khan S, White B, Eranki A. Severe pneumocystis jiroveci pneumonia in a patient on temozolomide therapy: A case report and review of literature. Respir Med Case Rep 2017; 22:179-182. [PMID: 28861334 PMCID: PMC5568882 DOI: 10.1016/j.rmcr.2017.08.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/31/2017] [Accepted: 08/11/2017] [Indexed: 11/17/2022] Open
Abstract
A 66 year old man was diagnosed with CNS diffuse large B-cell lymphoma, and underwent treatment with Temozolomide, Dexamethasone, Rituximab, and radiation therapy, and prolonged steroid taper with Dexamethasone. Approximately one month after this, he presented with severe acute hypoxemic respiratory failure, and was admitted to the Medical Intensive Care Unit. Imaging showed diffuse ground glass opacities. Patient underwent diagnostic bronchoalveolar lavage which was positive for Pneumocystis jiroveci. He did not respond well to appropriate therapy and was transitioned to comfort care per his family's wishes, and expired. Pneumocystis jiroveci should always be included in the differential diagnosis of pneumonia in patients treated with Temozolomide, especially when this agent is used in combination with long term, high dose corticosteroids and radiation therapy.
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Hu Y, Wang D, Zhai K, Tong Z. Transcriptomic Analysis Reveals Significant B Lymphocyte Suppression in Corticosteroid-Treated Hosts with Pneumocystis Pneumonia. Am J Respir Cell Mol Biol 2017; 56:322-331. [PMID: 27788015 DOI: 10.1165/rcmb.2015-0356oc] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Pneumocystis pneumonia (PCP) is an opportunistic, infectious disease that is prevalent in immunosuppressed hosts. Corticosteroid treatment is the most significant risk factor for patients with PCP who are human immunodeficiency virus negative, although little is known about how corticosteroids alter the host defense against Pneumocystis infection. In the present study, we used transcriptome analysis to examine the immune response in the lungs of corticosteroid-treated PCP mice. The results showed down-regulation in the genes related to both native immunity, such as antigen processing and presentation, inflammatory response, and phagocytosis, as well as B and T lymphocyte immunity. The repression of gene expression, corresponding to B cell immunity, including B cell signaling, homeostasis, and Ig production, was prominent. The finding was confirmed by quantitative PCR of mouse lungs and the peripheral blood of patients with PCP. Flow cytometry also revealed a significant depletion of B cells in corticosteroid-treated PCP mice. Our study has highlighted that corticosteroid treatment suppresses the B cell immunity in the PCP host, which is likely one of the main reasons that corticosteroid treatment may stimulate PCP development.
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Affiliation(s)
- Yang Hu
- 1 Department of Respiratory Medicine and Critical Care Medicine, and
| | - Dong Wang
- 1 Department of Respiratory Medicine and Critical Care Medicine, and
| | - Kan Zhai
- 2 Department of Medical Research Center, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Zhaohui Tong
- 1 Department of Respiratory Medicine and Critical Care Medicine, and
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Barreto JN, Ice LL, Thompson CA, Tosh PK, Osmon DR, Dierkhising RA, Plevak MF, Limper AH. Low incidence of pneumocystis pneumonia utilizing PCR-based diagnosis in patients with B-cell lymphoma receiving rituximab-containing combination chemotherapy. Am J Hematol 2016; 91:1113-1117. [PMID: 27472910 DOI: 10.1002/ajh.24499] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/25/2022]
Abstract
Recent literature has demonstrated concern over the risk of Pneumocystis jirovecii pneumonia (PJP) when administering rituximab with combination chemotherapy such as in R-CHOP; however, the exact risk and potential need for prophylaxis is unknown. We sought to determine the incidence of PJP infection following R-CHOP administration in patients with B-cell lymphoma. Consecutive patients diagnosed with B-cell lymphoma receiving R-CHOP were evaluated from chemotherapy initiation until 180 days after the last administration. The primary outcome was cumulative incidence of PJP infection. Secondary endpoints included the association of rituximab, prednisone and subsequent chemotherapy with PJP infection risk. A total of 689 patients (53% male, median age 66 years) were included. Seventy-three percent of patients completed at least 6 cycles of R-CHOP treatment. Median rituximab and prednisone cumulative doses were 3950 mg and 5325 mg, respectively. Median daily prednisone dose through end of treatment was 45 mg (range 7.6 mg to 119 mg). The cumulative incidence of PJP was 1.51% (95% CI 0.57-2.43, at maximum follow-up of 330 days), below 3.5%, the conventional threshold for prophylaxis. Univariate analysis did not detect a statistically significant association between PJP and rituximab, steroids, or receipt of additional chemotherapy in this patient population. Our results demonstrate a low occurrence of Pneumocystis pneumonia during R-CHOP treatment of B-cell lymphoma and argue against universal anti-Pneumocystis prophylaxis in this setting. Further investigations should focus on targeted anti-Pneumocystis prophylaxis for patients presenting with high-risk baseline characteristics or when receiving rituximab-inclusive intensive combination chemotherapy regimens as treatment for other aggressive lymphoma subtypes. Am. J. Hematol. 91:1113-1117, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Jason N. Barreto
- Department of Pharmacy Services; Mayo Clinic; Rochester Minnesota
| | - Lauren L. Ice
- Department of Pharmacy; Spectrum Health; Grand Rapids Michigan
| | - Carrie A. Thompson
- Division of Hematology; Department of Internal Medicine, Mayo Clinic; Rochester Minnesota
| | - Pritish K. Tosh
- Division of Infectious Diseases; Department of Internal Medicine, Mayo Clinic; Rochester Minnesota
| | - Douglas R. Osmon
- Division of Infectious Diseases; Department of Internal Medicine, Mayo Clinic; Rochester Minnesota
| | - Ross A. Dierkhising
- Division of Biomedical Statistics and Informatics; Mayo Clinic; Rochester Minnesota
| | - Matthew F. Plevak
- Division of Biomedical Statistics and Informatics; Mayo Clinic; Rochester Minnesota
| | - Andrew H. Limper
- Division of Pulmonary and Critical Care Medicine; Department of Internal Medicine, Mayo Clinic; Rochester Minnesota
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Intermittent Courses of Corticosteroids Also Present a Risk for Pneumocystis Pneumonia in Non-HIV Patients. Can Respir J 2016; 2016:2464791. [PMID: 27721666 PMCID: PMC5046011 DOI: 10.1155/2016/2464791] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 08/18/2016] [Indexed: 01/03/2023] Open
Abstract
Introduction. Pneumocystis pneumonia (PCP) is rising in the non-HIV population and associates with higher morbidity and mortality. The aggressive immunosuppressive regimens, as well as the lack of stablished guidelines for chemoprophylaxis, are likely contributors to this increased incidence. Herein, we have explored the underlying conditions, immunosuppressive therapies, and clinical outcomes of PCP in HIV-negative patients. Methods. Retrospective analysis of PCP in HIV-negative patients at Mayo Clinic from 2006–2010. The underlying condition, immunosuppressive therapies, coinfection, and clinical course were determined. PCP diagnosis required symptoms of pneumonia and identification of the organisms by visualization or by a real-time polymerase chain reaction. Results. A total of 128 cases of PCP were identified during the study period. Hematological malignancies were the predisposing condition for 50% of the patients. While 87% had received corticosteroids or other immunosuppressive therapies for >4 weeks prior to the diagnosis, only 7 were receiving PCP prophylaxis. Up to 43% of patients were not on daily steroids. Sixty-seven patients needed Intensive Care Unit (ICU) and 53 received mechanical ventilation. The mortality for those patients requiring ICU was 40%. Conclusions. PCP diagnosis in the HIV-negative population requires a high level of suspicion even if patients are not receiving daily corticosteroids. Mortality remains high despite adequate treatment.
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The life cycle stages of Pneumocystis murina have opposing effects on the immune response to this opportunistic, fungal pathogen. Infect Immun 2016; 84:3195-3205. [PMID: 27572330 PMCID: PMC5067752 DOI: 10.1128/iai.00519-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The cyst cell wall β-glucans of Pneumocystis have been shown to stimulate immune responses in lung epithelial cells, dendritic cells, and alveolar macrophages. Little is known about how the trophic life forms, which do not have a fungal cell wall, interact with these innate immune cells. Here, we report differences in the responses of both neonatal and adult mice to the trophic and cystic life cycle stages of Pneumocystis murina The adult and neonatal immune responses to infection with Pneumocystis murina trophic forms were less robust than the response to infection with a physiologically normal mixture of cysts and trophic forms. Cysts promoted the recruitment of nonresident innate immune cells and T and B cells into the lungs. Cysts, but not trophic forms, stimulated increased IFN-γ cytokine concentrations in the alveolar spaces, and an increase in IFN-γ-producing CD4+ T cells. In vitro, bone marrow-derived dendritic cells (BMDCs) stimulated with cysts produced the proinflammatory cytokines IL-1β and IL-6. In contrast, trophic forms suppressed β-glucan-, LTA-, and LPS-induced IL-1β, IL-6, and TNFα production by BMDCs and antigen presentation to CD4+ T cells. The negative effects of trophic forms were not due to ligation of mannose receptor. Our results indicate that optimal innate and adaptive immune responses to Pneumocystis species are dependent on stimulation with the cyst life cycle stage. Conversely, trophic forms suppress β-glucan-induced proinflammatory responses in vitro, suggesting that the trophic forms dampen cyst-induced inflammation in vivo.
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Goto N, Futamura K, Okada M, Yamamoto T, Tsujita M, Hiramitsu T, Narumi S, Watarai Y. Management of Pneumocystis jirovecii Pneumonia in Kidney Transplantation to Prevent Further Outbreak. CLINICAL MEDICINE INSIGHTS-CIRCULATORY RESPIRATORY AND PULMONARY MEDICINE 2015; 9:81-90. [PMID: 26609250 PMCID: PMC4648609 DOI: 10.4137/ccrpm.s23317] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 08/11/2015] [Accepted: 08/12/2015] [Indexed: 12/19/2022]
Abstract
The outbreak of Pneumocystis jirovecii pneumonia (PJP) among kidney transplant recipients is emerging worldwide. It is important to control nosocomial PJP infection. A delay in diagnosis and treatment increases the number of reservoir patients and the number of cases of respiratory failure and death. Owing to the large number of kidney transplant recipients compared to other types of organ transplantation, there are greater opportunities for them to share the same time and space. Although the use of trimethoprim-sulfamethoxazole (TMP-SMX) as first choice in PJP prophylaxis is valuable for PJP that develops from infections by trophic forms, it cannot prevent or clear colonization, in which cysts are dominant. Colonization of P. jirovecii is cleared by macrophages. While recent immunosuppressive therapies have decreased the rate of rejection, over-suppressed macrophages caused by the higher levels of immunosuppression may decrease the eradication rate of colonization. Once a PJP cluster enters these populations, which are gathered in one place and uniformly undergoing immunosuppressive therapy for kidney transplantation, an outbreak can occur easily. Quick actions for PJP patients, other recipients, and medical staff of transplant centers are required. In future, lifelong prophylaxis may be required even in kidney transplant recipients.
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Affiliation(s)
- Norihiko Goto
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Kenta Futamura
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Manabu Okada
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Takayuki Yamamoto
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Makoto Tsujita
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Takahisa Hiramitsu
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Shunji Narumi
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Yoshihiko Watarai
- Department of Transplant Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
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Opata MM, Hollifield ML, Lund FE, Randall TD, Dunn R, Garvy BA, Feola DJ. B Lymphocytes Are Required during the Early Priming of CD4+ T Cells for Clearance of Pneumocystis Infection in Mice. THE JOURNAL OF IMMUNOLOGY 2015; 195:611-20. [PMID: 26041535 DOI: 10.4049/jimmunol.1500112] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 05/12/2015] [Indexed: 11/19/2022]
Abstract
B cells play a critical role in the clearance of Pneumocystis. In addition to production of Pneumocystis-specific Abs, B cells are required during the priming phase for CD4(+) T cells to expand normally and generate memory. Clearance of Pneumocystis was found to be dependent on Ag specific B cells and on the ability of B cells to secrete Pneumocystis-specific Ab, as mice with B cells defective in these functions or with a restricted BCR were unable to control Pneumocystis infection. Because Pneumocystis-specific antiserum was only able to partially protect B cell-deficient mice from infection, we hypothesized that optimal T cell priming requires fully functional B cells. Using adoptive transfer and B cell depletion strategies, we determined that optimal priming of CD4(+) T cells requires B cells during the first 2-3 d of infection and that this was independent of the production of Ab. T cells that were removed from Pneumocystis-infected mice during the priming phase were fully functional and able to clear Pneumocystis infection upon adoptive transfer into Rag1(-/-) hosts, but this effect was ablated in mice that lacked fully functional B cells. Our results indicate that T cell priming requires a complete environment of Ag presentation and activation signals to become fully functional in this model of Pneumocystis infection.
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Affiliation(s)
- Michael M Opata
- Division of Infectious Diseases, Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
| | - Melissa L Hollifield
- Division of Infectious Diseases, Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
| | - Frances E Lund
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Troy D Randall
- Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Robert Dunn
- Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121; and
| | - Beth A Garvy
- Division of Infectious Diseases, Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536;
| | - David J Feola
- Department of Pharmacy Practice and Science, University of Kentucky College of Pharmacy, Lexington, KY 40536
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Anti-CD20 antibody therapy and susceptibility to Pneumocystis pneumonia. Infect Immun 2015; 83:2043-52. [PMID: 25733518 DOI: 10.1128/iai.03099-14] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 02/25/2015] [Indexed: 11/20/2022] Open
Abstract
Anti-CD20 antibody therapy has been a useful medication for managing non-Hodgkin's lymphoma as well as autoimmune diseases characterized by autoantibody generation. CD20 is expressed during most developmental stages of B lymphocytes; thus, CD20 depletion leads to B-lymphocyte deficiency. As the drug has become more widely used, there has been an increase in the number of case reports of patients developing Pneumocystis pneumonia. The role of anti-CD20 in Pneumocystis jirovecii infection is under debate due to the fact that most patients receiving it are on a regimen of multiple immunosuppressive medications. To address the specific role of CD20 depletion in host immunity against Pneumocystis, we examined a murine anti-CD20 depleting antibody. We demonstrated that anti-CD20 alone is permissive for Pneumocystis infection and that anti-CD20 impairs components of type II immunity, such as production of interleukin-4 (IL-4), IL-5, and IL-13 by whole-lung cells, in response to Pneumocystis murina. We also demonstrated that CD4(+) T cells from mice treated with anti-CD20 during Pneumocystis infection are incapable of mounting a protective immune response when transferred into Rag1(-/-) mice. Thus, CD20(+) cells are critical for generating protective CD4(+) T-cell immune responses against this organism.
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Hoyt TR, Dobrinen E, Kochetkova I, Meissner N. B cells modulate systemic responses to Pneumocystis murina lung infection and protect on-demand hematopoiesis via T cell-independent innate mechanisms when type I interferon signaling is absent. Infect Immun 2015; 83:743-58. [PMID: 25452554 PMCID: PMC4294237 DOI: 10.1128/iai.02639-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 11/26/2014] [Indexed: 12/20/2022] Open
Abstract
HIV infection results in a complex immunodeficiency due to loss of CD4(+) T cells, impaired type I interferon (IFN) responses, and B cell dysfunctions causing susceptibility to opportunistic infections such as Pneumocystis murina pneumonia and unexplained comorbidities, including bone marrow dysfunctions. Type I IFNs and B cells critically contribute to immunity to Pneumocystis lung infection. We recently also identified B cells as supporters of on-demand hematopoiesis following Pneumocystis infection that would otherwise be hampered due to systemic immune effects initiated in the context of a defective type I IFN system. While studying the role of type I IFNs in immunity to Pneumocystis infection, we discovered that mice lacking both lymphocytes and type I IFN receptor (IFrag(-/-)) developed progressive bone marrow failure following infection, while lymphocyte-competent type I IFN receptor-deficient mice (IFNAR(-/-)) showed transient bone marrow depression and extramedullary hematopoiesis. Lymphocyte reconstitution of lymphocyte-deficient IFrag(-/-) mice pointed to B cells as a key player in bone marrow protection. Here we define how B cells protect on-demand hematopoiesis following Pneumocystis lung infection in our model. We demonstrate that adoptive transfer of B cells into IFrag(-/-) mice protects early hematopoietic progenitor activity during systemic responses to Pneumocystis infection, thus promoting replenishment of depleted bone marrow cells. This activity is independent of CD4(+) T cell help and B cell receptor specificity and does not require B cell migration to bone marrow. Furthermore, we show that B cells protect on-demand hematopoiesis in part by induction of interleukin-10 (IL-10)- and IL-27-mediated mechanisms. Thus, our data demonstrate an important immune modulatory role of B cells during Pneumocystis lung infection that complement the modulatory role of type I IFNs to prevent systemic complications.
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Affiliation(s)
- Teri R Hoyt
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA
| | - Erin Dobrinen
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA
| | - Irina Kochetkova
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA
| | - Nicole Meissner
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA
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Abstract
Today’s laboratory mouse, Mus musculus, has its origins as the ‘house mouse’ of North America and Europe. Beginning with mice bred by mouse fanciers, laboratory stocks (outbred) derived from M. musculus musculus from eastern Europe and M. m. domesticus from western Europe were developed into inbred strains. Since the mid-1980s, additional strains have been developed from Asian mice (M. m. castaneus from Thailand and M. m. molossinus from Japan) and from M. spretus which originated from the western Mediterranean region.
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Fatal Late-Onset Pneumocystis Pneumonia After Rituximab: Administration for Posttransplantation Recurrence of Focal Segmental Glomerulosclerosis—Case Report. Transplant Proc 2014; 46:2908-11. [DOI: 10.1016/j.transproceed.2014.09.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Chalasani G, Rothstein D. Non-Antibody Mediated Roles of B Cells in Allograft Survival. CURRENT TRANSPLANTATION REPORTS 2014. [DOI: 10.1007/s40472-014-0020-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Mollo SB, Zajac AJ, Harrington LE. Temporal requirements for B cells in the establishment of CD4 T cell memory. THE JOURNAL OF IMMUNOLOGY 2013; 191:6052-9. [PMID: 24218454 DOI: 10.4049/jimmunol.1302033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
CD4 T cell memory generation is shaped by a number of factors, including the strength and duration of TCR signaling, as well as the priming environment, all of which can be modified by B cells. Studies using B cell-deficient mice indicate B cells play a critical role in generating effector and memory CD4 T cells; however, when and how B cells are acting to promote these responses has not yet been ascertained. In this study, we use anti-CD20 Ab depletion of B cells at different times following Listeria monocytogenes infection to show that B cells are necessary for the induction of optimal CD4 T cell memory, but not for the transition and maintenance of this population. Importantly, the prerequisite of B cells early postinfection is partially dependent on their expression of MHC class II. B cells are not only required during the priming phase, but also necessary for the initiation of robust secondary responses by memory CD4 T cells. Interestingly, the requirement during the recall response is independent of B cell Ag presentation. Overall, these studies demonstrate the temporally and functionally distinct roles for B cells in regulating CD4 T cell responses.
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Affiliation(s)
- Sarah B Mollo
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
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Martin-Garrido I, Carmona EM, Specks U, Limper AH. Pneumocystis pneumonia in patients treated with rituximab. Chest 2013; 144:258-265. [PMID: 23258406 DOI: 10.1378/chest.12-0477] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Pneumocystis pneumonia (PcP) is an opportunistic fungal infection. Although T-cell immunity is classically related to Pneumocystis defense, recent data support roles for B lymphocytes in the development of PcP in animals, and we have observed several cases of PcP in patients receiving rituximab. These observations prompted a systematic review of our experience to define the spectrum of clinical presentations in which PcP has occurred in the setting of rituximab therapy. METHODS Using a computer-based search, we reviewed the records of patients who received rituximab and developed PcP at Mayo Clinic Rochester over the years 1998 to 2011 to establish the underlying conditions, clinical course, possible risk factors, and potential association between this drug and the development of PcP. RESULTS Over this period, 30 patients developed PcP during treatment with rituximab. The underlying diseases included hematologic malignancies in 90% of cases. Glucocorticoids were used in 73% of these patients, under different chemotherapeutic regimens. Three patients (10%) developed PcP in the setting of rituximab without concomitant chemotherapy or significant glucocorticoid exposure. Of these 30 patients, 88% developed acute hypoxemic respiratory failure and 53% required ICU admission. The clinical course was fatal in 30%. CONCLUSION PcP can occur in association with rituximab, with the majority of cases having also received cytotoxic chemotherapy or significant doses of glucocorticoids. The clinical course of cases of PcP in patients treated with rituximab can be quite fulminant, with significant mortality. Primary prophylaxis should be considered in patients at risk, and secondary prophylaxis provided unless immune reconstitution is well assured.
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Affiliation(s)
- Isabel Martin-Garrido
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic College of Medicine, Rochester, MN; Servicio de Medicina Interna, Hospital Universitario Virgen del Rocío, Seville, Spain
| | - Eva M Carmona
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic College of Medicine, Rochester, MN
| | - Ulrich Specks
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic College of Medicine, Rochester, MN
| | - Andrew H Limper
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic College of Medicine, Rochester, MN.
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Perez-Nazario N, Rangel-Moreno J, O'Reilly MA, Pasparakis M, Gigliotti F, Wright TW. Selective ablation of lung epithelial IKK2 impairs pulmonary Th17 responses and delays the clearance of Pneumocystis. THE JOURNAL OF IMMUNOLOGY 2013; 191:4720-30. [PMID: 24078701 DOI: 10.4049/jimmunol.1301679] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Pneumocystis is an atypical fungal pathogen that causes severe, often fatal pneumonia in immunocompromised patients. Healthy humans and animals also encounter this pathogen, but they generate a protective CD4(+) T cell-dependent immune response that clears the pathogen with little evidence of disease. Pneumocystis organisms attach tightly to respiratory epithelial cells, and in vitro studies have demonstrated that this interaction triggers NF-κB-dependent epithelial cell responses. However, the contribution of respiratory epithelial cells to the normal host response to Pneumocystis remains unknown. IκB kinase 2 (IKK2) is the upstream kinase that is critical for inducible NF-κB activation. To determine whether IKK2-dependent lung epithelial cell (LEC) responses contribute to the anti-Pneumocystis immune response in vivo, transgenic mice with LEC-specific deletion of IKK2 (IKK2(ΔLEC)) were generated. Compared to wild-type mice, IKK2(ΔLEC) mice exhibited a delayed onset of Th17 and B cell responses in the lung and delayed fungal clearance. Importantly, delayed Pneumocystis clearance in IKK2(ΔLEC) mice was associated with an exacerbated immune response, impaired pulmonary function, and altered lung histology. These data demonstrate that IKK2-dependent LEC responses are important regulators of pulmonary adaptive immune responses and are required for optimal host defense against Pneumocystis infection. LECs likely set the threshold for initiation of the pulmonary immune response and serve to prevent exacerbated lung inflammation by promoting the rapid control of respiratory fungal infection.
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Affiliation(s)
- Nelissa Perez-Nazario
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642
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B cell production of tumor necrosis factor in response to Pneumocystis murina infection in mice. Infect Immun 2013; 81:4252-60. [PMID: 24002064 DOI: 10.1128/iai.00744-13] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pneumocystis species are opportunistic fungal pathogens that induce tumor necrosis factor (TNF) production by alveolar macrophages. Here we report that B cells from the draining lymph nodes as well as lung CD4(+) T cells are important producers of TNF upon Pneumocystis murina infection. To determine the importance of B cell-derived TNF in the primary response to P. murina, we generated bone marrow chimeras whose B cells were unable to produce TNF. The lung P. murina burden at 10 days postinfection in TNF knockout (TNFKO) chimeras was significantly higher than that in wild-type (WT) chimeras, which corresponded to reduced numbers of activated CD4(+) T cells in the lungs at this early time point. Furthermore, CD4(+) T cells isolated from P. murina-infected TNFKO chimeras were unable to stimulate clearance of P. murina upon adoptive transfer to recombinase-deficient (RAG1KO) hosts. Together, these data indicate that B cell-derived TNF plays an important function in promoting CD4(+) T cell expansion and production of TNF and facilitating protection against P. murina infection.
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Searles S, Gauss K, Wilkison M, Hoyt TR, Dobrinen E, Meissner N. Modulation of inflammasome-mediated pulmonary immune activation by type I IFNs protects bone marrow homeostasis during systemic responses to Pneumocystis lung infection. THE JOURNAL OF IMMUNOLOGY 2013; 191:3884-95. [PMID: 23975863 DOI: 10.4049/jimmunol.1301344] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Although acquired bone marrow failure (BMF) is considered a T cell-mediated autoimmune disease, possible innate immune defects as a cause for systemic immune deviations in response to otherwise innocuous infections have not been extensively explored. In this regard, we recently demonstrated an important role of type I IFNs in protecting hematopoiesis during systemic stress responses to the opportunistic fungal pathogen Pneumocystis in lymphocyte-deficient mice. Mice deficient in both lymphocytes and type I IFN receptor (IFrag(-/-) mice) develop rapidly progressing BMF due to accelerated bone marrow (BM) cell apoptosis associated with innate immune deviations in the BM in response to Pneumocystis lung infection. However, the communication pathway between lung and BM eliciting the induction of BMF in response to this strictly pulmonary infection has been unclear. In this study, we report that absence of an intact type I IFN system during Pneumocystis lung infection not only causes BMF in lymphocyte-deficient mice but also transient BM stress in lymphocyte-competent mice. This is associated with an exuberant systemic IFN-γ response. IFN-γ neutralization prevented Pneumocystis lung infection-induced BM depression in type I IFN receptor-deficient mice and prolonged neutrophil survival time in BM from IFrag(-/-) mice. IL-1β and upstream regulators of IFN-γ, IL-12, and IL-18 were also upregulated in lung and serum of IFrag(-/-) mice. In conjunction, there was exuberant inflammasome-mediated caspase-1 activation in pulmonary innate immune cells required for processing of IL-18 and IL-1β. Thus, absence of type I IFN signaling during Pneumocystis lung infection may result in deregulation of inflammasome-mediated pulmonary immune activation, causing systemic immune deviations triggering BMF in this model.
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Affiliation(s)
- Steve Searles
- Department of Pathology, University of California School of Medicine, La Jolla, CA 92093
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Myers RC, Dunaway CW, Nelson MP, Trevor JL, Morris A, Steele C. STAT4-dependent and -independent Th2 responses correlate with protective immunity against lung infection with Pneumocystis murina. THE JOURNAL OF IMMUNOLOGY 2013; 190:6287-94. [PMID: 23650614 DOI: 10.4049/jimmunol.1300431] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Although it is clear that the loss of CD4(+) T cells is a predisposing factor for the development of Pneumocystis pneumonia, specific Th mechanisms mediating protection are not well understood. Th1, Th2, and Th17 responses have each been implicated in protective responses during infection. As STAT4 may promote Th1 and Th17 development, yet antagonize Th2 development, we investigated its role in Pneumocystis murina host defense. STAT4 was required for Th1 and, unexpectedly, Th2 responses in the lungs of C57BL/6 (BL/6) and BALB/c mice 14 d postchallenge, but only BALB/c Stat4(-/-) mice demonstrated susceptibility to P. murina lung infection. BL/6 Stat4(-/-), but not BALB/c Stat4(-/-), mice maintained an enhanced alternatively activated (M2) macrophage signature in the lungs, which we have previously reported to be associated with enhanced P. murina clearance. In addition, anti-P. murina class-switched Abs were increased in BL/6 Stat4(-/-) mice, but not BALB/c Stat4(-/-) mice. Supporting our experimental observations, plasma from HIV-infected individuals colonized with Pneumocystis jirovecii contained significantly lower levels of the Th2 cytokines IL-4, IL-5, and IL-13 compared with HIV-infected individuals who were not colonized. Collectively, our data suggest that robust local and systemic Th2-mediated responses are critical for immunity to Pneumocystis.
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Affiliation(s)
- Riley C Myers
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Cartin-Ceba R, Golbin JM, Keogh KA, Peikert T, Sánchez-Menéndez M, Ytterberg SR, Fervenza FC, Specks U. Rituximab for remission induction and maintenance in refractory granulomatosis with polyangiitis (Wegener's): ten-year experience at a single center. ACTA ACUST UNITED AC 2013; 64:3770-8. [PMID: 22730028 DOI: 10.1002/art.34584] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE This study was conducted to evaluate the efficacy and safety of repeated and prolonged B cell depletion with rituximab (RTX) for the maintenance of long-term remission in patients with chronic relapsing granulomatosis with polyangiitis (Wegener's) (GPA). METHODS We conducted a single-center observational study of all patients with chronic relapsing GPA treated with at least 2 courses of RTX between January 1, 2000 and May 31, 2010. Participants in the Rituximab in ANCA-Associated Vasculitis (RAVE) trial were excluded from this analysis. Data were abstracted from electronic medical records. RESULTS Fifty-three patients with refractory GPA (median age 46 years [interquartile range (IQR) 30-61 years]; 53% women) received at least 2 courses of RTX to treat GPA relapses or to maintain remission. All but 1 patient had antineutrophil cytoplasmic antibodies (ANCA) against proteinase 3 (PR3). These patients received a median of 4 courses of RTX (IQR 3-5); all had depletion of B cells, and the median time to return of B cells was 8.5 months (IQR 6-11 months). All observed relapses occurred after reconstitution of B cells and were accompanied or preceded by an increase in ANCA levels, except for the 1 ANCA-negative patient. Infusion-related adverse events occurred in 16 patients. During the period of B cell depletion, 30 infections requiring antimicrobial therapy were recorded. CONCLUSION RTX appeared to be effective and safe for the induction and maintenance of remission in patients with chronic relapsing GPA. Repeated depletion of B lymphocytes seems to be associated with a low risk of infections. Preemptive re-treatment decisions can be individualized based on serial B lymphocyte and PR3 ANCA monitoring. The use of RTX for the maintenance of long-term remission merits further formal investigation.
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Abstract
Although the incidence of Pneumocystis pneumonia (PCP) has decreased since the introduction of combination antiretroviral therapy, it remains an important cause of disease in both HIV-infected and non-HIV-infected immunosuppressed populations. The epidemiology of PCP has shifted over the course of the HIV epidemic both from changes in HIV and PCP treatment and prevention and from changes in critical care medicine. Although less common in non-HIV-infected immunosuppressed patients, PCP is now more frequently seen due to the increasing numbers of organ transplants and development of novel immunotherapies. New diagnostic and treatment modalities are under investigation. The immune response is critical in preventing this disease but also results in lung damage, and future work may offer potential areas for vaccine development or immunomodulatory therapy. Colonization with Pneumocystis is an area of increasing clinical and research interest and may be important in development of lung diseases such as chronic obstructive pulmonary disease. In this review, we discuss current clinical and research topics in the study of Pneumocystis and highlight areas for future research.
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Alveolar macrophages in neonatal mice are inherently unresponsive to Pneumocystis murina infection. Infect Immun 2012; 80:2835-46. [PMID: 22665378 DOI: 10.1128/iai.05707-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Pneumocystis pneumonia was first diagnosed in malnourished children and has more recently been found in children with upper respiratory symptoms. We previously reported that there is a significant delay in the immune response in newborn mice infected with Pneumocystis compared to adults (Garvy BA, Harmsen AG, Infect. Immun. 64:3987-3992, 1996, and Garvy BA, Qureshi M, J. Immunol. 165:6480-6486, 2000). This delay is characterized by the failure of neonatal lungs to upregulate proinflammatory cytokines and attract T cells into the alveoli. Here, we report that regardless of the age at which we infected the mice, they failed to mount an inflammatory response in the alveolar spaces until they were 21 days of age or older. Anti-inflammatory cytokines had some role in dampening inflammation, since interleukin-10 (IL-10)-deficient pups cleared Pneumocystis faster than wild-type pups and the neutralization of transforming growth factor beta (TGF-β) with specific antibody enhanced T cell migration into the lungs at later time points. However, the clearance kinetics were similar to those of control pups, suggesting that there is an intrinsic deficiency in the ability of innate immunity to control Pneumocystis. We found, using an adoptive transfer strategy, that the lung environment contributes to association of Pneumocystis organisms with alveolar macrophages, implying no intrinsic deficiency in the binding of Pneumocystis by neonatal macrophages. Using both in vivo and in vitro assays, we found that Pneumocystis organisms were less able to stimulate translocation of NF-κB to the nucleus of alveolar macrophages from neonatal mice. These data indicate that there is an early unresponsiveness of neonatal alveolar macrophages to Pneumocystis infection that is both intrinsic and related to the immunosuppressive environment found in neonatal lungs.
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León B, Ballesteros-Tato A, Misra RS, Wojciechowski W, Lund FE. Unraveling effector functions of B cells during infection: the hidden world beyond antibody production. Infect Disord Drug Targets 2012; 12:213-21. [PMID: 22394173 PMCID: PMC4517595 DOI: 10.2174/187152612800564437] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 02/25/2012] [Indexed: 12/12/2022]
Abstract
Antibodies made by B cells are critically important for immune protection to a variety of infectious agents. However, it is becoming increasingly clear that B cells do more than make antibodies and that B cells can both enhance and suppress immune responses. Furthermore, there is growing evidence that B cells modulate cellular immune responses by antibody dependent and independent mechanisms. Although we have a good understanding of the roles played by antibody- secreting effector B cells during immune responses, we know very little about the Ab independent "effector" functions of B cells in either health or disease. Given the recent data suggesting that B cells may contribute to autoimmune disease pathogenesis via an antibody independent mechanism and the increasing use of B cell depletion therapy in autoimmune patients, investigators are beginning to reassess the multiple roles for B cells during immune responses. In this article, we review data describing how B cells mediate protection to pathogens independently of antibody production. In particular, we will focus on the role that B cells play in facilitating dendritic cell and T cell interactions in lymph nodes, the importance of antigen-presenting B cells in sustaining effector T cell and T follicular helper responses to pathogens and the relevance of cytokine-producing effector and regulatory B cells in immune responses.
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Affiliation(s)
- Beatriz León
- University of Alabama, Dept. of Microbiology, Birmingham, AL 35294-2170, USA
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42
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Abstract
With increases in the immunocompromised patient population and aging of the HIV+ population, the risk of serious fungal infections and their complications will continue to rise. In these populations, infection with the fungal opportunistic pathogen Pneumocystis jirovecii remains a leading cause of morbidity and mortality. Infection with Pneumocystis (Pc) has been shown to be associated with the development of chronic obstructive pulmonary disease (COPD) in human subjects with and without HIV infection and in non-human primate models of HIV infection. In human studies and in a primate model of HIV/Pc co-infection, we have shown that antibody response to the Pc protein, kexin (KEX1), correlates with protection from colonization, Pc pneumonia, and COPD. These findings support the hypothesis that immunity to KEX1 may be critical to controlling Pc colonization and preventing or slowing development of COPD.
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Affiliation(s)
- Karen A Norris
- Department of Immunology, University of Pittsburgh School of Medicine, E 1057 Biomedical Science Tower, Pittsburgh, PA 15261, USA.
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Role of interleukin-23-dependent antifungal immune responses in dendritic cell-vaccinated mice. Infect Immun 2011; 79:3778-83. [PMID: 21746859 DOI: 10.1128/iai.05163-11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
CD40 ligand (CD40L) transduction of antigen-pulsed dendritic cells (DCs) can result in antigen-specific humoral immune responses even in CD4(+) T-cell-depleted settings. Here, we show that CD40L transduction of DCs results in the induction of interleukin-12p40 (IL-12p40), IL-12p70, and IL-23. Using DCs that were deficient in IL-12p40, IL-12p35, or IL-23p19, we show that these molecules are dispensable for primary IgG1 responses to Pneumocystis, but IgG2c was dependent on IL-12p40 and IL-23p19 but not IL-12p35. Antigen-specific recall responses in CD4-deficient mice were critically dependent on IL-12p40 and IL-23p19 expression in DCs and were not affected by the lack of IL-12p35. To confirm that this defect in recall was due to IL-23, transduction of IL-12p40(-/-) DCs with a recombinant adenovirus expressing functional IL-23 restored recall responses in DC-vaccinated CD4-deficient mice. These data show that DC-produced IL-23 is critical for vaccine-induced antigen-specific IgG2c and recall antibody responses in the setting of CD4(+) T-cell depletion.
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Barr TA, Brown S, Mastroeni P, Gray D. TLR and B cell receptor signals to B cells differentially program primary and memory Th1 responses to Salmonella enterica. THE JOURNAL OF IMMUNOLOGY 2010; 185:2783-9. [PMID: 20675594 DOI: 10.4049/jimmunol.1001431] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Protective Th1 responses to Salmonella enterica do not develop in the absence of B cells. Using chimeric mice, we dissect the early (innate) and late (cognate) contributions of B cells to Th programming. B cell-intrinsic MyD88 signaling is required for primary effector Th1 development, whereas Ag-specific BCR-mediated Ag presentation is necessary for the development of memory Th1 populations. Programming of the primary T cell response is BCR/B cell MHC II independent, but requires MyD88-dependent secretion of cytokines by B cells. Chimeras in which B cells lack IFN-gamma or IL-6 genes make impaired Th1 or Th17 responses to Salmonella.
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Affiliation(s)
- Tom A Barr
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
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Relationship of Pneumocystis jiroveci humoral immunity to prevention of colonization and chronic obstructive pulmonary disease in a primate model of HIV infection. Infect Immun 2010; 78:4320-30. [PMID: 20660609 DOI: 10.1128/iai.00507-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Pulmonary colonization by the opportunistic pathogen Pneumocystis jiroveci is common in HIV(+) subjects and has been associated with development of chronic obstructive pulmonary disease (COPD). Host and environmental factors associated with colonization susceptibility are undefined. Using a simian-human immunodeficiency virus (SHIV) model of HIV infection, the immunologic parameters associated with natural Pneumocystis jiroveci transmission were evaluated. SHIV-infected macaques were exposed to P. jiroveci by cohousing with immunosuppressed, P. jiroveci-colonized macaques in two independent experiments. Serial plasma and bronchoalveolar lavage (BAL) fluid samples were examined for changes in antibody titers to recombinant Pneumocystis-kexin protein (KEX1) and evidence of Pneumocystis colonization by nested PCR of BAL fluid. In experiment 1, 10 of 14 monkeys became Pneumocystis colonized (Pc(+)) by 8 weeks post-SHIV infection, while 4 animals remained Pneumocystis colonization negative (Pc(-)) throughout the study. In experiment 2, 11 of 17 animals became Pneumocystis colonized by 16 weeks post-SHIV infection, while 6 monkeys remained Pc(-). Baseline plasma KEX1-IgG titers were significantly higher in monkeys that remained Pc(-), compared to Pc(+) monkeys, in experiments 1 (P = 0.013) and 2 (P = 0.022). Pc(-) monkeys had greater percentages of Pneumocystis-specific memory B cells after SHIV infection compared to Pc(+) monkeys (P = 0.037). After SHIV infection, Pc(+) monkeys developed progressive obstructive pulmonary disease, whereas Pc(-) monkeys maintained normal lung function throughout the study. These results demonstrate a correlation between the KEX1 humoral response and the prevention of Pneumocystis colonization and obstructive lung disease in the SHIV model. In addition, these results indicate that an effective Pneumocystis-specific memory B-cell response is maintained despite progressive loss of CD4(+) T cells during SHIV infection.
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Abstract
After more than 10 years of use, rituximab has proven to be remarkably safe. However, accumulated evidence now suggests that under some circumstances it may significantly increase the risk of infections. This risk is difficult to quantify because of confounding factors (namely, concomitant use of immunosuppressive or chemotherapeutic agents and underlying conditions), as well as under-reporting. Increased number of infections has been documented in patients treated with maintenance rituximab for low-grade lymphoma and in patients with concomitant severe immunodeficiency, whether caused by human immunodeficiency virus (HIV) infection or immunosuppressive agents like fludarabine. From the practical standpoint, the most important infection is hepatitis B reactivation, which may be delayed and result in fulminant liver failure and death. Special care should be placed on screening for hepatitis B virus (HBV) and preemptive antiviral treatment. Some investigators have reported an increase in Pneumocystis pneumonia. Finally, there is increasing evidence of a possible association with progressive multifocal leukoencephalopathy (PML), a lethal encephalitis caused by the polyomavirus JC. This review enumerates the described infectious complications, summarizes the possible underlying mechanisms of the increased risk, and makes recommendations regarding prevention, diagnosis and management.
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Affiliation(s)
- Juan C Gea-Banacloche
- Experimental Transplantation and Immunology Branch, National Cancer Institute, Bethesda, MD 20892, USA.
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47
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Hugle B, Solomon M, Harvey E, James A, Wadhwa A, Amin R, Bell-Peter A, Benseler S. Pneumocystis jiroveci pneumonia following rituximab treatment in Wegener's granulomatosis. Arthritis Care Res (Hoboken) 2010; 62:1661-4. [PMID: 20583109 DOI: 10.1002/acr.20279] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 06/17/2010] [Indexed: 11/09/2022]
Affiliation(s)
- Boris Hugle
- The Hospital for Sick Children, University of Toronto, Ontario, Canada
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48
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Abstract
Pneumocystis jirovecii is the opportunistic fungal organism that causes Pneumocystis pneumonia (PCP) in humans. Similar to other opportunistic pathogens, Pneumocystis causes disease in individuals who are immunocompromised, particularly those infected with HIV. PCP remains the most common opportunistic infection in patients with AIDS. Incidence has decreased greatly with the advent of HAART. However, an increase in the non-HIV immunocompromised population, noncompliance with current treatments, emergence of drug-resistant strains and rise in HIV(+) cases in developing countries makes Pneumocystis a pathogen of continued interest and a public health threat. A great deal of research interest has addressed therapeutic interventions to boost waning immunity in the host to prevent or treat PCP. This article focuses on research conducted during the previous 5 years regarding the host immune response to Pneumocystis, including innate, cell-mediated and humoral immunity, and associated immunotherapies tested against PCP.
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Affiliation(s)
- Michelle N Kelly
- Section of Pulmonary/Critical Care Medicine, LSU Health Sciences Center, Medical Education Building 3205, 1901 Perdido Street, New Orleans, LA 70112, USA.
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49
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Zarkhin V, Chalasani G, Sarwal MM. The yin and yang of B cells in graft rejection and tolerance. Transplant Rev (Orlando) 2010; 24:67-78. [PMID: 20149626 DOI: 10.1016/j.trre.2010.01.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Various lineages of B cells are being increasingly recognized as important players in the etiology and prognosis of both acute and chronic graft rejection. The role of immature, chronically activated B cells, as efficient antigen-presenting cells, supporting recalcitrant cell-mediated graft rejection and late lineage B cells driving humoral rejections, is being increasingly recognized. This review captures the recent literature on this subject and discusses the various roles of the B cell in renal graft rejection and conversely, also in graft tolerance, both in animal and human studies. In addition, novel therapies targeting specific B-cell lineages in graft rejection are also discussed, with a view to developing more targeted therapies for graft rejection.
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Affiliation(s)
- Valeriya Zarkhin
- Department of Pediatrics, Stanford University, Stanford, CA, USA.
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50
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Abstract
Pneumocystis pneumonia (PCP) is a life-threatening infection in immunocompromised children with quantitative and qualitative defects in T lymphocytes. At risk are children with lymphoid malignancies, HIV infection, corticosteroid therapy, transplantation and primary immunodeficiency states. Diagnosis is established through direct examination or polymerase chain reaction (PCR) from respiratory secretions. Trimethoprim-sulphamethoxazole is used for initial therapy in most patients, while pentamidine, atovaquone, clindamycin plus primaquine, and dapsone plus trimethoprim are alternatives. Prophylaxis of high-risk patients reduces but does not eliminate the risk of PCP. Improved understanding of the pathogenesis of PCP is important for future advances against this life-threatening infection.
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Affiliation(s)
- Vasilios Pyrgos
- Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD 20892, USA.
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