1
|
Khatun M, Islam A, Baek BK. Comparative Analysis of Humoral Immune Response and Cognate Antigen Detection in Experimentally Infected Sprague Dawley Rats with Brucella abortus Biotype 1. Vector Borne Zoonotic Dis 2024; 24:27-35. [PMID: 37955673 DOI: 10.1089/vbz.2023.0021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023] Open
Abstract
Background: This study investigated the IgG-specific humoral immune responses against specific antigen-like whole-cell antigen (WCA), outer membrane protein (OMP), periplasmic protein (PP), and cytoplasmic protein (CP) during the acute and subacute stages of Brucella abortus biotype 1 infection in Sprague Dawley (SD) rats. Materials and Methods: The intraperitoneal method was used to experimentally infect forty-four 6- to 8-week-old SD rats with 1 × 109 colony-forming units (CFUs) of B. abortus biotype 1. Following inoculation, the rat was serially sampled for serum at 0, 3, 7, 14, 21, 28, 35, 42, 60, 90, and 120 days. The IgG-specific immune responses and recognition of immunodominant antigens in WCA, OMP, PP, and CP of B. abortus were assessed by indirect enzyme-linked immunosorbent assay (IELISA) and western blot (WB) assay using infected rat sera. Results: The IgG antibody response was detectable at 3 days after infection. The peak serum IgG antibody titers were recorded against CP and PP at 28 days after infection. The highest serum IgG antibody titers were recorded at 42 days after infection against WCA and 90 days after infection only against OMP. WB assay revealed a wide array of protein bands between molecular weight of 13 and 95 kDa for WCA, 13 and 95 kDa for OMP, 15 and 65 kDa for PP, and 12 and 85 kDa for CP. Proteins bands of 10, 13, 20, 24, 46, and 76 kDa for WCA; 28, 35, 39, 85, and 95 for OMP; 20, 30, 40, 43, 46, and 65 kDa for PP, and 12, 23, 68, and 85 for CP were intensely recognized. Conclusion: Data of this study indicated that WCA, CP, and PP of B. abortus could be useful for diagnosis of acute and subacute brucellosis in SD rat model. OMP of B. abortus could be useful for differential diagnosis of subacute brucellosis.
Collapse
Affiliation(s)
- Minara Khatun
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Ariful Islam
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea
- Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Byeong Kirl Baek
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea
| |
Collapse
|
2
|
Tang Y, Ma C, Sun H, Yang S, Yu F, Li X, Wang L. Serum Levels of Seven General Cytokines in Acute Brucellosis Before and After Treatment. Infect Drug Resist 2021; 14:5501-5510. [PMID: 34955644 PMCID: PMC8694408 DOI: 10.2147/idr.s341331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/02/2021] [Indexed: 01/02/2023] Open
Abstract
Purpose Human brucellosis is the most common bacterial zoonosis globally that poses a severe health threat. Despite the availability of antibiotic therapy for human brucellosis, its tendencies of chronicity and persistence may lead to severe debilitating and disabling conditions in patients. Comprehensive understanding of the immune response in brucellosis will be helpful in improving the treatment strategies. In this study, we measured serum levels of T helper cell type 1 (Th1), Th2, and Th17 cytokines in patients with acute brucellosis before and after treatment. Patients and Methods Overall, 30 patients with acute brucellosis from the Beijing Di Tan Hospital and 26 healthy controls were enrolled in this study. All the patients received a 6-week therapy regimen comprising ceftriaxone, doxycycline, and rifampicin. Serum samples were collected from patients with acute Brucella infection and healthy controls before and after treatment. Serum seven cytokine levels of Th1 (IL-2, IFN-γ, and TNF-α), Th2 (IL-4, IL-6, IL-10), and Th17 (IL-17A) were measured using cytometric bead array. Results In patients with acute infection, the IL-2, IFN-γ, and IL-10 levels were significantly increased compared with those in healthy controls (P < 0.001). After treatment, IL-2, IFN-γ, and IL-10 levels significantly decreased (P < 0.05) and the TNF-α level significantly increased compared with the corresponding baseline levels and those in healthy controls (P < 0.05). Furthermore, the IFN-γ, IL-4, and IL-10 levels were higher in patients after treatment than in healthy controls (P < 0.05). IL-2 and IL-6 levels exhibited a positive correlation with the C-reactive protein (CRP) level in acute brucellosis (P < 0.05). Conclusion Levels of most serum Th1 and Th2 cytokines were simultaneously increased in acute infection, followed by reduction in the corresponding cytokine levels and residual cytokine response during treatment. This residual immune response could represent a therapeutic opportunity that may improve the long-term clinical outcomes in patients with acute brucellosis after treatment.
Collapse
Affiliation(s)
- Yunxia Tang
- Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.,Clinical Center for HIV/AIDS, Capital Medical University, Beijing, People's Republic of China
| | - Chenjie Ma
- Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.,Clinical Center for HIV/AIDS, Capital Medical University, Beijing, People's Republic of China
| | - Huali Sun
- Department of Infectious Diseases, The Affiliated Hospital of Qingdao University, Qingdao, People's Republic of China
| | - Siyuan Yang
- Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.,Clinical Center for HIV/AIDS, Capital Medical University, Beijing, People's Republic of China
| | - Fengting Yu
- Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.,Clinical Center for HIV/AIDS, Capital Medical University, Beijing, People's Republic of China
| | - Xingwang Li
- Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.,Clinical Center for HIV/AIDS, Capital Medical University, Beijing, People's Republic of China
| | - Linghang Wang
- Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.,Clinical Center for HIV/AIDS, Capital Medical University, Beijing, People's Republic of China
| |
Collapse
|
3
|
Stranahan LW, Arenas-Gamboa AM. When the Going Gets Rough: The Significance of Brucella Lipopolysaccharide Phenotype in Host-Pathogen Interactions. Front Microbiol 2021; 12:713157. [PMID: 34335551 PMCID: PMC8319746 DOI: 10.3389/fmicb.2021.713157] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/22/2021] [Indexed: 01/18/2023] Open
Abstract
Brucella is a facultatively intracellular bacterial pathogen and the cause of worldwide zoonotic infections, infamous for its ability to evade the immune system and persist chronically within host cells. Despite the frequent association with attenuation in other Gram-negative bacteria, a rough lipopolysaccharide phenotype is retained by Brucella canis and Brucella ovis, which remain fully virulent in their natural canine and ovine hosts, respectively. While these natural rough strains lack the O-polysaccharide they, like their smooth counterparts, are able to evade and manipulate the host immune system by exhibiting low endotoxic activity, resisting destruction by complement and antimicrobial peptides, entering and trafficking within host cells along a similar pathway, and interfering with MHC-II antigen presentation. B. canis and B. ovis appear to have compensated for their roughness by alterations to their outer membrane, especially in regards to outer membrane proteins. B. canis, in particular, also shows evidence of being less proinflammatory in vivo, suggesting that the rough phenotype may be associated with an enhanced level of stealth that could allow these pathogens to persist for longer periods of time undetected. Nevertheless, much additional work is required to understand the correlates of immune protection against the natural rough Brucella spp., a critical step toward development of much-needed vaccines. This review will highlight the significance of rough lipopolysaccharide in the context of both natural disease and host–pathogen interactions with an emphasis on natural rough Brucella spp. and the implications for vaccine development.
Collapse
Affiliation(s)
- Lauren W Stranahan
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Angela M Arenas-Gamboa
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| |
Collapse
|
4
|
Khatun MM, Islam MA, Baek BK. In Vitro and In Vivo IFN-γ and IL-10 Measurement in Experimental Brucella abortus Biotype 1 Infection in Sprague-Dawley Rats. Vector Borne Zoonotic Dis 2021; 21:579-585. [PMID: 34077683 DOI: 10.1089/vbz.2020.2738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The immune response to Brucella abortus mainly depends on antigen-specific T cell activation, CD4+ and CD8+ T cells, and Brucella-specific humoral response. Protective immune response against Brucella infection has not been performed in the Sprague-Dawley (SD) rat model. We measured bacterial kinetics in addition to in vivo and in vitro interferon gamma (IFN-γ) and interleukin-10 (IL-10) production against crude Brucella protein in the SD rats at different days of postinfection with B. abortus biotype 1 by indirect enzyme-linked immunosorbent assay. Forty SD rats were inoculated intraperitoneally with 0.1 mL sterile injectable pyrogen-free solution containing 1 × 1010 colony-forming units/mL of B. abortus biotype 1 obtained from cattle in Korea. Four rats were used as uninfected control. Serum IFN-γ level at 3 and 7 days postinfection were significantly higher (p > 0.001) compared with the IL-10 level. On the contrary, serum IL-10 levels were observed significantly higher at 21 and 28 days postinfection compared with the serum IFN-γ levels (p < 0.001). The production of IFN-γ by spleen cells was significantly higher at 7 and 14 days postinfection compared with IL-10 (p < 0.001). On the contrary, IL-10 productions were found to be significantly higher at 21, 28, 35, and 42 days postinfection compared with IFN-γ (p < 0.001). The presence of B. abortus in blood was marked till 5 weeks of infection, throughout the experiment in case of spleen, and no bacteria were isolated from the kidney and liver at 6 weeks postinfection. The in vivo and in vitro IFN-γ and IL-10 measurement in our study reported that B. abortus infection in rats primarily educe T helper (Th)1-dominant immune response in acute infection accompanied by Th2-dominant immune response in chronic infection.
Collapse
Affiliation(s)
- Mst Minara Khatun
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea.,Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Md Ariful Islam
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea.,Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Byeong Kirl Baek
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea
| |
Collapse
|
5
|
Khatun MM, Islam MA, Baek BK. The Profile of Immunoglobulin A and Immunoglobulin G Subclasses in Sprague Dawley Rats Experimentally Infected with Brucella abortus Biotype 1. Vector Borne Zoonotic Dis 2020; 20:358-364. [PMID: 32091978 DOI: 10.1089/vbz.2019.2516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study measured total serum immunoglobulin A (IgA), immunoglobulin G (IgG)1, IgG2a response against whole cell antigen (WCA), outer membrane protein (OMP), periplasmic protein (PP), cytoplasmic protein (CP), and crude Brucella protein (CBP) of Brucella abortus in experimental brucellosis induced with B. abortus biotype 1 in Sprague Dawley (SD) rats during a 17-week infection period. Six- to 8-week-old SD rats (n = 44) were experimentally infected with 1 × 109 colony forming unit of B. abortus biotype 1 through the intraperitoneal route. Serial serum samples were collected from the rat at 0, 3, 7, 14, 21, 28, 35, 42, 60, 90, and 120 days after inoculation. The sera were tested by enzyme linked immunosorbent assay. We have noticed a very low level and short persistence of IgA antibody in our experiment. The low level and short persistence of IgA antibody suggest that this antibody isotype might not be protective against brucellosis in rats. Both Th1 and Th2 specific immune responses were recorded in our study with the production of IgG1 and IgG2a antibody isotopes, respectively. We noticed significant dominant IgG2a antibody responses over IgG1 responses throughout the experiment (p < 0.001) against WCA and OMP. The mixed Th1 and Th2 dominant immune responses mediated by IgG2a and IgG1 antibody isotypes were observed against CP, PP, and CBP. Data of our study suggest that IgG2a dominant responses in the early stages of disease play the main role in conferring protection against brucellosis and with the progress of disease IgG1 dominant responses were elicited.
Collapse
Affiliation(s)
- Mst Minara Khatun
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea.,Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Md Ariful Islam
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea.,Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Byeong Kirl Baek
- Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju, Republic of Korea
| |
Collapse
|
6
|
Stranahan LW, Khalaf OH, Garcia-Gonzalez DG, Arenas-Gamboa AM. Characterization of Brucella canis infection in mice. PLoS One 2019; 14:e0218809. [PMID: 31220185 PMCID: PMC6586350 DOI: 10.1371/journal.pone.0218809] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/10/2019] [Indexed: 01/18/2023] Open
Abstract
Canine brucellosis, caused by Brucella canis, is a disease of dogs and represents a public health concern as it can be transmitted to humans. Canine brucellosis is on the rise in the United States and there is currently no vaccine for use in dogs. Mice have been extensively utilized to investigate host-pathogen interactions and vaccine candidates for smooth Brucella species and could serve a similar role for studying B. canis. However, comparatively little is known about B. canis infection in mice. The objective of this study was to characterize the kinetics of colonization and pathogenicity of B. canis in mice in order to evaluate the mouse as a model for studying this pathogen. C57BL/6 mice were inoculated intraperitoneally with 105, 107, or 109 CFU of Brucella canis RM6/66 and euthanized 1-, 2-, 4-, 6-, 9-, and 12-weeks post-inoculation. B. canis induced splenomegaly in mice infected with 109 CFU at 1- and 2 weeks post-inoculation while no gross lesions were observed in other dose groups. Infection at the two higher doses resulted in dose-dependent granulomatous hepatitis and histiocytic infiltration of the spleen and mesenteric lymph nodes by 1-2 weeks. B. canis was cultured from the liver, spleen, uterus, bone marrow, lung, and kidney in all groups with colonization declining at a slow but steady rate throughout the experiment. Clearance was achieved by 9 weeks 105 CFU group and by 12 weeks in the 107 CFU group, while B. canis persisted in the spleen until 12 weeks in the highest dose group. Although B. canis does not demonstrate significant replication in C57BL/6 mice, it has the ability to establish an infection, induce splenomegaly, and persist for several weeks in multiple organs. Moreover, 1 x 107 CFU appears to be a suitable challenge dose for investigating vaccine safety.
Collapse
Affiliation(s)
- Lauren W. Stranahan
- Department of Veterinary Pathobiology, Texas A&M University, College of Veterinary Medicine, College Station, TX, United States of America
| | - Omar H. Khalaf
- Department of Veterinary Pathobiology, Texas A&M University, College of Veterinary Medicine, College Station, TX, United States of America
- Department of Veterinary Pathology & Poultry Diseases, College of Veterinary Medicine, University of Baghdad, Baghdad, Iraq
| | - Daniel G. Garcia-Gonzalez
- Department of Veterinary Pathobiology, Texas A&M University, College of Veterinary Medicine, College Station, TX, United States of America
| | - Angela M. Arenas-Gamboa
- Department of Veterinary Pathobiology, Texas A&M University, College of Veterinary Medicine, College Station, TX, United States of America
- * E-mail:
| |
Collapse
|
7
|
Pujol M, Borie C, Montoya M, Ferreira A, Vernal R. Brucella canis induces canine CD4 + T cells multi-cytokine Th1/Th17 production via dendritic cell activation. Comp Immunol Microbiol Infect Dis 2018; 62:68-75. [PMID: 30711049 DOI: 10.1016/j.cimid.2018.11.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/23/2018] [Accepted: 11/27/2018] [Indexed: 01/18/2023]
Abstract
Brucella canis is a small intracellular Gram-negative bacterium that frequently leads to chronic infections highly resistant to antibiotic therapy in dogs. Also, it causes mild human brucellosis compared to other zoonotic Brucella spp. Herein we characterize the cellular immune response elicited by B. canis by analysing human and canine CD4+ T cells after stimulation with autologous monocyte-derived dendritic cells (MoDCs). Human and canine B. canis-primed MoDCs stimulated autologous CD4+ T cells; however, a Th1 response was triggered by human MoDCs, whereas canine MoDCs induced Th1/Th17 responses, with increased CD4+ T cells producing IFN-γ and IL-17A simultaneously. Each pattern of cellular response may contribute to host susceptibility, helping to understand the differences in B. canis virulence between these two hosts. In addition, other aspects of canine immunology are unveiled by highlighting the participation of IL-17A-producing canine MoDCs and CD4+ T cells producing IFN-γ and IL-17A.
Collapse
Affiliation(s)
- Myriam Pujol
- Program of Immunology, Institute of Biomedical Sciences ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile; Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
| | - Consuelo Borie
- Laboratory of Veterinary Bacteriology, Department of Animal Preventive Medicine, Faculty of Veterinary Sciences, Universidad de Chile, Santiago, Chile
| | - María Montoya
- Centro de Investigaciones Biológicas (CIB), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Arturo Ferreira
- Program of Immunology, Institute of Biomedical Sciences ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.
| | - Rolando Vernal
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile; Dentistry Unit, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile.
| |
Collapse
|
8
|
Murray MA, Chotirmall SH. The Impact of Immunosenescence on Pulmonary Disease. Mediators Inflamm 2015; 2015:692546. [PMID: 26199462 PMCID: PMC4495178 DOI: 10.1155/2015/692546] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 06/09/2015] [Indexed: 01/09/2023] Open
Abstract
The global population is aging with significant gains in life expectancy particularly in the developed world. Consequently, greater focus on understanding the processes that underlie physiological aging has occurred. Key facets of advancing age include genomic instability, telomere shortening, epigenetic changes, and declines in immune function termed immunosenescence. Immunosenescence and its associated chronic low grade systemic "inflamm-aging" contribute to the development and progression of pulmonary disease in older individuals. These physiological processes predispose to pulmonary infection and confer specific and unique clinical phenotypes observed in chronic respiratory disease including late-onset asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis. Emerging concepts of the gut and airway microbiome further complicate the interrelationship between host and microorganism particularly from an immunological perspective and especially so in the setting of immunosenescence. This review focuses on our current understanding of the aging process, immunosenescence, and how it can potentially impact on various pulmonary diseases and the human microbiome.
Collapse
Affiliation(s)
- Michelle A. Murray
- Department of Respiratory Medicine, Mater Misericordiae Hospital, Eccles Street, Dublin 7, Ireland
| | - Sanjay H. Chotirmall
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232
| |
Collapse
|
9
|
Sohal RS, Forster MJ. Caloric restriction and the aging process: a critique. Free Radic Biol Med 2014; 73:366-82. [PMID: 24941891 PMCID: PMC4111977 DOI: 10.1016/j.freeradbiomed.2014.05.015] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/16/2014] [Accepted: 05/17/2014] [Indexed: 01/06/2023]
Abstract
The main objective of this review is to provide an appraisal of the current status of the relationship between energy intake and the life span of animals. The concept that a reduction in food intake, or caloric restriction (CR), retards the aging process, delays the age-associated decline in physiological fitness, and extends the life span of organisms of diverse phylogenetic groups is one of the leading paradigms in gerontology. However, emerging evidence disputes some of the primary tenets of this conception. One disparity is that the CR-related increase in longevity is not universal and may not even be shared among different strains of the same species. A further misgiving is that the control animals, fed ad libitum (AL), become overweight and prone to early onset of diseases and death, and thus may not be the ideal control animals for studies concerned with comparisons of longevity. Reexamination of body weight and longevity data from a study involving over 60,000 mice and rats, conducted by a National Institute on Aging-sponsored project, suggests that CR-related increase in life span of specific genotypes is directly related to the gain in body weight under the AL feeding regimen. Additionally, CR in mammals and "dietary restriction" in organisms such as Drosophila are dissimilar phenomena, albeit they are often presented to be the very same. The latter involves a reduction in yeast rather than caloric intake, which is inconsistent with the notion of a common, conserved mechanism of CR action in different species. Although specific mechanisms by which CR affects longevity are not well understood, existing evidence supports the view that CR increases the life span of those particular genotypes that develop energy imbalance owing to AL feeding. In such groups, CR lowers body temperature, rate of metabolism, and oxidant production and retards the age-related pro-oxidizing shift in the redox state.
Collapse
Affiliation(s)
- Rajindar S Sohal
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA.
| | - Michael J Forster
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| |
Collapse
|
10
|
Interleukin-17A genetic variants can confer resistance to brucellosis in Iranian population. Cytokine 2013; 61:297-303. [DOI: 10.1016/j.cyto.2012.10.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 10/06/2012] [Accepted: 10/12/2012] [Indexed: 01/24/2023]
|
11
|
Active evasion of CTL mediated killing and low quality responding CD8+ T cells contribute to persistence of brucellosis. PLoS One 2012; 7:e34925. [PMID: 22558103 PMCID: PMC3338818 DOI: 10.1371/journal.pone.0034925] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 03/09/2012] [Indexed: 02/02/2023] Open
Abstract
Brucellosis is a common zoonotic disease that remains endemic in many parts of the world. Dissecting the host immune response during this disease provides insight as to why brucellosis is often difficult to resolve. We used a Brucella epitope specific in vivo killing assay to investigate the ability of CD8+ T cells to kill targets treated with purified pathogenic protein. Importantly, we found the pathogenic protein TcpB to be a novel effector of adaptive immune evasion by inhibiting CD8+ T cell killing of Brucella epitope specific target cells in mice. Further, BALB/c mice show active Brucella melitensis infection beyond one year, many with previously unreported focal infection of the urogenital area. A fraction of CD8+ T cells show a CD8+ Tmem phenotype of LFA-1hi, CD127hi, KLRG-1lo during the course of chronic brucellosis, while the CD8+ T cell pool as a whole had a very weak polyfunctional cytokine response with diminished co-expression of IFN-γ with TNFα and/or IL-2, a hallmark of exhaustion. When investigating the expression of these 3 cytokines individually, we observed significant IFN-γ expression at 90 and 180 days post-infection. TNFα expression did not significantly exceed or fall below background levels at any time. IL-2 expression did not significantly exceeded background, but, interestingly, did fall significantly below that of uninfected mice at 180 days post-infection. Brucella melitensis evades and blunts adaptive immunity during acute infection and our findings provide potential mechanisms for the deficit observed in responding CD8+ T cells during chronic brucellosis.
Collapse
|
12
|
Grilló MJ, Blasco JM, Gorvel JP, Moriyón I, Moreno E. What have we learned from brucellosis in the mouse model? Vet Res 2012; 43:29. [PMID: 22500859 PMCID: PMC3410789 DOI: 10.1186/1297-9716-43-29] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 04/13/2012] [Indexed: 01/18/2023] Open
Abstract
Brucellosis is a zoonosis caused by Brucella species. Brucellosis research in natural hosts is often precluded by practical, economical and ethical reasons and mice are widely used. However, mice are not natural Brucella hosts and the course of murine brucellosis depends on bacterial strain virulence, dose and inoculation route as well as breed, genetic background, age, sex and physiological statu of mice. Therefore, meaningful experiments require a definition of these variables. Brucella spleen replication profiles are highly reproducible and course in four phases: i), onset or spleen colonization (first 48 h); ii), acute phase, from the third day to the time when bacteria reach maximal numbers; iii), chronic steady phase, where bacterial numbers plateaus; and iv), chronic declining phase, during which brucellae are eliminated. This pattern displays clear physiopathological signs and is sensitive to small virulence variations, making possible to assess attenuation when fully virulent bacteria are used as controls. Similarly, immunity studies using mice with known defects are possible. Mutations affecting INF-γ, TLR9, Myd88, Tγδ and TNF-β favor Brucella replication; whereas IL-1β, IL-18, TLR4, TLR5, TLR2, NOD1, NOD2, GM-CSF, IL/17r, Rip2, TRIF, NK or Nramp1 deficiencies have no noticeable effects. Splenomegaly development is also useful: it correlates with IFN-γ and IL-12 levels and with Brucella strain virulence. The genetic background is also important: Brucella-resistant mice (C57BL) yield lower splenic bacterial replication and less splenomegaly than susceptible breeds. When inoculum is increased, a saturating dose above which bacterial numbers per organ do not augment, is reached. Unlike many gram-negative bacteria, lethal doses are large (≥ 108 bacteria/mouse) and normally higher than the saturating dose. Persistence is a useful virulence/attenuation index and is used in vaccine (Residual Virulence) quality control. Vaccine candidates are also often tested in mice by determining splenic Brucella numbers after challenging with appropriate virulent brucellae doses at precise post-vaccination times. Since most live or killed Brucella vaccines provide some protection in mice, controls immunized with reference vaccines (S19 or Rev1) are critical. Finally, mice have been successfully used to evaluate brucellosis therapies. It is concluded that, when used properly, the mouse is a valuable brucellosis model.
Collapse
Affiliation(s)
- María-Jesús Grilló
- Instituto de Agrobiotecnología, CSIC-UPNA-Gobierno de Navarra, Pamplona, Spain
| | - José María Blasco
- Centro de Investigación y Tecnología Agroalimentaria (CITA) de Aragón, Zaragoza, Spain
| | - Jean Pierre Gorvel
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Faculté de Sciences de Luminy, Luminy, France
- Institut National de la Santé et de la Recherche Médicale U631, Marseille, France
- Centre National de la Recherche Scientifique UMR6102, Marseille, France
| | - Ignacio Moriyón
- Departamento de Microbiología y Parasitología, Universidad de Navarra, Pamplona, Spain
- Instituto de Salud Tropical, Universidad de Navarra, Pamplona, Spain
| | - Edgardo Moreno
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional, Heredia, Costa Rica
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| |
Collapse
|
13
|
Swindell WR. Dietary restriction in rats and mice: a meta-analysis and review of the evidence for genotype-dependent effects on lifespan. Ageing Res Rev 2012; 11:254-70. [PMID: 22210149 PMCID: PMC3299887 DOI: 10.1016/j.arr.2011.12.006] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 12/06/2011] [Indexed: 01/20/2023]
Abstract
Laboratory survival experiments have shown that dietary restriction (DR) can increase median and maximum lifespan. This paper provides a meta-analysis of laboratory experiments that have evaluated the effects of DR on lifespan in rats and mice (1934-present). In rats, DR increased median lifespan by 14-45% in half of all experiments, but in mice the effects of DR have been much weaker (4-27%). The least favorable effects of DR on lifespan have been observed among inbred rather than non-inbred mouse strains. In fact, some inbred mouse strains do not necessarily live longer with DR, including DBA/2 male mice and several strains from the ILSXISS recombinant inbred panel. Shortening of lifespan with DR has also been observed and confirmed for ILSXISS strain 114. Importantly, all rodent studies may be biased by the effects of laboratory breeding, since one study has shown that median lifespan is not improved by DR in wild-derived mice. These findings suggest that the set of genetic backgrounds studied in rodent DR experiments should be diversified. This will broaden the scope of genotypes studied in aging research, but may also be critical for translation of findings from rodents to historically outbred and genetically heterogeneous primate species.
Collapse
Affiliation(s)
- William R Swindell
- Department of Genetics, Harvard Medical School, Boston, MA 02115, United States.
| |
Collapse
|
14
|
Characterization of outer membrane vesicles from Brucella melitensis and protection induced in mice. Clin Dev Immunol 2011; 2012:352493. [PMID: 22242036 PMCID: PMC3254011 DOI: 10.1155/2012/352493] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 08/29/2011] [Accepted: 09/12/2011] [Indexed: 01/18/2023]
Abstract
The outer membrane vesicles (OMVs) from smooth B. melitensis 16 M and a derived rough mutant, VTRM1 strain, were purified and characterized with respect to protein content and induction of immune responses in mice. Proteomic analysis showed 29 proteins present in OMVs from B. melitensis 16 M; some of them are well-known Brucella immunogens such as SOD, GroES, Omp31, Omp25, Omp19, bp26, and Omp16. OMVs from a rough VTRM1 induced significantly higher expression of IL-12, TNFα, and IFNγ genes in bone marrow dendritic cells than OMVs from smooth strain 16 M. Relative to saline control group, mice immunized intramuscularly with rough and smooth OMVs were protected from challenge with virulent strain B. melitensis 16 M just as well as the group immunized with live strain B. melitensis Rev1 (P < 0.005). Additionally, the levels of serum IgG2a increased in mice vaccinated with OMVs from rough strain VTRM1 consistent with the induction of cell-mediated immunity.
Collapse
|
15
|
Mares CA, Sharma J, Ojeda SS, Li Q, Campos JA, Morris EG, Coalson JJ, Teale JM. Attenuated response of aged mice to respiratory Francisella novicida is characterized by reduced cell death and absence of subsequent hypercytokinemia. PLoS One 2010; 5:e14088. [PMID: 21124895 PMCID: PMC2990712 DOI: 10.1371/journal.pone.0014088] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 10/22/2010] [Indexed: 11/18/2022] Open
Abstract
Background Pneumonia and pulmonary infections are major causes of mortality among the growing elderly population. Age associated attenuations of various immune parameters, involved with both innate and adaptive responses are collectively known as immune senescence. These changes are likely to be involved with differences in host susceptibility to disease between young and aged individuals. Methodology/Principal Findings The objective of this study was to assess potential age related differences in the pulmonary host response in mice to the Gram-negative respiratory pathogen, Francisella novicida. We intranasally infected mice with F. novicida and compared various immune and pathological parameters of the pulmonary host response in both young and aged mice. Conclusions/Significance We observed that 20% of aged mice were able to survive an intranasal challenge with F. novicida while all of their younger cohorts died consistently within 4 to 6 days post infection. Further experiments revealed that all of the aged mice tested were initially able to control bacterial replication in the lungs as well as at distal sites of replication compared with young mice. In addition, the small cohort of aged survivors did not progress to a severe sepsis syndrome with hypercytokinemia, as did all of the young adult mice. Finally, a lack of widespread cell death in potential aged survivors coupled with a difference in cell types recruited to sites of infection within the lung confirmed an altered host response to Francisella in aged mice.
Collapse
Affiliation(s)
- Chris A. Mares
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Jyotika Sharma
- South Texas Center for Emerging Infectious Diseases and Department of Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Sandra S. Ojeda
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Qun Li
- South Texas Center for Emerging Infectious Diseases and Department of Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Jocelyn A. Campos
- South Texas Center for Emerging Infectious Diseases and Department of Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Elizabeth G. Morris
- South Texas Center for Emerging Infectious Diseases and Department of Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Jacqueline J. Coalson
- Department of Pathology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Judy M. Teale
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- South Texas Center for Emerging Infectious Diseases and Department of Biology, The University of Texas at San Antonio, San Antonio, Texas, United States of America
- * E-mail:
| |
Collapse
|
16
|
Busse PJ, Mathur SK. Age-related changes in immune function: effect on airway inflammation. J Allergy Clin Immunol 2010; 126:690-9; quiz 700-1. [PMID: 20920759 DOI: 10.1016/j.jaci.2010.08.011] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Revised: 07/30/2010] [Accepted: 08/05/2010] [Indexed: 12/13/2022]
Abstract
Immunosenescence is defined as changes in the innate and adaptive immune response associated with increased age. The clinical consequences of immunosenescence include increased susceptibility to infection, malignancy and autoimmunity, decreased response to vaccination, and impaired wound healing. However, there are several immune alterations that might facilitate persistence of asthma into late adulthood or development of asthma after the age of 50 to 60 years. Asthma in older patients is not uncommon, and this is a growing population as the average lifespan increases. Specific innate changes that might affect severity of asthma in older patients or be involved in the development of late-onset asthma include impaired mucociliary clearance and changes in airway neutrophil, eosinophil, and mast cell numbers and function. Additionally, age-related altered antigen presentation and decreased specific antibody responses might increase the risk of respiratory tract infections. Respiratory tract infections exacerbate asthma in older patients and possibly play a role in the pathogenesis of late-onset asthma. Furthermore, cytokine profiles might be modified with aging, with some investigators suggesting a trend toward T(H)2 cytokine expression. This review examines specific innate and adaptive immune responses affected by aging that might affect the inflammatory response in older adults with asthma.
Collapse
Affiliation(s)
- Paula J Busse
- Division of Clinical Immunology, Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA.
| | | |
Collapse
|
17
|
Adesiyun AA, Fosgate GT, Seebaransingh R, Brown G, Stoute S, Stewart-Johnson A. Virulence of Brucella abortus isolated from cattle and water buffalo. Trop Anim Health Prod 2010; 43:13-6. [DOI: 10.1007/s11250-010-9679-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2010] [Indexed: 11/24/2022]
|
18
|
Myer RG, El Mezayen R, High KP. Prostaglandin E2-dependent IL-23 production in aged murine dendritic cells. Exp Gerontol 2010; 45:834-41. [PMID: 20600778 DOI: 10.1016/j.exger.2010.06.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 06/10/2010] [Accepted: 06/22/2010] [Indexed: 02/06/2023]
Abstract
CD4+ T cells of the Th17 subtype are over-represented in the aged immune system. Dendritic cells (DC) play a critical role in naïve CD4+ T cell differentiation. However, expression of cytokines by aged DC that promote differentiation or survival of Th17 cells has not been extensively investigated. Using bone marrow-derived DC from C57BL/6 mice of different ages we compared cytokine production after DC activation by Toll-like receptor agonists for TLR4 and/or TLR7/8. DC-derived TNF-α and IL-12p70 production and expression of DC co-stimulatory molecules did not vary significantly by age indicating that TLR expression, function and signal transduction were intact in aged DC. There were relatively minor age-related changes in TGF-β and IL-6 which promote Th17 differentiation, but IL-23, a Th17-suvival cytokine, increased more than 40-fold across the lifespan. DC-derived prostaglandin E2 (PGE2) also increased with age and the up-regulation of IL-23 expression by aged DC was blocked by indomethacin that prevents PGE2 production, and by antagonists of PGE2 receptors. Exogenous PGE2 added to DC cultures further enhanced IL-23 production from aged but not young DCs. These data indicate that age-related changes in DC PGE2 production are necessary, but not sufficient to induce DC IL-23 production. Such changes may play a role in the expansion of Th17 cells in the aged immune system.
Collapse
Affiliation(s)
- Rebecca G Myer
- Department of Internal Medicine, Section of Infectious Diseases, Wake Forest University School of Medicine, 100 Medical Center Blvd., Winston-Salem, NC 27157, USA
| | | | | |
Collapse
|
19
|
Lee SI, Islam MA, Khatun MM, Choi GY, Jung JM, Baek BK, Kakoma I. Immunoglobulin profiles in acute Brucellosis experimentally induced by Brucella canis in BALB/c mice. Vector Borne Zoonotic Dis 2010; 10:927-30. [PMID: 20420532 DOI: 10.1089/vbz.2009.0125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study evaluated profiles of immunoglobulin (Ig; IgA, IgG, IgG1, and IgG2a) response in experimental brucellosis induced with Brucella canis in BALB/c mice during an 8-week infection period. Six- to 8-week-old BALB/c mice (n = 36) were experimentally infected with 1 × 10(9) CFU of B. canis via the intraperitoneal route. Serial serum samples were collected from the mice at 0, 3, 7, 14, 21, 28, 35, 42, 49, and 56 days after inoculation. The sera were tested by the rapid slide agglutination test (RSAT) and 2-mercaptoethanol-RSAT and indirect enzyme-linked immunosorbent assay. Sera tested positive for B. canis by the RSAT and 2-mercaptoethanol-RSAT beginning from 7 days after inoculation until the end of the experiment. The IgA response was detected at 14 days after infection and reached peak levels at 21 days after infection. The IgG antibody responses were detected at 7 days after infection and reached the peak value at 35 days after infection. Data of our study demonstrated IgG2a-dominant responses over IgG1 during the course of infection (p > 0.05).
Collapse
Affiliation(s)
- Sung-Il Lee
- Division of Model Animal, Institute of Biomedical Science, Kansai Medical University, Osaka, Japan
| | | | | | | | | | | | | |
Collapse
|
20
|
Aged mice display an altered pulmonary host response to Francisella tularensis live vaccine strain (LVS) infections. Exp Gerontol 2009; 45:91-6. [PMID: 19825409 DOI: 10.1016/j.exger.2009.10.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 08/27/2009] [Accepted: 10/06/2009] [Indexed: 11/19/2022]
Abstract
Aging is a complex phenomenon that has been shown to affect many organ systems including the innate and adaptive immune systems. The current study was designed to examine the potential effect of immunosenescence on the pulmonary immune response using a Francisella tularensis live vaccine strain (LVS) inhalation infection model. F. tularensis is a Gram-negative intracellular pathogen that can cause a severe pneumonia. In this study both young (8-12 week old) and aged (20-24 month old) mice were infected intranasally with LVS. Lung tissues from young and aged mice were used to assess pathology, recruitment of immune cell types and cytokine expression levels at various times post infection. Bacterial burdens were also assessed. Interestingly, the lungs of aged animals harbored fewer organisms at early time points of infection (day 1, day 3) compared with their younger counterparts. In addition, only aged animals displayed small perivascular aggregates at these early time points that appeared mostly mononuclear in nature. However, the kinetics of infiltrating polymorphonuclear neutrophils (PMNs) and increased cytokine levels measured in the bronchial alveolar lavage fluid (BALF) were delayed in infected aged animals relative to young infected animals with neutrophils appearing at day 5 post infection (PI) in the aged animals as opposed to day 3 PI in the young infected animals. Also evident were alterations in the ratios of mononuclear to PMNs at distinct post infection times. The above evidence indicates that aged mice elicit an altered immune response in the lung to respiratory F. tularensis LVS infections compared to their younger counterparts.
Collapse
|
21
|
El Mezayen R, El Gazzar M, Myer R, High KP. Aging-dependent upregulation of IL-23p19 gene expression in dendritic cells is associated with differential transcription factor binding and histone modifications. Aging Cell 2009; 8:553-65. [PMID: 19624579 DOI: 10.1111/j.1474-9726.2009.00502.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Age-associated changes in immune response increase the risk of infection and promote inflammation and autoimmunity in older adults. The newly discovered cytokine IL-23 contributes to the maintenance and expansion of Th-17 cells, which promote proinflammatory responses. Our preliminary findings suggested that Th-17 responses are increased in aged mice. IL-23 consists of p40 and p19 subunits. Expression of the p19 subunit is regulated at the transcriptional level by NF-kappaB p65 and c-Rel transcription factors. Using bone-marrow-derived dendritic cells (DCs) from C57BL/6 mice, we show that IL-23 protein production and p19 subunit mRNA levels are significantly increased in DCs from aged mice after activation with TLR ligands (LPS + R848) when compared with DCs of young adult mice. We found that the increase in p19 expression in aged cells is associated with chromatin remodeling characterized by di- and tri-methylation of histone H3K4 and binding of mainly c-Rel at the p19 promoter. In young DCs, the promoter is tri-methylated only at H3K4 and bound by both p65 and c-Rel. C-Rel knockdown restores p65 binding in aged cells but does not activate p19 expression, suggesting that c-Rel is critical for p19 expression. In addition, p65 knockdown significantly increases c-Rel binding and p19 expression in young DCs to levels close to those detected in old cells. Furthermore, the decrease in p65 binding at the p19 promoter in old DCs was specific to the p19 gene since p65 binding to the IL-12p40 promoter was not significantly different between old and young DCs. Our results demonstrate that selective changes in H3K4 methylation, and c-Rel and p65 binding at the p19 promoter occur in DCs and contribute to the upregulation of the p19 subunit expression and IL-23 protein production observed in aged mice. This suggests epigenetic and transcriptional mechanisms contribute to dysregulated inflammatory and autoimmune responses associated with aging.
Collapse
Affiliation(s)
- Rabab El Mezayen
- Section of Infectious Diseases, Department of Internal Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
| | | | | | | |
Collapse
|
22
|
Lustig A, Carter A, Bertak D, Enika D, Vandanmagsar B, Wood W, Becker KG, Weeraratna AT, Taub DD. Transcriptome analysis of murine thymocytes reveals age-associated changes in thymic gene expression. Int J Med Sci 2009; 6:51-64. [PMID: 19214242 PMCID: PMC2640475 DOI: 10.7150/ijms.6.51] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Accepted: 02/08/2009] [Indexed: 01/24/2023] Open
Abstract
The decline in adaptive immunity, naïve T-cell output and a contraction in the peripheral T cell receptor (TCR) repertoire with age are largely attributable to thymic involution and the loss of critical cytokines and hormones within the thymic microenvironment. To assess the molecular changes associated with this loss of thymic function, we used cDNA microarray analyses to examine the transcriptomes of thymocytes from mice of various ages ranging from very young (1 month) to very old (24 months). Genes associated with various biological and molecular processes including oxidative phosphorylation, T- and B- cell receptor signaling and antigen presentation were observed to significantly change with thymocyte age. These include several immunoglobulin chains, chemokine and ribosomal proteins, annexin A2, vav 1 and several S100 signaling proteins. The increased expression of immunoglobulin genes in aged thymocytes could be attributed to the thymic B cells which were found to be actively producing IgG and IgM antibodies. Upon further examination, we found that purified thymic T cells derived from aged but not young thymi also exhibited IgM on their cell surface suggesting the possible presence of auto-antibodies on the surface thymocytes with advancing age. These studies provide valuable insight into the cellular and molecular mechanisms associated with thymic aging.
Collapse
Affiliation(s)
- Ana Lustig
- Laboratory of Immunology, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | | | | | | | | | | | | | | | | |
Collapse
|