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Li G, Qiang Y, Li H, Li X, Buffet PA, Dao M, Karniadakis GE. A combined computational and experimental investigation of the filtration function of splenic macrophages in sickle cell disease. PLoS Comput Biol 2023; 19:e1011223. [PMID: 38091361 PMCID: PMC10752522 DOI: 10.1371/journal.pcbi.1011223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 12/27/2023] [Accepted: 11/03/2023] [Indexed: 12/26/2023] Open
Abstract
Being the largest lymphatic organ in the body, the spleen also constantly controls the quality of red blood cells (RBCs) in circulation through its two major filtration components, namely interendothelial slits (IES) and red pulp macrophages. In contrast to the extensive studies in understanding the filtration function of IES, fewer works investigate how the splenic macrophages retain the aged and diseased RBCs, i.e., RBCs in sickle cell disease (SCD). Herein, we perform a computational study informed by companion experiments to quantify the dynamics of RBCs captured and retained by the macrophages. We first calibrate the parameters in the computational model based on microfluidic experimental measurements for sickle RBCs under normoxia and hypoxia, as those parameters are not available in the literature. Next, we quantify the impact of key factors expected to dictate the RBC retention by the macrophages in the spleen, namely, blood flow conditions, RBC aggregation, hematocrit, RBC morphology, and oxygen levels. Our simulation results show that hypoxic conditions could enhance the adhesion between the sickle RBCs and macrophages. This, in turn, increases the retention of RBCs by as much as four-fold, which could be a possible cause of RBC congestion in the spleen of patients with SCD. Our study on the impact of RBC aggregation illustrates a 'clustering effect', where multiple RBCs in one aggregate can make contact and adhere to the macrophages, leading to a higher retention rate than that resulting from RBC-macrophage pair interactions. Our simulations of sickle RBCs flowing past macrophages for a range of blood flow velocities indicate that the increased blood velocity could quickly attenuate the function of the red pulp macrophages on detaining aged or diseased RBCs, thereby providing a possible rationale for the slow blood flow in the open circulation of the spleen. Furthermore, we quantify the impact of RBC morphology on their tendency to be retained by the macrophages. We find that the sickle and granular-shaped RBCs are more likely to be filtered by macrophages in the spleen. This finding is consistent with the observation of low percentages of these two forms of sickle RBCs in the blood smear of SCD patients. Taken together, our experimental and simulation results aid in our quantitative understanding of the function of splenic macrophages in retaining the diseased RBCs and provide an opportunity to combine such knowledge with the current knowledge of the interaction between IES and traversing RBCs to apprehend the complete filtration function of the spleen in SCD.
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Affiliation(s)
- Guansheng Li
- Division of Applied Mathematics, Brown University, Providence, Rhode Island, United States of America
| | - Yuhao Qiang
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - He Li
- School of Chemical, Materials and Biomedical Engineering, University of Georgia, Athens, Georgia, United States of America
| | - Xuejin Li
- Department of Engineering Mechanics and Center for X-Mechanics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Pierre A. Buffet
- Université Paris Cité and Université des Antilles, Inserm, Biologie Intégrée du Globule Rouge, Paris, France
| | - Ming Dao
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - George Em Karniadakis
- Division of Applied Mathematics, Brown University, Providence, Rhode Island, United States of America
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Li G, Qiang Y, Li H, Li X, Buffet PA, Dao M, Karniadakis GE. A combined computational and experimental investigation of the filtration function of splenic macrophages in sickle cell disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.31.543007. [PMID: 37398427 PMCID: PMC10312537 DOI: 10.1101/2023.05.31.543007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Being the largest lymphatic organ in the body, the spleen also constantly controls the quality of red blood cells (RBCs) in circulation through its two major filtration components, namely interendothelial slits (IES) and red pulp macrophages. In contrast to the extensive studies in understanding the filtration function of IES, there are relatively fewer works on investigating how the splenic macrophages retain the aged and diseased RBCs, i.e., RBCs in sickle cell disease (SCD). Herein, we perform a computational study informed by companion experiments to quantify the dynamics of RBCs captured and retained by the macrophages. We first calibrate the parameters in the computational model based on microfluidic experimental measurements for sickle RBCs under normoxia and hypoxia, as those parameters are not available in the literature. Next, we quantify the impact of a set of key factors that are expected to dictate the RBC retention by the macrophages in the spleen, namely, blood flow conditions, RBC aggregation, hematocrit, RBC morphology, and oxygen levels. Our simulation results show that hypoxic conditions could enhance the adhesion between the sickle RBCs and macrophages. This, in turn, increases the retention of RBCs by as much as five-fold, which could be a possible cause of RBC congestion in the spleen of patients with SCD. Our study on the impact of RBC aggregation illustrates a 'clustering effect', where multiple RBCs in one aggregate can make contact and adhere to the macrophages, leading to a higher retention rate than that resulting from RBC-macrophage pair interactions. Our simulations of sickle RBCs flowing past macrophages for a range of blood flow velocities indicate that the increased blood velocity could quickly attenuate the function of the red pulp macrophages on detaining aged or diseased RBCs, thereby providing a possible rationale for the slow blood flow in the open circulation of the spleen. Furthermore, we quantify the impact of RBC morphology on their tendency to be retained by the macrophages. We find that the sickle and granular-shaped RBCs are more likely to be filtered by macrophages in the spleen. This finding is consistent with the observation of low percentages of these two forms of sickle RBCs in the blood smear of SCD patients. Taken together, our experimental and simulation results aid in our quantitative understanding of the function of splenic macrophages in retaining the diseased RBCs and provide an opportunity to combine such knowledge with the current knowledge of the interaction between IES and traversing RBCs to apprehend the complete filtration function of the spleen in SCD.
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Affiliation(s)
- Guansheng Li
- Division of Applied Mathematics, Brown University, Providence, Rhode Island, 02906
| | - Yuhao Qiang
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139
| | - He Li
- School of Chemical, Materials and Biomedical Engineering, University of Georgia, Athens, Georgia, 30602
| | - Xuejin Li
- Department of Engineering Mechanics and Center for X-Mechanics, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Pierre A. Buffet
- Université Paris Cité and Université des Antilles, Inserm, Biologie Intégrée du Globule Rouge, 75015, Paris, France
- Laboratoire d′Excellence du Globule Rouge, 75015, Paris, France
| | - Ming Dao
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139
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Zhai X, Hong T, Zhang T, Xing B, Wang J, Wang X, Miao R, Li T, Wei L. Identification and antiviral effect of Cherry Valley duck IRF4. Poult Sci 2021; 101:101560. [PMID: 34823176 PMCID: PMC8628015 DOI: 10.1016/j.psj.2021.101560] [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: 08/07/2021] [Revised: 09/26/2021] [Accepted: 10/10/2021] [Indexed: 11/24/2022] Open
Abstract
Interferon regulatory factor 4 (IRF4) is a multifunctional transcription factor that plays an important regulatory role in the interferon (IFN) signaling. IRF4 participates in the process of antivirus, Th cell differentiation and B cell maturation by regulating the expression of IFN and some lymphokines. In this study, Cherry Valley duck IRF4 (duIRF4) was cloned and its cDNA was analyzed. Expression of duIRF4 in a wide variety of tissues and changes in duIRF4 expression due to viral infection also was detected by quantitative real-time PCR. The results show that duIRF4 contains 1,341 bp of ORF encoding a protein with 446 amino acids and contains 3 domains: DNA-binding domain (DBD), IRF-association domain (IAD) and nuclear localization signal (NLS). Quantitative real-time PCR analysis showed that duIRF4 was evenly expressed in all tissues examined, with the highest expression in the spleen, followed by the bursa of Fabricius, and lower in the skin and brain. In addition, expression of duIRF4 in the brain and spleen was significantly upregulated after being infected by duck plague virus, duck Tembusu virus, and novel duck reovirus. These data suggest that duIRF4 may be involved in innate immune response.
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Affiliation(s)
- Xinyu Zhai
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Tianqi Hong
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Tingting Zhang
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, College of Basic Medical Sciences, Shandong First Medical University, Tai'an City 271000, Shandong Province, China
| | - Bin Xing
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Jinchao Wang
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Xiuyuan Wang
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Runchun Miao
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Tianxu Li
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China
| | - Liangmeng Wei
- Sino-German Cooperative Research Centre for Zoonosis of Animal Origin of Shandong Province, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City, 271018, Shandong Province, China; Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, College of Basic Medical Sciences, Shandong First Medical University, Tai'an City 271000, Shandong Province, China.
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Li H, Liu ZL, Lu L, Buffet P, Karniadakis GE. How the spleen reshapes and retains young and old red blood cells: A computational investigation. PLoS Comput Biol 2021; 17:e1009516. [PMID: 34723962 PMCID: PMC8584971 DOI: 10.1371/journal.pcbi.1009516] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 11/11/2021] [Accepted: 10/01/2021] [Indexed: 11/18/2022] Open
Abstract
The spleen, the largest secondary lymphoid organ in humans, not only fulfils a broad range of immune functions, but also plays an important role in red blood cell’s (RBC) life cycle. Although much progress has been made to elucidate the critical biological processes involved in the maturation of young RBCs (reticulocytes) as well as removal of senescent RBCs in the spleen, the underlying mechanisms driving these processes are still obscure. Herein, we perform a computational study to simulate the passage of RBCs through interendothelial slits (IES) in the spleen at different stages of their lifespan and investigate the role of the spleen in facilitating the maturation of reticulocytes and in clearing the senescent RBCs. Our simulations reveal that at the beginning of the RBC life cycle, intracellular non-deformable particles in reticulocytes can be biomechanically expelled from the cell upon passage through IES, an insightful explanation of why this peculiar “pitting” process is spleen-specific. Our results also show that immature RBCs shed surface area by releasing vesicles after crossing IES and progressively acquire the biconcave shape of mature RBCs. These findings likely explain why RBCs from splenectomized patients are significantly larger than those from nonsplenectomized subjects. Finally, we show that at the end of their life span, senescent RBCs are not only retained by IES due to reduced deformability but also become susceptible to mechanical lysis under shear stress. This finding supports the recent hypothesis that transformation into a hemolyzed ghost is a prerequisite for phagocytosis of senescent RBCs. Altogether, our computational investigation illustrates critical biological processes in the spleen that cannot be observed in vivo or in vitro and offer insights into the role of the spleen in the RBC physiology. The spleen, the largest secondary lymphoid organ in humans, not only fulfils a broad range of immune functions, but also plays an important role in red blood cell (RBC) life cycle. In this study, we perform a computational study to simulate the passage of RBCs through interendothelial slits (IES) in the spleen at different stages of their lifespan, a critical biological process that cannot be observed in humans. Our simulation results illustrate a specific role of spleen in shaping young RBCs, which points to a probable missing step in current in vitro RBC culture protocols that fail to generate a majority of typical biconcave RBCs. Our results also reveal that intra-splenic mechanical constraints likely contribute to the final clearance and elimination of aged RBCs. Altogether, we demonstrate that our computational model can provide mechanistic rationales for experimental studies, offer insights into the role of the spleen in the RBC physiology and help the optimization of in vitro RBC culture techniques.
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Affiliation(s)
- He Li
- School of Engineering, Brown University, Providence, Rhode Island, United States of America
| | - Zixiang Leonardo Liu
- Division of Applied Mathematics, Brown University, Providence, Rhode Island, United States of America
| | - Lu Lu
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Pierre Buffet
- Université de Paris, Inserm, Biologie Intégrée du Globule Rouge, Paris, France
| | - George Em Karniadakis
- School of Engineering, Brown University, Providence, Rhode Island, United States of America
- Division of Applied Mathematics, Brown University, Providence, Rhode Island, United States of America
- * E-mail:
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Wei YH, He YZ, Guo XY, Lin XY, Zhu HB, Guo XJ. Investigation and Analysis of Iron-Deficiency Anemia Complicated by Splenomegaly. Int J Gen Med 2021; 14:4155-4159. [PMID: 34385835 PMCID: PMC8352643 DOI: 10.2147/ijgm.s324164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/23/2021] [Indexed: 12/29/2022] Open
Abstract
Objective This study aimed to determine the incidence of iron-deficiency anemia (IDA) complicated by splenomegaly in our hospital over the past 6 years and to analyze the possible causes of this result. Methods This is a retrospective study. In total, 668 patients with IDA who were hospitalized in the hematology department of our hospital from 2013 to 2019 were selected as the research subjects and included in the IDA group, and 3201 patients who underwent outpatient physical examinations in our hospital during the same period were included in the control group. The incidences of splenomegaly in the IDA and control groups were calculated, and the difference was analyzed by means of statistical methods. Results Among the 668 IDA patients, 46 (6.9%) had splenomegaly, and among the 3201 patients in the control group, 21 had splenomegaly (0.7%). The incidence of splenomegaly was significantly higher in the IDA group than in the control group, and the severity of anemia in the IDA group was associated with the occurrence of splenomegaly. Specifically, the incidence of splenomegaly was 12.4% among patients with severe anemia and as high as 50% among patients with extremely severe anemia. Conclusion IDA is correlated with the incidence of splenomegaly, and the incidence of splenomegaly significantly increases as the severity of IDA increases. This is considered to be caused by extramedullary hematopoiesis.
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Affiliation(s)
- Yan-Hui Wei
- Department of Graduate School, Xinxiang Medical University, Xinxiang, Henan Province, 453003, People's Republic of China
| | - Yu-Zhuo He
- Department of Hematology, Puyang Oilfield General Hospital, Puyang, Henan Province, 457000, People's Republic of China
| | - Xiao-Yan Guo
- Department of Graduate School, Xinxiang Medical University, Xinxiang, Henan Province, 453003, People's Republic of China
| | - Xiao-Yan Lin
- Department of Hematology, Puyang Oilfield General Hospital, Puyang, Henan Province, 457000, People's Republic of China
| | - Hong-Bin Zhu
- Department of Hematology, Puyang Oilfield General Hospital, Puyang, Henan Province, 457000, People's Republic of China
| | - Xue-Jun Guo
- Department of Hematology, Puyang Oilfield General Hospital, Puyang, Henan Province, 457000, People's Republic of China
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Fan H, Zhang S, Li N, Fan P, Hu X, Liang K, Cheng X, Wu Y. Stable expression ratios of five pyroptosis-inducing cytokines in the spleen and thymus of mice showed potential immune regulation at the organ level. Lupus 2020; 29:290-302. [PMID: 32041506 DOI: 10.1177/0961203320903802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND The immune system is one of the most complex regulatory systems in the body and is essential for the maintenance of homeostasis. Despite recent breakthroughs in immunology, the regulation of the immune system and the etiology of autoimmune diseases such as lupus remain unclear. Systemic lupus erythematosus is a systemic autoimmune disease with abnormally and inconsistently expressed pro-inflammatory cytokines. Pyroptosis is a pro-inflammatory form of programmed cell death that is associated with systemic lupus erythematosus. The thymus and spleen are important immune organs involved in systemic lupus erythematosus. Therefore, this study investigated the difference in expression of pyroptosis-inducing pro-inflammatory cytokines between the spleen and thymus in lupus model mice and in control mice, to describe immune regulation at the organ level. OBJECTIVE To investigate differences in the expression of pyroptosis-inducing cytokines in the spleen and thymus and to explore immune regulatory networks at the organ level. METHODS Two groups of lupus mice and two groups of control mice were utilized for this study. Using the thymus and spleen of experimental animals, mRNA expression levels of five pyroptosis-inducing cytokines (interleukin 1β, interleukin 18, NLRP3, caspase-1 and TNF-α) were determined via quantitative polymerase chain reaction. In addition, tissue distribution of these cytokines was investigated via immunohistochemistry. RESULTS All five pyroptosis-inducing inflammatory cytokines showed higher expression in the spleen than in the thymus (p < 0.05). Moreover, the spleen/thymus expression ratios of all five pyroptosis-inducing cytokines were not statistically different between the four experimental groups. Expression of all five cytokines exhibited a stable ratio (spleen/thymus ratios). This distinctive stable spleen/thymus ratio was consistent in all four experimental groups. The stable spleen/thymus ratios of the five inflammatory cytokines were as follows: interleukin 1β (2.02 ± 0.9), interleukin 18 (2.07 ± 1.06), caspase-1 (1.93 ± 0.66), NLRP3 (3.14 ± 1.61) and TNF-α (3.16 ± 1.36). Immunohistochemical analysis showed the cytokines were mainly expressed in the red pulp region of the spleen and the medullary region of the thymus, where immune-activated cells aggregated. CONCLUSION The stable spleen/thymus expression ratios of pyroptosis-inducing cytokines indicated that immune organs exhibit strictly regulated functions to maintain immune homeostasis and adapt to the environment.
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Affiliation(s)
- H Fan
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - S Zhang
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - N Li
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - P Fan
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - X Hu
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - K Liang
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - X Cheng
- Department of Dermatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Y Wu
- Department of Dermatology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
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Cheng J, Yuan Z, Yang W, Xu C, Cong W, Lin L, Zhao S, Sun W, Bai X, Cui S. Comparative study of macrophages in naked mole rats and ICR mice. Oncotarget 2017; 8:96924-96934. [PMID: 29228582 PMCID: PMC5722534 DOI: 10.18632/oncotarget.19661] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 05/29/2017] [Indexed: 01/30/2023] Open
Abstract
The domestic and foreign scholars have studied naked mole rats more focused on the respect such as its long life, resistant to low oxygen, little spontaneous tumor, but the study of the immune system is little. In this study, we compared the anatomy and tissue morphology of NMR and ICR mouse spleens and found that the gross appearance of the NNMR spleen differed from ICR. There were more macrophages in NNMR spleens than in ICR spleens. Furthermore, we focused on the differences of macrophages. We compared their phagocytic capabilities and the data showed that NNMR macrophages are more phagocytic than ICR mouse macrophages. We also used polyI:C and LPS to stimulate the NMR and ICR macrophages and then measured the immune response as expression of certain TLR signaling molecules. After stimulation, there was a lower increase in apoptosis of NMR macrophages than ICR macrophages and a non-significant increased expression of TLRs in NMR macrophages than in ICR macrophages. In contrast, NF-κB proteins increased more significantly in NMR’s than in ICR’s and the expression of downstream cytokines in NMR macrophages also increased more than in ICR macrophages. Based on these results, we hypothesize that in addition to being able to eat foreign matter, NMR macrophages can activate the TLRs, start the NF-κB and produce a large number of cytokines to enhance immune response, so as to protect the body from outside interference when the virus or bacteria invading.
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Affiliation(s)
- Jishuai Cheng
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
| | - Zheng Yuan
- Department of Science and Technology, Academy of Military Medical Sciences, Beijing, China
| | - Wenjing Yang
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
| | - Chang Xu
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Wei Cong
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
| | - Lifang Lin
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
| | - Shanmin Zhao
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
| | - Wei Sun
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
| | - Xiaosong Bai
- Department of Clinical Laboratory, Shi Dong Hospital, Shanghai, China
| | - Shufang Cui
- Laboratory Animal Centre, Second Military Medical University, Shanghai, China
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McErlean CM, Boult JKR, Collins DJ, Leach MO, Robinson SP, Doran SJ. Detecting microvascular changes in the mouse spleen using optical computed tomography. Microvasc Res 2015; 101:96-102. [PMID: 26142118 PMCID: PMC4542549 DOI: 10.1016/j.mvr.2015.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 11/17/2022]
Abstract
Methods of monitoring drug toxicity in off-target organs are very important in the development of effective and safe drugs. Standard 2-D techniques, such as histology, are prone to sampling errors and can miss important information. We demonstrate a novel application of optical computed tomography (CT) imaging to quantitatively assess, in 3-D, the response of adult murine spleen to off-target drug toxicity induced by treatment with the vascular disrupting agent ZD6126. Reconstructed images from optical CT scans sensitive to haemoglobin absorption reveal detailed, high-contrast 3-D maps of splenic structure and microvasculature. A significant difference in total splenic volume was found between vehicle and ZD6126-treated cohorts, with mean volumes of 61±3mm(3) and 44±3mm(3) respectively (both n=3, p=0.05). Textural statistics for each sample were calculated using grey-level co-occurrence matrices (GLCMs). Standard 2-D GLCM analysis was found to be slice-dependent while 3-D GLCM contrast and homogeneity analysis resulted in separation of the vehicle and ZD6126-treated cohorts over a range of length scales.
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Affiliation(s)
- Ciara M McErlean
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, Sutton SM2 5NG, UK.
| | - Jessica K R Boult
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, Sutton SM2 5NG, UK.
| | - David J Collins
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, Sutton SM2 5NG, UK; Royal Marsden NHS Foundation Trust, Sutton, Surrey SM2 5PT, UK.
| | - Martin O Leach
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, Sutton SM2 5NG, UK; Royal Marsden NHS Foundation Trust, Sutton, Surrey SM2 5PT, UK.
| | - Simon P Robinson
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, Sutton SM2 5NG, UK.
| | - Simon J Doran
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, Sutton SM2 5NG, UK; University of Surrey, Guildford, Surrey GU2 7XH, UK.
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9
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Arora N, Jain S, Inbakumar D, Mammen J, Sitaram U, Nair S. Mean reticulocyte volume enhances the utility of red cell mean sphered cell volume in differentiating peripheral blood spherocytes of hereditary spherocytosis from other causes. INDIAN J PATHOL MICR 2015; 58:307-9. [DOI: 10.4103/0377-4929.162836] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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10
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Souto EB, Müller RH. Lipid nanoparticles: effect on bioavailability and pharmacokinetic changes. Handb Exp Pharmacol 2010:115-41. [PMID: 20217528 DOI: 10.1007/978-3-642-00477-3_4] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The main aim of pharmaceutical technology research is the design of successful formulations for effective therapy, taking into account several issues including therapeutic requirements and patient compliance. In this regard, several achievements have been reported with colloidal carriers, in particular with lipid nanoparticles, due to their unique physicochemical properties. For several years these carriers have been showing potential success for several administration routes, namely oral, dermal, parenteral, and, more recently, for pulmonary and brain targeting. The present chapter provides a review of the use of solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) to modify the release profile and the pharmacokinetic parameters of active pharmaceutical ingredients (APIs) incorporated in these lipid matrices, aiming to modify the API bioavailability, either upwards or downwards depending on the therapeutic requirement. Definitions of the morphological characteristics, surface properties, and polymorphic structures will also be given, emphasizing their influence on the incorporation parameters of the API, such as yield of production, loading capacity, and encapsulation efficiency.
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Affiliation(s)
- Eliana B Souto
- Faculty of Health Sciences, Fernando Pessoa University, Rua Carlos da Maia, 296, P-4200-150, Porto, Portugal.
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11
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Graw F, Regoes RR. Investigating CTL mediated killing with a 3D cellular automaton. PLoS Comput Biol 2009; 5:e1000466. [PMID: 19696876 PMCID: PMC2715871 DOI: 10.1371/journal.pcbi.1000466] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 07/13/2009] [Indexed: 11/25/2022] Open
Abstract
Cytotoxic T lymphocytes (CTLs) are important immune effectors against intra-cellular pathogens. These cells search for infected cells and kill them. Recently developed experimental methods in combination with mathematical models allow for the quantification of the efficacy of CTL killing in vivo and, hence, for the estimation of parameters that characterize the effect of CTL killing on the target cell populations. It is not known how these population-level parameters relate to single-cell properties. To address this question, we developed a three-dimensional cellular automaton model of the region of the spleen where CTL killing takes place. The cellular automaton model describes the movement of different cell populations and their interactions. Cell movement patterns in our cellular automaton model agree with observations from two-photon microscopy. We find that, despite the strong spatial nature of the kinetics in our cellular automaton model, the killing of target cells by CTLs can be described by a term which is linear in the target cell frequency and saturates with respect to the CTL levels. Further, we find that the parameters describing CTL killing on the population level are most strongly impacted by the time a CTL needs to kill a target cell. This suggests that the killing of target cells, rather than their localization, is the limiting step in CTL killing dynamics given reasonable frequencies of CTL. Our analysis identifies additional experimental directions which are of particular importance to interpret estimates of killing rates and could advance our quantitative understanding of CTL killing. The immune response mediated by cytotoxic T lymphocytes (CTLs), which kill infected cells, is thought to be essential to control viral infections. Experiments offer data which allow one to address the efficacy of this cell population in vivo and to estimate characterizing parameters. However, it is unclear which mathematical description reflects the experimental situation best and leads to reliable parameter estimates that quantify CTL efficacy. We simulate the spatial interaction of CTLs and infected cells in a 3-dimensional computer model to examine different mathematical descriptions of the experimental situation, independently of experimental data. Thereby we find an appropriate mathematical term to describe the killing process. Estimates obtained so far describe CTL efficacy on a population level. By varying the individual properties of simulated CTLs, such as the velocity, we find that the time a CTL needs to kill an infected cell is probably the key factor limiting CTL killing efficacy. Our analysis identifies additional experimental directions which could advance our quantitative understanding of CTL killing for different diseases.
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Affiliation(s)
- Frederik Graw
- Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland.
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12
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Kaur IP, Bhandari R, Bhandari S, Kakkar V. Potential of solid lipid nanoparticles in brain targeting. J Control Release 2008; 127:97-109. [DOI: 10.1016/j.jconrel.2007.12.018] [Citation(s) in RCA: 407] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2007] [Accepted: 12/17/2007] [Indexed: 01/04/2023]
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Abstract
In the new millennium, indications for splenectomy have expanded. Proper patient selection based on an understanding of the biology of each individual's disease is essential for a favorable outcome. We review the most common diseases for which surgeons may be called on to perform splenectomy and while highlighting potential pitfalls and caveats.
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Affiliation(s)
- Steven C. Katz
- From the Department of Surgery, New York University Medical Center and Bellevue Hospital Center, New York, NY
| | - H. Leon Pachter
- From the Department of Surgery, New York University Medical Center and Bellevue Hospital Center, New York, NY
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14
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Cullis ER, Kalber TL, Ashton SE, Cartwright JE, Griffiths JR, Ryan AJ, Robinson SP. Tumour overexpression of inducible nitric oxide synthase (iNOS) increases angiogenesis and may modulate the anti-tumour effects of the vascular disrupting agent ZD6126. Microvasc Res 2006; 71:76-84. [PMID: 16530791 DOI: 10.1016/j.mvr.2006.01.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 01/20/2006] [Accepted: 01/24/2006] [Indexed: 11/20/2022]
Abstract
Tumours derived from DLD-1 colon adenocarcinoma cells, transfected to either overexpress inducible nitric oxide synthase (clone iNOS-19) or with empty vector (pBAN2R), were utilised to test the hypothesis that tumour expression of iNOS (a) increases tumour angiogenesis and (b) modulates the anti-tumour activity of the vascular disrupting agent ZD6126. Overexpression of iNOS by clone iNOS-19 cells and murine xenografts was confirmed by the Griess assay and western blot analysis respectively. Clone iNOS-19 tumours grew more rapidly than pBAN2R tumours. Tumour perfusion, assessed by Hoechst 33342 uptake, was significantly greater in the clone iNOS-19 tumours (P < 0.001). A significant reduction in the perfusion of only the pBAN2R tumours, compared with control, was obtained 24 h after treatment with an intermediate dose of 100 mg/kg ZD6126 (P < 0.001), whereas 200 mg/kg significantly reduced the perfusion of both tumour types (P < 0.001). Whilst pBAN2R tumour necrosis increased in a dose-dependent manner, significant at 100 and 200 mg/kg ZD6126 (P < 0.05), intermediate doses did not induce a similar degree of necrosis in clone iNOS-19 tumours. A significant reduction in splenic perfusion was found 24 h after treatment with 100 mg/kg ZD6126, primarily associated with the red pulp. Overexpression of iNOS increases tumour growth, the degree of functionally perfused vasculature and angiogenesis, and also confers resistance to the vascular disrupting agent ZD6126.
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Affiliation(s)
- Elizabeth R Cullis
- Division of Basic Medical Sciences, St. George's, University of London, Cranmer Terrace, London SW17 ORE, UK
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15
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Eber S, Lux SE. Hereditary spherocytosis—defects in proteins that connect the membrane skeleton to the lipid bilayer. Semin Hematol 2004; 41:118-41. [PMID: 15071790 DOI: 10.1053/j.seminhematol.2004.01.002] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The molecular causes of hereditary spherocytosis (HS) have been unraveled in the past decade. No frequent defect is found, and nearly every family has a unique mutation. In dominant HS, nonsense and frameshift mutations of ankyrin, band 3, and beta-spectrin predominate. Recessive HS is most often due to compound heterozygosity of defects in ankyrin, alpha-spectrin, or protein 4.2. Common combinations include a defect in the promoter or 5'-untranslated region of ankyrin paired with a missense mutation, a low expression allele of alpha-spectrin plus a missense mutation, and various mutations in the gene for protein 4.2. In most patients' red cells, no abnormal protein is present. Only rare missense mutations, like ankyrin Walsrode (V463I) or beta-spectrin Kissimmee (W202R), have given any insight into the functional domains of the respective proteins. Although the eminent role of the spleen in the premature hemolysis of red cells in HS is unquestioned, the molecular events that cause splenic conditioning of spherocytes are unclear. Electron micrographs show that small membrane vesicles are shed during the formation of spherocytes. Animal models give further insight into the pathogenetic consequences of membrane protein defects as well as the causes of the variability of disease severity.
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Affiliation(s)
- Stefan Eber
- Division of Hematology/Oncology, Children's Hospital-Boston, Harvard Medical School, Boston, MA, USA.
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16
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Da Costa L, Mohandas N, Sorette M, Grange MJ, Tchernia G, Cynober T. Temporal differences in membrane loss lead to distinct reticulocyte features in hereditary spherocytosis and in immune hemolytic anemia. Blood 2001; 98:2894-9. [PMID: 11698268 DOI: 10.1182/blood.v98.10.2894] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Spherocytic red cells with reduced membrane surface area are a feature of hereditary spherocytosis (HS) and some forms of autoimmune hemolytic anemia (AIHA). It is generally assumed that membrane loss in spherocytic red cells occurs during their sojourn in circulation. The structural basis for membrane loss in HS is improper assembly of membrane proteins, whereas in AIHA it is due to partial phagocytosis of circulating red cells by macrophages. A hypothesis was formed that these different mechanisms should lead to temporal differences in surface area loss during red cell genesis and during sojourn in circulation in these 2 spherocytic syndromes. It was proposed that cell surface loss could begin at the reticulocyte stage in HS, whereas surface area loss in AIHA involves only circulating mature red cells. The validity of this hypothesis was established by documenting differences in cellular features of reticulocytes in HS and AIHA. Using a novel technique to quantitate cell surface area, the decreased membrane surface area of both reticulocytes and mature red cells in HS compared with normal cells was documented. In contrast, in AIHA only mature red cells but not reticulocytes exhibited decreased membrane surface area. These data imply that surface area loss in HS, but not in AIHA, is already present at the circulating reticulocyte stage. These findings imply that loss of cell surface area is an early event during genesis of HS red cells and challenge the existing concepts that surface area loss in HS occurs predominantly during the sojourn of mature red cells in circulation.
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Affiliation(s)
- L Da Costa
- Laboratoire d'hématologie, AP-HP, Faculté de Médecine Paris XI, INSERM U473, Hôpital de Bicêtre, Le Kremlin Bicêtre, France
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Moghimi SM, Hunter AC. Poloxamers and poloxamines in nanoparticle engineering and experimental medicine. Trends Biotechnol 2000; 18:412-20. [PMID: 10998507 DOI: 10.1016/s0167-7799(00)01485-2] [Citation(s) in RCA: 266] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Poloxamers and poloxamine nonionic surfactants have diverse applications in various biomedical fields ranging from drug delivery and medical imaging to management of vascular diseases and disorders. Although this is a progressive, rapidly advancing field in biotechnology, the future will depend on the recognition and rectification of a range of toxicity issues, which have to be addressed but have frequently been ignored until now.
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Affiliation(s)
- S M Moghimi
- The Molecular Targeting and Polymer Toxicology Group, School of Pharmacy and Biomolecular Sciences, Cockcroft Building, University of Brighton, BN2 4GJ., Brighton, UK.
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Rogausch H, del Rey A, Oertel J, Besedovsky HO. Norepinephrine stimulates lymphoid cell mobilization from the perfused rat spleen via beta-adrenergic receptors. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:R724-30. [PMID: 10070132 DOI: 10.1152/ajpregu.1999.276.3.r724] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The possibility that norepinephrine (NE) influences lymphoid cell outflow independently of its vasoconstrictor action was investigated in the perfused rat spleen. Using agents that affect the vasoconstrictor tonus of the spleen, we observed an inverse correlation between flow resistance and splenic cell output. The curve obtained served as a reference for evaluating effects of different treatments on the number of cells that are mobilized at defined levels of flow resistance. Perfusion of the beta-adrenergic blocker propranolol either alone or in combination with NE lowered splenic leukocyte outflow clearly beyond the number of cells expected at the corresponding flow resistance. No comparable effects were observed when the alpha-adrenergic blocker phentolamine was perfused. When the vasoconstrictor effect of NE was counteracted by papaverine, splenic cell outflow was significantly higher than expected for the level of flow resistance attained. Furthermore, when NE was perfused together with endotoxin, which does not inhibit the vasoconstriction induced by catecholamines, splenic cell mobilization was severalfold higher than expected at increased flow resistance. Propranolol abrogated this effect to a large extent. Furthermore, perfusion of the beta-agonist isoproterenol stimulated lymphoid cell outflow from the spleen despite increased flow resistance. These studies show a dual effect of NE on cell mobilization from the spleen: cell retention by decreasing blood flow and stimulation of cell output by a beta-adrenergically mediated, smooth muscle-independent mechanism.
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Affiliation(s)
- H Rogausch
- Division of Immunophysiology, Institute of Physiology, Medical Faculty, D-35037 Marburg, Germany
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Affiliation(s)
- W W Coon
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, USA
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20
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Moghimi S. Mechanisms of splenic clearance of blood cells and particles: towards development of new splenotropic agents. Adv Drug Deliv Rev 1995. [DOI: 10.1016/0169-409x(95)00043-7] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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21
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Goerdt S, Walsh LJ, Murphy GF, Pober JS. Identification of a novel high molecular weight protein preferentially expressed by sinusoidal endothelial cells in normal human tissues. J Cell Biol 1991; 113:1425-37. [PMID: 2045420 PMCID: PMC2289031 DOI: 10.1083/jcb.113.6.1425] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Mouse mAb MS-1, raised against human spleen, detects an endothelial cell antigen abundantly expressed by the sinusoidal endothelia of spleen, lymph node, liver, and adrenal cortex, but absent from nonsinusoidal continuous endothelia in these organs. Immunoelectron microscopy of splenic tissue demonstrates that the MS-1 antigen is predominantly deposited at zones of intercellular contact between adjacent sinusoidal endothelial cells. mAb MS-1 also reacts with a variable proportion of high endothelial venules in tonsil, but not in other lymphoid tissues, and with an interstitial dendritic cell population most abundant in placenta. mAb MS-1 does not react with cultured resting or mediator- activated human umbilical vein endothelial cells, dermal fibroblasts, peripheral blood mononuclear cells, or the cell lines U937, HL-60, K562 or Mo7E; it does react with the primitive myeloid cell line KG-1. mAb MS-1 immunoprecipitates a major protein of 215 kD and minor proteins of 320 and 120 kD from splenic extracts as analyzed by SDS-PAGE with reduction. These proteins are soluble in aqueous buffers. Immunoprecipitation from KG-1 cell lysates detects four proteins of 280, 300, 205, and 120 kD; the 300-, 205-, and 120-kD species, presumably corresponding to the 320-, 215-, and 120-kD species in spleen, respectively, are secreted into the media. Under nonreducing conditions, immunoprecipitates from KG-1 cell lysates or conditioned media contain one predominant 300-kD species; upon isolation and reduction, this 300-kD species separates into the previously observed 300-, 205-, and 120-kD species. Pulse-chase experiments and limited proteolysis peptide mapping suggest that the 280-kD species is a precursor of the mature 300-kD species which may be subsequently cleaved to yield the 205- and 120-kD species. Because of its size, solubility and expression pattern, the antigen recognized by mAb MS-1 is likely to be an extracellular matrix protein utilized by endothelial cells of contorted, large caliber, or leaky microvessels that lack a well-formed basement membrane.
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Affiliation(s)
- S Goerdt
- Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115
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Abstract
Barrier cells are a newly defined group of activated fibroblastic cells that are deployed as diverse barriers in the splenic pulp. The central capacity of the spleen, namely clearance of the blood, is normally modest but when stressed, for example by infectious disease, imperfect blood cells or the administration of interleukin 1, the clearance capacities of the spleen expand. The normally scarce barrier cells rapidly and greatly increase in number in splenic stress. By augmenting the splenic filtration beds, regulating blood flow, enveloping white pulp and enclosing hematopoietic colonies, they appear to be important in the spleen's increased capacities in clearance, phagocytosis, immunological reactivity and hematopoiesis. This review focuses on their role in the spleen, but barrier cells may appear throughout the body in response to needs for walling off and cellular induction.
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Affiliation(s)
- L Weiss
- Laboratory of Experimental Hematology and Cell Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104-6046
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Abstract
I believe that my laboratory has developed a construct of the spleen useful in understanding its range of normal and pathologic functions. The elements in the construct include recognition of an anatomically open vasculature with the interposition of reticular cell-reticular fiber filtration beds between terminal arterial vessels and proximal venules. The central function of the spleen, moreover--selective clearance of cells, microbes and other particles from the blood--depends upon these filtration beds. Such functions of the spleen as phagocytosis, immunologic reactivity, hematopoiesis, and blood cell storage derive from its clearance capacities. The reticular filtration beds offer but modest levels of basal clearance. The wide ranges of filtration that characterize the stressed spleen depend upon arming or augmenting the basic reticular filtration beds with responsive cells which can rapidly appear, and rapidly disappear. These include macrophages, salient phagocytic cells of rich repertoire, which have been accorded the major, even exclusive, role in splenic clearance. But other stromal cells participate in splenic clearance. I have identified a system of fibroblastic, contractile, granulated cells which fuse to form complex, branched syncytial sheets which, deployed as diverse barriers, augment the basic reticular filtration beds. Hence, I term these cells barrier cells. Barrier cells effectively interact with macrophages, reticular cells, other stromal and blood cells, contributing to the extraordinary range of splenic clearance capacities. Barrier cells may be elicited by a variety of infectious processes, damaged blood cells and hematopoietic factors. Interleukin-1-alpha evokes a strong barrier cell response, and may be the common denominator in splenic stress, stimulated by activated macrophages.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- L Weiss
- Laboratory of Experimental Hematology and Cell Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104-6046
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