The Three-dimensional Structure of Human Splenic White Pulp Compartments

The precise arrangement of B- and T-lymphocytes in the different compartments of the human splenic white pulp is still largely unknown. We therefore performed a 3D reconstruction of 150 serial sections of a representative adult human spleen alternately stained for CD3 and CD20. The results indicate that the T-cell regions of human spleens may be interrupted by B-cell follicles. Therefore, there is no continuous periarteriolar lymphatic T-cell sheath (PALS) around white pulp arterioles. An arteriole may be surrounded by T-lymphocytes at one level, then run across a follicle without any T-cells around, and finally re-enter a T-cell region. T- and B-cell compartments are intricately interdigitated in the human splenic white pulp. CD4+ T-lymphocytes and the typical fibroblasts of the T-cell region may extend as a thin shell at the follicular surface within the marginal zone. On the other hand, IgD++ B-cells continue from the follicular outer marginal zone along the surface of the T-cell region. Our findings indicate that the microanatomy of the splenic white pulp differs between humans and rodents. This may have consequences for the immigration of recirculating lymphocytes and for initial interactions among antigen-specific T- and B-lymphocytes.

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Fc chimeric protein containing the cysteine-rich domain of the murine mannose receptor binds to macrophages from splenic marginal zone and lymph node subcapsular sinus and to germinal centers.

Journal of Experimental Medicine ◽

10.1084/jem.184.5.1927 ◽

1996 ◽

Vol 184 (5) ◽

pp. 1927-1937 ◽

Cited By ~ 125

Author(s):

L Martínez-Pomares ◽

M Kosco-Vilbois ◽

E Darley ◽

P Tree ◽

S Herren ◽

...

Keyword(s):

Lymph Node ◽

Lymph Nodes ◽

B Cell ◽

Marginal Zone ◽

Chimeric Protein ◽

Mannose Receptor ◽

Germinal Centers ◽

White Pulp ◽

Subcapsular Sinus ◽

Splenic White Pulp

Ligands for the cysteine-rich (CR) domain of the mannose receptor (MR) were detected by incubating murine tissues with a chimeric protein containing CR fused to the Fc region of human IgG1 (CR-Fc). In naive mice, CR-Fc bound to sialoadhesin+, F4/80low/-, macrosialin+ macrophages (M phi) in spleen marginal zone (metallophilic M phi) and lymph node subcapsular sinus. Labeling was also observed in B cell areas of splenic white pulp. Western blotting analysis of spleen and lymph nodes lysates revealed a restricted number of molecules that interacted specifically with CR-Fc. In immunized mice, labeling was upregulated on germinal centers in splenic white pulp and follicular areas of lymph nodes. Kinetic analysis of the pattern of CR-Fc labeling in lymph nodes during a secondary immune response to ovalbumin showed that CR ligand expression migrated towards B cell areas, associated with cells displaying distinctive dendritic morphology, and accumulated in developing germinal centers. These studies suggest that MR+ cells or MR-carbohydrate-containing antigen complexes could be directed towards areas where humoral immune responses take place, through the interaction of the MR CR domain with molecules expressed in specialized macrophage populations and antigen transporting cells.

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In silico Design of novel Multi-epitope recombinant Vaccine based on Coronavirus surface glycoprotein

10.1101/2020.03.10.985499 ◽

2020 ◽

Cited By ~ 4

Author(s):

Mandana Behbahani

Keyword(s):

T Cell ◽

Immune Responses ◽

B Cell ◽

Ribosomal Protein ◽

In Silico ◽

Three Dimensional ◽

Surface Glycoprotein ◽

Dimensional Structure ◽

Effective Vaccine ◽

Epitope Vaccine

AbstractIt is of special significance to find a safe and effective vaccine against coronavirus disease 2019 (COVID-19) that can induce T cell and B cell -mediated immune responses. There is currently no vaccine to prevent COVID-19. In this project, a novel multi-epitope vaccine for COVID-19 virus based on surface glycoprotein was designed through application of bioinformatics methods. At the first, seventeen potent linear B-cell and T-cell binding epitopes from surface glycoprotein were predicted in silico, then the epitopes were joined together via different linkers. The ability of the selected epitopes to induce interferon-gamma was evaluate using IFNepitope web server. One final vaccine was constructed which composed of 398 amino acids and attached to 50S ribosomal protein L7/L12 as adjuvant. Physicochemical properties, as well as antigenicity in the proposed vaccines, were checked for defining the vaccine stability and its ability to induce cell-mediated immune responses. Three-dimensional structure of the mentioned vaccine was subjected to the molecular docking studies with MHC-I and MHC-II molecules. The results proposed that the multi-epitope vaccine with 50S ribosomal protein L7/L12 was a stable construct with high aliphatic content and high antigenicity.

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Investigation of human spleen dendritic cell phenotype and distribution reveals evidence of in vivo activation in a subset of organ donors

Blood ◽

10.1182/blood.v97.11.3470 ◽

2001 ◽

Vol 97 (11) ◽

pp. 3470-3477 ◽

Cited By ~ 59

Author(s):

Dorian McIlroy ◽

Christelle Troadec ◽

Fernanda Grassi ◽

Assia Samri ◽

Benoı̂t Barrou ◽

...

Keyword(s):

T Cell ◽

Dendritic Cell ◽

Marginal Zone ◽

Rare Event ◽

Mouse Spleen ◽

Cell Phenotype ◽

White Pulp ◽

Organ Donors ◽

Human Spleen

Although the mouse spleen dendritic cell (DC) is perhaps the most intensively studied DC type, little has been published concerning its human equivalent. In this report, rare event flow cytometry and in situ immunofluorescence were used to study the surface phenotype and distribution of HLA-DR+CD3−14−16−19− human spleen DC. Spleens from organ donors with different clinical histories were used. Most (81% ± 9%; n = 14) spleen DCs expressed high levels of the integrin CD11c. CD11c+ DCs were distributed in 3 distinct regions—the peri-arteriolar T-cell zones, the B-cell zones, and the marginal zone, where they formed a ring of cells surrounding the white pulp, just inside a ring of CD14+ red pulp macrophages, apparently more regularly organized than the previously described marginating DC population in the mouse spleen. The T-cell zones contained CD86+ DCs, among which a subpopulation expressed CD83. These mature/activated CD86+DCs represented a minority (12% ± 8%) of total spleen DCs in most organ donors: most spleen DCs are immature. In 3 of 18 (17%) donors, however, most (54%-81%) of spleen DCs were CD86+, suggesting that in vivo DC activation had occurred. In one donor, a radical shift in DC distribution from the marginal zone to the T-cell zones was also observed. This activation of spleen DCs in vivo was reminiscent of the effects of experimental microbial product injection in mice, and it seemed to correlate with bacterial infection or multiple trauma.

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An immunoinformatics approach for the design of a multi-epitope vaccine targeting super antigen TSST-1 of Staphylococcus aureus

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-021-00160-z ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Harish Babu Kolla ◽

Chakradhar Tirumalasetty ◽

Krupanidhi Sreerama ◽

Vijaya Sai Ayyagari

Keyword(s):

Staphylococcus Aureus ◽

T Cell ◽

B Cell ◽

In Silico ◽

Three Dimensional ◽

Clinical Manifestations ◽

Food Poisoning ◽

Dimensional Structure ◽

T Cell Epitopes ◽

Epitope Vaccine

Abstract Background TSST-1 is a secretory and pyrogenic superantigen that is being responsible for staphylococcal mediated food poisoning and associated clinical manifestations. It is one of the main targets for the construction of vaccine candidates against Staphylococcus aureus. Most of the vaccines have met failure due to adverse reactions and toxicity reported during late clinical studies. To overcome this, an immunoinformatics approach is being used in the present study for the design of a multi-epitope vaccine to circumvent the problems related to toxicity and allergenicity. Results In this study, a multi-epitope vaccine against Staphylococcus aureus targeting TSST-1 was designed through an immunoinformatics approach. B cell and T cell epitopes were predicted in silico and mapped with linkers to avoid junctional immunogenicity and to ensure the efficient presentation of exposed epitopes through HLA. β-defensin and PADRE were adjusted at the N-terminal end of the final vaccine as adjuvants. Physiochemical parameters, antigenicity, and allergenicity of the vaccine construct were determined with the help of online servers. The three-dimensional structure of the vaccine protein was predicted and validated with various tools. The affinity of the vaccine with TLR-3 was studied through molecular docking studies and the interactions of two proteins were visualized using LigPlot+. The vaccine was successfully cloned in silico into pET-28a (+) for efficient expression in E. coli K12 system. Population coverage analysis had shown that the vaccine construct can cover 83.15% of the global population. Immune simulation studies showed an increase in the antibody levels, IL-2, IFN-γ, TGF-β, B cell, and T cell populations and induced primary, secondary, and tertiary immune responses. Conclusion Multi-epitope vaccine designed through a computational approach is a non-allergic and non-toxic antigen. Preliminary in silico reports have shown that this vaccine could elicit both B cell and T cell responses in the host as desired.

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Epiligrin, a component of epithelial basement membranes, is an adhesive ligand for alpha 3 beta 1 positive T lymphocytes.

The Journal of Cell Biology ◽

10.1083/jcb.121.5.1141 ◽

1993 ◽

Vol 121 (5) ◽

pp. 1141-1152 ◽

Cited By ~ 126

Author(s):

E A Wayner ◽

S G Gil ◽

G F Murphy ◽

M S Wilke ◽

W G Carter

Keyword(s):

T Cells ◽

T Cell ◽

T Lymphocytes ◽

Basement Membrane ◽

B Cell ◽

Cell Lines ◽

B Cell Lymphoma ◽

Lymphokine Activated Killer Cells ◽

Cutaneous Inflammation ◽

Epidermal Basement Membrane

The cutaneous T cell lymphomas (CTCL), typified by mycosis fungoides, and several chronic T cell mediated dermatoses are characterized by the migration of T lymphocytes into the epidermis (epidermotropism). Alternatively, other types of cutaneous inflammation (malignant cutaneous B cell lymphoma, CBCL, or lymphocytoma cutis, non-malignant T or B cell type) do not show evidence of epidermotropism. This suggests that certain T lymphocyte subpopulations are able to interact with and penetrate the epidermal basement membrane. We show here that T lymphocytes derived from patients with CTCL (HUT 78 or HUT 102 cells), adhere to the detergent-insoluble extracellular matrix prepared from cultured basal keratinocytes (HFK ECM). HUT cell adhesion to HFK ECM was inhibitable with monoclonal antibodies (mAbs) directed to the alpha 3 (P1B5) or beta 1 (P4C10) integrin receptors, and could be up-regulated by an activating anti-beta 1 mAb (P4G11). An inhibitory mAb, P3H9-2, raised against keratinocytes identified epiligrin as the ligand for alpha 3 beta 1 positive T cells in HFK ECM. Interestingly, two lymphocyte populations could be clearly distinguished relative to expression of alpha 3 beta 1 by flow cytometry analysis. Lymphokine activated killer cells, alloreactive cytotoxic T cells and T cells derived from patients with CTCL expressed high levels of alpha 3 beta 1 (alpha 3 beta 1high). Non-adherent peripheral blood mononuclear cells, acute T or B lymphocytic leukemias, or non-cutaneous T or B lymphocyte cell lines expressed low levels of alpha 3 beta 1 (alpha 3 beta 1low). Resting PBL or alpha 3 beta 1low T or B cell lines did not adhere to HFK ECM or purified epiligrin. However, adhesion to epiligrin could be up-regulated by mAbs which activate the beta 1 subunit indicating that alpha 3 beta 1 activity is a function of expression and affinity. In skin derived from patients with graft-vs.-host (GVH) disease, experimentally induced delayed hypersensitivity reactions, and CTCL, the infiltrating T cells could be stained with mAbs to alpha 3 or beta 1 and were localized in close proximity to the epiligrin-containing basement membrane. Infiltrating lymphocytes in malignant cutaneous B disease (CBCL) did not express alpha 3 beta 1 by immunohistochemical techniques and did not associate with the epidermal basement membrane. The present findings clearly define a function for alpha 3 beta 1 in T cells and strongly suggest that alpha 3 beta 1 interaction with epiligrin may be involved in the pathogenesis of cutaneous inflammation.

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Morphometric and Histopathologic Analysis of Lymphoid Depletion in Murine Spleens Following Infection with Brucella abortus strains 2308 or RB51 or an htrA Deletion Mutant

Veterinary Pathology ◽

10.1177/030098589603300304 ◽

1996 ◽

Vol 33 (3) ◽

pp. 282-289 ◽

Cited By ~ 9

Author(s):

M. V. Palmer ◽

N. F. Cheville ◽

F. M. Tatum

Keyword(s):

Morphometric Analysis ◽

Brucella Abortus ◽

Marginal Zone ◽

White Pulp ◽

Splenic White Pulp ◽

Lymphoid Depletion ◽

Histopathologic Changes ◽

Histopathologic Analysis ◽

Marginal Zones

BALB/C mice were inoculated intraperitoneally with suspensions of Brucella abortus strains 2308 or RB51 or an htrA mutant. Spleens were examined on postinoculation day (PID) 2, 4, 7, 10, 15, 21, 30, and 60. Brucellae were cultured in high numbers from the spleens of mice infected with strains 2308 or htrA through PID 60; however, mice infected with strain RB51 cleared the infection between PID 30 and PID 60. Histopathologic changes in spleens from 2308-infected mice were characterized by marked accumulations of macrophages, which expanded marginal zones beginning as early as PID 7 and persisting through PID 60. Morphometric analysis showed a decrease in splenic white pulp in 2308-infected mice at PID 10, which correlated with the peak of bacterial infection. Although this decrease was significant ( P < 0.05) when compared with values at the previous (PID 7) and the following (PID 15) time periods, it was not significantly different from white pulp values noted at PID 2 or PID 4 or the values for control spleens. Spleens from RB51-infected mice showed only mild to moderate accumulations of macrophages in marginal zone areas during the peak of RB51 infection (PID 7-10). Morphometric analysis of RB51-infected spleens showed a decrease in white pulp area, which coincided with peak bacterial numbers. However, this decrease was not significant ( P > 0.05). Spleens from mice infected with the htrA mutant showed moderate to marked accumulations of macrophages in marginal zone areas, which persisted through PID 60. Multifocal necrosis in lymphoid follicles as early as PID 4 was seen in both htrA and 2308 infection. Morphometric analysis of htrA-infected spleens revealed no significant decrease in white pulp and no obvious correlation with bacterial numbers in the spleen. These results suggest that virulent B. abortus does not induce lymphoid depletion significantly below those values seen in noninfected mice; thus, the possible role of lymphoid depletion in the pathogenesis of brucellosis remains questionable.

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Immunoinformatic Study of Recombinant LigA/BCon1-5 Antigen and Evaluation of Its Diagnostic Potential in Primary and Secondary Binding Tests for Serodiagnosis of Porcine Leptospirosis

Pathogens ◽

10.3390/pathogens10091082 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1082

Author(s):

Sujit Kumar Behera ◽

Thankappan Sabarinath ◽

Prasanta Kumar K. Mishra ◽

Yosef Deneke ◽

Ashok Kumar ◽

...

Keyword(s):

B Cell ◽

Animal Health ◽

Three Dimensional ◽

Agglutination Test ◽

Dimensional Structure ◽

Dipstick Test ◽

Mhc I ◽

Three Dimensional Structure ◽

Bioinformatics Tools ◽

Dot Elisa

Leptospirosis is responsible for hampering the productivity of swine husbandry worldwide. The aim of this study was to assess the efficacy of bioinformatics tools in predicting the three-dimensional structure and immunogenicity of recombinant LigBCon1-5 (rLigBCon1-5) antigen. A battery of bioinformatics tools such as I-TASSER, ProSA and SAVES v6.0 were used for the prediction and assessment of the predicted structure of rLigBCon1-5 antigen. Bepipred-2.0, DiscoTope v2.0 and ElliPro servers were used to predict linear and conformational epitopes while T-cell epitopes were predicted using NetMHCpan 4.1 and IEDB recommended 2.22 method for MHC Class I and II peptides respectively. The results obtained using various in silico methods were then compared with wet lab experiments comprising of both primary (IgG Dot ELISA Dipstick test) and secondary-binding assays (Latex Agglutination Test [LAT]) to screen 1153 porcine serum samples. The three-dimensional structure of rLigA/BCon1-5 protein as predicted by I-TASSER was found to be reliable by Ramachandran Plot and ProSA. The ElliPro server suggested 10 and three potential linear and conformational B-cell-epitopes, respectively, on the peptide backbone of the rLigA/BCon1-5 protein. The DiscoTope prediction server suggested 47 amino acid residues to be part of B-cell antigen. Ten of the most efficient peptides for MHC-I and II grooves were predicted by NetMHCpan 4.1 and IEDB recommended 2.22 method, respectively. Of these, three peptides can serve dual functions as it can fit both MHC I and II grooves, thereby eliciting both humoral-and cell-mediated immune responses. The prediction of these computational approaches proved to be reliable since rLigBCon1-5 antigen-based IgG Dot ELISA Dipstick test and LAT gave results in concordance to gold standard test, the Microscopic Agglutination Test (MAT), for serodiagnosis of leptospirosis. Both the IgG Dot ELISA Dipstick test and LAT were serodiagnostic assays ideally suited for peripheral level of animal health care system as “point of care” tests for the detection of porcine leptospirosis.

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Marginal Zone B Cells Mediate a CD4 T Cell Dependent Extrafollicular Antibody Response Following RBC Transfusion in Mice

Blood ◽

10.1182/blood.2020009376 ◽

2021 ◽

Author(s):

Patricia E Zerra ◽

Seema R Patel ◽

Ryan Philip Jajosky ◽

Connie M Arthur ◽

James W McCoy ◽

...

Keyword(s):

T Cell ◽

B Cells ◽

Antibody Response ◽

B Cell ◽

T Cell Activation ◽

Antibody Formation ◽

Marginal Zone ◽

Cd4 T Cell ◽

Marginal Zone B Cells ◽

Rbc Transfusion

Red blood cell (RBC) transfusions can result in alloimmunization toward RBC alloantigens that can increase the probability of complications following subsequent transfusion. An improved understanding of the immune mechanisms that underlie RBC alloimmunization is critical if future strategies capable of preventing or even reducing this process are to be realized. Using the HOD (hen egg lysozyme and ovalbumin fused to human Duffy) model system, we aimed to identify initiating immune factors that may govern early anti-HOD alloantibody formation. Our findings demonstrate that HOD RBCs continuously localize to the marginal sinus following transfusion, where they co-localize with marginal zone (MZ) B cells. Depletion of MZ B cells inhibited IgM and IgG anti-HOD antibody formation, while CD4 T cell depletion only prevented IgG anti-HOD antibody development. HOD-specific CD4 T cells displayed similar proliferation and activation following transfusion of HOD RBCs into wild type or MZ B cell deficient recipients, suggesting that IgG formation is not dependent on MZ B cell-mediated CD4 T cell activation. Moreover, depletion of follicular B cells failed to substantially impact the anti-HOD antibody response and no increase in antigen specific germinal center B cells was detected following HOD RBC transfusion, suggesting that antibody formation is not dependent on the splenic follicle. Despite this, anti-HOD antibodies persisted for several months following HOD RBC transfusion. Overall, these data suggest MZ B cells can initiate and then contribute to RBC alloantibody formation, highlighting a unique immune pathway that can be engaged following RBC transfusion.

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