Dataset Information

Distinct Features of Germinal Center Reactions in Macaques Infected by SIV or Vaccinated with a T-Dependent Model Antigen.

ABSTRACT: B-cell follicles constitute large reservoirs of infectious HIV/SIV associated to follicular dendritic cells and infecting follicular helper (T_FH) and regulatory (T_FR) T-cells in germinal centers (GCs). Thus, follicular and GC B-cells are persistently exposed to viral antigens. Despite recent development of potent HIV immunogens, numerous questions are still open regarding GC reaction during early HIV/SIV infection. Here, we dissect the dynamics of B- and T-cells in GCs of macaques acutely infected by SIV (Group SIV⁺) or vaccinated with Tetanus Toxoid (Group TT), a T-dependent model antigen. Systemic inflammation and mobilization of antigen-presenting cells in inguinal lymph nodes and spleen are lower in Group TT than in Group SIV⁺. Despite spleen GC reaction of higher magnitude in Group SIV^+, the development of protective immunity could be limited by abnormal helper functions of T_FH massively polarized into T_FH1-like cells, by inflammation-induced recruitment of fCD8 (either regulatory or cytotoxic) and by low numbers of T_FR limiting T_FH/T_FR competition for high affinity B-cells. Increased GC B-cells apoptosis and accumulation of CD21^lo memory B-cells, unable to further participate to GC reaction, likely contribute to eliminate SIV-specific B-cells and decrease antibody affinity maturation. Surprisingly, functional GCs and potent TT-specific antibodies develop despite low levels of CXCL13.

SUBMITTER: Trovato M

PROVIDER: S-EPMC7916050 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Distinct Features of Germinal Center Reactions in Macaques Infected by SIV or Vaccinated with a T-Dependent Model Antigen.

Trovato Maria M Ibrahim Hany M HM Isnard Stephane S Le Grand Roger R Bosquet Nathalie N Borhis Gwenoline G Richard Yolande Y

Viruses 20210209 2

B-cell follicles constitute large reservoirs of infectious HIV/SIV associated to follicular dendritic cells and infecting follicular helper (T<sub>FH</sub>) and regulatory (T<sub>FR</sub>) T-cells in germinal centers (GCs). Thus, follicular and GC B-cells are persistently exposed to viral antigens. Despite recent development of potent HIV immunogens, numerous questions are still open regarding GC reaction during early HIV/SIV infection. Here, we dissect the dynamics of B- and T-cells in GCs of m ...[more]

PMID: 33572146

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Dataset Information

Distinct Features of Germinal Center Reactions in Macaques Infected by SIV or Vaccinated with a T-Dependent Model Antigen.

Publications

Distinct Features of Germinal Center Reactions in Macaques Infected by SIV or Vaccinated with a T-Dependent Model Antigen.

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