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Transient CD4+ T Cell Depletion Results in Delayed Development of Functional Vaccine-Elicited Antibody Responses.

Provine NM, Badamchi-Zadeh A, Bricault CA, Penaloza-MacMaster P, Larocca RA, Borducchi EN, Seaman MS, Barouch DH - J. Virol. (2016)

Bottom Line: Upon CD4(+)T cell recovery, transgene-specific serum IgG antibody titers develop and reach a concentration equivalent to that in undepleted control animals.The paradigm is that helper signals must be provided immediately upon antigen exposure, and their absence results in tolerance against the antigen.These data demonstrate that the time when CD4(+)T cell help signals must be provided is more dynamic and flexible than previously appreciated.

View Article: PubMed Central - PubMed

Affiliation: Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.

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Delayed development of antibody responses following depletion of CD4+ T cells. (A) C57BL/6 mice were depleted of CD4+ T cells at the indicated days or left untreated and immunized intramuscularly with 1010 vp of Ad26-SIV Env. (B) SIV Env-specific serum-binding antibody titers at the indicated days postimmunization. Gray, no anti-CD4 treatment; red, anti-CD4 given on the indicated day; white, naive animals. (C and D) Representative flow cytometry plots (C) and absolute numbers (D) of germinal center (GC) B cell responses in the iliac LNs on day 14 postimmunization, with gating on CD3ε− CD19+ cells. (E) Spearman correlation analysis of the number of germinal center B cells in iliac LNs and serum SIV Env-specific binding antibody titers on day 14 postimmunization in mice treated with anti-CD4 at the days indicated. (F) SIV Env-specific serum-binding antibody titers in wild-type (WT), CD40L KO, or CD40 KO mice immunized with 109 vp of Ad26-SIV Env. Each dot represents an individual mouse, and the line is the median (B and F) or the mean ± the standard error of the mean (D). The horizontal dotted line denotes the limit of detection of the assay (for panel B, n = 4/group from one experiment [day 14] or n = 8/group pooled from two experiments [days 30, 60, and 90]; for panel D, n = 4/group from one experiment; for panel F, n = 8/group pooled from two experiments).
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Figure 1: Delayed development of antibody responses following depletion of CD4+ T cells. (A) C57BL/6 mice were depleted of CD4+ T cells at the indicated days or left untreated and immunized intramuscularly with 1010 vp of Ad26-SIV Env. (B) SIV Env-specific serum-binding antibody titers at the indicated days postimmunization. Gray, no anti-CD4 treatment; red, anti-CD4 given on the indicated day; white, naive animals. (C and D) Representative flow cytometry plots (C) and absolute numbers (D) of germinal center (GC) B cell responses in the iliac LNs on day 14 postimmunization, with gating on CD3ε− CD19+ cells. (E) Spearman correlation analysis of the number of germinal center B cells in iliac LNs and serum SIV Env-specific binding antibody titers on day 14 postimmunization in mice treated with anti-CD4 at the days indicated. (F) SIV Env-specific serum-binding antibody titers in wild-type (WT), CD40L KO, or CD40 KO mice immunized with 109 vp of Ad26-SIV Env. Each dot represents an individual mouse, and the line is the median (B and F) or the mean ± the standard error of the mean (D). The horizontal dotted line denotes the limit of detection of the assay (for panel B, n = 4/group from one experiment [day 14] or n = 8/group pooled from two experiments [days 30, 60, and 90]; for panel D, n = 4/group from one experiment; for panel F, n = 8/group pooled from two experiments).

Mentions: We first sought to determine the time at which CD4+ T cell help is required for the induction of transgene antigen-specific antibody responses by Ad vector vaccination. To accomplish this, C57BL/6 mice were immunized i.m. with 1010 vp of Ad26-SIV Env and depleted of CD4+ T cells by the administration of anti-CD4 antibody GK1.5 on either day −1, day 3, day 7, day 10, day 14, day 21, or day 28 postimmunization or left untreated, as a control (Fig. 1A). In untreated control mice, robust SIV Env-specific serum antibody titers were detected on day 14 postimmunization and were maintained for at least 90 days (Fig. 1B). Depletion of CD4+ T cells prior to immunization or on day 3 postimmunization resulted in nearly undetectable Env-specific antibody responses at days 14 and 30 postimmunization (Fig. 1B). Depletion of CD4+ T cells on day 7 or 10 postimmunization had progressively less of an impact on Env-specific antibody titers measured on day 30, and depletion of CD4+ T cells on or after day 14 postimmunization had no impact on antibody titers measured on day 30 (Fig. 1B). As expected, the decrease in antibody titers observed following the depletion of CD4+ T cells was highly correlated with reductions in the frequencies of germinal center B cells in the iliac (draining) lymph nodes (LNs) on day 14 postimmunization (r = 0.76 by Spearman test; P = 0.001) (Fig. 1C to E). Signaling by CD4+ T cells through CD40 is a well-described mechanism by which CD4+ T cells promote antibody responses (13). We confirmed that CD40 was an important signaling pathway for antigen-specific antibody responses following Ad vector immunization, as the absence of CD40L or CD40 resulted in a complete abolishment of Env-specific antibody responses on day 30 postimmunization (Fig. 1F). Thus, following Ad vector immunization, induction of antigen-specific antibody responses requires CD4+ T cell help to promote germinal center responses via CD40-derived signals, consistent with data obtained by using other experimental systems (34).


Transient CD4+ T Cell Depletion Results in Delayed Development of Functional Vaccine-Elicited Antibody Responses.

Provine NM, Badamchi-Zadeh A, Bricault CA, Penaloza-MacMaster P, Larocca RA, Borducchi EN, Seaman MS, Barouch DH - J. Virol. (2016)

Delayed development of antibody responses following depletion of CD4+ T cells. (A) C57BL/6 mice were depleted of CD4+ T cells at the indicated days or left untreated and immunized intramuscularly with 1010 vp of Ad26-SIV Env. (B) SIV Env-specific serum-binding antibody titers at the indicated days postimmunization. Gray, no anti-CD4 treatment; red, anti-CD4 given on the indicated day; white, naive animals. (C and D) Representative flow cytometry plots (C) and absolute numbers (D) of germinal center (GC) B cell responses in the iliac LNs on day 14 postimmunization, with gating on CD3ε− CD19+ cells. (E) Spearman correlation analysis of the number of germinal center B cells in iliac LNs and serum SIV Env-specific binding antibody titers on day 14 postimmunization in mice treated with anti-CD4 at the days indicated. (F) SIV Env-specific serum-binding antibody titers in wild-type (WT), CD40L KO, or CD40 KO mice immunized with 109 vp of Ad26-SIV Env. Each dot represents an individual mouse, and the line is the median (B and F) or the mean ± the standard error of the mean (D). The horizontal dotted line denotes the limit of detection of the assay (for panel B, n = 4/group from one experiment [day 14] or n = 8/group pooled from two experiments [days 30, 60, and 90]; for panel D, n = 4/group from one experiment; for panel F, n = 8/group pooled from two experiments).
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Figure 1: Delayed development of antibody responses following depletion of CD4+ T cells. (A) C57BL/6 mice were depleted of CD4+ T cells at the indicated days or left untreated and immunized intramuscularly with 1010 vp of Ad26-SIV Env. (B) SIV Env-specific serum-binding antibody titers at the indicated days postimmunization. Gray, no anti-CD4 treatment; red, anti-CD4 given on the indicated day; white, naive animals. (C and D) Representative flow cytometry plots (C) and absolute numbers (D) of germinal center (GC) B cell responses in the iliac LNs on day 14 postimmunization, with gating on CD3ε− CD19+ cells. (E) Spearman correlation analysis of the number of germinal center B cells in iliac LNs and serum SIV Env-specific binding antibody titers on day 14 postimmunization in mice treated with anti-CD4 at the days indicated. (F) SIV Env-specific serum-binding antibody titers in wild-type (WT), CD40L KO, or CD40 KO mice immunized with 109 vp of Ad26-SIV Env. Each dot represents an individual mouse, and the line is the median (B and F) or the mean ± the standard error of the mean (D). The horizontal dotted line denotes the limit of detection of the assay (for panel B, n = 4/group from one experiment [day 14] or n = 8/group pooled from two experiments [days 30, 60, and 90]; for panel D, n = 4/group from one experiment; for panel F, n = 8/group pooled from two experiments).
Mentions: We first sought to determine the time at which CD4+ T cell help is required for the induction of transgene antigen-specific antibody responses by Ad vector vaccination. To accomplish this, C57BL/6 mice were immunized i.m. with 1010 vp of Ad26-SIV Env and depleted of CD4+ T cells by the administration of anti-CD4 antibody GK1.5 on either day −1, day 3, day 7, day 10, day 14, day 21, or day 28 postimmunization or left untreated, as a control (Fig. 1A). In untreated control mice, robust SIV Env-specific serum antibody titers were detected on day 14 postimmunization and were maintained for at least 90 days (Fig. 1B). Depletion of CD4+ T cells prior to immunization or on day 3 postimmunization resulted in nearly undetectable Env-specific antibody responses at days 14 and 30 postimmunization (Fig. 1B). Depletion of CD4+ T cells on day 7 or 10 postimmunization had progressively less of an impact on Env-specific antibody titers measured on day 30, and depletion of CD4+ T cells on or after day 14 postimmunization had no impact on antibody titers measured on day 30 (Fig. 1B). As expected, the decrease in antibody titers observed following the depletion of CD4+ T cells was highly correlated with reductions in the frequencies of germinal center B cells in the iliac (draining) lymph nodes (LNs) on day 14 postimmunization (r = 0.76 by Spearman test; P = 0.001) (Fig. 1C to E). Signaling by CD4+ T cells through CD40 is a well-described mechanism by which CD4+ T cells promote antibody responses (13). We confirmed that CD40 was an important signaling pathway for antigen-specific antibody responses following Ad vector immunization, as the absence of CD40L or CD40 resulted in a complete abolishment of Env-specific antibody responses on day 30 postimmunization (Fig. 1F). Thus, following Ad vector immunization, induction of antigen-specific antibody responses requires CD4+ T cell help to promote germinal center responses via CD40-derived signals, consistent with data obtained by using other experimental systems (34).

Bottom Line: Upon CD4(+)T cell recovery, transgene-specific serum IgG antibody titers develop and reach a concentration equivalent to that in undepleted control animals.The paradigm is that helper signals must be provided immediately upon antigen exposure, and their absence results in tolerance against the antigen.These data demonstrate that the time when CD4(+)T cell help signals must be provided is more dynamic and flexible than previously appreciated.

View Article: PubMed Central - PubMed

Affiliation: Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.

Show MeSH
Related in: MedlinePlus