Figure 2. Germinal center responses following 2^nd Env trimer immunization.

(A) Immunization and sampling schedule of 2^nd immunization. Groups were immunized and sampled contemporaneously.

(B) Frequencies of total B_GC cells over time.

(C) Env trimer-specific B cell frequencies over time.

(D-E) Env trimer-specific B_GC cells over time.

(F) High-affinity Env trimer-specific B_GC cells over time.

(G) High-affinity Env trimer-specific B_Mem cells over time.

(H) GC-T_FH cell frequencies after 2^nd immunization.

(I) Representative flow cytometry of Env-specific CD4⁺ T cells from LNs. Cells were left unstimulated or stimulated with a peptide pool spanning Olio6_CD4ko.

(J) Env-specific CD4⁺ T cells at w12 (bolus) or w14 (OP).

(K) Representative flow cytometry of GC-T_FH, mantle (m)T_FH and non-T_FH cell subsets.

(L) Flow cytometry of AIM_OB assay (OX40⁺4-1BB⁺), gated on GC-T_FH, mT_FH or non-T_FH cells.

(M) Quantification of Env-specific CD4⁺ T cells by subset.

Mean ± SEM are graphed. Statistical significance tested using unpaired, two-tailed Mann-Whitney U test. *p≤ 0.05, **p≤0.01, ***p≤0.00. See also Figure S2.