T cells from mice immunized either intraperitoneally or orally with CVB4/p24(73₃) produce cytokines in response to gag p24 peptides.

<p>Splenic CD4 and CD8 T cells producing TNF-α, IL-2, or IFN-γ in response to p24(65–73) or p24(10–30) were identified by multiparameter flow cytometry. (A) Primary immune responses after immunization via the intraperitoneal route. (B) Secondary immune responses after immunization via the intraperitoneal route. (C) Secondary immune responses after immunization via the oral route. Each symbol represents the results from one experiment using splenocytes pooled from 3 mice. Experiments were done a total of three or four times and all of the data are shown here. Mean values are indicated by horizontal bars. Flow cytometric analysis was performed after gating on CD4 or CD8 T cells. The T cell frequency indicates the percentage of CD4 or CD8 T cells that is responding to the gag p24 peptides. T cell frequencies after IP immunization with one or two doses of virus were similar. The one exception is indicated by a closed arrowhead (P<0.05). T cell frequencies after IP or oral immunization with two doses of virus were also similar. The one exception is indicated by an open arrowhead (P<0.05). Statistical analysis was done using a one-way ANOVA. The functionality of gag p24-specific T cell responses was assessed using Boolean gating and FlowJo software, and the data is shown in pie charts. Polyfunctional T cells were detected after IP immunization but not after oral immunization.