Fig 7

(A and B) In vitro examination on the proliferation (A) and activation (B) of CD4⁺ T_SVCV cells isolated from zebrafish stimulated with inactivated SVCV (10⁶ TCID₅₀) and impaired by blockade of Env38 on APCs with anti-Env38 Ab (5 μg/ml) as determined by the CFSE dilution through FCM analysis and the transcriptional expression of cd154 and lck genes through RT-qPCR. (C and D) In vivo examination on the activation of CD4⁺ T cells stimulated with SVCV (10⁵ TCID₅₀) and impaired by blockade or knockdown of Env38 with i.p administering anti-Env38 Ab (10 μg/fish) or Env38siRNA-LV (1×10⁶ TU/fish) as determined by the percentage of CD4⁺CD154⁺ T cells with mouse anti-CD154 (1:500) and rabbit anti-CD4 (1:500) in leukocytes from spleen, head kidney and peripheral blood through FCM analysis (C) and the transcriptional expression of cd154 and lck genes through RT-qPCR (D). (E) In vivo examination on the proliferation of CD4⁺ T cells of zebrafish stimulated with SVCV (10⁵ TCID₅₀) and impaired by blockade or knockdown of Env38 with i.p administering anti-Env38 Ab (10 μg/fish) or Env38siRNA-LV (1×10⁶ TU/fish) as determined by the percentage of CD4⁺EdU⁺ T cells with rabbit anti-CD4 (1:500) in leukocytes from spleen, head kidney and peripheral blood as determined by FCM analysis. Nonrelated control groups were administered with isotype IgG or scrambled siRNA-LV. Negative control groups received mock PBS. The data presented in each block diagram indicated the average percentage of CD4⁺CD154⁺ T cells or CD4⁺EdU⁺ T cells in each treatment group. RT-qPCRs were run in combination with the endogenous β-actin control. Error bars represented SEM. (*p < 0.05; **p < 0.01; ***p < 0.001; ns, no significant difference).