Figure 4. Augmentation of long-lasting CD4⁺ T cell (effector/central) memory response upon immunization of mice with archaeosome encapsulated Rv 3619c.

After 8 weeks post challenge, the splenocytes were isolated from various immunized groups and analyzed for the presence of CD44^high, CD62L^low/high on gated CD4⁺ T cells by FACS (A). The gated CD4⁺ T cells belonging to various immunized groups are denoted in the upper panel. Various experimental groups included in the study are: BCG (a) Sham (antigen free) archaeosome as control (b) Free Rv3619c Ag (c) Sham archaeosome + free Rv3619c Ag, a physical mixture (d) Archaeosome entrapped Rv3619c Ag (e) and isotype control (f). Lower panel indicates the analysed memory markers belonging to the corresponding CD4⁺ T cells in the upper panel. Bars indicate the total number of (CD4⁺ CD44^high CD62L^low/^high) (B). The data were analyzed with the Student's t test and are shown as the means (±S.D.) of 2 independent experiments. Archaeosome Vs BCG p<0.001 CD4⁺ (CD44^high, CD62L^low and CD62L^high); physical mixture Vs BCG p = NS CD4⁺(CD44^high, CD62L^high), p<0.01 (CD4⁺CD62L^low); archaeosome Vs free Ag p<0.001 CD4⁺(CD44^high, CD62L^high, and CD62L^low).