The distribution of T-cell responses in different immune sites after intranasal BCG vaccination.

The distribution of M. tuberculosis whole cell lysate (WCL) and short term culture filtrate (STCF) specific T-cells in local and peripheral immune compartments of BALB/c mice was investigated at 30 weeks after intranasal BCG vaccination. The frequencies of IFN-γ and IL-4 secreting cells in lungs, spleen, cervical lymph nodes (CLN), peritoneal cavity (PC), bone marrow (BM), mesenteric lymph nodes (MLN), and inguinal lymph nodes (ILN) were enumerated by ELISPOT assay. The frequencies are expressed as spot forming units (SFUs)/million cells after in vitro stimulation of 1×105 cells/well from each organ for 36–40 h in the presence of BM-DCs at the ratio of 5∶1 organ cells/DC. The results are calculated as means ± standard deviation of three to six determinations of pooled cells from four mice after subtracting the SFUs from respective unstimulated cultures.