Table 2.

Percentage of CD4⁺ T cells positive to intracellular cytokines

	CD57+ cells		CD57− cells
	Mycobacterial antigen	Con A mitogen	Mycobacterial antigen	Con A mitogen
IL-4+	19.7 ± 3.2*	69.7 ± 4.5	0.9 ± 0.2*	22.5 ± 2.6
IFN-γ+	24.7 ± 2.5†	75.2 ± 4.4	5.8 ± 0.8†	21.4 ± 3.6

Flow cytometry analysis for CD4⁺ T cells co-cultured with autologous monocytes for 72 hr in the presence of mycobacterial antigen (3 µg/ml). Concanavalin A (Con A) (2 µg/ml) was used as the cell-activation control. At the end of the co-culture, CD4⁺ T cells were incubated with antibodies to CD57, interleukin-4 (IL-4) and interferon-γ (IFN-γ) for anaysis using three-colour immunofluorescence assays, as described in the Materials and methods. The percentage of positive cells was obtained from at least five samples for each group, and data are expressed as mean values ± standard error. Statistically significant differences were found in the comparison between CD57⁺ cells and CD57⁻ cells from the group of tuberculosis patients

^*,†P < 0.001.