Fig. 5.

Proliferation of T lymphocytes using polymorphonuclear neutrophils (PMN) as antigen-presenting cells: (a) PMN derived from the lavage of patient 12 (L-PMN, 1 × 10⁵) were co-cultivated with either lavage-derived T cells (L-T cells) or T cells isolated from the peripheral blood (pT cells, 2 × 10⁴) (taken immediately prior to surgery) in the absence (two left columns) or presence (two right columns) of staphylococcal enterotoxin (SE) A (10 ng/ml); proliferation was measured by incorporation of [³H]-thymidine (cpm). Values represent the mean ± s.d. of 12 parallel wells. *Indicates that proliferation is different from that seen in the absence of SEA (P = 1·5 × 10⁻⁸); **proliferation of pT cells is enhanced compared to L-T cells (P = 1·2 × 10⁻⁸). (b) CD4 positive T cells (obtained from the lavage of patient 11) were cultivated in the presence of heterologous PMN and either SEA or SEB in the concentrations indicated; proliferation of T cells was measured at day 4. (c) A similar experiment using CD8 positive T cells. The values represent the mean ± s.d. of 12 parallel wells [please note that in the experiments shown in (b) and (c) five times more cells were used]. (d) CD8 positive T cells (derived from the lavage of patient 11) were cultivated in the presence of autologous PMN and SEA (10 ng/ml). After 24 h, synthesis of IFN-γ was measured by cytofluorometry of permeabilized cells (line IgG isotype control; filled peak anti-IFN-γ).