Figure 1.

n-Butyrate induced anergy in T helper type 1 (Th1) cells. Th1 cells were stimulated with keyhole limpet haemocyanin (KLH) in the presence or absence of n-butyrate in primary cultures. (a) Following 24 hr in the primary cultures, proliferation was measured as a function of [³H]thymidine incorporation. (b) Following 6 days in primary cultures, Th1 cells were isolated, and along with previously untreated Th1 cells, were stimulated in equivalent numbers for 24 hr with KLH or with interleukin-2 (IL-2) -containing conditioned medium. Proliferation results are presented as mean ± standard error. This experiment was repeated nine times with similar results. Asterisk indicates statistical difference between anergic and control Th1 cells. (c) Following 6 days in primary cultures, Th1 cells were isolated and were stimulated in equivalent numbers for 24 hr with anti-CD3 and anti-CD28 antibody-coated beads at a 1 : 4 bead to cell ratio or with IL-2-containing conditioned medium. (d) Following 6 days in primary cultures, Th1 cells stimulated with antigen ±n-butyrate were restimulated with anti-CD3 and anti-CD28 antibody-coated beads at a 1 : 1, 1 : 2 or 1 : 4 bead to cell ratio for 24 hr. Culture supernatants were collected and IL-2 and interferon-γ levels were measured.