Fig. 1.

Production of T cell lines from endarterectomy plaque material following mitogenic or antigenic stimulation. Plaques from patients were divided into 48 replicate cultures and 12 wells stimulated with either phytohaemagglutinin (PHA), PPD, tetanus toxoid (TT) or Chlamydia trachomatis (Ct) plus IL-2. Wells in which outgrowth of T cells was visible microscopically were assayed for T cell proliferative responses to antigen or mitogen in the presence of irradiated autologous peripheral blood mononuclear cells (PBMC). Wells in which T cells gave a proliferative response > 10 000 ct/min following PHA restimulation were scored positive as having produced T cell lines. Results show the proportion of wells (overall mean values) giving rise to T cell lines for each of the stimuli used in the initial cultures. Although PHA was significantly better at allowing establishment of T cell lines from biopsy material (P > 0·05), there were no significant differences between the three recall antigens in their ability to produce T cell lines (P < 0·05).