Human lymphocyte responses against epitopes of a self antigen: a follow-up at different time points

This study was aimed at examining the changes that may occur with time in the lymphocyte responses of an individual against peptide determinants of self antigens. Peripheral blood lymphocytes were collected from the same donor at seven different time points during a 10-month period and tested for their proliferative responses against whole human S-antigen and 40 overlapping peptides derived from the sequence of this uveitogenic retinal protein. Lymphocytes collected at different dates varied in their responsiveness to all tested antigens, as well as in the pattern of their response against individual peptides. The latter variability was expressed by differences in the hierarchical order of the most stimulatory peptides for lymphocytes collected at the seven time points. Despite the variability in their stimulatory capacity, six of the peptides exhibited their immunodominance by eliciting proliferation in lymphocytes collected at all time points. Our results thus indicate that data collected from a single sample of blood may be insufficient to accurately assess the level of cellular response to autologous antigens.