Lymphocyte transformation during dinitrochlorobenzene contact sensitization. An in vitro and in vivo evaluation of the primary immune response in man.

An evaluation of cell-mediated immunity in man is described that combines the advantages of an in vitro technique, lymphocyte transformation, with the use of contact sensitization to a primary immunogen, dinitrochlorobenzene (DNCB). DNCB, when coupled to autologous or allogeneic peripheral blood leukocytes, forms a complex, DNCB-antigen, that induces lymphocyte transformation specifically in leukocyte cultures from subjects sensitized to DNCB. Sequential studies of lymphocyte transformation to DNCB-antigen show that specifically reactive lymphocytes are first detected at about 10 days after in vivo application of a sensitizing dose of DNCB and reach a peak at about 14-21 days.