Cell-mediated immune response following Mycoplasma pneumoniae infection in man. I. Lymphocyte stimulation.

Abstract

Lymphocytes from seventeen cases of recent Mycoplasma pneumoniae infection, thirteen cases of previous infection and ten healthy subjects lacking antibodies to M. pneumoniae were cultured in the presence of various antigen preparations of M. pneumoniae. Lymphocyte stimulation was measured by the uptake of [(14)C]thymidine and by counting of morphologically transformed cells. The lymphocyte response to a sonicated concentrate of M. pneumoniae organisms and to a membrane fraction was significantly higher in recently infected patients than in healthy controls. However, nine out of ten serologically negative controls showed some degree of lymphocyte reactivity to M. pneumoniae. A lipid fraction of M. pneumoniae, which had a high antigen titre in the complement fixation test, induced no appreciable stimulation of lymphocytes from infected cases or control subjects. Lymphocyte responsiveness to sonicated M. pneumoniae antigen was demonstrable up to 10 years after infection. Among the cases with recent or previous M. pneumoniae infection there was no correlation between the degree of lymphocyte stimulation and the titres of antibodies to M. pneumoniae.