Lymphocyte transformation in presumed ocular histoplasmosis
J. P. Ganley, G. J. Nemo, G. W. Comstock and J. A. Brody
Lymphocytes from individuals with inactive macular disciform lesions of
presumed ocular histoplasmosis challenged with three histoplasmin antigens
incorporated tritiated thymidine at a significantly higher rate than
histoplasmin-stimulated lymphocytes of matched control and peripheral scar
groups. This finding is consistent with the etiologic association of the
disciform ocular syndrome and previous systemic infection with Histoplasma
capsulatum. The disciform group had a higher mean response than the other
two groups to pokeweed mitogen but not to phytohemagglutinin and had higher
mean counts per minute to the specific antigens Toxoplasma gondii,
Blastomyces dermatitidis, Cryptococcus neoformans, Mycobacterium
tuberculosis, M battery, and M gaus, but not to Candida albicans. These
data would suggest that individuals with the disciform lesion of presumed
ocular histoplasmosis have a hyperreactive cellular immune response; this
response may play an important role in the development of the disciform.
