Nifurtimox-induced alterations in the cell-mediated immune response to PPD tin guinea-pigs.

Positive skin reactions to PPD in guinea-pigs immunized with Freund's complete adjuvant (FCA) were reversed after treatment with 10 mg/kg/day nifurtimox for 12 days. The in vitro migration of peripheral blood leucocytes from FCA-immunized guinea-pigs was inhibited with PPD, but it returned to normal values after nifurtimox treatment. Furthermore, the cell-free supernatant from PPD-stimulated lymphocytes from FCA-immunized nifurtimox-treated guinea-pigs did not inhibit the migration of normal cells. Thus the administration of nifurtimox impaired the specific cell-mediated immune response to PPD both in vivo and in vitro.