Production of interferon gamma in cultures of whole blood obtained in the course of and after healing of cutaneous leishmaniasis

Whole-blood cultures from individuals with cutaneous leishmaniasis due to Leishmania major, tested under field conditions, showed a good correlation between the production of interferon-gamma and total blood lymphocyte proliferation (TLP), assayed by response to specific leishmania antigen. A group of patients, re-tested on several occasions, converted to positive in both parameters of cell mediated immunity (CMI) at the same time. It is suggested that the TLP assay and the production of interferon-gamma detect similar CMI activity in human cutaneous leishmaniasis. The measurement of interferon-gamma production has the advantage over the TLP assay that the supernatants of the cultures can be frozen and stored for prolonged periods before the assay is performed. For this reason, this could present a suitable method for field studies.