Evaluation of different assay techniques to assess the interaction between Leishmania major and L. infantum promastigotes and U937 cells.

: Adherence of Leishmania major and L. infantum promastigotes to U937 cells was determined by microscopic observation or by using radiolabelled parasites. With both methods L. infantum showed a greater adherence. Aspecific attachment to plastic was greater for L. major. The possible implications of these findings in connection with disease pathogenesis are briefly discussed.