Resumen

LAURENTI, M.D. et al. The role of natural killer cells in the early period of infection in murine cutaneous leishmaniasis. Braz J Med Biol Res [online]. 1999, vol.32, n.3, pp. 323-325. ISSN 1414-431X.  http://dx.doi.org/10.1590/S0100-879X1999000300012.

In order to study the role of natural killer (NK) cells during the early period of Leishmania infection, BALB/c mice were selectively and permanently depleted of NK cells by injection with ⁹⁰Sr and subsequently infected with Leishmania (Leishmania) amazonensis (HSJD-1 strain). ⁹⁰Sr is known to selectively deplete NK cells, leaving an intact T- and B-cell compartment and preserving the ability to produce both interferon alpha and IL-2. This method of depletion has advantages when compared with depletion using anti-NK cell monoclonal antibodies because the effect is permanent and neither activates complement nor provokes massive cell death. In the present study, after one month of treatment with ⁹⁰Sr, the depletion of NK cells was shown by a more than ten-fold reduction in the cytotoxic activity of these cells: 2 x 10⁶ spleen cells from NK-depleted animals were required to reach the same specific lysis of target cells effected by 0.15 x 10⁶ spleen cells from normal control animals. The histopathology of the skin lesion at 7 days after Leishmania infection showed more parasites in the NK cell-depleted group. This observation further strengthens a direct role of NK cells during the early period of Leishmania infection.

Palabras llave : cutaneous leishmaniasis; NK cells; strontium 90; Leishmania (Leishmania) amazonensis.