Comparison of Two Culture Media for the Isolation of Leishmania Strains

Abstract

Hendricks and Wright (1979, Am. J. Trop. Med. Hyg. 28: 962-964) showed that Schneider's Drosophila medium (GIBCO) plus 30% heat-inactivated, fetal bovine serum and antibiotics is more effective than the diphasic NNN medium for primary isolations of cutaneous species of Leishmania from humans. According to these authors, promastigotes are occasionally seen only 18 hours after inoculation because of the high sensitivity of Schneider's medium. Other reports (Childs et al., 1978, Intl. J. Parasitol. 8: 255-258; and Hendricks et al., 1978, Parasitology 76: 309-316) considered this medium faster, permitting higher yields for different species of Leishmania and other hemoflagellates, than the common diphasic media that use whole blood. We report here a comparison of the sensitivity of GIBCO Schneider's medium, used as indicated by Hendricks and Wright, against Senekjie's medium, according to Tobie and Rees (1948, J. Parasitol. 34: 162-163), for isolation of strains of cutaneous Leishmania from experimentally infected hamsters. We also used a variation of Senekjie's medium by adding proline (2.5 g/liter) to Locke's liquid phase instead of glucose. This modification was based on the observation that proline is considered a good energy source for some Leishmania (Steiger and Meshnick, 1977, Trans. Roy. Soc. Trop. Med. Hyg. 71: 441-443). We used 27 animals each previously inoculated subcutaneously in the nose with one of 15 strains of L. braziliensis of human origin, isolated in our laboratory, and two strains of L. peruviana provided by Dr. Aristides Herrer.