Abstract:
A laboratory based study was designed to characterize 43 cryo-preserved Leishmania-like
flagellates. These Leishmania-like flagellates were originally obtained from non-human
hosts that included spiny mice (Acomys subspinosus), plated lizards (Gerrosaurus major)
and sand flies of the Genus Sergentomyia caught at Masinga location, Machakos District
in Kenya. Morphological features and isoenzyme banding patterns of the flagellates were
studied. The isoenzyme markers which were used for isoenzyme electrophoresis included
Malate dehydrogenase (MDH), Phosphoglucomutase (PGM), Glucose phosphate isomerase
(GPI), Glucose 6-phosphate dehydrogenase (G6PD), Malic enzyme (ME), 6 phosphogluconate
dehydrogenase (6PGD) and Mannose phosphate isomerase (MPI). The isoenzyme banding
patterns of the flagellates’ lysates were compared with those of six WHO Leishmania reference
strains and those of seven well characterized reference strains of Trypanosoma, Crithidia,
Herpetomonas and Leptomonas species. The results showed that the morphological changes
of the Leishmania-like flagellates in the growth medium were indistinguishable from those
of Leishmania WHO reference strains used. The isoenzyme profiles of the flagellates were all
distinguishable from the reference strains used except for isolate NLB-1236 from G. major
which had an enzyme profile identical to that of L. tropica (NLB-305) in 6 enzymes (MDH, GPI,
MPI, ME, PGM, and G6PD). The banding pattern of isolate NLB-1261 from A. subspinosus was
indistinguishable from that of L. major (NLB-326) in 3 enzymes only (MDH, GPI and ME) while
isolate NLB-1231 from A. subspinosus had an enzyme profile identical to those of L. tropica
(NLB-305) and L. arabica (NLB-664) in six enzymes (MDH, GPI, ME, PGM, MPI, and 6PGD). More
than 80% of the Leishmania-like flagellates had enzyme profiles indistinguishable from each
other, in all the isoenzyme markers. The morphological traits of the flagellates suggested that
they were Leishmania or strains closely related to Leishmania. Isoenzyme analysis suggested
that Sergentomyia sand flies most likely feed on both lizards (reptiles) and rodents (mammals).
There is need to carry further investigations on NLB-1236 (from plated lizards), NLB-1261 (from
wild spiny mice) and NLB-1231 (from wild spiny mice).
