Farzaneh Zarrinkar, Ali Khamesipour, Akram Miraminmohammadi, Ebrahim Eskandari, Mahmoud Nateghi Rostami, Esmaeil Fallah,
Volume 3, Issue 3 (9-2012)
Background and Aim: Leishmanization (LZ) is an effective tool to prevent
cutaneous leishmaniasis. Standardization of Leishmania is
the main drawback of LZ. The aim of this study was to assess the effect of
various preservatives on the infectivity of Leishmania.Methods: L.major harvested
at different stages of growth logarithmic, early and late stationary phases
were frozen using various preservatives of saccharose, glycerol, trehalose,
glucose, sorbitol, and dimethyl sulfoxide (DMSO). The harvested parasites were
inoculated into BALB/c mice before and after freezing. The infectivity of the
parasites was checked. IFA test was used to assess the rate of metacyclic
parasite.
Results: The ratio of
live Leishmania in different growth stages and various
preservatives were 89.0% to 98.2%. The lesion development in groups of mice
which received Leishmania in sacarose + glycerol or DMSO was started from 3rd
week and at 5th week all the mice showed lesion. The group of mice
which were inoculated with early or late stationary phases in saccharose +
glucose, saccharose + glycerol, glycerol 15% or DMSO showed lesion from 4th
to 5th week and in 100% showed lesions at 8th week. The
rate of metacyclic parasites increases from log phase to early and late
stationary phases.
Conclusion: There was a
correlation between percent of live parasite and the rate of lesion development
in BALB/c mice. Saccharose 22.5% + Glyserol 22.5% were the most appropriate preservative to freeze L. major. IFA
test is used to detect metacyclic Leishmania. A correlation was seen between the rate of
lesion development in BALB/c mice and IFA positivity.
