Abstract
Trypanosoma evansi from buffalo, cattle and horse isolates were purified by Diethylaminoethyl cellulose
column chromatography. The purified trypanosomes from each sources were used separately for preparation
of whole cell lysate antigens. A comparative study on polypeptide pattern of whole cell lysate antigens of
these three isolates of T. evansi was studied. It showed a total of 11 dominant polypeptide bands with relative
molecular weight ranging from 95 to 13 kDa, when resolved in 10% sodium dodecyl sulphate
polyacrylamide gel electrophoresis and stained with Coomassie brilliant blue. Except some minor differences
between the relative molecular weight of isolates in a particular region, the polypeptide profiles of these
three isolates did not resolve any significant differences between them. Seven major polypeptides of relative
molecular weight ranges between 86-87, 74-75, 61-62, 51-53, 39, 34-35, 13 kDa and four minor
polypeptides ranges 93-95, 46-47, 28-29, 25-26 kDa appeared as common to all T. evansi of different hosts
origin and these were shared by all the isolates. A doublet band of relative molecular weight ranging between
86-87 kDa and 74-75 kDa appeared in the area between 66 and 97 kDa and a doublet band of relative
molecular weight 39 kDa and ranges 34-35 kDa also appeared in the area between 43 and 29 kDa in these
three isolates. It is opined from the result that antigenic variation due to change in VSG of T. evansi is not a
constant phenomenon. It is relative, depending on some intrinsic factors related to the physiological
environment of host and parasite.
