Immune CD4+ T cells specific for Theileria parva-infected lymphocytes recognize a 24-kilodalton protein.
Theileria parva is a protozoan parasite that infects and transforms bovine lymphocytes. Here we report the partial purification of a T. parva-specific protein from infected lymphocytes that is recognized by CD4+ parasite-specific T-cell clones derived from immune cattle. T. parva-infected lymphocytes were homogenized in Dulbecco's phosphate-buffered saline in the presence of protease inhibitors. The antigen was purified from a postmicrosomal supernatant by using a combination of DEAE-cellulose chromatography and hydroxylapatite column chromatography. After labelling with 125I, the antigen preparation was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and found to contain 8 to 10 proteins. This preparation was subjected to chromatography in phosphate-buffered saline on HPLC TSK-250/125 columns coupled in tandem. A radiolabelled protein of M(r) 24,000 correlated with antigenic activity.
Grab
D J
DJ
International Laboratory for Research on Animal Diseases, Nairobi, Kenya.
Baldwin
C L
CL
Brown
W C
WC
Innes
E A
EA
Lonsdale-Eccles
J D
JD
Verjee
Y
Y
D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis / Q000276:immunology / Q000302:isolation & purification*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002417:Cattle; D008213:Lymphocyte Activation; D008970:Molecular Weight; D016797:Theileria parva / Q000276:immunology*
D000953:Antigens, Protozoan