Heat shock response of Babesia divergens and identification of the hsp70 as an immunodominant early antigen during ox, gerbil and human babesiosis.
Using antisera (alpha-R and alpha-C7Ag) directed against the conserved Gly-Gly-Met-Pro-epitope of the hsp70 family, a single antigen was identified in the human Babesia divergens Rouen 1987 isolate by Western immunoblotting and immunoprecipitation experiments. This B divergens hsp70 is highly conserved as shown by the analysis of five other geographical B divergens isolates from different hosts (human and bovine). Indirect immunofluorescence assay performed on the asexual intraerythrocytic stages showed that the hsp70 is mainly cytoplasmic and stage-independent. Heat-shock experiments, with 20 min incubation at 40 degrees C followed by a 10 to 50 min shift to 37 degrees C in the presence of [35S]-methionine, led to an increase of two hsp of 85 and 70 kDa while protein synthesis in general decreased within 10 min. Immunoprecipitations of [35S]-methionine radiolabelled proteins with human, ox and gerbil antisera raised against various B divergens isolates, showed the presence of a B divergens 70 kDa protein which was demonstrated to be a hsp70 by coupling immunoblotting assays with alpha-C7Ag serum on the same immunoprecipitated material. During human babesiosis, the B divergens hsp70 appears as an early antigen during the acute phase. These results are in agreement with the use of the B divergens hsp70 as an essential valence antigen in an anti-babesiosis vaccine.
Carcy
B
B
URA CNRS 290J, Université de Poitiers, France.
Précigout
E
E
Valentin
A
A
Gorenflot
A
A
Reese
R T
RT
Schrével
J
J
D000595:Amino Acid Sequence; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology*; D001345:Autoradiography; D001403:Babesia / Q000276:immunology*; D001404:Babesiosis / Q000276:immunology* / Q000469:parasitology; D015153:Blotting, Western; D002417:Cattle; D003429:Cross Reactions / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D005849:Gerbillinae; D006360:Heat-Shock Proteins / Q000276:immunology*; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology*; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000276:immunology
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D006360:Heat-Shock Proteins; D016056:Immunodominant Epitopes