Theileria annulata in CD5(+) macrophages and B1 B cells.
Theileria parasites infect and transform bovine leukocytes. We have analyzed laboratory-established Theileria sp.-infected leukocyte lines and observed that transformed macrophages express CD5. Low-level expression of CD5 by macrophages was further confirmed on three independent Theileria annulata clinical isolates from Tunisia. Interestingly, the fourth CD5(+) clinical isolate (MB2) was morphologically different, expressed surface immunoglobulin M (IgM) and BoLA class II, and had rearranged Ig light-chain genes. To demonstrate that MB2 did indeed contain CD5(+) B cells, individual clonal lines were obtained by limiting dilution, and CD5 expression and Ig gene rearrangement were confirmed. This suggests that in natural infections T. annulata can invade and transform CD5(+) B cells.
Moreau
M F
MF
URA CNRS 1960, Department of Immunology, Pasteur Institute, 75724 Paris Cedex 15, France.
Thibaud
J L
JL
Miled
L B
LB
Chaussepied
M
M
Baumgartner
M
M
Davis
W C
WC
Minoprio
P
P
Langsley
G
G
D000818:Animals; D016175:B-Lymphocyte Subsets / Q000469:parasitology*; D018956:CD5 Antigens / Q000032:analysis*; D002460:Cell Line; D005434:Flow Cytometry; D006801:Humans; D008264:Macrophages / Q000276:immunology / Q000469:parasitology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016796:Theileria annulata / Q000472:pathogenicity*; D013801:Theileriasis / Q000469:parasitology*
D018956:CD5 Antigens