Baboon T cell lymphomas expressing the B cell-associated surface proteins CD40 and Bgp95.
Papio hamadryas baboons in the Sukhumi colony develop enzootic outbreaks of malignant lymphomas with an incidence of about 1.5% per year among adults of the high-risk stock. We investigated the surface phenotypes of cells from normal and lymphomatous animals using antibodies against human lymphocyte antigens. We found that more than 80% of the lymphomas that developed during the last 3 years were characterized histologically to be of the peripheral T cell type. Generally, the lymphomatous cells also expressed high levels of MHC class II DR protein, CD18 (LFA-1 beta chain), and CD45RO. Surprisingly, these cells also expressed on their surface two proteins previously characterized as being relatively B cell-restricted: CD40 and Bgp95. These proteins were never found on the peripheral blood T cells from normal animals. The expression of these two gene products was confirmed by RNA blotting and immunoprecipitation. In most cases, the two B cell-associated proteins were expressed on the predominant T cell subsets; we found both B cell proteins on CD4+, CD8+ as well as on the CD4/8 double-positive cells when these subsets were expressed at high levels. About 90% of these animals are seropositive for Herpesvirus papio and human T cell leukemia virus-1 (HTLV-1) before developing outright lymphomas. In all of the lymphoma samples, HTLV-1 tax DNA sequences were detected by PCR amplification. Whether or not HTLV-1 or the Herpesvirus papio gene products influence the surface expression of CD40 and Bgp95 remains to be determined.
Indzhiia
L V
LV
Institute of Experimental Pathology and Therapy, USSR Academy of Medical Sciences, Sukhumi.
Yakovleva
L A
LA
Overbaugh
J
J
Licciardi
K A
KA
Chikobava
M G
MG
Klotz
I N
IN
Torres
R
R
Indzhiia
V O
VO
Lapin
B A
BA
Clark
E A
EA
D000818:Animals; D015703:Antigens, CD / Q000032:analysis*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis*; D000954:Antigens, Surface / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D019013:CD40 Antigens; D005434:Flow Cytometry; D016355:Genes, pX / Q000276:immunology; D015490:HTLV-I Infections / Q000276:immunology; D006568:Herpesvirus 1, Cercopithecine / Q000276:immunology; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000276:immunology; D016130:Immunophenotyping; D016399:Lymphoma, T-Cell / Q000276:immunology / Q000662:veterinary*; D008969:Molecular Sequence Data; D008992:Monkey Diseases / Q000276:immunology*; D010215:Papio; D016133:Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface; D019013:CD40 Antigens