Identification and characterization of autoantibody-producing B220(low) B (B-1) cells appearing in malarial infection.
Mice with malaria showed unique immunological responses, including the expansion of NK1.1(-)TCR(int) cells (extrathymic T cells). Since TCR(int) cells with autoreactivity and autoantibody-producing B cells (B-1 cells) are often simultaneously activated under autoimmune conditions, it was examined whether B-1 cells were activated in the course of malarial infection. From days 14 after infection, B220(low) B-1 cells appeared in the liver and spleen. The number of B220(low) B cells was highest at day 14, but the ratio was highest at days 28-35. In parallel with the appearance of B220(low) cells, autoantibodies against HEp-2 cells and double-stranded DNA were detected in sera. These B220(low) cells had phenotypes of CD44(high), CD23(-) and CD62L(-). In sharp contrast, conventional B220(high) B cells (B-2 cells) were CD44(low), CD23(+) and CD62L(+). These results suggested that malaria immune responses were not mediated by conventional T and B cells but resembled the responses during autoimmune diseases.
Department of Immunology, Niigata University School of Medicine, Niigata 951-8510, Japan.
Yasuhiro
Y
Kanda
Hiroki
H
Kawamura
Hiroaki
H
Matsumoto
Takahiro
T
Kobayashi
Toshihiko
T
Kawamura
Toru
T
Abo
D000818:Animals; D000974:Antibodies, Antinuclear / Q000378:metabolism*; D015703:Antigens, CD / Q000096:biosynthesis; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism* / Q000469:parasitology / Q000473:pathology; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000469:parasitology / Q000473:pathology; D056945:Hep G2 Cells; D006801:Humans; D017493:Leukocyte Common Antigens / Q000096:biosynthesis; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008288:Malaria / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018512:Parasitemia; D010961:Plasmodium / Q000276:immunology* / Q000472:pathogenicity; D013154:Spleen / Q000473:pathology; D000637:Transaminases / Q000378:metabolism
D000974:Antibodies, Antinuclear; D015703:Antigens, CD; D000637:Transaminases; D017493:Leukocyte Common Antigens