Trypanosoma congolense infections: antibody-mediated phagocytosis by Kupffer cells

Journal of Leukocyte Biology

Guojian Wei¹  Wanling Pan¹  Henry Tabel¹  Meiqing Shi¹ 

[1] Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

关键词: trypanosomes;    liver;    macrophages;    immunity;    cytokines;    immunohistochemistry;   

DOI  :  10.1189/jlb.1003500

学科分类：生理学

来源: Federation of American Societies for Experimental Biology

【 摘 要 】

Immunohistochemical double-label technique was used to detect trypanosomal antigen in macrophages. Immunoglobulin (Ig)M as well as IgG2a monoclonal antibodies (mAb) specific for the variant surface glycoprotein (VSG) mediated phagocytosis of Trypanosoma congolense variant antigenic type (VAT) TC13 by macrophages [bone marrow-derived macrophage cell line from BALB/c (BALB.BM)] in vitro. Administration of these IgM or IgG2a antibodies to BALB/c mice 30 min after injection of 3 × 108 T. congolense mediated phagocytosis of trypanosomes by Kupffer cells of the liver within 1 h. Plasma levels of the monokines interleukin (IL)-1β, IL-10, and IL-12p40 were significantly increased 6–48 h after phagocytosis. In BALB/c mice infected with 103 T. congolense, a small degree of phagocytosis of trypanosomes by Kupffer cells, mediated by actively synthesized antibodies, was detected as early as 5 days after infection. Phagocytosis of trypanosomes was dramatically enhanced on day 6. Concomitantly, the Kupffer cells trippled in size. In BALB/c mice infected for 6 days, treatment with IgM or IgG2a mAb specific for T. congolense VSG led to clearance of VAT TC13 parasitemia but did not prevent death at the second parasitemia of a different VAT. We conclude that IgM as well as IgG antibody mediate phagocytosis of trypanosomes by Kupffer cells.

【 授权许可】

Unknown