Bovine CD18 Is Necessary and Sufficient To Mediate Mannheimia ( Pasteurella ) haemolytica Leukotoxin-Induced Cytolysis
| Autor: | Aruna P. N. Ambagala, Marcus E. Kehrli, Thanuja C Ambagala, Muralidhar S. Deshpande, S. Srikumaran |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Cytotoxicity
Immunologic DNA Complementary medicine.drug_class Immunology Integrin Exotoxins chemical and pharmacologic phenomena Transfection Monoclonal antibody Microbiology Cell Line Mice Neutralization Tests medicine Animals Lymphocyte function-associated antigen 1 Receptors Immunologic Mannheimia haemolytica Cellular Microbiology: Pathogen-Host Cell Molecular Interactions integumentary system Base Sequence biology RTX toxin Antibodies Monoclonal hemic and immune systems Molecular biology Lymphocyte Function-Associated Antigen-1 Recombinant Proteins Cytolysis Infectious Diseases Integrin alpha M Cell culture CD18 Antigens biology.protein Cattle Parasitology Dimerization |
| Zdroj: | Infection and Immunity. 70:5058-5064 |
| ISSN: | 1098-5522 0019-9567 |
| DOI: | 10.1128/iai.70.9.5058-5068.2002 |
| Popis: | Leukotoxin (Lkt) secreted by Mannheimia ( Pasteurella ) haemolytica is an RTX toxin which is specific for ruminant leukocytes. Lkt binds to β 2 integrins on the surface of bovine leukocytes. β 2 integrins have a common β subunit, CD18, that associates with three distinct α chains, CD11a, CD11b, and CD11c, to give rise to three different β 2 integrins, CD11a/CD18 (LFA-1), CD11b/CD18 (Mac-1), and CD11c/CD18 (CR4), respectively. Our earlier studies revealed that Lkt binds to all three β 2 integrins, suggesting that the common β subunit, CD18, may be the receptor for Lkt. In order to unequivocally elucidate the role of bovine CD18 as a receptor for Lkt, a murine cell line nonsusceptible to Lkt (P815) was transfected with cDNA for bovine CD18. One of the transfectants, 2B2, stably expressed bovine CD18 on the cell surface. The 2B2 transfectant was effectively lysed by Lkt in a concentration-dependent manner, whereas the P815 parent cells were not. Immunoprecipitation of cell surface proteins of 2B2 with monoclonal antibodies specific for bovine CD18 or murine CD11a suggested that bovine CD18 was expressed on the cell surface of 2B2 as a heterodimer with murine CD11a. Expression of bovine CD18 and the Lkt-induced cytotoxicity of 2B2 cells were compared with those of bovine polymorphonuclear neutrophils and lymphocytes. There was a strong correlation between cell surface expression of bovine CD18 and percent cytotoxicity induced by Lkt. These results indicate that bovine CD18 is necessary and sufficient to mediate Lkt-induced cytolysis of target cells. |
| Databáze: | OpenAIRE |
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