title: In vitro phagocytosis and killing of coliforms by bovine mammary leukocytes.
abstract: Four coliform isolates derived from cows with bovine mastitis-1 serum-sensitive (SS) Klebsiella pneumoniae, 1 intermediate serum-sensitive (IS) K pneumoniae, 1 IS Escherichia coli, and 1 serum-resistant (SR) E coli-were studied in vitro to determine factors associated with their phagocytosis and killing by leukocytes of mammae. The SS coliform was most easily phagocytosed, whereas the SR coliform was the least phagocytosed, and IS coliforms were ingested at an intermediate rate. The SS coliform was more readily killed in freshly collected serum alone, than by leukocytes and freshly collected serum or heat-inactivated serum. The IS coliforms were killed more readily by leukocytes with freshly collected serum, than by freshly collected serum alone or leukocytes and heat-inactivated serum. The extent of the killing of SR strain was equal for leukocytes with either freshly collected serum or heat-inactivated serum. The differences in killing of various coliforms in serum alone were not as great in a system including serum and leukocytes.
mesh_terms: D000818:Animals; D001770:Blood Bactericidal Activity; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood; D004755:Enterobacteriaceae / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology; D004927:Escherichia coli Infections / Q000097:blood / Q000662:veterinary; D005260:Female; D066298:In Vitro Techniques; D007710:Klebsiella Infections / Q000097:blood / Q000662:veterinary; D007711:Klebsiella pneumoniae / Q000276:immunology; D007962:Leukocytes / Q000502:physiology*; D008321:Mammary Glands, Animal / Q000166:cytology*; D008414:Mastitis, Bovine / Q000097:blood; D010587:Phagocytosis