Killing of Escherichia coli strains from clinical specimens in human serum and polymorphonuclear leucocytes.
Hundred Escherichia coli strains were collected from extra-intestinal and intestinal disease for the present study. Of the strains isolated 49 (49%) were serum sensitive and 47 (47%) serum resistant. The remaining 4 (4%) strains showed intermediate sensitivity to the pooled normal human serum (PNHS). Strains isolated from faeces were significantly more sensitive than strains of extra-intestinal origin (P<0.01). Response of Escherichia coli strains to killing by polymorphonuclear leucocytes was seen in 50 isolates (50%). Faecal strains showed significantly more intracellular killing as compared to extra-intestinal strains (P<0.01). Thus, clinical significance of Escherichia coli strains from different sources can be determined by the resistance to the bactericidal effect of human serum and killing in polymorphonuclear leucocytes.
Kumar
Surinder
S
Department of Microbiology Department, Maulana Azad Medical College, New Delhi.
Rizvi
Meher
M
D001770:Blood Bactericidal Activity; D004926:Escherichia coli / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D007223:Infant; D009504:Neutrophils / Q000502:physiology*; D010587:Phagocytosis; D014774:Virulence