Comparison of a quantitative microtiter method, a quantitative automated method, and the plate-count method for determining microbial complement resistance.
A quantitative microtiter method for determining the degree of complement resistance or sensitivity of microorganisms is described. The microtiter method is compared with a quantitative automated system and the standard plate-count technique. Data were accumulated from 30 avian Escherichia coli isolates incubated at 35 C with either chicken plasma or heat-inactivated chicken plasma. Analysis of data generated by the automated system and plate-count techniques resulted in a classification of the microorganisms into three groups: those sensitive to the action of complement; those of intermediate sensitivity to the action of complement; and those resistant to the action of complement. Although the three methods studied did not agree absolutely, there were statistically significant correlations among them.
Lee
M D
MD
Department of Medical Microbiology, College of Veterinary Medicine, University of Georgia, Athens 30602.
Wooley
R E
RE
Brown
J
J
Spears
K R
KR
Nolan
L K
LK
Shotts
E B
EB
D000818:Animals; D001770:Blood Bactericidal Activity; D002645:Chickens / Q000097:blood / Q000276:immunology*; D015169:Colony Count, Microbial; D003165:Complement System Proteins / Q000276:immunology*; D004926:Escherichia coli / Q000254:growth & development / Q000276:immunology*; D012044:Regression Analysis; D015203:Reproducibility of Results
D003165:Complement System Proteins