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A C WARDLAW

Publications and source records attributed to A C WARDLAW.

At least 19 recordsLinked to original sources
PubMed1964

DISTRIBUTION, INHERITANCE, AND PROPERTIES OF AN ANTIGEN, MUB1, AND ITS RELATION TO HEMOLYTIC COMPLEMENT.

An antigen, MuB1, present in the sera of some mice, can elicit a precipitating antibody in certain other strains of mice. An antibody to the antigen MuB1 can also be elicited in rabbits. 99 strains and substrains of inbred mice were tested for the presence of MuB1; the antigen was found in the sera of 44 strains (61 per cent) and 14 DBA substrains (52 per cent). Evidence is presented indicating that mice lacking MuB1 do not make a modified antigen, corresponding to MuB1, but are genetically deficient in synthetic ability at this site. By reaction with antibody to MuB1 an antigen corresponding to MuB1 was found in 13 of the 15 orders of mammals, and in 63 of 85 mammalian species tested, including man and guinea pig. The quantity of the antigen MuB1 is always greater in the serum of male than in the serum of female mice. The concentration of MuB1 increases with age; this increase is more marked in male than in female mice. By means of backcross experiments it was shown that the inheritance of MuB1 is unifactorial, is independent of the inheritance of the gamma globulin allotype MuA2, and is qualitatively independent of the sex of the parents. The antigen MuB1 is found in the euglobulin fraction of serum; it loses its ability to precipitate with antibody after heating at 56 degrees C, but not after treatment with ammonia or hydrazine. By gel filtration, MuB1 is separated with a fraction containing molecules of molecular weight approximately 150,000. An empirical correlation was observed between the presence or absence of MuB1 in the sera from inbred mice and the presence or absence of hemolytic complement (Hc), as measured by a test using a high concentration of rabbit hemolysin. In backcross experiments also, a correlation between hemolytic complement and the presence of MuB1 was demonstrated. As with MuB1, male mice had a higher hemolytic complement level than females. The particular component of complement which may be identical with MuB1 has not been identified.

Animals↗
PubMed1962

The complement-dependent bacteriolytic activity of normal human serum. I. The effect of pH and ionic strength and the role of lysozyme.

The bacteriolytic activity of normal human serum on a rough strain of E. coli has been studied by a turbidimetric method. Bacteriolysis was found to be markedly dependent on ionic strength and pH, with optima at micro = 0.06 and pH 8.3-8.5, respectively. The method of cultivating the cells also influenced the rapidity of lysis. Lysis was temperature-dependent and was exhibited by all samples of human serum tested. Microscopically, organisms incubated with serum were observed to swell, loose their rod shape and eventually burst, leaving remnants of the cell membrane in suspension. Sphaeroplasts were obtained by brief exposure of cells to serum followed by dilution into 5 per cent sucrose. The bacteriolytic reaction was shown to require complement. No definite requirement for properdin or specific antibody in this system could be demonstrated by the absorption of serum with zymosan and with homologous cells respectively. The latter procedure was found to reduce bacteriolytic activity by removal of serum lysozyme. Absorption of serum with bentonite also led to loss of bacteriolytic activity which could be restored with lysozyme. The organism was not lysed by lysozyme alone, but lysis occurred with lysozyme + EDTA in tris buffer. The possibility of complement acting independently of antibody or properdin, in certain instances, is discussed in relation to bacterial cell wall structure. Data are presented supporting the hypothesis that the "substrate" of complement in cell membranes is a lipid or lipoprotein.

Antibodies↗