IgM antibody to filarial antigens in human cord blood: possibility of transplacental infection.

In a hospital in Sri Lanka, antifilarial antibody in maternal and umbilical cord blood was determined by indirect immunofluorescence, enzyme-linked immunosorbent assay and radio-immunoassay. Anti-filarial antibody was detected in 18 of 340 cord blood samples. Specific IgM antibody was detected in 12 cord blood samples. The foetal IgM antibody was probably in response to a transplacental transfer of filarial antigens. The exposure of the foetus to filarial antigens might be beneficial, increasing resistance to infection, or detrimental by inducing at least partial tolerance.