Antibody formation to double-stranded DNA in nu/nu and nu/+ mice

Antibody formation to double-stranded (ds-) DNA in nude mice (nu/nu) and normal littermates (nu/+) was studied using a Millipore filter method. The mean antibody titre to ds-DNA in the sera of nu/nu mice was generally higher than that in nu/+ mice raised in the same environment. However, in both genotypes, anti-ds-DNA titres varied according to the environmental condition in which the animals were raised. Mice maintained germ-free showed no significant antibody formation to ds-DNA. Nu/+ thymus and spleen cells passively transferred to nu/nu mice reduced the antibody titre to ds-DNA in the recipients. Immunochemical studies indicated that the antibodies to ds-DNA were IgM. It is suggested that T cell-mediated regulatory mechanisms control antibody formation to ds-DNA and that some infections trigger antibody formation to ds-DNA.