Quantitative inheritance of heterophile rheumatoid factor responsiveness in mice

A heterophile rheumatoid factor (RF) response to LPS was measured in mice by means of a plaque assay using target cells coated with bovine IgG. CBA mice were high responders and A, and DBA/2 were low responders, while strains C57Bl, and LP/J showed low to intermediate responsiveness. Use of appropriate congenic strains confirmed that responsiveness is not closely associated with either H-2 or Igh. Failure to respond is not likely to be due to a V-region deficiency, nor can it be readily circumvented, by heterosis (complementation) or the use of high doses of LPS or an extra virulent form of LPS. Breeding experiments show a quantitative trait with maternal responder status having a measurably positive effect.