Hemolysin Formation in Newborn Mice of Different Strains.

Abstract
Summary Newborn mice of AKR, Ha/ICR and C57Bl strains start to respond to immunization with sheep red blood cells at different ages (as measured by assays on circulating hemolysins and numbers of antibody-forming cells in spleen and lymph nodes). Once competence to respond has been attained, the magnitude of the response, in terms of numbers of antibody-forming spleen cells, is similar for all strains tested. However, there is no correlation between numbers of hemolysin-forming cells in the organs tested and circulating hemolysins. Only the latter parallel the strain differences in responsiveness observed by others in adult animals of these strains. When antigen is administered in conjunction with oligodeoxyribonucleotides, the early immune responses are enhanced, but the time of competence to respond to the antigenic stimulus is not advanced.