A possible non-oncogenic effect of C type bone cell virus on serum calcium levels of potentially leukemic mice

In bone of C3H/Fg mice, particles structurally identical to C-type leukemia virus arise from membranes of osteocytes and osteoblasts. Although these virus apparently do not induce morphologic or neoplastic change in bone they may have other, more subtle, effects. Thus, comparison of sera from male C3H/Fg mice, a high leukemia-prone strain, with C57BL and C3H/HeJ mice, low leukemia strains which do not contain C-type virus in bone, reveals that serum calcium levels are significantly lower in the former than in the latter. Further, when C3H/Fg mice develop frank leukemia there is a corresponding increase in virus particles while the serum calcium concentration levels fall to even lower values. The presence of leukemia itself appears not to be the cause as indicated by the failure of implanted lymphocytic leukemic cells in C3H/Fg mice to significantly affect serum calcium concentration. It is postulated that the effects of the virus could be due either to increased osteo blastic activity or to inhibition of osteocytic osteolytic activity or to both.