Effect of human milk on the mouse mammary tumor virus.

Abstract

Summary Mouse mammary tumor virus when mixed with whole, skimmed, or cream fractions of some human milks and incubated at 37° for 18 hr resulted in degradation of the particle morphology and decreased infectivity and reverse transcriptase activity of the virions. The cream fraction was more effective in the physical, biochemical, and biological degradation of the virions than the whole or skimmed milk, but the nature of the degrading component(s) has not been determined. The significance of the destructive effect of human milk upon mouse mammary tumor virus in relation to our search for the putative human breast cancer virus particles and reverse transcriptase activity in human milk isolates has been discussed.