Incorporation of 14C-thymidine in human platelets: possible relation with a diffuse infection of micrococci in the L form.

Following the results of previous researches suggesting that platelets might carry microbial forms, the incorporation of 14C-thymidine in suspensions of platelets from 500 normal human subjects has been taken under examination. The results have always yielded positive data even though with marked differences of a quantitative order from a case to another. The hypothesis that such an activity might be the consequence of a synthesis of DNA in the mitochondria had to be excluded. The peculiar relations linking the incorporation rate to the number of platelets and to the presence of plasma or serum in given amounts and the strong inhibition exerted by oxytetracyclines suggest that the detected metabolic activity may be attributed to the presence of bacterial L-forms carried by platelets. The results of cultural, optical and electron microscopical investigations, which will be published elsewere, confirmed such interpretation.