CORRELATION BETWEEN HUMAN CYTOMEGALOVIRUS QUANTITATIVE P72 ANTIGENEMIA AND VIREMIA

Objective: We present a prospective study of the correlation between t he human cytomegalovirus (HCMV) quantitative antigenemia with monoclon al antibody to p72 protein (immediate-early antigen) and the number of infected cell foci detected iii the shell-vial culture. A comparative study was made of the value of quantitative antigenemia (pp65 and p72 ) in 14 patients. Results: The average value of the pp65 antigenemia w as 195 pp65-positive PMNLs per 10(5) PMNLs (range 10-1000) and that of the p72, 21 p72 positive PMNLs per 10(5) PMNLs (range 0-120) (P<0.001 ). The p72 antigenemia value represented 10.7% of the pp65 value (rang e 4.4-70%). A statistical correlation was observed between the total n umber of infected cell foci detected in the shell-vial culture and the total number of p72-positive PMNLs (P<0.001), but not with the number of pp65-positive PMNLs (P=0.4). A study of the number of infected cel l foci detected in the shell-vial per 100 000 PMNLs inoculated showed a statistical correlation with the value of the p72 antigenemia (P<0.0 01). Conclusions: According to results, there seems to be a general po pulation of PMNLs carrying viral particles which are detected by means of the pp65 monoclonal antibody, and a subpopulation carrying active and replicative viral particles which is detected with the p72 antibod y. This last subpopulation would be responsible for the formation of i nfected cell foci in the shell-vial culture. However due to the techni cal difficulties presented by the routine performance of p72 antigenem ia, we recommend the routine application of the quantitative shell-via l culture and the use of the number of infected cell foci x 100 000 PM NLs inoculated as a parameter of replicative viral load for the diagno sis of infection and disease caused by HCMV.