EN
Elimination of measles is one of the priority plans ofWHO. The success of this plan depends on the development of long lasting, postvaccinal immune response. The aim of this study was to present the effect of stimulation with different strains of measles virus on the expression of T-helper cell (CD4+ T) early activation markers in people with different history of measles infection and to determine the correlation between the activation and dose of virus used for stimulation. The study was conducted using material derived from two patients: one seropositive due to natural infection and one vaccinated, with traces of anti-MeV IgG antibodies. In the CD4 T helper cells, the expression of CD69 receptor and the ability of the cells to produce INF after stimulation with the vaccine-derived or wild-type strain of measles virus was determined. For antigen-specific stimulation the virus suspension containing about 100 infectious particle, its tenfold and hundredfold dilutions was used. We found that the expression of T-helper cells early activation markers depended on the strain of the measles virus used for the stimulation, type of the immune response (postvaccinal, natural infection), and in the case of CD69 expression also on the dose of the virus used for the stimulation.