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Adoptive transfer of multivirus-specific T cell lines (MVST) is an advanced tool for immunotherapy of virus infections after hematopoietic stem cell transplantation (HSCT). Their preparation includes activation of donor virus-specific T cells by the mixture of oligopeptides derived from immunodominant antigens of several most harmful viruses, i.e. human cytomegalovirus (HCMV), polyomavirus BK (BKV), Epstein-Barr virus (EBV) and adenovirus (ADV). The aim of our study was to find out whether antigenic competition may have an impact on the expansion of virus-specific T cells. MVST from several heathy blood donors were generated using a pulse of overlapping oligopeptides (PepMixes™, derived from the IE1 and pp65 CMV antigens, VP1 and LTAG BKV antigens, BZLF1 and EBNA1 proteins of EBV and hexon protein from ADV) and short time culture in the presence of IL-7 and IL-4. The amount of virus-specific T cells in MVST was measured by ELISPOT and flow cytometry after re-stimulation with individual antigens. To evaluate antigenic competition, MVST were expanded either with a complete set of antigens or with the mixture lacking some of them. MVST expanded with the antigen mixture including CMV antigens contained a lower proportion of the T cells of other antigen specificities. A similar inhibitory effect was not apparent for EBV-derived peptides. The competitive effect of CMV antigens was most pronounced in MVST from CMV-seropositive donors and was mediated by both IE1 and pp65-derived peptides. Antigenic competition did not influence the phenotype of either CMV- or BKV-specific T cells. Both T cell populations had an effector memory phenotype (CD45RO+, CD27-, CCR7-). However, CMV-specific T cells preferentially consist of CD8+ while in BKV-specific T cells, the CD4+ phenotype predominated. Modification of the MVST manufacture protocol to prevent antigenic competition may increase the efficacy of MVST in therapy of BKV infections in HSCT recipients., (Copyright © 2020 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.)

Propolis is a generic name for a biological substance produced by bees used for multiple purposes in folk medicine. Propolis special extract GH 2002 is crude propolis highly purified by a special procedure and freed from the accompanying substances like pollen, wax, resins. The cytotoxic and antiherpetic effect of propolis extracts against Varicella zoster virus (VZV) was analysed in cell culture, and revealed a moderate cytotoxicity on lung fibroblasts with a CC 50 of 380 μg/ml. The 50 % inhibitory concentration (IC 50 ) of GH 2002 propolis extract for VZV plaque formation was determined at 64 μg/ml. The propolis extract exhibited high levels of antiviral activity against VZV in viral suspension tests, infectivity was significantly reduced by 93.9 % and a direct concentration-dependent antiviral activity could be demonstrated. In order to determine the mode of virus suppression by propolis, the extract was added at different times during the viral infection cycle. Addition of propolis to uninfected cells (pretreatment cells) prior to infection or to infected cells (replication) during intracellular replication had no or only minor effect on virus multiplication. However, propolis exhibited high anti-VZV activity when viruses were pretreated with propolis prior to infection thus indicating an unspecific interaction between the virus and propolis. The antiviral activity is comparable to acyclovir.

Objectives: To test diagnostic efficiency of a novel method for detection of IgM antibodies to VCA EBV. To compare sensitivity and specificity of detection of IgM antibodies to VCA EBV from patients at various stages of EBV infection by various serological methods., Material and Methods: IgM antibodies to VCA EBV were detected using IgM ELISA Viditest anti-VCA EBV IgM assay (Vidia, Ltd., Czech Republic) and comparative serological methods (indirect immunofluorescence assay, indirect ELISA (Human, SRN) and reverse ELISA (DiaSorin, Italy) in four independent diagnostic laboratories on panels of sera from 1) infectious mononucleosis patients, 2) patients with serological markers of EBV reactivation, 3) seropositive individuals lacking serological markers of active EBV infection, 4) seronegative individuals, 5) patients with IgM antibodies against another herpesvirus and 6) patients positive for rheumatoid factor. The sera yielding discrepant results were retested in the reference laboratory using the reference methods (indirect immunofluorescence and reverse ELISA). Overall, 854 IgM anti-VCA-positive or -negative sera were evaluated., Results: The sensitivity and specificity of the IgM Viditest anti-VCA EBV assay were 94.7 and 96.1 %, respectively. All of the three tests compared were similarly reliable in detecting IgM anti -VCA EBV antibodies in the samples from infectious mononucleosis patients. On the other hand, indirect fluorescence assay proved clearly superior to ELISAs for detection of IgM anti-VCA antibodies in the samples with serological pattern of EBV reactivation, typically showing significantly lower IgM anti-VCA titers compared with those from primary infection., Conclusions: The multilaboratory comparative study proved that the novel IgM ELISA-Viditest anti-VCA EBV assay (Vidia, Ltd., Czech Republic) which shows comparable diagnostic efficiency for detection of IgM EBV antibodies to viral capsid antigen (VCA) as compared to the other assays tested, i.e. ELISA (Human, Germany) and reverse ELISA (DiaSorin, Italy), is suitable for use in serological diagnosis of EBV.