Profile of natural killer cells after a previous natural Vaccinia virus infection in an in vitro viral re-exposure

Abstract

The present study compares the profile of NK cells in an in vitro re-exposure by Vaccinia virus (VACV), in groups that have had a previous vaccination or natural infection. Our data suggests that stimulation with VACV triggers a cytotoxic response by NK cells marked by an increase of NCRs: NKp30, NKp44, and NKp46 in infected (vaccinated and unvaccinated) subjects and in non-infected vaccinated patients, when compared with non-infected unvaccinated individuals. However, the degranulation and secretion processes are inhibited in infected (vaccinated and unvaccinated) subjects and in the non-infected vaccinated patients, when compared with non-infected unvaccinated individuals. We demonstrated that stimulation with VACV downregulates the percentage of expression of Perforin, Granzyme A, and CD107a, but upregulate CD94 in infected (vaccinated and unvaccinated) subjects and in non-infected vaccinated patients, when compared with non-infected unvaccinated individuals. Furthermore, the percentage of IFN-γ(+) NK cells was significantly lower in non-infected unvaccinated subjects, when compared with infected (vaccinated and unvaccinated) and non-infected vaccinated individuals. Our results also show that the percentage of TNF-α(+) NK cells was significantly higher in infected (vaccinated and unvaccinated) subjects and in non-infected vaccinated patients, when compared with non-infected unvaccinated individuals, after in vitro stimulation with UV-inactivated VACV. Our data suggest that the expression of NCRs NKp30, NKp44, NKp46 and cytokines by NK cells are important in the innate response against VACV.

Weak vaccinia virus-induced NK cell regulation of CD4 T cells is associated with reduced NK cell differentiation and cytolytic activity

“…2H). A previous study with human NK cells from whole blood stimulated in vitro by UV-inactivated VACV showed that VACV-stimulated NK cells contained lower percentages of CD107a(+) cells than controls receiving media without inactivated VACV (Moreira-Silva et al, 2014). Although these data appear contradictory to our own observations with regard to the percentages of CD107a(+) NK cells, they still indicate that exposure to VACV causes a decrease in the percentage of NK cells bearing CD107a on their surface.…”

Natural Killer Receptor 1 Dampens the Development of Allergic Eosinophilic Airway Inflammation

“…The observed increase in the CCL22 in OVA immunized NCR1 gfp/gfp mice did not reach significance in comparison to OVA immunized NCR1 +/+ mice. Thus, there might be additional mediators that control the migration of lymphocytes to the site of inflammation following OVA immunization [65–68]. …”