Efficient cryopreservation technique preserves functionality and phenotype of highly purified human blood cell subsets. (144.21)

Abstract

Abstract During the course of infection with pathogens or exposure to immunogens, interactions between different cell subsets lead to efficient innate and/or adaptive immune responses. The availability of pure populations of different cell subsets allows observation of such interactions in vitro, and could provide essential clues to identify precise immune mechanisms such as cell to cell interactions during antigen presentation or CTL and T helper cell interactions. Such information would be valuable in designing strategies for cell therapy, for improved vaccines and for dampening autoimmune responses. We demonstrate that efficient cryopreservation techniques such as use of specialized freezing media, and initial controlled rate freezing followed by stringently monitored cryopreservation under the vapor phase of liquid nitrogen, allow highly purified frozen human blood cell subsets to retain their functional and differentiation capability. Indeed, cryopreserved CD4 and CD8 T cells show similar ability to proliferate and produce IFN-γ compared to fresh purified cell subsets derived from single or different PBMC donors. Other cell subsets such as CD3 cells and Monocytes also retain their functionality and differentiation capacity. Our results suggest that cryopreserved cell subsets can be used as a basic tool for studying cellular phenotype and function in longitudinal clinical studies.