Cryopreservation of lymphocytes allows samples to be stored for transport to laboratory sites, to be validated and/or standardized, or to be sent to multiple sites for assay development. This article, published in Vaccine, outlines the influence of cryopreservation on antigen-specific immunogenicity data gathered during a phase 2 malaria heterologous prime-boost vaccine trial. According to the findings analyzed, results indicated that testing cells after thaw can result in significant reduction of malaria antigen-specific interferon gamma-producing CD3+CD4+ effector cells, compared to cells tested fresh. These findings suggest that samples exposed to the least amount of processing possible are likely to provide the most comprehensive immunological insight, but further study could address remaining questions related to cryopreservation's effect on assay results.