An In-Vitro Study of the Expansion and Transcriptomics of CD⁴⁺ and CD⁸⁺ Naïve and Memory T Cells Stimulated by IL-2,...

The growth of T cells ex vivo for the purpose of T cell therapies is a rate-limiting step in the overall process for cancer patients to achieve remission. Growing T cells is a fiscally-, time-, and resource-intensive process. Cytokines have been shown to accelerate the growth of T cells, specifically IL-2, IL-7, and IL-15. Here a design of experiments was conducted to optimize the growth rate of different naïve and memory T cell subsets using combinations of cytokines. Mathematical models were developed to study the impact of IL-2, IL-7, and IL-15 on the growth of T cells. The results show that CD⁴⁺ and CD⁸⁺ naïve T cells grew effectively using moderate IL-2 and IL-7 in combination, and IL-7, respectively. CD⁴⁺ and CD⁸⁺ memory cells favored moderate IL-2 and IL-15 in combination and moderate IL-7 and IL-15 in combination, respectively. A statistically significant interaction was observed between IL-2 and IL-7 in the growth data of CD⁴⁺ naïve T cells, while the interaction between IL-7 and IL-15 was found for CD⁸⁺ naïve T cells. The important genes and related signaling pathways and metabolic reactions were identified from the RNA sequencing data for each of the four subsets stimulated by each of the three cytokines. This systematic investigation lays the groundwork for studying other T cell subsets.