Abstract

The tremendous clinical success of adoptive cell therapies indicates that specifically targeting the immune system could generate durable anti-tumor responses and lead to a high rate of complete remissions. Genetically engineering T cells to express a chimeric antigen receptor (CAR) to redirect and reprogram T cells has already paved the way for successful immunotherapies to fight against leukemia and lymphoma and is quickly expanding to treat many other malignant diseases, including solid tumors. Nevertheless, the biggest challenges are how to evaluate the quality of these re-engineered T cells and how to predict their in vivo behaviors once reinfused into a patient, including efficacy and potential side-effects. Moreover, there is a need to effectively characterize the antigen-specific response of these cell products for bioprocessing analysis and manufacturing optimization.

In this poster, we review single-cell polyfunctional profiling results obtained from several different sets of pre-infusion CAR-T samples, including anti-CD19 CAR-T samples from Novartis Pharmaceuticals [1] and Kite Pharma (Gilead) [2], GoCAR-T cell products from Bellicum Pharmaceuticals [3], and Bispecific CD19/22 CAR-T cells from the NIH [4]. In each case, CD4+ and CD8+ CAR-T cells were stimulated (details in [1], [2], and [3]) and subsequently analyzed at a single-cell level using IsoPlexis’ IsoCode chip. A 16-plex cytokine panel was used with samples in study [2], while samples in studies [1], [3], and [4] used a 32-plex cytokine panel.

Single-cell profiling revealed highly polyfunctional and heterogeneous responses across each patient cohorts [1] [2] [3] [4]. In study [2], an association was determined between the polyfunctional strength index (PSI) of the CAR-T products and the clinical outcome of the patients after receiving the treatment (p ≤ 0.0119). Similarly, a significant correlation was also identified between pre-infusion PSI and post-infusion