Previous studies have shown increased aberrant expression of immune checkpoint (IC) proteins, such as programmed cell death receptor-1 (PD-1) and T cell immunoglobulin mucin-domain-containing-3 (Tim-3) on T cells from patients with multiple myeloma (MM), which result in T cell exhaustion and dysfunction. However, little is known about the mechanism regulating aberrant IC protein expression. In this study, we analyzed the expression of TOX (thymocyte selection-associated HMG BOX), a crucial transcription factor involved in T cell exhaustion, and its co-expression with PD-1, Tim-3, and CD244 in T cell subsets by multi-color fluorescent flow cytometry in peripheral blood (PB) and bone marrow (BM) samples from patients with MM. Significantly, the percentage of TOX + CD3 +/CD4 +/CD8 + T cells was increased, and similarly, higher numbers of TOX co-expression with PD-1, Tim-3, and CD244 on CD3 +/CD4 +/CD8 + T cells were found. Interestingly, the numbers of TOX +, TOX + PD-1 +, and TOX + Tim-3 + regulatory T (Treg) cells also significantly increased in both the PB and BM of MM patients. In summary, we for the first time observed increased TOX expression concurrent with PD-1, Tim-3, and CD244 on T cells, which may contribute to T cell exhaustion and impair their function in MM. Thus, TOX may be considered a potential target for reversing T cell exhaustion and improving T cell function in MM.

With the success of immune checkpoint inhibitors (ICI), such as anti- programmed death-1 (PD-1) antibody for solid tumors and lymphoma immunotherapy, a number of clinical trials with ICIs have been attempted for acute myeloid leukemia (AML) immunotherapy; however, limited clinical efficacy has been reported. This may be due to the heterogeneity of immune microenvironments and various degrees of T cell exhaustion in patients and may be involved in the IFN-γ pathway. In this study, we first characterized the percentage of PD-1+ and T cell immunoglobulin mucin-domain-containing-3 (Tim-3) +IFN-γ+ T cells in peripheral blood (PB) in AML compared with healthy individuals (HIs) by flow cytometry and further discussed the possibility of the reversal of T cell exhaustion to restore the secretion capacity of cytokines in T cells in AML based on blockade of PD-1 or Tim-3 (anti-PD-1 and anti-Tim-3 antibody) in vitro using a cytokine protein chip. A significantly increased percentage of PD-1+, Tim-3+, and PD-1+Tim-3+ IFN-γ+ T cells was observed in PB from patients with AML in comparison with HIs. Moreover, higher PD-1+IFN-γ+CD3+/CD8+ T cell levels were associated with poor overall survival in AML patients. Regarding leukemia cells, the percentage of Tim-3 in CD117+CD34+ AML cells was positively correlated with PD-1 in IFN-γ+CD4+ T cells. Furthermore, blocking PD-1 and Tim-3 may involve multiple cytokines and helper T cell subsets, mainly Th1 and Treg cells. Blockade of PD-1 or Tim-3 tends to restore cytokine secretion to a certain extent, a synergistic effect shown by the co-blockade of PD-1 and Tim-3. However, we also demonstrated the heterogeneity of secretory cytokines in ICI-treated T cells in AML patients.

Background: Natural killer (NK) cells are key effectors of innate immunity with broad-spectrum anti-tumor activity. However, peripheral blood-derived NK (PBNK) cells are typically quiescent, which limits their therapeutic utility. This study aimed to develop an efficient strategy for the in vitro activation and expansion of PBNK cells and then evaluate their potential anti-tumor efficacy in vitro and vivo. Methods: NK cells were isolated from healthy blood donors’ peripheral blood and stimulated with anti-CD16 and anti-CD137 antibodies in the presence of interleukin-2 (IL-2) and interleukin-15 (IL-15) under serum-free conditions, generating super NK (SNK) cells. The expression levels of activating and inhibitory receptors on the expanded SNK cells were assessed by flow cytometry. Cytotoxicity against tumor cells was assessed at various effector-to-target (E:T) ratios in vitro. In vivo, anti-tumor efficacy was evaluated in K562-engrafted NSG mice. RNA sequencing was performed to identify differentially expressed genes (DEGs) between SNK and PBNK cells. Results: Stimulation with anti-CD16 and anti-CD137 antibodies resulted in significant expansion of donor-derived NK cells, with over 861.9 ± 48.84-fold expansion (n = 5) within 15 days of culture. SNK cells exhibited significantly elevated expression of activating receptors, including NKG2D. Functionally, SNK cells demonstrated superior cytotoxicity compared with PBNK cells across all tested E:T ratios in vitro and higher expressions of the effector molecules interferon-gamma (IFN-γ) and granzyme B (Gzm B). In vivo, adoptive SNK cell transfer resulted in significant tumor suppression and prolonged survival in a dose-dependent manner. Transcriptomic analysis revealed significant enrichment of DEGs associated with cytokine and chemokine signaling, immune activation, and cytotoxic effector function compared with the PBNK cells. Conclusions: Anti-CD16/CD137 antibody stimulation, in combination with IL-2 and IL-15, facilitates robust activation and rapid expansion of functionally enhanced NK cells from peripheral blood. The resulting SNK cells demonstrated enhanced anti-tumor efficacy both in vitro and in vivo and may be used as allogeneic NK cell-based immunotherapy in future cancer treatment strategies.

Background: Studies investigating the association between single nucleotide polymorphisms (SNPs) of tumor necrosis factor-alpha (TNFα) and the efficacy of adalimumab (ADA) in ankylosing spondylitis (AS) therapy have reported conflicting results. We aimed to investigate the value of SNP typing of TNFα in predicting the efficacy of ADA in AS. Materials and methods: Eighty patients with active AS who received ADA treatment were followed up for 24 weeks. Six known SNPs of TNFα (+489G/A, -238G/A, -308G/A, -857C/T, -863C/A, and -1031C/T) were subjected to the SNaPshot SNP typing method, which has been proven to be a reliable, efficient, and cost-effective method for detecting SNPs. The relationship between each SNP genotype and the therapeutic efficacy of ADA was analyzed. Results: At the end of the 24-week follow-up, 58.8% of the patients with AS achieved Assessment of SpondyloArthritis International Society (ASAS) partial remission (PR), 67.5% of the patients achieved the criteria of an ASAS40 response (40% improvement on indices), and 53.8% of the patients achieved Ankylosing Spondylitis Disease Activity Score (ASDAS) major improvement (MI). The univariate analysis showed that patients with AS carrying the TNFα +489 A allele were more likely to achieve ASAS-PR, ASAS40 response criteria, and ASDAS-MI after ADA treatment. In the multivariate regression analysis, the TNFα +489 A allele was an independent factor influencing the efficacy of ADA in treating AS (ASAS-PR odds ratio (OR) = 2.66, 95% confidence interval (CI) = 1.01-7.01; ASAS40 OR = 4.56, 95% CI = 1.39-15.00; ASDAS-MI OR = 3.31, 95% CI = 1.02-10.69). Conclusions: The patients carrying the TNFα +489 A allele may be more likely to experience better therapeutic efficacy and achieve the treatment target (ASAS-PR, ASAS40 response, or ASDAS-MI) after receiving ADA treatment. Detection of TNFα +489 G/A may predict the therapeutic efficacy of ADA, which can be used in clinical practice to tailor treatment for individual patients with AS. Further studies with larger sample sizes and longer follow-up periods with imaging evaluation are needed to verify our findings.