Figure 5.

DNR abrogates TGF-β signaling in NK cells

(A) Schematic depicting the effects of TGF-β binding to the receptor complex: UT NK cells express the wild-type TGF-βRII, which, when engaged with soluble TGF-β in the TME, initiates a signaling cascade that culminates in impaired NK cell phenotype and cytotoxicity. NK cells transduced with the DNR variant TGF-β receptors alter the intracellular signaling and allow for maintained or enhanced NK cell phenotype and cytotoxicity in the setting of tumor-associated TGF-β. Illustration created using Biorender.com. (B) CB NK cells can be genetically modified to co-express the B7H3 CAR and DNRII. (C) Representative flow analysis for B7H3 CAR and TGF-β RII expression on NK cells. (Right) Results for the transduction efficiency of CB-NK cells (n = 6). (D and E) Inhibition of SMAD2/3 phosphorylation by TGF-β in CB-NK cells expressing DNRII. (D) Representative flow analysis showing the pSMAD2/3 expression in UT-NK and transduced NK cells after exposure to exogenous TGF-β (red histogram) in comparison to non-treated NK cells (blue histogram). (E) Mean upregulation (%) of the pSMAD2/3 in NK cell products (n = 3) after culture in the presence (red bar) or absence (black bar) of TGF-β (2 ng/mL). The individual point represents the individual donor and error bars represent standard deviation. (∗p < 0.05, all comparisons.) The p values were generated by the Holm-Sidak multiple comparison test following two-way analysis of variance.