Challenges in the Development of NK-92 Cells as an Effective Universal Off-the-Shelf Cellular Therapeutic.

The human-derived NK-92 cell-based CAR-NK therapy exhibits inconsistency with overall suboptimal efficacy and rapid in vivo clearance of CAR-NK92 cells in cancer patients. Analysis indicates that although pre-existing IgM in healthy individuals (n = 10) strongly recognizes both NK-92 and CAR-NK92 cells, IgG and IgE do not. However, only a subset of cancer patients (3/8) exhibit strong IgM recognition of these cells, with some (2/8) showing pre-existing IgG recognition. These results suggest a natural immunoreactivity between NK-92 and CAR-NK92 cells and pre-existing human Abs. Furthermore, the therapy's immunogenicity is evidenced by enhanced IgG and IgM recognition postinfusion of CAR-NK92 cells. We also confirmed that healthy plasma's cytotoxicity toward these cells is reduced by complement inhibitors, suggesting that Abs may facilitate the rapid clearance of CAR-NK92 cells through complement-dependent cytotoxicity. Given that NK-92 cells lack known receptors for IgG and IgM, identifying and modifying the recognition targets for these Abs on NK-92 and CAR-NK92 cells may improve clinical outcomes. Moreover, we discovered that the 72nd amino acid of the NKG2D receptor on NK-92 cells is alanine. Previous studies have demonstrated polymorphism at the 72nd amino acid of the NKG2D on human NK cells, with NKG2D72Thr exhibiting a superior activation effect on NK cells compared with NKG2D72Ala. We confirmed this conclusion also applies to NK-92 cells by in vitro cytotoxicity experiments. Therefore, reducing the immunoreactivity and immunogenicity of CAR-NK92 and directly switching NK-92 bearing NKG2D72Ala to NKG2D72Thr represent pressing challenges in realizing NK-92 cells as qualified universal off-the-shelf cellular therapeutics.

A glycolysis-related signature to improve the current treatment and prognostic evaluation for breast cancer.

Background: As a heterogeneous malignancy, breast cancer (BRCA) shows high incidence and mortality. Discovering novel molecular markers and developing reliable prognostic models may improve the survival of BCRA. Methods: The RNA-seq data of BRCA patients were collected from the training set The Cancer Genome Atlas (TCGA)-BRCA and validation set GSE20685 in the Gene Expression Omnibus (GEO) databases. The "GSVA" R package was used to calculate the glycolysis score for each patient, based on which all the patients were divided into different glycolysis groups. The "limma" package was employed to perform differentially expression genes (DEGs) analysis. Key signature genes were selected by performing un/multivariate and least absolute shrinkage and selection operator (LASSO) C regression and used to develop a RiskScore model. The ESTIMATE and MCP-Counter algorithms were used for quantifying immune infiltration level. The functions of the genes were validated using Western blot, colony formation, transwell and wound-healing assay. Results: The glycolysis score and prognostic analysis showed that high glycolysis score was related to tumorigenesis pathway and a poor prognosis in BRCA as overactive glycolysis inhibited the normal functions of immune cells. Subsequently, we screened five key prognostic genes using the LASSO Cox regression analysis and used them to establish a RiskScore with a high classification efficiency. Based on the results of the RiskScore, it was found that patients in the high-risk group had significantly unfavorable immune infiltration and prognostic outcomes. A nomogram integrating the RiskScore could well predict the prognosis for BRCA patients. Knockdown of PSCA suppressed cell proliferation, invasion and migration of BRCA cells. Conclusion: This study developed a glycolysis-related signature with five genes to distinguish between high-risk and low-risk BRCA patients. A nomogram developed on the basis of the RiskScore was reliable to predict BRCA survival. Our model provided clinical guidance for the treatment of BRCA patients.

In Vitro Nanobody Library Construction by Using Gene Designated-Region Pan-Editing Technology.

Camelid single-domain antibody fragments (nanobodies) are an emerging force in therapeutic biopharmaceuticals and clinical diagnostic reagents in recent years. Nearly all nanobodies available to date have been obtained by animal immunization, a bottleneck restricting the large-scale application of nanobodies. In this study, we developed three kinds of gene designated-region pan-editing (GDP) technologies to introduce multiple mutations in complementarity-determining regions (CDRs) of nanobodies in vitro. Including the integration of G-quadruplex fragments in CDRs, which induces the spontaneous multiple mutations in CDRs; however, these mutant sequences are highly similar, resulting in a lack of sequences diversity in the CDRs. We also used CDR-targeting traditional gRNA-guided base-editors, which effectively diversify the CDRs. And most importantly, we developed the self-assembling gRNAs, which are generated by reprogrammed tracrRNA hijacking of endogenous mRNAs as crRNAs. Using base-editors guided by self-assembling gRNAs, we can realize the iteratively diversify the CDRs. And we believe the last GDP technology is highly promising in immunization-free nanobody library construction, and the full development of this novel nanobody discovery platform can realize the synthetic evolution of nanobodies in vitro.