A let-7 microRNA-RALB axis links the immune properties of iPSC-derived megakaryocytes with platelet producibility.

We recently achieved the first-in-human transfusion of induced pluripotent stem cell-derived platelets (iPSC-PLTs) as an alternative to standard transfusions, which are dependent on donors and therefore variable in supply. However, heterogeneity characterized by thrombopoiesis-biased or immune-biased megakaryocytes (MKs) continues to pose a bottleneck against the standardization of iPSC-PLT manufacturing. To address this problem, here we employ microRNA (miRNA) switch biotechnology to distinguish subpopulations of imMKCLs, the MK cell lines producing iPSC-PLTs. Upon miRNA switch-based screening, we find imMKCLs with lower let-7 activity exhibit an immune-skewed transcriptional signature. Notably, the low activity of let-7a-5p results in the upregulation of RAS like proto-oncogene B (RALB) expression, which is crucial for the lineage determination of immune-biased imMKCL subpopulations and leads to the activation of interferon-dependent signaling. The dysregulation of immune properties/subpopulations, along with the secretion of inflammatory cytokines, contributes to a decline in the quality of the whole imMKCL population.

Humanized mouse models with endogenously developed human natural killer cells for in vivo immunogenicity testing of HLA class I-edited iPSC-derived cells.

Human induced pluripotent stem cells (hiPSCs) genetically depleted of human leucocyte antigen (HLA) class I expression can bypass T cell alloimmunity and thus serve as a one-for-all source for cell therapies. However, these same therapies may elicit rejection by natural killer (NK) cells, since HLA class I molecules serve as inhibitory ligands of NK cells. Here, we focused on testing the capacity of endogenously developed human NK cells in humanized mice (hu-mice) using MTSRG and NSG-SGM3 strains to assay the tolerance of HLA-edited iPSC-derived cells. High NK cell reconstitution was achieved with the engraftment of cord blood-derived human hematopoietic stem cells (hHSCs) followed by the administration of human interleukin-15 (hIL-15) and IL-15 receptor alpha (hIL-15Rα). Such "hu-NK mice" rejected HLA class I-null hiPSC-derived hematopoietic progenitor cells (HPCs), megakaryocytes and T cells, but not HLA-A/B-knockout, HLA-C expressing HPCs. To our knowledge, this study is the first to recapitulate the potent endogenous NK cell response to non-tumor HLA class I-downregulated cells in vivo. Our hu-NK mouse models are suitable for the non-clinical evaluation of HLA-edited cells and will contribute to the development of universal off-the-shelf regenerative medicine.

Application of Aidi injection (艾迪注射液) in the bronchial artery infused neo-adjuvant chemotherapy for stage III A non-small cell lung cancer before surgical operation / 中国结合医学杂志

<p><b>OBJECTIVE</b>To study the effect of Aidi Injection (艾迪注射液,ADI) applied in the bronchial artery, applied in the bronchial artery infused (BAI) neo-adjuvant chemotherapy for stage III A non-small cell lung cancer (NSCLC) before surgical operation.</p><p><b>METHODS</b>The 60 patients with NSCLC stage III A underwent two courses BAI chemotherapy before tumor incision were assigned to two groups, the treatment and the control groups, using a random number table, 30 in each group. ADI (100 mL) was given to the patients in the treatment group by adding into 500 mL of 5% glucose injection for intravenous dripping once daily, starting from 3 days before each course of chemotherapy, and it lasted for 14 successive days, so a total of 28 days of administration was completed. The therapeutic effectiveness and the adverse reaction that occurred were observed, and the levels of T-lymphocyte subsets, natural killer cell activity, and interleukin-2 in peripheral blood were measured before and after the treatment.</p><p><b>RESULTS</b>The effective rate in the treatment group was higher than that in the control group (70.0% vs. 56.7%, P<0.05). Moreover, as compared with the control group, the adverse reaction that occurred in the treatment group was less and mild, especially in terms of bone marrow suppression and liver function damage (P<0.05). Cellular immune function was suppressed in NSCLC patients, but after treatment, it ameliorated significantly in the treatment group, showing significant difference as compared with that in the control group (P<0.05).</p><p><b>CONCLUSION</b>ADI was an ideal auxiliary drug for the patients in stage III A NSCLC received BAI neo-chemotherapy before surgical operation; it could enhance the effectiveness of chemotherapy, ameliorate the adverse reaction and elevate patients' cellular immune function; therefore, it is worthy for spreading in clinical practice.</p>