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Genetic engineering of allogeneic cell therapeutics that fully prevents rejection by a recipient’s immune system would abolish the requirement for immunosuppressive drugs or encapsulation and support large-scale manufacturing of off-the-shelf cell products. Previously, we generated mouse and human hypoimmune pluripotent (HIP) stem cells by depleting HLA class I and II molecules and overexpressing CD47 (B2M−/−CIITA−/−CD47+). To determine whether this strategy is successful in non-human primates, we engineered rhesus macaque HIP cells and transplanted them intramuscularly into four allogeneic rhesus macaques. The HIP cells survived unrestricted for 16 weeks in fully immunocompetent allogeneic recipients and differentiated into several lineages, whereas allogeneic wild-type cells were vigorously rejected. We also differentiated human HIP cells into endocrinologically active pancreatic islet cells and showed that they survived in immunocompetent, allogeneic diabetic humanized mice for 4 weeks and ameliorated diabetes. HIP-edited primary rhesus macaque islets survived for 40 weeks in an allogeneic rhesus macaque recipient without immunosuppression, whereas unedited islets were quickly rejected.

In this work, we present a study of the propagation of low-frequency magneto-acoustic waves into the solar chromosphere within small-scale inclined magnetic fields over a quiet-magnetic network region utilizing near-simultaneous photospheric and chromospheric Dopplergrams obtained from the HMI instrument onboard SDO spacecraft and the Multi-Application Solar Telescope (MAST) operational at the Udaipur Solar Observatory, respectively. Acoustic waves are stochastically excited inside the convection zone of the Sun and intermittently interact with the background magnetic fields resulting into episodic signals. In order to detect these episodic signals, we apply the wavelet transform technique to the photospheric and chromospheric velocity oscillations in magnetic network regions. The wavelet power spectrum over photospheric and chromospheric velocity signals show a one-to-one correspondence between the presence of power in the 2.5-4 mHz band. Further, we notice that power in the 2.5-4 mHz band is not consistently present in the chromospheric wavelet power spectrum despite its presence in the photospheric wavelet power spectrum. This indicates that leakage of photospheric oscillations (2.5-4 mHz band) into the higher atmosphere is not a continuous process. The average phase and coherence spectra estimated from these photospheric and chromospheric velocity oscillations illustrate the propagation of photospheric oscillations (2.5-4 mHz) into the solar chromosphere along the inclined magnetic fields. Additionally, chromospheric power maps estimated from the MAST Dopplergrams also show the presence of high-frequency acoustic halos around relatively high magnetic concentrations, depicting the refraction of high-frequency fast mode waves around vA ~ vs layer in the solar atmosphere., 16 pages, 7 figures, Accepted for Publication in Journal of Atmospheric and Solar-Terrestrial Physics (Special Issue of STP-15)

Transplantation of allogeneic pancreatic donor islets has successfully been performed in selected patients with difficult-to-control insulin-dependent diabetes and impaired awareness of hypoglycemia (IAH). However, the required systemic immunosuppression associated with this procedure prevents this cell replacement therapy from more widespread adoption in larger patient populations. We report the editing of primary human islet cells to the hypoimmune HLA class I– and class II–negative and CD47-overexpressing phenotype and their reaggregation into human HIP pseudoislets (p-islets). Human HIP p-islets were shown to survive, engraft, and ameliorate diabetes in immunocompetent, allogeneic, diabetic humanized mice. HIP p-islet cells were further shown to avoid autoimmune killing in autologous, diabetic humanized autoimmune mice. The survival and endocrine function of HIP p-islet cells were not impaired by contamination of unedited or partially edited cells within the p-islets. HIP p-islet cells were eliminated quickly and reliably in this model using a CD47-targeting antibody, thus providing a safety strategy in case HIP cells exert toxicity in a future clinical setting. Transplantation of human HIP p-islets for which no immunosuppression is required has the potential to lead to wider adoption of this therapy and help more diabetes patients with IAH and history of severe hypoglycemic events to achieve insulin independence.

The objective of the present research investigation was to protect Bombax ceiba by revealing their endophytic fungi diversity for disease management. In the present research investigation, a total of 64 fungal endophytes were purified and, Aspergillus tamari was identified as a core fungal endophyte. The fungus showed the highest average linear growth rate of 6.2 mm/day and isolation frequency at 80% on tomato dextrose agar with white or dark brown or black or purple-brown to yellowish-green color variations with mycelial growth in between 65 mm to 90 mm on the media and 8 to 31 numbers of spores/ microscopic field. Further, the fungus revealed 2.86 g/100g of total wet biomass and 0.25 g/100g of the dried biomass of corn bran with 5.30 g/100ml of the aqueous crude extract in solid-state fermentation. Mycochemical screening of the crude extract showed alkaloids, terpenoids, steroids, tannins, saponins, flavonoids, phenols with 29.0060±0.03223 mg of total phenolic and 12.2549±0.02345 mg of flavonoids content. Thin layer chromatography was used to get purified potent spots of alkaloids [0.29], flavonoids [0.41] terpenoids [0.15] and saponins [0.91]. The fungus produced chitinase, amylase, protease, and cellulases enzyme. Further the aqueous crude extract worked as an agent of antioxidant in the FRAP at the rate of 1.2407±0.00702 while PM at 0.7983±0.00351, antimicrobials against E. coli (100mg/ml at the rate of 16.3±0.57) and Aspergillus niger (100mg/ml at the rate of 20.5 ± 0.24), and in anthelmintic activity, extract induced paralysis in earthworms within 3 minutes and death in 8 minutes. It is concluded that the Bombax ceiba has the potential to purify the potent fungal endophytes and their bioactive compounds that may be helpful to evaluate in vivo models against different diseases.

Off-the-shelf CAR T cells potentially offer advantages over autologous strategies such as ease of manufacturing, quality control, off-the-shelf availability, and lack of T cell dysfunction, as well as the ability to generate a more consistent CAR T product from healthy T cells. However, the vigorous host-versus-graft immune response against histoincompatible T cells prevents expansion and persistence of allogeneic CAR T cells and mitigates the efficacy of this approach. A major challenge is that, while HLA deletion can result in adaptive immune evasion, innate reactivity is enhanced with this approach. CD47 overexpression can block both NK cell and macrophage killing (J Exp Med 2021;218(3):e20200839), and we hypothesized that T cells would lose their immunogenicity when human leukocyte antigen (HLA) class I and II genes are disrupted and CD47 is over-expressed. We describe here the engineering of human immune evasive CAR T cells building on our previously described hypoimmune technology (Nat Biotechnol 2019;37(3):252-258 and Proc Natl Acad Sci U S A 2021;118(28):e2022091118).Human T cells from healthy donors were obtained by leukapheresis. CRISPR/Cas12b technology was used to disrupt the B2M, CIITA, and TCR genes, and lentiviral transduction was used to overexpress CD47 and to express a CD19 CAR to generate hypoimmune (HIP) CD19 CAR T cells. Control T cells were unmanipulated except for overexpression of the CD19 CAR (unmodified).For 3 months persistence studies, allogeneic SGM3 humanized mice were injected with 1 × 106 Luc+ Nalm6 cells and received 7 × 106 control CD19 CAR T cells or HIP CD19 CAR T cells.In the mice treated with either unmodified CD19 CAR T cells and HIP CD19 CAR T cells, tumor control was initially rapidly achieved. However, unmodified CD19 CAR T cells were eventually rejected by the host and the loss of these cells resulted in re-growth of tumor. By contrast, in HIP CD19 CAR T injected mice, tumor control was maintained throughout the study, including following a rechallenge at day 83 with NALM6 cells without further administration of HIP CD19 CAR T cell. Flow cytometry at endpoint from bone marrow and spleen confirmed persistence of HIP CD19 CAR T cells.These findings show that HIP CD19 CAR T cells are immune evasive in allogeneic recipients and data suggest that HIP CD19 CAR T cells are able to persist and maintain efficacy without immunosuppression. Citation Format: Xiaomeng Hu, Pascal Beauchesne, Karl Manner, Corie Gattis, Priscilla Ngo, Rowena De Jesus, Ramya Ankala, Chi Young, Frank Wells, Lindong Weng, Kathy White, William E. Dowdle, Aaron Foster, Terry J. Fry, Sonja Schrepfer. Engineered hypoimmune CAR T cells provide lasting tumor control in immunocompetent allogeneic humanized mice even with re-challenge. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4091.