CD94

引言 在人类免疫缺陷病毒（human immunodeficiency virus，HIV）感染中，CD8+T细胞对于病毒的清除至关重要【1】。因此，CD8+T细胞生物学动态与HIV感染患者息息相关。在慢性感染和肿瘤中，持续的抗原刺激诱导耗竭性T细胞（exhausted T cell，Tx）的产生【2】。TX的典型特征是由TOX等转录因子驱动的转录组和表观组重塑介导的效应功能减弱和抑制性受体的高表达【2】。值得注意的是，TOX不仅表达于Tx，也会表达于部分多功能效应记忆性T细胞，有时甚至与TCF-1共表达【3,4】，呈现干细胞样特性。研究表明，在大多数HIV感染患者中，HIV-特异性CD8+T细胞耗竭分子表达增加与高病毒载量和疾病进展相关【3,5】。在HIV感染患者外周血中，部分HIV-特异性CD8+T细胞中检测到TCF-1和TOX共表达【4】。作为HIV病毒存在和复制的主要位点，淋巴结内CD8+T细胞的表型和功能状态对于治疗策略的改善和设计至关重要。 近日，美国埃默里大学国家灵长动物研究中心微生物与免疫学部Mirko Paiardini研究团队在Nature Immunology杂志发表了题为Distinct SIV-specific CD8+ T cells in the lymph node exhibit simultaneous effector and stem-like profiles and are associated with limited SIV persistence的研究文章。这项研究通过流式、质谱、scRNA-seq和TCR-seq等分析在淋巴结内鉴定一群具有干细胞特性中间效应功能的SIV-特异性TOXhiTCF1+CD39+CD8+T细胞，该细胞倾向于淋巴滤泡定居并与靶细胞靠近，且能分化为终末效应细胞参与SIV病毒控制，为SIV/HIV感染提供新的免疫治疗靶点。 作者首先在恒河猴中建立猴免疫缺陷病毒（simian immunodefciency virus，SIVmac239）早期（42天）和晚期（17个月）感染模型。流式分析表明淋巴结CD8+T细胞内TOX表达随SIV感染时间延长而显著增加，尤其在CD95+记忆性CD8T细胞（memory CD8+T，TM）。与此同时，流式分析进一步发现淋巴结内 TOX+CD8+TM呈现GzmB+TCF-1-CD39+PD-1+TIGIT+TIM3+CD101+（传统效应T细胞，effector T, TEFF）和GzmK+GzmBlowTCF-1highCD39+PD-1+TIGIT+TIM3+CD101+两种。在未感染恒河猴中，淋巴结CD8+TM主要是TCF1+CD39-（占87%），而TCF1+CD39+只占6%；而在SIV早期感染淋巴结CD8+TM中，TCF1+CD39-占60%，TCF1+CD39+增加至27%；在晚期感染中，TCF1+CD39-降低至30%，而TCF1-CD39+TEFF占30%，TCF1+CD39+增加至40%。尽管TCF1+CD39+细胞群低表达细胞毒GzmB分子，但其与传统TCF1-CD39+TEFF细胞群有相似地活化脱颗粒能力。总之，这些数据表明SIV感染促进淋巴结CD8+T细胞TCF1-CD39+和TCF1+CD39+两种细胞群中TOX表达，虽然TCF1+CD39+细胞低表达细胞毒分子，但表现中间效应功能。 为了深入探究TCF1+CD39+CD8+TM功能，作者分离SIV感染恒河猴淋巴结内TCF1+CD39-、TCF1+CD39+和TCF1-CD39+CD8+TM并行质谱分析。结果证实TCF1+CD39+低表达细胞毒分子，包括perforin、GzmB和GzmA。此外，TCF1+CD39+细胞群高表达CD62L（T细胞迁移和淋巴结驻留相关）、CRTAM（淋巴结驻留）、DAP10、EOMES和IFNAR2（抗病毒相关）、NKG2C、NKG2D、CD94、CD160和GzmM（NK细胞毒相关以及T细胞增殖、扩增和功能相关）、CCL5（限制HIV感染）、ZHX3和PLK1（促增殖）和Bcl6（维持CD8细胞干性）。随后，作者分离早期SIV感染淋巴结中SIV特异性CD8+TM并行scRNA-seq分析，发现细胞分为C1（效应）、C2（干细胞样）、C3（增殖）、C4（IFN）和C5（其他）群。值得注意的是，TCF1+CD39+主要富集在C2群，表明干细胞样特性。TCR-seq分析指出TCF1+CD39+细胞群TCR克隆扩增，且主要克隆型与C1群重叠，表明TCF1+CD39+细胞群与TEFF存在线性关系。研究报道PD-1阻断促进干细胞样CD8+T细胞增殖和向TEFF分化【6】。作者发现PD-1抑制剂确实显著增加TCF1+CD39+CD8+TM和TCF1-CD39+TEFF比例，但Ki-67的增加仅在TCF1+CD39+CD8+TM细胞。这些结果表明TCF1+CD39+CD8+TM是一种有干细胞特性的中间效应细胞群，且具有向TEFF分化的能力。 随后，作者在SIV感染恒河猴中发现TCF1+CD39+CD8+TM的比例与血浆病毒载量以及淋巴结SIV DNA库呈负相关，表明其可以控制病毒和疾病进展。考虑到CD8+T细胞归巢至淋巴结滤泡与低病毒载量有关【7-9】，作者检测TCF+CD39+CD8+T细胞向淋巴结滤泡的迁移能力。首先，相比于TCF-CD8+T细胞，TCF-CD39+和TCF+CD39+CD8+T细胞CXCR5（滤泡归巢受体）表达显著增加，且TCF1+CD39+CD8+TM中CXCR5的表达同样与血浆病毒载量以及淋巴结SIV DNA库呈负相关，表明CXCR5对于TCF1+CD39+CD8+TM抗SIV的重要作用。其次，免疫荧光证实相比于TCF-CD8+T细胞，更多的TCF1+CD39+CD8+TM定位于B淋巴滤泡区，且与病毒RNA+CD4+靶细胞距离更近，表明TCF1+CD39+CD8+TM细胞具有更好的能力与感染CD4+靶细胞相遇以控制病毒。最后，作者在人HIV淋巴结样本中同样检测到TCF1+CD39+CD8+T细胞的存在。虽然低表达GzmB，但抗原刺激同样诱导脱颗粒和IFNγ表达，表明人HIV感染中TCF1+CD39+CD8+TM细胞可能具有类似的抗病毒能力。 综上所述，这项研究在猴和人缺陷免疫病毒感染淋巴结中鉴定一群具有干细胞样中间效应功能的TCF1+CD39+CD8+T细胞群，该细胞尽管缺乏经典细胞毒分子表达，但可以通过CXCR5定位于淋巴结滤泡区并与病毒感染CD4+T细胞作用，并继续分化为终末效应T细胞控制病毒载量，为促进TCF1+CD39+CD8+T扩增介导的病毒控制免疫治疗提供理论基础。 参考文献 1. David R, Collins., Gaurav D, Gaiha., Bruce D, Walker.(2020). CD8+ T cells in HIV control, cure and prevention. Nat Rev Immunol, 20(8), 0. doi:10.1038/s41577-020-0274-9 2. Christian U, Blank., W Nicholas, Haining., Werner, Held., Patrick G, Hogan., Axel, Kallies., Enrico, Lugli., et al. (2019). Defining 'T cell exhaustion'. Nat Rev Immunol, 19(11), 0. doi:10.1038/s41577-019-0221-9 3. Jean-Christophe, Beltra., Sasikanth, Manne., Mohamed S, Abdel-Hakeem., Makoto, Kurachi., et al. (2020). Developmental Relationships of Four Exhausted CD8+ T Cell Subsets Reveals Underlying Transcriptional and Epigenetic Landscape Control Mechanisms. Immunity, 52(5), 0. doi:10.1016/j.immuni.2020.04.014 4. Takuya, Sekine., André, Perez-Potti., Son, Nguyen., Jean-Baptiste, Gorin., Vincent H, Wu., Emma, et al. (2020). TOX is expressed by exhausted and polyfunctional human effector memory CD8+ T cells. Sci Immunol, 5(49), 0. doi:10.1126/sciimmunol.aba7918 5. David R, Collins., Jonathan M, Urbach., Zachary J, Racenet., Umar, Arshad., Karen A, Power., et al. (2021). Functional impairment of HIV-specific CD8+ T cells precedes aborted spontaneous control of viremia. Immunity, 54(10), 0. doi:10.1016/j.immuni.2021.08.007 6. Se Jin, Im., Masao, Hashimoto., Michael Y, Gerner., Junghwa, Lee., Haydn T, Kissick., Matheus C, et al. (2016). Defining CD8+ T cells that provide the proliferative burst after PD-1 therapy. Nature, 537(7620), 0. doi:10.1038/nature19330 7. Morgan A, Reuter., Perla M, Del Rio Estrada., Marcus, Buggert., Constantinos, Petrovas., Sara, et al. (2017). HIV-Specific CD8(+) T Cells Exhibit Reduced and Differentially Regulated Cytolytic Activity in Lymphoid Tissue. Cell Rep, 21(12), 0. doi:10.1016/j.celrep.2017.11.075 8. Son, Nguyen., Claire, Deleage., Samuel, Darko., Amy, Ransier., Duc P, Truong., Divyansh, Agarwal., et al. (2019). Elite control of HIV is associated with distinct functional and transcriptional signatures in lymphoid tissue CD8(+) T cells. Sci Transl Med, 11(523), 0. doi:10.1126/scitranslmed.aax4077 9. Constantinos, Petrovas., Sara, Ferrando-Martinez., Michael Y, Gerner., Joseph P, Casazza., Amarendra, et al. (2017). Follicular CD8 T cells accumulate in HIV infection and can kill infected cells in vitro via bispecific antibodies. Sci Transl Med, 9(373), 0. doi:10.1126/scitranslmed.aag2285 https://doi.org/10.1038/s41590-024-01875-0 责编|探索君 排版|探索君 来源|BioArt End 往期精选 围观 一文读透细胞死亡(Cell Death) | 24年Cell重磅综述（长文收藏版） 热文 Cell | 是什么决定了细胞的大小？ 热文 Nature | 2024年值得关注的七项技术 热文 Nature | 自身免疫性疾病能被治愈吗？科学家们终于看到了希望 热文 CRISPR技术进化史 | 24年Cell综述

Clinical-stage CAR-T company enrolling patients for Phase 1 trial to evaluate SynKIR™-310, a new treatment for relapsed/refractory B-cell Non-Hodgkin Lymphomas PHILADELPHIA, Oct. 8, 2024 /PRNewswire/ -- Verismo Therapeutics, a clinical-stage CAR-T company developing novel KIR-CAR platform technology, today announced that it has activated its CELESTIAL-301 Phase 1 clinical trial at Sarah Cannon Research Institute (SCRI) at Colorado Blood Cancer Institute (CBCI). CBCI offers clinical trials through SCRI, one of the world's leading oncology research organizations conducting community-based clinical trials. CBCI is the largest and most experienced full-service blood and marrow transplant program in Colorado and among the top programs in the country, making it an ideal location for this clinical trial. CELESTIAL-301 will assess safety, tolerability, and preliminary efficacy of SynKIR™-310 in patients with relapsed/refractory (r/r) B-cell Non-Hodgkin Lymphomas (B-cell NHL), including Diffuse Large B Cell lymphoma (DLBCL), Follicular Lymphoma (FL), Mantle Cell Lymphoma (MCL), and Marginal Zone Lymphoma (MZL). The Phase 1 multicenter clinical trial will enroll patients who previously received CAR T therapy but who have since relapsed or become refractory to it as well as patients who never received CAR T therapy. CELESTIAL-301 trial seeks to address several areas of high unmet medical need. Commercially approved CAR T cell therapies have shown impressive high initial response rates in blood cancers. Over time, however, these therapies result in relapse in an estimated 40-50% of patients1. Such relapses are in part due to lack of long-term T cell effector function and persistence. There are currently very limited treatment options for patients with r/r DLBCL who relapse following treatment with commercial CAR T cell therapies. Ongoing clinical investigations into new and/or salvage therapies for these patients have not yet addressed the unmet medical need. SynKIR™-310 relies on Verismo's unique KIR-CAR platform and proprietary CD19 binder (DS191). SynKIR™-310 is directed by DS191 to target a similar epitope of CD19 as the commercially approved CAR T therapies, with the added potential to prolong the anti-tumor T cell function and persistence. This could potentially improve KIR-CAR T Cell persistence and prevent early disease relapse in patients with aggressive lymphomas. "This trial embodies Verismo's continued commitment to combatting advanced cancers and addressing high areas of unmet medical need," said Dr. Laura Johnson, CSO of Verismo Therapeutics. "SynKIR™-310 has significant potential to help patients with B-cell Non-Hodgkin Lymphomas and be especially beneficial for patients that relapsed after previous infusions of CAR T cell therapies." Verismo achieved IND clearance from the FDA in May 2024 to proceed with this multicenter clinical trial investigating SynKIR™-310. SynKIR™-310 is Verismo's second clinical pipeline following SynKIR™-110, which targets aggressive mesothelin-expressing solid tumors. For more information about the CELESTIAL-101 clinical trial, please visit ClinicalTrials.gov: NCT06544265. About the KIR-CAR Platform The KIR-CAR platform is a multi-chain CAR T cell therapy and has been shown in preclinical animal models to be capable of maintaining antitumor T cell activity even in challenging tumor microenvironments. Using NK cell derived KIR and DAP12 split signaling provides a novel combined activation and co-stimulation separate from the usual T cell stimulation pathways. It also enables sustained chimeric receptor expression and improves KIR-CAR T cell long term function. This results in prolonged T cell functional persistence and leads to regression of solid tumors and blood cancers in preclinical models that are resistant to traditional CAR T cell therapies. The KIR-CAR platform is being investigated in combination with many additional emerging technologies to potentially provide the next-generation multimodal targeted immunotherapy for patients in need. About Verismo Therapeutics Verismo Therapeutics is a pioneer in multi-chain KIR-CAR technology, with its first two assets SynKIR™-110 and SynKIR™-310 currently in Phase 1 clinical trials. Verismo is the only company developing the KIR-CAR platform, using a modified NK cell derived receptor and DAP12 pairing in T cells, designed to improve persistence and efficacy against aggressive tumors. The KIR-CAR platform technology was developed specifically for treating advanced solid tumors and B-cell cancers and malignancies, areas of high unmet medical need. For more information, visit: 1Blood Adv (2020) 4 (22): 5607-5615 ; Biol Blood Marrow Transplant (2019) 25(11): e344-e351 https:doi.org/10.1016/j.bbmt.2019.06.036; Front Pediatr (2024) 11. Media Contact : Pavel Aprelev | [email protected] SOURCE Verismo Therapeutics WANT YOUR COMPANY'S NEWS FEATURED ON PRNEWSWIRE.COM? 440k+ Newsrooms & Influencers 9k+ Digital Media Outlets 270k+ Journalists Opted In GET STARTED

SAN FRANCISCO, CALIFORNIA, Sept. 24, 2024 (GLOBE NEWSWIRE) -- GT Biopharma, Inc. (the “Company”) (NASDAQ: GTBP), a clinical stage immuno-oncology company focused on developing innovative therapeutics based on the Company's proprietary natural killer (NK) cell engager TriKE® platform, today announced it will host a virtual KOL event on Thursday, October 10, 2024 at 12:00 PM ET. To register, click here. The event will feature Jeffrey Miller, MD1 and Mark Juckett, MD from the University of Minnesota Medical School2, who will give an overview of the NK cell therapy landscape, discuss current limitations and provide perspective on the future direction of the field as it expands into exciting new therapeutic areas beyond oncology including inflammatory autoimmune indications. Dr. Miller will elaborate on GT Biopharma’s TriKE® platform which has created an extensive pipeline of NK cell engagers. He will define where these engagers may best fit into the broader therapeutic landscape. Dr. Juckett will speak to GT Biopharma’s Phase 1 trial expected to start in Q4 evaluating GTB-3650 monotherapy for the treatment of acute myeloid leukemia (AML). A live question and answer session will follow the formal presentation. Dr. Miller is the Consulting Senior Medical Director at GT Biopharma and holds stock and options in GTBP.The University of Minnesota, pursuant to its license agreement with GT Biopharma, is entitled to receive royalties should commercial sales of GTB-3650 be realized. This interest has been reviewed and managed by the University of Minnesota in accordance with its conflict of interest policies. About Jeffrey Miller, MD Dr. Miller has been interested in NK cell biology, NK cell development, the acquisition of NK cell receptors and seamless translation into clinical trials throughout his entire academic career. Currently, the lab is focused on mechanisms which determine the enhanced function seen with CMV induced adaptive NK cells, facilitating immune synapses with IL-15 containing Trispecific Killer Engagers (TriKEs), IL-15 biology, NK cell killer immunoglobulin receptor (KIR) acquisition and function (NK cell education), and developing NK cell therapeutics. Throughout his career at the University of Minnesota, he has mentored faculty and delivered hundreds of NK cells products to patients with cancer. His team has identified unique NKC2C+ NK cell repertoires exhibit a methylation signature of CD8+ T cells with properties of immune memory. Adaptive NK cells are distinctly different from canonical NK cells and signal through CD16 using a dominant CD3-zeta signal by downregulation of Fc-gamma R1. Adaptive NK cells are better primed for killing, cytokine production, ADCC and exhibit unique metabolic signatures that enhance their survival. He has developed state-of-the-art functional readouts to study NK cells from the laboratory and the clinic based on high resolution testing. He was the first to report that haploidentical allogeneic human NK cells can persist and expand for up to one month after adoptive transfer. Based on these studies a significant part of his effort is trying to understand how to exploit NK cells for therapeutic purposes against infection and cancer and how to improve outcomes from allogeneic hematopoietic cell transplantation. Clinically, he has developed first-in-human trials using allogeneic donor NK cells, rhIL-15, IL-15/IL-15R alpha-Fc (ALT-803, now called N-803), an NK cell TriKE that engages NK cells and AML targets that costimulates NK cells with an IL-15 linker. Dr. Miller's experience and translational expertise has supported a transition from individual related donor NK cell products to induced pluripotent stem cell (iPSC) derived NK cells. Advantages of using this off-the-shelf platform include the flexibility of multiple gene edits, immediate cryopreserved product availability, multi-doing strategies and combinatorial therapy with targeted agents to enhance NK cell function. Dr. Miller is devoted to team science and mentoring. He has supervised > 400 NK cell products and sponsored >10 INDs and his team has studied >4000 transplant patients. Dr. Miller's experience, NIH grants and translational expertise provides a rich environment for training. About Mark Juckett, MD Dr. Juckett is Professor of Medicine in the Division of Hematology, Oncology, and Transplantation at the University of Minnesota. His practice is committed to caring for people with blood cancers, especially when bone marrow transplantation or cellular therapy is required. In an era where the treatment options are expanding rapidly for patients with acute leukemia, myeloid diseases, and other blood cancers, Dr. Juckett believes the best care is determined after considering a patient and family's preferences and values. The Bone Marrow Transplant and Cell Therapy Program at the University of Minnesota strives to provide the best medical care possible through the innovative investigation into new and better treatment options and by incorporating discoveries into our daily medical care. His interest in helping people with blood cancers includes efforts to improve recovery through guided survivorship. The treatment of blood cancers can be a long and challenging journey for some people, who may be cured, but not recovered after treatment is complete. Dr. Juckett is also interested in developing survivorship care that will give patients and families the tools and support needed to regain a long, happy, and healthy life. About GT Biopharma, Inc. GT Biopharma, Inc. is a clinical stage biopharmaceutical company focused on the development and commercialization of immuno-oncology therapeutic products based on our proprietary TriKE® NK cell engager platform. Our TriKE® platform is designed to harness and enhance the cancer killing abilities of a patient’s immune system’s natural killer cells. GT Biopharma has an exclusive worldwide license agreement with the University of Minnesota to further develop and commercialize therapies using TriKE® technology. For more information, please visit gtbiopharma.com. Forward-Looking Statements Certain statements in this press release may constitute "forward-looking statements" regarding future events and our future results. All statements other than statements of historical facts are statements that could be deemed to be forward-looking statements. These statements are based on current expectations, estimates, forecasts, and projections about the markets in which we operate and the beliefs and assumptions of our management. Words such as "expects," "anticipates," "targets," "goals," "projects", "intends," "plans," "believes," "seeks," "estimates," "endeavors," "strives," "may," or variations of such words, and similar expressions are intended to identify such forward-looking statements. Readers are cautioned that these forward-looking statements are subject to a number of risks, uncertainties and assumptions that are difficult to predict, estimate or verify. Therefore, actual results may differ materially and adversely from those expressed in any forward-looking statements. Such risks and uncertainties include those factors described in our most recent annual report on Form 10-K, as such may be amended or supplemented by subsequent quarterly reports on Form 10-Q, or other reports filed with the Securities and Exchange Commission. Readers are cautioned not to place undue reliance on these forward-looking statements. The forward-looking statements are made only as of the date hereof, and we undertake no obligation to publicly release the result of any revisions to these forward-looking statements. For more information, please refer to our filings with the Securities and Exchange Commission. TriKE® is a registered trademark owned by GT Biopharma, Inc. Investor Relations Contact: LifeSci AdvisorsCorey Davis, Ph.D.cdavis@lifesciadvisors.com212-915-2577