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CAR-T靶向治療實體瘤!

(2015-01-18 05:46:22) 下一個
編者按】12月(6-9)日在美國舊金山召開的第56屆美國血液學會年會(ASH)會議上,基因工程T細胞或者說嵌合抗原受體T細胞的研究再次成為代表們熱議的話題。因為臨床研究證明這種方法能有效治療白血病和淋巴瘤。這是一種利用基因改造技術表達腫瘤特異性嵌合抗原受體(Chimeric antigen receptor,CAR)的T細胞,研究顯示這種細胞具有獨特的靶向性、殺傷活性和持久性,是過繼性細胞免疫治療的最新解決方案;理論上,除了白血病和淋巴瘤,這一方法也能成為治療其他癌症的手段,前提是不能把生存需要的細胞全麵清除,這需要在腫瘤細胞特異抗原上有明確的認識。隻有這樣才能實現將癌細胞全部殺滅,同時保留正常細胞免於被殃及。如果能達到這樣的目的,這些研究的先驅們就會寫入癌症治療的曆史。

在2014.12.6,5:30 PM-7:30 PM;West Building, Level 1 (Moscone Center)的ASH會議中報道了CAR-T對實體瘤的治療研究初探,會議題目:“Engineered T Cell Receptor-Mimic Antibody, (TCRm) Chimeric Antigen Receptor (CAR) T Cells Against the Intracellular Protein Wilms Tumor-1 (WT1) for Treatment of Hematologic and Solid Cancers”

報道摘要:

目前表達腫瘤相關嵌合抗原受體的過繼T細胞療法(CAR-T)已在特定的白血病臨床應用中取得成功,因而尋找新的腫瘤(血液和惡性實體瘤)靶抗原就成為必須,然而目前大多數CARs僅針對特定類型的細胞表麵抗原。該實驗設計了第一個針對人胞內蛋白——WT1(腎母細胞瘤蛋白)的CAR-T,WT1在包括急慢性白血病和許多實體瘤中都過度表達。該CAR的T細胞受體是ESK1TCRm的單抗衍生物,稱為WT1 28z,在與RMFPNAPYL肽反應時高表達在HLA-A*02:01類細胞表麵。用Cr51試驗檢測其對各種腫瘤細胞係的細胞毒性,包括巨核細胞係SET2,急性髓細胞性白血病(AML)細胞係AML14,多發性骨髓瘤細胞係KARPAS,以及卵巢癌細胞係OVCAR3,並用非相關抗原的CAR-T作對照,試驗發現,WT1 28z CAR-T細胞對原發性AML骨髓細胞有細胞毒性,與非相關抗原的CAR-T相比,在和原代細胞或腫瘤細胞係共培養時,WT1 28z CAR-T可增強促炎症細胞因子的分泌,例如IFN-g, IL-2, GM-CSF。WT1 28z T細胞對於WT1-HLA-A*02:01來說是特異性的,並不對HLA-A*02:01和WT1雙陰的細胞係或初始細胞產生細胞毒性。目前正在用AML和卵巢癌的小鼠模型分別對WT1 28z T細胞和非相關抗原的CAR-T進行療效評估,其最終的目標是能夠讓這種新技術在血液瘤和實體瘤治療中得到應用。上述研究提示一個假設,即CAR-T或許也可以利用胞內抗原進行定向改造。

 


2155 Engineered T Cell Receptor-Mimic Antibody, (TCRm) Chimeric Antigen Receptor (CAR) T Cells Against the Intracellular Protein Wilms Tumor-1 (WT1) for Treatment of Hematologic and Solid Cancers

Sarwish Rafiq, PhD1*, Tao Dao, MD/PhD2*, Cheng Liu, PhD3*, David A. Scheinberg, MD, PhD4 and Renier J Brentjens, MD, PhD5

1Memorial Sloan-Kettering Cancer Center, New York, NY
2Sloan Kettering Institute, New York, NY
3Eureka Therapeutics, Emeryville, CA
4Chairman, Molecular Pharmacology and Chemistry, Memorial Sloan Kettering Cancer Center, New York, NY
5Leukemia Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY

 
Adoptive transfer therapy of T cells expressing chimeric antigen receptors (CAR) against tumor-associated antigens has been shown to be clinically successful in a limited set of leukemia.  However, novel antigen targets for both hematological and solid malignancies are required.  Most CARs described thus far are targeted against external antigens on particular cell types.  We have designed and engineered the first CAR T cell against a human intracellular protein, WT1.  WT1 is overexpressed in many cancers, including acute and chronic leukemias and numerous solid tumors.   Our TCRm CAR, derived from the ESK1 TCRm mAb, termed WT1 28z, is reactive with the RMFPNAPYL peptide of the WT1 protein that is processed and presented on the surface of cells in the context of HLA-A*02:01.   WT1 28z expressing T cells have high expression of the CAR on their surface.  They are cytotoxic in standard 51Cr assays against a range of cancer cell lines, including the megakaryoblastic cell line SET2, the acute myeloid leukemia (AML) cell line AML14, the multiple myeloma cell line KARPAS, and the ovarian cancer line, OVCAR3, as compared to CAR T cells against an irrelevant antigen. The WT1 28z CAR T cells are also cytotoxic against primary AML bone marrow blasts in this assay.  When co-cultured with these primary cells or cancer cell lines, the WT1 28z CAR T cells have enhanced production of proinflammatory cytokines such as IFN-g, IL-2, and GM-CSF, as compared to irrelevant CAR T cells.  Importantly, WT1 28z T cells are specific for the WT1-HLA-A*02:01 complex.  The cells do not show cytotoxicity against cell lines or primary cells that are not both HLA-A*02:01- positive and WT1 positive.  WT1 28z T cells are currently being tested alongside irrelevant antigen CAR T cells in AML and ovarian cancer murine models in vivo to assess efficacy, with the ultimate goal of translating this novel approach into the clinical setting for both hematological and solid cancers. The data provide the proof-of-concept that CAR T cells also may be directed at intracellular antigens.
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琬玥 回複 悄悄話 回複 'richard6000' 的評論 :
Hi Richard6000,

Last December i went to ASH meeting in San Francisco and got to know the scientific breakthrough of Car-T cell therapy in treating certain kinds of blood cancer:
Dr.Sadelain等人在ASH會議上報道指出,6名參加同一項試驗的淋巴瘤患者在接受該療法的治療後,腫瘤症狀均消失。而對於急性淋巴細胞性白血病(acute lymphoblastic leukaemia)這種更為嚴重的癌症而言,30名患者在經過治療後,有27人的症狀消失,而兩年後他們的血液中仍然存在有CAR T細胞.

Certain Clinical trials for solid tumors are ongoing in Memorial Sloan Kettering Cancer Center (MSKCC). Here is one of their links---
http://www.mskcc.org/blog/immunotherapy-shows-promise-treating-solid-tumors-chest
You can contact Dr. Michel Sadelain's team in MSKCC to find out if they have the other clinical trials.

GOD bless you and your families with the best luck

richard6000 回複 悄悄話 不太懂,對其他癌究竟前景如何,有無新的臨床試驗?
登錄後才可評論.