123 results about "Megakaryocyte" patented technology

Methods for obtaining purified populations of megakaryocytes and platelets by ex vivo culture of stem cells are provided herein.

Human embryonic stem cells are induced to differentiate first into the hematopoietic lineage and then into megakaryocytes, the cells which generate platelets. The proper in vitro culture of megakaryocytes results in the production and shed of platelets. This makes possible, for the first time, the in vitro production of a human blood factor needed by many patients.

Methods and compositions for modulating interleukin-21 (IL-21)/IL-21 receptor (MU-1) activity using agonists or antagonists of IL-21 or IL-21 receptor (“IL-21R” or “MU-1”), are disclosed. IL-21/IL-21R antagonists can be used to induce immune suppression in vivo, e.g., for treating or preventing immune cell-associated pathologies (e.g., pathologies associated with aberrant activity of one or more of mature T cells (mature CD8+, mature CD4+ T cells), mature NK cells, B cells, macrophages and megakaryocytes, including transplant rejection and autoimmune disorders). IL-21/IL-21R agonists can be used by themselves or in combination with an antigen, e.g., as an adjuvant (e.g., a vaccine adjuvant), to up-regulate an immune response in vivo, e.g., for example, for use in treating cancer and infectious disorders.

Methods for obtaining purified populations of megakaryocytes and platelets by ex vivo culture of stem cells are provided herein.

A process for generating megacaryocyte by in vitro induction to umbilical blood cell CD34+ includes in vitro amplifying the CD34+ in the culture medium containing fetal calf serum, human SCF, human TPO and/or ligand flt-3 and inducing the generation of megacaryocytes in the non-serum culture medium containing human TPO, human interleukin 3(IL-3) and/or human GM-CSF. Its advantage is high inducing efficiency.

The present invention provides a method of generating megakaryocytes and platelets. In various embodiments, method involves the use of human embryonic stem cell derived hemangioblasts for differentiation into megakaryocytes and platelets under serum and stromal-free condition. In this system, hESCs are directed towards megakaryocytes through embryoid body formation and hemangioblast differentiation. Further provided is a method of treating a subject in need of platelet transfusion.

Provided is a megakaryocyte and/or platelet production method, enabling to produce a megakaryocyte and/or platelet from mesenchymal cells such as preadipocytes in a relatively short period of time, simply, in a large amount and at lower cost or more efficiently in vitro and a method for producing TPO simply and in a larger amount. A first invention is a method for producing a megakaryocyte and/or platelet, comprising culturing a mesenchymal cell in a mesenchymal cell culturing basic medium containing an iron ion and an iron transporter and collecting megakaryocytes and/or platelets from a culture. A second invention is a method for producing thrombopoietin, comprising culturing a mesenchymal cell or mesenchymal cell-derived megakaryocyte in a mesenchymal cell culturing basic medium containing an iron ion and an iron transporter and collecting thrombopoietin from a culture. A third invention is a method for producing thrombopoietin, comprising culturing a preadipocyte in a preadipocyte culturing basic medium containing dexamethasone, 3-isobutyl-1-methylxanthine and insulin and collecting thrombopoietin from a culture.

The present invention discloses a mouse anti-human CD41 monoclonal antibody hybridoma cell system, a monoclonal antibody and an immunohistochemical kit and an application thereof. A traditional hybridoma preparation technology is used to obtain hybridoma cell strain which excretes anti-human CD41 molecular monoclonal antibody stably. The excreted antibody can identify the conformational epitopes of the combination of human CD41 antigen and CD61 antigen and can inhibit the aggregation effect caused by ADP, collagen, HIP2, etc. The monoclonal antibody is marked biotin directly and combined with alkali phosphatase-strep avidin working fluid, substrate solution and fast red to form the immunohistochemical kit which uses SAP method to detect megakaryocyte. The kit and the detection method provided by the present invention can shorten the detection time and avoid repeated washing, so the status of cell chipping can not occur, the detection efficiency is improved greatly and the present invention is fit for common technicians to operate.

Human embryonic stem cells are induced to differentiate first into the hematopoietic lineage and then into megakaryocytes, the cells which generate platelets. The proper in vitroculture of megakaryocytes results in the production and shed of platelets. This makes possible, for the first time, the in vitro production of a human blood factor needed by many patients.

The invention discloses a process method for bone marrow smear digitization. The process method comprises the following steps: acquiring related information of bone marrow smears, generating global images, and performing digital labeling after obtaining the to-be-digitized area as well as karyocyte collecting quantity and megakaryocyte classifying quantity; feeding the bone marrow smears into scanning equipment for performing shooting scanning: a to-be-digitized area generated by low-power lens scanning, and labeling and recognizing object observers therein; generating a spliced image in the scanning area; switching to megakaryocyte in the megakaryocyte classifying quantity generated by high-power lens scanning, and labeling and recognizing the megakaryocyte; generating the scanned megakaryocyte image; switching to karyocyte in the karyocyte collecting quantity in the to-be-digitized area generated by oil lens scanning, labeling and recognizing the karyocyte; generating the scanned karyocyte image; and generating digitalized smears of physical bone marrow smears. The artificial microscopy process is simplified; the consistency and standardization of the bone marrow examination report results are improved; and remote consultation is conveniently carried out, and the turn-round time of the physical smears is reduced.

Methods are provided for obtaining expanded human cord blood cells expressing CD34. The methods involve seeding a sufficient amount of cord blood cells with a sufficient amount of menstrual cells under co-culture conditions suitable to promote expansion of the cord blood cells, and co-culturing the cord blood cells with the menstrual cells under culture conditions that support at least two or more population doublings of the cord blood cells. Methods are also provided for growing expanded human cord blood cells to give rise to any one of colony forming units, colony forming unit granulocyte macrophages (CFU-GM), burst forming unit erythroids (BFU-E), and colony forming unit granulocyte erythrocyte macrophage megakaryocyte (CFU-GEMM) blood lineage precursor cells. The expanded cells may express CD34, SSEA-4, and HLA-II. Compositions of the expanded cells are also provided.

Disclosed are methods and compositions for preventing and treating conditions associated with platelet aggregation, comprising administering a therapeutically effective amount of a composition that modifies the interaction of DNAJC10 with αIIbβ3 in a megakaryocyte, thereby altering the expression of αIIbβ3 on the surface of the megakaryocyte.