阅读说明：本技术 激活素受体iia型变体及其使用方法 (Activin receptor type IIA variants and methods of use thereof ) 是由 J·S·西拉 J·拉基 于 2019-05-09 设计创作，主要内容包括：本发明的特征在于包含细胞外ActRIIA变体的多肽。在一些实施方案中,本发明的多肽包含与Fc结构域单体或部分融合的细胞外ActRIIA变体。本发明的特征还在于使用所述多肽治疗涉及低红血细胞水平的疾病或病况(例如,贫血或失血；纤维化；或肺高压)药物组合物和方法。(The invention features polypeptides that include an extracellular ActRIIA variant. In some embodiments, the polypeptides of the invention comprise an extracellular ActRIIA variant fused to an Fc domain monomer or moiety. The invention also features pharmaceutical compositions and methods of using the polypeptides to treat diseases or conditions involving low red blood cell levels (e.g., anemia or blood loss; fibrosis; or pulmonary hypertension).)