Research Support, Non-U.S. Gov't Journal Article 1N3CZ14C5O 9007-49-2 B cell B cells Class Ia Phosphatidylinositol 3-Kinase DNA EC 2.7.1.- EC 2.7.1.137 EC 3.1.3.48 Epitopes, B-Lymphocyte Fluorescent Dyes Germinal Center (GC) reaction Hematopoietic stem cell transplantation Hyper-IgM syndrome Immunoglobulin M Immunological ontogeny Kappa-deleting recombination excision circles; Letter Leukocyte Common Antigens Lymphocyte development Multicenter Study Newborn screening; PIK3R1 PIK3R1 protein, human RNA Splice Sites Rhodamine 123 Severe combined immunodeficiency T cell receptor excision circles;