has plasma membrane part develops from has low plasma membrane amount precursor B cell early pro-B cell late pro-B cell 2010-04-28T12:06:06Z The late pro-B cell, also referred to as Hardy fraction C, is a late-stage progenitor cell in the progression of B cell development in the bone marrow. B cells are an essential part of humoral immunity, the component of the immune system that produces antibodies against pathogens. The pro-B cell developmental stage occurs in the bone marrow and is divided into early pro-B cell and late pro-B cell stages: first, early pro-B cells rearrange the short D (diversity) and J (joining) segments of the H-chain and become late pro-B cell, in which a second rearrangement combines an upstream selected V gene segment with the short DJ region. Successful in-frame rearrangement in the late pro-B cell leads to expression of Igμ and its assembly with the surrogate light chain and Igα and Igβ to form the pre-B cell receptor in large pre-B cells. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) A pre-B cell precursor is CD19-low, CD22-positive , CD34-positive, CD38-positive. https://cellxgene.cziscience.com/cellguide/CL_0002048 Late pro-B cells are also reportedly CD10-positive, CD20-negative, CD21-negative, and TdT-positive. Transcription factors: PU.1-positive, Ikaros-positive, E2A-positive, and PAX5-positive. CD19 molecule CD34 molecule B-cell receptor CD22 ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 1