Bcelllike

Bcelllike is a descriptive term used in immunology and related fields to denote cells that resemble B lymphocytes in phenotype or gene expression, without necessarily being established B cells. It is not a formal cell type in the standard hematopoietic hierarchy, and its meaning can vary between studies.

Typical usage describes cells that express one or more B cell–associated markers, such as CD19, CD20 (MS4A1), CD79a/b, CD22, or surface immunoglobulin. Bcelllike cells may also show transcriptional programs associated with B cells, often involving factors like PAX5 and EBF1, and may exhibit partial or rearranged B cell receptor (BCR) features. However, they might lack the full differentiation or functional capabilities of canonical B cells, such as robust antibody production, which helps to distinguish them from true B cells.

Contexts in which the term appears include developmental and reprogramming studies, where non-B cells are induced to acquire B cell–like properties to study lineage plasticity, and cancer biology, where tumors or tumor-infiltrating cells display B cell–like immunophenotypes. In these settings, labeling as Bcelllike emphasizes shared markers or gene expression rather than identity as a conventional B cell.

Characterization typically relies on immunophenotyping by flow cytometry to detect surface markers, complemented by histology or immunohistochemistry. Transcriptomic analyses, including single-cell RNA sequencing, are used to assess B cell–specific gene programs, while BCR sequencing can determine the presence or absence of B cell receptor rearrangements.

See also: B cells, immunophenotyping, hematopoietic differentiation, B cell receptor.