BC-3 Cells

The BC-3 cell line is a human primary effusion lymphoma (PEL) model derived from the pleural effusion of an HIV-negative patient. It represents a rare subtype of B-cell non-Hodgkin lymphoma that typically presents as lymphomatous effusions in body cavities such as the pleura, pericardium, or peritoneum, often in the absence of detectable solid tumor masses. BC-3 is distinguished by its exclusive infection with Kaposi’s sarcoma-associated herpesvirus (KSHV or HHV-8) and complete absence of Epstein-Barr virus (EBV), a feature that sets it apart from most other PEL cell lines, which are typically dually infected.

Immunophenotypically, BC-3 cells express leukocyte common antigen (CD45) but lack classical B-cell (e.g., CD19, CD20, CD21, CD22) and T-cell (e.g., CD2, CD3, CD4, CD5, CD8) lineage markers, consistent with the undifferentiated immunophenotype of PEL. However, they do show variable expression of activation markers such as CD30, CD38, CD54, and HLA-DR. Genotypically, BC-3 exhibits clonal immunoglobulin gene rearrangements indicative of B-cell origin, but lacks c-myc oncogene rearrangements. Importantly, Southern blot and PCR analyses confirmed the presence of an intact ~170 kb KSHV genome, and electron microscopy demonstrated herpesvirus-like capsids, validating the line as a productive source of infectious KSHV particles.

BC-3 is included in the LL-100 panel of leukemia and lymphoma cell lines and clusters distinctly with other PEL models in transcriptomic analyses. It exhibits expression of PEL-characteristic genes such as PRDM1/BLIMP1, IL-10, SLAMF7, and members of the S100A family. These markers reflect a post-germinal center B-cell phenotype and underscore BC-3’s utility as a biologically relevant model for studying KSHV pathogenesis, PEL biology, and therapeutic strategies targeting KSHV-associated malignancies.