{"entity":{"id":"fcrh5","kind":"target","name":"FcRH5 (FCRL5)","aka":["FcRH5","FCRH5","IRTA2","CD307e","Fc receptor-like 5"],"tldr":"FcRH5 is a surface protein found almost only on B cells and myeloma plasma cells, which makes it a target for T-cell engaging antibodies in multiple myeloma.","summary":"FCRL5 encodes Fc receptor-like 5, a B-lineage surface receptor expressed on mature B cells and retained on plasma cells; on myeloma cells expression is near-universal and higher than on normal counterparts, in part through 1q21 gain where the gene sits. Cevostamab, a FcRH5 x CD3 bispecific antibody, is in late-stage trials for relapsed and refractory multiple myeloma; no approval names the antigen yet.","asOf":"2026-09-23","wikipedia":"https://en.wikipedia.org/wiki/FCRL5","links":[{"label":"HGNC HGNC:18508","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:18508"},{"label":"UniProt Q96RD9","url":"https://www.uniprot.org/uniprotkb/Q96RD9/entry"}],"tags":["biomarker-parent","surface-antigen"],"related":["fcrh5-expression"],"cancers":["multiple-myeloma","myeloma-relapsed-refractory"],"sections":[],"technologies":[],"targets":[],"drugs":["cevostamab"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"symbol":"FCRL5","role":[],"sources":[],"specificity":"lineage-antigen","distribution":"one-type","specificityNote":"Lineage antigen shared with normal lymphoid tissue cells: HPA blood lineage lineage enriched at or above 25 nTPM, and 1 antibody (Cevostamab) aim at it, so normal cells of the lineage are hit too. HPA FCRL5: RNA tissue enriched (lymphoid tissue 34 nTPM); blood lineage lineage enriched (B-cells 14 nTPM); no normal tissue stained high. Distribution: 1 cancer family in the corpus carries a prevalence row, label threshold or catalogue link for it (Multiple myeloma); Open Targets associates it with 0 specific cancer types at or above 0.5. (Rule 5 of scripts/fetch-target-specificity.ts.)","specificitySources":[{"label":"Human Protein Atlas FCRL5 tissue","url":"https://www.proteinatlas.org/ENSG00000143297-FCRL5/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Human Protein Atlas FCRL5 pathology","url":"https://www.proteinatlas.org/ENSG00000143297-FCRL5/pathology","note":"patients per staining level per cancer type (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000143297 associations","url":"https://platform.opentargets.org/target/ENSG00000143297/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:18508","ensembl":"ENSG00000143297","uniprot":"Q96RD9","entrez":"83416","firstDescribed":2001,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Nakayama et al, Biochem. Biophys. Res. Commun, 2001, \"BXMAS1 identifies a cluster of homologous genes differentially expressed in B cells\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/11453668/","biology":"A type I transmembrane protein with immunoglobulin-like domains that modulates B-cell receptor signalling; its restricted lineage expression, like BCMA and GPRC5D, is what makes it a T-cell redirection target.","whereFound":["Multiple myeloma (near-universal on plasma cells)","B-cell lymphomas and chronic lymphocytic leukaemia"],"targetClass":"surface-antigen","prevalence":[]},"route":"/targets/fcrh5/","neighbours":{"biomarker":[{"id":"fcrh5-expression","kind":"biomarker","name":"FcRH5 expression","route":"/biomarkers/fcrh5-expression/"}],"cancer":[{"id":"multiple-myeloma","kind":"cancer","name":"Multiple myeloma","route":"/cancers/multiple-myeloma/"},{"id":"myeloma-relapsed-refractory","kind":"cancer","name":"Relapsed or refractory multiple myeloma","route":"/cancers/myeloma-relapsed-refractory/"}],"drug":[{"id":"cevostamab","kind":"drug","name":"Cevostamab","route":"/drugs/cevostamab/"}]}}