Protein / target
B-lymphocyte antigen CD19
Protein at a glance
Biological role
B cell proliferation involved in immune response
Primary system
Immune system
Strongest disease association
immunodeficiency, common variable, 3
Therapeutic maturity
Clinically validated target
Druggability
Antibody
Clinical development
9 approved · 5 in clinical development
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function
Functions as a coreceptor for the B-cell antigen receptor complex (BCR) on B-lymphocytes (PubMed:29523808). Decreases the threshold for activation of downstream signaling pathways and for triggering B-cell responses to antigens (PubMed:1373518, PubMed:16672701, PubMed:2463100). Activates signaling pathways that lead to the activation of phosphatidylinositol 3-kinase and the mobilization of intracellular Ca(2+) stores (PubMed:12387743, PubMed:16672701, PubMed:9317126, PubMed:9382888). Is not required for early steps during B cell differentiation in the blood marrow (PubMed:9317126). Required for normal differentiation of B-1 cells (By similarity). Required for normal B cell differentiation and proliferation in response to antigen challenges (PubMed:1373518, PubMed:2463100). Required for normal levels of serum immunoglobulins, and for production of high-affinity antibodies in response to antigen challenge (PubMed:12387743, PubMed:16672701, PubMed:9317126)
Subcellular location
Domains and Gene Ontology detail (17)Hide
Domains & features
Gene Ontology
- Cexternal side of plasma membrane
- Cextracellular exosome
- Cmembrane raft
- Cplasma membrane
- Cprotein-containing complex
- Pantigen receptor-mediated signaling pathway
- PB cell proliferation
- PB cell proliferation involved in immune response
- PB cell receptor signaling pathway
- PB-1 B cell differentiation
- Pimmunoglobulin mediated immune response
- Ppositive regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
View supporting evidenceHide supporting evidence
Immune signalling
- ·Functions as a coreceptor for the B-cell antigen receptor complex (BCR) on B-lymphocytes…
- ·antigen receptor-mediated signaling pathway
- ·B cell proliferation
- ·B cell proliferation involved in immune response
Kinase signalling
- ·positive regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction
View underlying pathways (6)Hide underlying pathways
Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Interaction neighbourhood
Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.
Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.
Drugs targeting this protein
Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.
B-lymphocyte antigen CD19 binding agent
Appears in clinical studies involving diffuse large B-cell lymphoma, follicular lymphoma, diffuse large B-cell lymphoma, diffuse large B-cell lymphoma
B-lymphocyte antigen CD19 binding agent
Appears in clinical studies involving diffuse large B-cell lymphoma, acute myeloid leukemia by FAB classification, B-cell chronic lymphocytic leukemia, diffuse large B-cell lymphoma
B-lymphocyte antigen CD19 cross-linking agent
Appears in clinical studies involving acute lymphoblastic leukemia, B-cell acute lymphoblastic leukemia, lymphoid leukemia, neoplasm
ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.
Translational evidence
Why this target matters therapeutically — disease associations, drugs in development, tractability and safety, from Open Targets.
Strongest genetic associations
Human genetic evidence — the most direct causal link between this target and a disease.
Highest-confidence therapeutic associations
Diseases where a drug acting on this target has already reached clinical development.
Highest overall evidence
Remaining associations by Open Targets' aggregated evidence score.
Show all associationsHide all associations
Open Targets ranks 1,271 associations for this target and we store the top 10 by aggregated score. The long tail is largely literature co-mention and RNA-expression evidence, not evidence that this target drives those diseases.
Known drugs · 14 total
diffuse large B-cell lymphoma · acute myeloid leukemia by FAB classification · B-cell chronic lymphocytic leukemia
neuromyelitis optica · neuromyelitis optica · myasthenia gravis
B-cell acute lymphoblastic leukemia · acute lymphoblastic leukemia · systemic lupus erythematosus
childhood leukemia · B-cell chronic lymphocytic leukemia · rheumatoid arthritis
diffuse large B-cell lymphoma · follicular lymphoma · diffuse large B-cell lymphoma
acute lymphoblastic leukemia · B-cell acute lymphoblastic leukemia · lymphoid leukemia
immunoglobulin G4-related sclerosing disease · autoimmune hemolytic anemia · systemic lupus erythematosus
diffuse large B-cell lymphoma · lymphoma · diffuse large B-cell lymphoma
mantle cell lymphoma · mantle cell lymphoma · hematopoietic and lymphoid cell neoplasm
bone marrow transplantation
Tractability
Clinical trials
Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.
Show remaining trials (24)Hide
ClinicalTrials.gov via the drug-target graph.
Forefront confidence
Our own weighting of the evidence behind each disease association. Human genetics and clinical evidence count for most; literature co-mention counts for little, because two entities sharing an abstract is not evidence that one drives the other.
The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the underlying per-type scores are shown above so the calculation can be checked.
What's happening now
Recent activity around this target, drawn from one canonical event stream. Every item is reached through 3 drugs that target this protein, so each event is news about that drug rather than about the protein directly.
- Research developmentStudy of Yescarta patients reveals genetic red flags for CAR-T therapy side effects
- New publicationA systematic review and meta-analysis of nonrelapse mortality after CAR T cell therapy.
- New publicationAxicabtagene Ciloleucel as Second-Line Therapy for Large B-Cell Lymphoma.
- New publicationCAR-HEMATOTOX: a model for CAR T-cell-related hematologic toxicity in relapsed/refractory large B-cell lymphoma.
- New publicationCurative outcomes following blinatumomab in adults with minimal residual disease B-cell precursor acute lymphoblastic leukemia.
- New publicationThe BiTE (bispecific T-cell engager) platform: Development and future potential of a targeted immuno-oncology therapy across tumor types.
- New publicationLong-term safety and activity of axicabtagene ciloleucel in refractory large B-cell lymphoma (ZUMA-1): a single-arm, multicentre, phase 1-2 trial.
- New publicationTisagenlecleucel in Adult Relapsed or Refractory Diffuse Large B-Cell Lymphoma.
- Regulatory approval
Approval: Kymriah (EMA)
- Regulatory approval
Approval: Yescarta (EMA)
- New publicationGrading of cytokine release syndrome associated with the CAR T cell therapy tisagenlecleucel.
- New publicationTisagenlecleucel in Children and Young Adults with B-Cell Lymphoblastic Leukemia.
Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.