Anti-Hairy Cell Leukemia antibody [DBA.44]

Supplementary info

This supplementary information is collated from multiple sources and compiled automatically.

Activity summary

Hairy Cell Leukemia (HCL) is a rare type of chronic lymphocytic leukemia. It involves an abnormal proliferation of B lymphocytes which present with hair-like cytoplasmic projections. The disease is named for the hair-like cells that appear due to the presence of these projections. HCL is primarily found in the blood and bone marrow. These cells express a distinct immunophenotype with co-expression of CD11c CD25 CD103 and DBA.44 antigens making it recognizable through flow cytometry. HCL cells also carry a weight of approximately 60 kDa. The aberrant B cells infiltrate the bone marrow leading to fibrosis and subsequent pancytopenia.

Biological function summary

HCL affects the immune system by impairing normal B cell function. These abnormal cells fail to produce normal antibodies leading to weakened immune responses. The leukemia cells often accumulate in the spleen and liver causing organomegaly. Hairy cells interfere with hematopoiesis by occupying spaces in the bone marrow. Despite their abnormal nature they require support from the microenvironment for survival. HCL cells commonly exist as part of a complex with extracellular matrix proteins that help their adhesion and survival.

Pathways

HCL is tightly linked with the B-cell receptor (BCR) signaling pathway. The activation of BCR plays a significant role in the survival and proliferation of these malignant cells. HCL also involves the downstream pathway of the MAPK/ERK signaling cascade important for cell proliferation and survival. Proteins like spleen tyrosine kinase (SYK) are engaged actively in these pathways. The interaction between SYK and BCR signaling is essential for the pathogenesis of HCL as it promotes cell survival and proliferation.

Associated diseases and disorders

Hairy cell leukemia is linked closely to immunosuppression and increased susceptibility to infections. This is due to the ineffective immune response stemming from the dysfunctional B cells. Furthermore HCL is related to autoimmune disorders as the compromised immune surveillance can lead to autoantibody production. Clinically hairy cell leukemia is associated with the malfunction of proteins like BRAF where mutations in the BRAF gene particularly the V600E mutation are commonly observed in patients with HCL. This mutation provides targets for therapeutic interventions such as BRAF inhibitors which specifically aim to exploit the mutated pathways for treatment.