The inhibitory effect by hairy cell conditioned medium (HCCM) on the growth of granulocyte and erythrocyte colony forming cells was studied in vitro. The percent inhibition of CFU-C formation by HCCM from four hairy cell leukemia (HCL) patients ranged from 36% to 76%, while no inhibition was observed with conditioned medium (CM) obtained from three B-cell chronic lymphocytic leukemia (B-CLL) pa...

BACKGROUND Hairy cell leukemia is a rare form of leukemia and has been rarely reported in African and pediatric population. OBSERVATION We are reporting a 4-year-old child who was received for investigation for persistent anemia, prolonged fever, and thrombocytopenia. Bone marrow aspiration showed hypercellular marrow with cells characterized by irregular windblown-appearing cell borders with...

Monoclonal antibodies defining B-, T-, and myeloid-restricted cell surface antigens were used to characterize the lineage and state of differentiation of tumor cells isolated from 22 patients with hairy cell leukemia (HCL). These tumors were shown to be of B lineage because they strongly expressed the B cell-restricted antigens B1 and B4 and lacked T cell- and monocyte-restricted antigens. More...

Culture studies of peripheral blood mononuclear cells from 7 entirely typical cases of hairy cell leukemia showed that after culture in the presence of PHA for 2--5 days, the predominant cell type changed from E- SIg+ CIg+ gamma FcR+ muFcR+ hairy cells to an E+ SIg- CIg- gamma FcR-muFcR- population of transformed cells derived from hairy cells. Depletion and readdition experiments demonstrated ...

Surface IgG expression of 29 cases of hairy cell leukemia (HCL) was assessed using IgG-subclass-specific monoclonal and F(ab)'2 polyclonal antibodies. A marked preference for the IgG3 subclass was found, as 16 of 19 IgG-positive HCL's expressed IgG3. In 10 cases, IgG3 was concurrently expressed with other heavy chains. No preferential IgG3 expression was observed in 11 IgG-positive non-Hodgkin'...

Although the coexistence of hairy cell leukemia with sarcoidosis has been reported in a few cases in the literature, in our case the patient had been diagnosed and followed about 10 years with sarcoidosis and massive splenomegaly. It has been demonstrated that T helper 1 cells exist in organs influenced by sarcoidosis. These cells produce IL-2 and IFN-γ and induce a nonspecific inflammatory res...

Hairy cell leukaemia is a rare condition and the patient reported here is only the third such case out of 527 patients with all types of leukaemia seen at our hospital over the last 4 years. A second malignancy in a patient with hairy cell leukaemia has been documented in detail only once before (Adler, Shetty and Golomb, 1979). The association of Kaposi's sarcoma, a common tumour in parts of s...