The effect of human recombinant interferon alpha 2 (IFN alpha 2) on hairy cells obtained from 16 patients was evaluated. All patients promptly responded to induction of remission with 2 X 10(6) U/m2 interferon alpha 2 b, three times a week, sc. In order to achieve a more detailed insight into the mode of action of interferon in this disease, we determined the influence of IFN alpha 2 on the incorporation of radiolabeled thymidine and uridine into hairy cells. While both 3H-thymidine and 3H-uridine incorporation were unaffected by IFN alpha 2 in a 3-hour incubation period, a significant increase in uridine incorporation into hairy cells, but not CLL cells, was observed after 24 h. Cell surface marker analysis performed with monoclonal antibodies did not reveal a quantitative alteration of the immunophenotype of hairy cells in vitro. In addition, natural killer cells, assessed by monoclonal antibodies and a cytotoxicity assay against K 562 cells, were found to be decreased in 9 out of 10 patients prior to therapy. Although IFN alpha 2 could stimulate natural killer cells in vivo, we did not find a consistent correlation between the activation of these cells and the response to therapy. We conclude, therefore, that NK cells play no major role in the regression of hairy cells. Furthermore, IFN alpha 2 does not alter antigenic determinants in vitro, but leads to an enhanced incorporation of 3H-uridine into hairy cells in vitro, thus indicating a possible role for the induction of RNA synthesis in vivo.

Adult↗

PubMed1987

Effect of alpha 2-interferon on hairy cells and cell lines: a role for type I interferon receptors and RNA synthesis.

The binding of alpha 2-interferon to highly purified plasma membrane proteins of malignant human lymphoid cells was assessed by Western Blotting. The human hairy cell leukemia cell line JOK-1 revealed three major alpha-interferon binding proteins with molecular weights of 120, 100, and 32 kD. Pretreatment of JOK-1 cells with alpha-interferon in vitro results in a disappearance of these proteins, which is in concordance with receptor down-regulation on JOK-1 cells. In a case of T chronic lymphocytic leukemic (CLL), a differential binding pattern of two proteins with 100 and 85 kD was observed, whereas a case of B-CLL did not yield any signal detection. In addition, mononuclear cells from patients with hairy cell leukemia and CLL were found to differ with respect to the in vitro incorporation of nucleic acid precursors. alpha 2-Interferon enhances [3H] uridine incorporation into hairy cells, whereas this phenomenon can be detected in CLL cells only to a much lesser extent.

DNA, Neoplasm↗

PubMed1987

Management of primary herpes in pregnancy complicated by ruptured membranes and extreme prematurity: case report.

A case of primary herpes simplex vaginitis during pregnancy became complicated by rupture of membranes at 25.5 weeks' gestation. The patient was treated with intravenous acyclovir shortly after rupture, and managed expectantly. Genital lesions rapidly abated, and the infant was delivered by cesarean section at 26.5 weeks' gestation after labor ensued. Transplacental passage of acyclovir was documented. The infant then was treated with a ten-day course of intravenous acyclovir. The infant has remained culture negative for 12 months after delivery.

Acyclovir↗