Role of NF- kappaB binding sites in the regulation of inducible nitric oxide synthase by tyrosine kinase

In macrophages, lipopolysaccharide (LPS) alone or in combination with interferon- gamma (IFN- gamma) has been shown to release a nitric oxide (NO) through the increase of the transcription of the inducible nitric oxide synthase (iNOS) gene. To investigate the exact intracellular signaling pathway of the regulation of iNOS gene transcription by LPS plus IFN- gamma, the effects of protein tyrosine kinase (PTK) inhibitor and protein kinase C (PKC) inhibitors on NO production, iNOS mRNA expression, nuclear factor- kappaB (NF- kappaB) binding activity and the promoter activity of iNOS gene containing two NF- kappaB sites have been examined in a mouse macrophage RAW 264.7 cells. LPS or IFN- gamma, stimulated NO production, and their effect was enhanced synergistically by mixture of LPS and IFN- gamma. The PTK inhibitor such as tyrphostin reduced LPS plus IFN- gamma-induced NO production, iNOS mRNA expression and NF- kappaB binding activity. In contrast, PKC inhibitors such as H-7, Ro-318220 and staurosporine did not show any effect on them. In addition, transfection of RAW 264.7 cells with iNOS promoter linked to a CAT reporter gene revealed that tyrphostin inhibited the iNOS promoter activity through the NF- kappaB binding site, whereas PKC inhibitors did not. Taken together, these suggest that PTK, but not PKC pathway, is involved in the regulation of the iNOS gene transcription through the NF- kappaB sites of iNOS promoter in RAW 264.7 macrophages by LPS plus IFN- gamma.

A Case of Invasive Pulmonary Aspergillosis Cured with Liposomal Amphotericin, Granulocyte Transfusion and Surgery in an Allogeneic Hemopoietic Stem Cell Transplantation Recipient / 대한혈액학회지

The prognosis of invasive aspergillosis in allogeneic bone marrow transplantation recipients is grave in the absence of bone marrow recovery in spite of antifungal treatment with amphotericin B. Beneficial role of granulocyte transfusion in neutropenic patients with fungal infection has been re-evaluated since granulocyte colony-stimulating factor made effective collection of granulocyte possible. And Liposomal amphotericin appears to be an effective alternative to conventional amphotericin B with much less toxicity. A 34-year-old patient with acute lymphoblastic leukemia developed invasive pulmonary aspergillosis during very early period of allogeneic hemopoietic stem cell transplantation. We treated the case successfully with liposomal amphotericin and granulocyte transfusion and surgery in spite of known high mortality of invasive aspergillosis in transplantation patients.