Biphasic anti-osteoclastic action of intravenous alendronate therapy in multiple myeloma bone disease.

Multiple myeloma is a malignancy of plasma cells with osteolytic bone destruction. Bisphosphonates inhibit osteoclast activity and are widely used for the treatment of myeloma bone disease. We analyzed the changes in urinary cross-linked N-telopeptides of collagen (u-NTx) and urinary calcium (u-Ca) after bisphosphonate alendronate therapy in ten patients with myeloma bone disease. In all patients, the levels of u-Ca and u-NTx decreased within a week. After the maximum decrease of u-NTx, u-NTx started increasing in half of the patients. However, this further increase in u-NTx decreased again without any additional therapy. Disease severity and pretreatment u-NTx concentrations did not differ between patients with and without the rebound. Patients who did not have rebound had decreased bone marrow monocytes and decreased serum concentrations of interleukin 18, which is produced by monocytes. Our results suggest that impaired activity of monocytes, which are possible osteoclast precursors, is related to reduced bone destruction in multiple myeloma.

Increased serum interleukin-18 in a patient with systemic lupus erythematosus and T-cell large granular lymphocytic leukemia.

Interleukin-18 (IL-18) is a potent cofactor for T-helper (Th-1) cell development and inducer of cytotoxic T lymphocytes (CTL), and is reported to contribute to autoimmune diseases. T-cell large granular lymphocyte (T-LGL) leukemia involves the proliferation of autoreactive CTL that is often associated with autoimmune disorders. We found increased serum IL-18 concentrations in a 55-year-old woman with systemic lupus erythematosus (SLE) and T-LGL-leukemia. Her serum IL-18 concentrations correlated with the intensity of her SLE symptoms and the number of T-LGL cells in peripheral blood. This evidence suggests that IL-18 is involved in T-LGL-related autoimmune disorders.

Gamma interferon-induced nitric oxide production in mouse CD5+ B1-like cell line and its association with apoptotic cell death.

The in vitro effect of gamma interferon (IFN-gamma) on nitric oxide (NO) production in a mouse CD5+ B1-like cell line, TH2.52, was studied. The TH2.52 cell line is the hybridoma line between mouse B lymphoma line and mouse splenic B cells and expresses a series of B1 markers. IFN-gamma induced a marked NO production in TH2.52 cells through the expression of an inducible type of NO synthase (iNOS). IFN-gamma-induced NO production was triggered by the Janus tyrosine kinase (JAK)/signal transducer and activator of transcription (STAT) pathway since it was inhibited by AG490, a JAK2 inhibitor. The growth of TH2.52 cells significantly was inhibited in the presence of IFN-gamma. A significant number of cells underwent apoptotic cell death, accompanied by the DNA fragmentation, annexin V binding, and caspase 3 activation. N(G)-monomethyl-L-arginine, an iNOS inhibitor, prevented IFN-gamma-induced cell death. Therefore, IFN-gamma-induced NO production was possible in causing cell death in TH2.52 cells. Further, IFN-gamma-induced NO production and cell death significantly were prevented by interleukin-4, a representative Th2 cytokine. The immunological significance of IFN-gamma-induced NO production in a mouse B1-like cell line is discussed.

Interleukin 18 and hepatocyte growth factor in fulminant hepatic failure of adult onset Still's disease.

Adult onset Still's disease (AOSD) is a rheumatoid disorder characterized by polyarthritis, intermittent high fever, and salmon colored rashes. Liver dysfunction is usually mild and fulminant liver failure is rare. We describe a 20-year-old woman with AOSD and severe hepatic necrosis leading to hepatic failure requiring liver transplant. This severe liver disorder developed after decreases in fever, arthritis, and C-reactive protein. Interleukin 18 (IL-18), but not ferritin, increased in association with liver dysfunction. Hepatocyte growth factor (HGF) increased at the time of hepatic failure. IL-18 and HGF elevation may have contributed to this rare severe liver injury in AOSD.

Levels of vascular endothelial growth factor and hepatocyte growth factor in sera of patients with rheumatic diseases.

Abstract Angiogenesis plays an important role in the progression of rheumatic disease. We measured the levels of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) in sera from patients with rheumatic diseases and investigated whether these angiogenic factors would be useful in the evaluation of rheumatic diseases. Serum VEGF and HGF levels were determined using ELISA in 128 patients with rheumatic diseases and in 11 healthy controls. Serum VEGF and HGF levels were significantly higher in patients with rheumatic diseases compared to healthy controls [VEGF, 312 ± 20 pg/ml versus 61 ± 8 pg/ml (mean ± SE), P < 0.001; HGF, 935 ± 36 pg/ml versus 413 ± 49 pg/ml, P < 0.01]. Serum VEGF and HGF levels were significantly elevated in patients with adult Still's disease (VEGF, 1021 ± 258 pg/ml; HGF, 1500 ± 295 pg/ml) and were relatively increased in patients with active rheumatoid arthritis (RA) (VEGF, 359 ± 94 pg/ml) and systemic sclerosis (SSc) (VEGF, 356 ± 43 pg/ml; HGF, 1294 ± 224 pg/ml). HGF levels correlated with the clinical course and disease severity in rheumatic disease patients. VEGF levels correlated with the presence of Raynaud's phenomenon (P < 0.05), interstitial lung disease (ILD) (P < 0.05), and serum KL-6 levels (P < 0.01), whereas HGF levels correlated with cryoglobulinemia (P < 0.05), ILD (P < 0.05), serum C-reactive protein (CRP) (P < 0.05), thrombomodulin (P < 0.05), and KL-6 levels (P < 0.05) in rheumatic disease patients. VEGF levels correlated with the skin scores and KL-6 levels in SSc patients and also correlated with the disease activity of RA patients. These data suggest that serum VEGF and HGF levels are related to rheumatic disease activity and the presence of complications. Analysis of VEGF and HGF may be useful in the clinical evaluation of rheumatic disease patients.

Change of mouse CD5(+) B1 cells to a macrophage-like morphology induced by gamma interferon and inhibited by interleukin-4.

The in vitro effects of gamma interferon (IFN-gamma) on the mouse CD5(+) B1-cell line, TH2.52, a hybridoma between mouse B lymphoma and mouse splenic B cells that expresses a series of B1 markers, were investigated. A significant number of macrophage-like cells appeared in the cultures of TH2.52 cells exposed to IFN-gamma, these adhering to plastic dishes and exhibiting phagocytic activity. Positive for esterase staining, the macrophage-like cells returned to the original TH2.52 morphology upon removal of IFN-gamma. The change was prevented by treatment with SB202190, an inhibitor of p38 mitogen-activated protein (MAP) kinase and by transfection of a p38 MAP kinase dominant-negative mutant. Further, interleukin-4 (IL-4) inhibited IFN-gamma-induced phosphorylation of p38 MAP kinase and the appearance of macrophage-like cells. IFN-gamma and IL-4 exhibited contradictory actions on morphological change of CD5(+) B1 cells into macrophage-like cells. Differential regulation of CD5(+) B1 cells by IFN-gamma, a Th1 cytokine, and IL-4, a Th2 cytokine, may have clear immunological significance.

Clinical significance of vascular endothelial growth factor and hepatocyte growth factor in multiple myeloma.

Angiogenesis is a crucial process in the progression of multiple myeloma (MM). Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) are multifunctional cytokines that potently stimulate angiogenesis including tumour neovascularization. Serum levels of VEGF and HGF were measured in 52 patients with MM by enzyme-linked immunosorbent assay (ELISA). Serum levels of VEGF and HGF were elevated in MM patients compared with healthy controls (VEGF: mean 0.31 ng/ml and 0.08 ng/ml respectively, P < 0.01; HGF: mean 2.17 ng/ml and 0.45 ng/ml, respectively, P < 0.001). In serial samples taken after chemotherapy, serum VEGF and HGF levels were correlated with M-protein levels. Serum levels of VEGF were higher in patients with extramedullary plasmacytomas than in patients without them (P < 0.05). They were also significantly higher in a group of patients who showed poor response to chemotherapy (P < 0.01). Serum levels of HGF were higher in patients with complications such as anaemia, hypercalcaemia and amyloidosis than in patients without these complications (P < 0.01, P < 0.05, P < 0.05 respectively). Both serum VEGF and HGF levels were significant predictors of mortality (P = 0.01, P = 0.02, respectively, log-rank test). The present study demonstrated that serum levels of VEGF and HGF are significantly elevated and dependent on the severity of MM, suggesting that measurement of VEGF and HGF may be useful for assessing disease progression and for predicting the response to chemotherapy in MM patients.