Study of cord blood natural killer cell suppressor activity.

We tested the immunosuppressive effect of cord blood (CB) natural killer (NK) cells using highly purified CB NK cells in mixed lymphocyte cultures (MLC) containing autologous CB T cells as responders. Control cultures were done without NK cells. Our findings revealed that CB NK cells induced a dose-dependent inhibition of T lymphocyte proliferation as evidenced by decreased 3H-thymidine incorporation in MLC. The T cell alloproliferation was significantly decreased in the presence of an NK cell to responder cell ratio of 0.1, 0.2 or 0.4 compared with control cultures done without NK cells (p=0.02, 0.003 and 0.0002, respectively). T lymphocyte inhibition was also achieved using irradiated CB NK cells and still demonstrable on addition of disparate CB NK and T cells to the MLC. In agreement with previous reports, adult blood NK cells inhibited the alloreactive T cells in the MLC using adult T lymphocytes as responders. Compared to control cultures done without NK cells, statistically significant inhibition of 3H-thymidine incorporation in MLC was observed at a ratio of NK cells to responder cells ratio of 0.2 or 0.4 (p=0.02). To investigate the mechanism whereby CB NK cells can interfere with the development of alloreactive T cells in MLC, we measured the tumour necrosis factor-alpha (TNF-alpha) concentrations in MLC supernatants using NK cell-depleted or unseparated CB mononuclear cells (MNC) as responders. The results revealed significantly high levels of TNF-alpha in the absence of NK cells (p=0.007). We conclude that CB NK cells suppress alloreactive T lymphocytes as do their counterparts in adult blood. However, the high NK to T cell ratio in CB could contribute to a more marked suppressive potential compared to that in adult blood. The mechanism of NK-mediated inhibition is likely related to disruption of the TNF-alpha pathway of T-lymphocyte activation.

Are basic fibroblast growth factor and vascular endothelial growth factor prognostic indicators in pediatric patients with malignant solid tumors?

Angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Among angiogenic factors, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) appear to be useful markers in adults with cancer. The aim of this pilot study was to determine the levels of VEGF in serum and bFGF in serum and urine of children with solid tumor at diagnosis (as measured by ELISA), and to investigate whether these parameters provide prognostic information. Forty consecutive patients with different types of cancer were prospectively included in this study. Median values of all studied angiogenic factors were higher in patients than in controls (n = 40), and the differences were statistically significant for bFGF in serum and urine: 10 versus 3 pg/ml (P = 0.0004) and 6406 versus 0 pg/g of creatinine (P < 0.0001), respectively. Among patients, median serum values of bFGF and VEGF were higher in children with metastatic disease (n = 14) than in those with localized disease (n = 26). The difference was statistically significant for serum bFGF: 17.5 versus 6 pg/ml (P = 0.02). Serum angiogenic factor levels correlated with outcome. The estimated event-free survival at 3 years was 79% for patients with normal bFGF values (n = 13) versus 42% (n = 26; P = 0.02) for those with high levels, and 71% in case of normal VEGF values (n = 20) versus 38% (n = 19; P = 0.04) for those with high levels. No benefit of normal urinary bFGF values was observed. Our results provide a rationale for exploring the clinical interest of bFGF and VEGF measurements in body fluids of a larger group of children with cancer.

Cytokines and vascular cell adhesion molecule-1 in the blood of patients undergoing HPC mobilization.

BACKGROUND: The mechanism of HPC mobilization in humans is unclear. In this study, the relationship between PBPC mobilization and blood levels of G-CSF, endogenous cytokines (IL-8, SCF, thrombopoietin [TPO]), and the vascular cell adhesion molecule-1 (VCAM-1) was analyzed in patients with malignancy who were undergoing a PBPC mobilization regimen. STUDY DESIGN AND METHODS: Fifty-four patients with multiple myeloma (MM) and 29 with breast cancer (BC) underwent a mobilization regimen combining conventional chemotherapy and G-CSF up to the last day of PBPC collection. The CD34+ cell count was determined on each day when leukapheresis was scheduled. Venous blood samples (n = 117) were drawn before apheresis for CD34+ cell count (flow cytometry) and cytokine (G-CSF, IL-8, SCF, TPO) and VCAM-1 measurements (ELISA). RESULTS: In multiple regression analysis, SCF was a significant determinant of CD34+ cell levels in BC patients (R = 0.50, p = 0.03) and of VCAM-1 levels in MM patients (R = 0.32, p = 0.02). SCF was negatively correlated with CD34+ cell count in patients with BC. SCF and VCAM-1 blood levels were correlated in MM and BC patients. CONCLUSION: SCF and VCAM-1 could play a role in PBPC mobilization in patients and could be useful measures by which to study patients undergoing a mobilization regimen.

[Importance of bFGF ("basic fibroblast growth factor") for diagnosis and treatment of hemangiomas]. / Intérêt du dosage du bFGF ("basic Fibroblast Growth Factor") pour le diagnostic et le traitement des hémangiomes.

OBJECTIVES: Hemangiomas of infancy follow a characteristic three-phases course: proliferation, involution, regressed Proliferative endothelial cells predominate during the proliferative phase. Moreover it has been shown that patients with active angiogenesis have elevated levels of urinary bFGF (basic Fibroblast Growth Factor). PATIENTS AND METHODS: Here we report our preliminary results of urinary bFGF assay (ELISA) for the diagnosis and follow up of severe hemangioma. We also assayed bFGF in normal infants, in patients with large vascular malformations and in infants with Kasabach-Merritt syndrome. RESULTS: In the control group, urinary bFGF was elevated in new borns but nul or very low in infants. Urinary bFGF levels were normal, i.e. very low in 4 patients with a vascular malformation. In infants with a clinically proliferative hemangioma, urinary bFGF was elevated in 8 among the 10 studied. bFGF levels guided treatment in 9 patients. Urinary bFGF was elevated in 4 patients with Kasabach-Merritt syndrome. DISCUSSION: Angiogenesis is regulated by angiogenic and inhibitory factors. The angiogenic factor bFGF is an autocrine growth factor for endothelial cells and hemangioma endothelial cells expressing bFGF in their cytosol during the proliferative phase. As suggested by J. Folkman and his group, assay of urinary bFGF appears useful in differentiating between hemangioma and vascular malformation and for follow up of treated patients.

Are angiogenic factors, cytokines, and soluble adhesion molecules prognostic factors in patients with renal cell carcinoma?

Angiogenesis has an important role in the progression of solid tumors. Therefore, we measured the blood levels (ELISA) of angiogenic factors [basic fibroblast growth factor (bFGF), hepatocyte growth factor/scatter factor, and vascular endothelial growth factor (VEGF)] and soluble adhesion molecules [E-selectin, intercellular adhesion molecule (ICAM-1), platelet endothelial cell adhesion molecule-1, and vascular cell adhesion molecule-1] in 76 consecutive patients with untreated renal cell carcinoma and 41 healthy controls to evaluate their prognostic value. The serum levels of bFGF, hepatocyte growth factor, and VEGF were significantly higher in patients with renal cancer than they were in healthy subjects. bFGF and VEGF values were significantly higher in patients with disseminated cancer (N+ and/or M+) than they were in those with undisseminated (M-N-) cancer: median = 27 pg/ml, range = 5-118, n = 15 versus median = 8 pg/ml, range = 1-149, n = 61 (P = 10(-4)) for bFGF; and median = 883 pg/ml, range = 200-2317, n = 15 versus median = 278 pg/ml, range = 0-1704, n = 61 (P = 0.006) for VEGF. The blood levels of ICAM-1 and vascular cell adhesion molecule-1 were significantly higher, and the levels of E-selectin and platelet endothelial cell adhesion molecule-1 were significantly lower in patients with renal cancer than they were in controls. Plasma ICAM-1 was higher in metastatic patients (M+) than they were in nonmetastatic (M-) patients: median = 687 ng/ml, range = 294-1091, n = 12 versus median = 408 ng/ml, range = 217-1375, n = 64 (P = 10(-4)). ICAM-1 and bFGF blood values were correlated with the size of the primary tumor. The interleukin 6 and tumor necrosis factor-alpha (TNF-alpha) values of these patients have been previously published and are included in the survival analysis. Univariate analysis showed that bFGF, ICAM-1, interleukin 6, and TNF-alpha, before treatment, were prognostic factors. In multivariate analysis for proportional hazard regression, only TNF-alpha was an independent prognostic indicator, with a normal plasma TNF-alpha being highly predictive for a good prognosis in patients with untreated renal cell carcinoma.