Secretion of angiogenic proteins by human multipotent mesenchymal stromal cells and their clinical potential in the treatment of avascular osteonecrosis.

Osteonecrosis is a frequent complication after treatment for childhood leukemia and other steroid-based therapies. The success rate of core decompression surgery is limited. Therefore, we evaluated relevant biological characteristics of human multipotent mesenchymal stromal cells (MSCs) in vitro. MSCs cultured under low-oxygen tensions showed decreased proliferation and differentiation into bone. However, these MSCs secreted significant amounts of vascular endothelial-derived factor in the presence of interferon-gamma. These in vitro results with potential effects on neovascularization and bone regeneration as well as findings in animal models prompted us to treat five patients with steroid-induced osteonecrosis of the femur by core decompression surgery and instillation of expanded autologous MSCs. Within 3 weeks of culture, sufficient numbers of MSCs were generated using animal protein-free culture conditions. No chromosomal aberrations were detected by matrix-based comparative genomic hybridization. Application of MSCs during core decompression was feasible and safe. Median follow-up is 16 months and the patients in this pilot study reported clinical improvement. Formation of mineralized bone in the osteonecrotic cavity was proven by computed tomography. Taken together, MSCs display biological properties that may add to the efficiency of surgical treatment in osteonecrosis and should be evaluated in larger patient cohorts.

Animal serum-free culture conditions for isolation and expansion of multipotent mesenchymal stromal cells from human BM.

BACKGROUND: Multipotent mesenchymal stromal cells (MSC) have become important tools in regenerative and transplantation medicine. Rapidly increasing numbers of patients are receiving in vitro-expanded MSC. Culture conditions typically include FSC because human serum does not fully support growth of human MSC in vitro (MSC(FCS)). Concerns regarding BSE, other infectious complications and host immune reactions have fueled investigation of alternative culture supplements. METHODS: As PDGF has long been identified as a growth factor for MSC, we tested media supplementation with platelet lysate for support of MSC proliferation. RESULTS: We found that primary cultures of BM-derived MSC can be established with animal serum-free media containing fresh frozen plasma and platelets (MSC(FFPP)). Moreover, MSC(FFPP) showed vigorous proliferation that was superior to classical culture conditions containing FCS. MSC(FFPP) morphology was equivalent to MSC(FCS), and MSC(FFPP) expressed CD73, CD90, CD105, CD106, CD146 and HLA-ABC while being negative for CD34, CD45 and surface HLA-DR, as expected. In addition to being phenotypically identical, MSC(FFPP) could efficiently differentiate into adipocytes and osteoblasts. In terms of immune regulatory properties, MSC(FFPP) were indistinguishable from MSC(FCS). Proliferation of PBMC induced by IL-2 in combination with OKT-3 or by PHA was inhibited in the presence of MSC(FFPP). DISCUSSION: Taken together, FCS can be replaced safely by FFPP in cultures of MSC for clinical purposes.

Postprandial release of cholecystokinin and pancreatic polypeptide in health and in gallstone disease: relationships with gallbladder contraction.

OBJECTIVES: The present study investigated endogenous postprandial release of cholecystokinin (CCK) and pancreatic polypeptide (PP) in relation to gallbladder dynamics in healthy subjects and patients with gallstones. METHODS: Gallbladder volume (by ultrasonography) and plasma concentrations of CCK and PP (by radioimmunoassay) were evaluated in 18 patients with gallstones and 14 healthy controls before and after administration of a semi-liquid test meal (250 ml, 1450 kJ). Gallbladder contractility was previously assessed on a separate day by intravenous infusion of ceruletide (2.5 ng/kg/min). RESULTS: Basal gallbladder volume was not different in patients (32 +/- 5.9 cm3) and controls (26 +/- 2.7 cm3). Postprandial gallbladder contractility was impaired in gallstone patients, who showed a reduced integrated response (-3718 +/- 349 vs. -5251 +/- 376 cm3/2 h, p < 0.01) and a delayed time to maximal gallbladder contraction (67 +/- 7.4 min vs. 37 +/- 2.4 min, p < 0.002). Maximal gallbladder contraction after ceruletide infusion was also reduced (44.1 +/- 5.0% vs. 72.5 +/- 3.2%, p < 0.001), but not delayed (15.8 +/- 2.4 vs. 15.7 +/- 1.4 min) in gallstone patients. Basal CCK and PP plasma levels were similar in both groups. Postprandial CCK release was impaired in gallstone patients, predominantly due to a decreased response over the first 30 min (3.8 +/- 1.8 vs. 20.0 +/- 4.9 pmol/L/30 min, p < 0.005). Postprandial PP release was not different between groups. A direct linear correlation between postprandial release of CCK and PP was found in healthy controls but not in patients with gallstones. Postprandial gallbladder volume at any moment was inversely correlated with CCK plasma levels in healthy subjects, but not in gallstone patients. No correlation between postprandial PP response and gallbladder dynamics was observed. CONCLUSIONS: Based on a multivariate logistic approach, a reduced and delayed postprandial gallbladder contractility and an impaired CCK release in the early postprandial phase are significantly associated with gallstone disease. Our data provide further evidence for the predominant role of endogenous postprandial CCK release in gallbladder contraction. A role for PP in modulating postprandial gallbladder dynamics is not supported.

[Simultaneous sonographic study of postprandial gastric emptying and gallbladder contraction]. / Simultane sonographische Untersuchung der postprandialen Magenentleerung und Gallenblasenkontraktion.

Postprandial gastric emptying and gallbladder contraction were assessed in 14 healthy subjects by means of ultrasonography after oral administration of a semi-liquid test meal (250 ml, 1450 kJ). For this purpose, cross-sectional areas of the gastric antrum and gallbladder volume were calculated and recorded over a period of 120 minutes using an annular-array-transducer. The semi-liquid test meal allowed suitable sonographic measurement of cross-sectional areas of the antrum in all 14 subjects. Mean half-time of gastric emptying was 47 minutes (range 17-72 minutes). Mean peak gallbladder contraction was 36% (range 17-60%) of initial volume and mean time to peak contraction was 65 minutes (range 20-120 minutes). The method described was found to be a practical and reliable procedure for the investigation of postprandial gastric emptying and gallbladder contraction. It is therefore of potential interest for application to a variety of clinical questions. A minor drawback involves the relative length and variability of time required for testing, owing to the wide range in the time-course of gastric emptying and gallbladder contraction across subjects. Normal ranges for defined test meals must be established in large control groups.