Human alternatives to fetal bovine serum for the expansion of mesenchymal stromal cells from bone marrow.

Mesenchymal stromal cells (MSCs) are promising candidates for novel cell therapeutic applications. For clinical scale manufacturing, human factors from serum or platelets have been suggested as alternatives to fetal bovine serum (FBS). We have previously shown that pooled human serum (HS) and thrombin-activated platelet releasate in plasma (tPRP) support the expansion of adipose tissue-derived MSCs. Contradictory results with bone marrow (BM)-derived MSCs have initiated a comprehensive comparison of HS, tPRP, and pooled human platelet lysate (pHPL) and FBS in terms of their impact on MSC isolation, expansion, differentiation, and immunomodulatory activity. In addition to conventional Ficoll density gradient centrifugation, depletion of lineage marker expressing cells (RosetteSep) and CD271+ sorting were used for BM-MSC enrichment. Cells were cultured in medium containing either 10% FBS, HS, tPRP, or pHPL. Colony-forming units and cumulative population doublings were determined, and MSCs were maximally expanded. Although both HS and tPRP comparable to FBS supported isolation and expansion, pHPL significantly accelerated BM-MSC proliferation to yield clinically relevant numbers within the first two passages. MSC quality and functionality including cell surface marker expression, adipogenic and osteogenic differentiation, and immunosuppressive action were similar in MSCs from all culture conditions. Importantly, spontaneous cell transformation was not observed in any of the culture conditions. Telomerase activity was not detected in any of the cultures at any passage. In contrast to previous data from adipose tissue-derived MSCs, pHPL was found to be the most suitable FBS substitute in clinical scale BM-MSC expansion.

A multicenter phase 1 study of EMD 525797 (DI17E6), a novel humanized monoclonal antibody targeting αv integrins, in progressive castration-resistant prostate cancer with bone metastases after chemotherapy.

BACKGROUND: EMD 525797 (DI17E6) is a deimmunized, humanized monoclonal immunoglobulin G2 antibody against the αv subunit of human integrins. Blocking αv integrins may be an effective strategy for inhibiting prostate cancer (PCa) metastasis. OBJECTIVE: Evaluate EMD 525797 safety/tolerability and pharmacokinetics (PK) in castration-resistant PCa patients. Secondary objectives included antitumor activity assessments. DESIGN, SETTING, AND PARTICIPANTS: A phase 1 open-label study in 26 patients (four European centers). Eligible patients (≥ 18 yr) had histologically proven PCa with bone metastases after prior chemotherapy and evidence of progressive disease (PD) based on prostate-specific antigen (PSA) values. INTERVENTION: Patients received three intravenous EMD 525797 infusions (250, 500, 1000, or 1500 mg every 2 wk). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Treatment-emergent adverse events (TEAEs) and dose-limiting toxicities (DLTs) were assessed. PK parameters were calculated according to noncompartmental standard methods. Antitumor activity measures were response after 6 wk, changes in PSA levels, and pain interference total score. Descriptive statistics were used. RESULTS AND LIMITATIONS: Patients were treated for a mean of 16.8 ± 16.7 wk. No DLTs were reported in any of the cohorts. All patients experienced TEAEs, which were considered drug-related in 11 patients. Four deaths occurred during the trial and were considered not related to EMD 525797. EMD 525797 showed dose-dependent, nonlinear PK. Eighteen of 26 patients did not show PD for ≥ 18 wk. Two patients (500-mg cohort), treated for 42.4 and 76.3 wk, had clinically significant PSA reductions and pain relief, including one patient with confirmed partial response. This trial was not specifically designed to assess clinical activity, and further investigations are needed in randomized controlled trials. CONCLUSIONS: No DLTs were reported in any of the evaluated cohorts. There was evidence of clinical activity. For the currently ongoing phase 2 trial, EMD 525797 doses of 750 and 1500 mg every 3 wk were chosen. TRIAL REGISTRATION: NCT00958477 (EMR 62242-002).

Long-term effects of corticosterone on behavior, oxidative and energy metabolism of parietotemporal cerebral cortex and hippocampus of rats: comparison to intracerebroventricular streptozotocin.

We studied the effect of long-term application of corticosterone (CORT) s.c. the equivalent of cortisol in rats, on behavior, oxidative and energy metabolism in brain parietotemporal cortex and hippocampus of 1-year-old male Wistar rats. The data were compared with results derived from long-term and low dose intracerebroventricular application of the diabetogenic drug streptozotocin (STZ) known to inhibit the function of the neuronal insulin receptor and generating an insulin resistant brain state. CORT reduced both working and reference memory increasingly with time and running parallel to the STZ-induced deficit. The effect of CORT on the activities of the glycolytic enzymes hexokinase, phosphofructokinase, pyruvate kinase, glyceraldehyde-3-phosphodehydrogenase, lactate dehydrogenase and, in tricarboxylic acid cycle, alpha-ketoglutarate dehydrogenase equaled in both experimental conditions and in both regions studied: significant decreases of all enzyme activities except lactate dehydrogenase which increased between three and fourfold of normal. The CORT- and STZ-induced marked fall in ATP was in the same range in the regions studied. Differences became obvious in the concentration of creatine phosphate in parietotemporal cerebral cortex showing no decrease after CORT obviously due to a different susceptibility of the CORT-receptor. It is discussed that both CORT and STZ may act on the neuronal insulin receptor in a similar way. However, further studies are needed on the gene expression of insulin and the insulin receptor and its protein levels to clarify the exact action of CORT on the neuronal insulin receptor function.