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Background: Transplantation of olfactory ensheathing cells (OEC) and Schwann cells (SC) is a promising therapeutic strategy to promote axonal growth and remyelination after spinal cord injury. Previous studies mainly focused on the rat model though results from primate and porcine models differed from those in the rat model. Interestingly, canine OECs show primate-like in vitro characteristics, such as absence of early senescence and abundance of stable p75NTR expression indicating that this species represents a valuable translational species for further studies. So far, few investigations have tested different glial cell types within the same study under identical conditions. This makes it very difficult to evaluate contradictory or confirmatory findings reported in various studies. Moreover, potential contamination of OEC preparations with Schwann cells was difficult to exclude. Thus, it remains rather controversial whether the different glial types display distinct cellular properties., Results: Here, we established cultures of Schwann cell-free OECs from olfactory bulb (OB-OECs) and mucosa (OM-OECs) and compared them in assays to Schwann cells. These glial cultures were obtained from a canine large animal model and used for monitoring migration, phagocytosis and the effects on in vitro neurite growth. OB-OECs and Schwann cells migrated faster than OM-OECs in a scratch wound assay. Glial cell migration was not modulated by cGMP and cAMP signaling, but activating protein kinase C enhanced motility. All three glial cell types displayed phagocytic activity in a microbead assay. In co-cultures with of human model (NT2) neurons neurite growth was maximal on OB-OECs., Conclusions: These data provide evidence that OB- and OM-OECs display distinct migratory behavior and interaction with neurites. OB-OECs migrate faster and enhance neurite growth of human model neurons better than Schwann cells, suggesting distinct and inherent properties of these closely-related cell types. Future studies will have to address whether, and how, these cellular properties correlate with the in vivo behavior after transplantation.

A wide range of immune-modulating effects make IL-10 a potential therapeutic option in the treatment of numerous diseases pathophysiological based on a dysregulation of cytokine production. The background of this study was to investigate, whether the beneficial effects of a therapeutic immunosuppression with IL-10 may be countered by an increased risk for infections due to impaired effector cell functions of unspecific immunity. We demonstrated the in vitro effects of IL-10 on phagocytosis (P), intracellular killing (K), and chemotactic activity (C) by human neutrophils (PMN) and monocytes (MON) using Candida albicans as test strain and compared the results to the effects of prednisolone and GM-CSF. IL-10 reduced significantly the intracellular killing rate of PMN compared to untreated phagocytes (60 +/- 16% versus 68 +/- 13%, mean +/- SD, p = 0.0002). High dose IL-10 (100 ng/ml) had a stimulating effect on the percentage of phagocytizing MON (70.2 +/- 12.7% vs. 66.9 +/- 14.2%, p = 0.0436), without impairing intracellular killing. Prednisolone reduced significantly the Candida uptake by MON (57 +/- 18.1% vs. 66. 9 +/- 14.2%, p = 0.0019). In contrast to prednisolone, neither MON nor PMN chemotaxis was suppressed by IL-10. In conclusion, IL-10 had only marginal immunosuppressive effects on the unspecific immunity compared to prednisolone.

The pharmacokinetics of gatifloxacin (400 mg orally) and the influence of the antacid aluminum magnesium hydroxide (20 ml of Maalox 70) on the bioavailability of gatifloxacin in 24 healthy volunteers were assessed. In an open, randomized, six-period crossover study, the volunteers received either gatifloxacin alone (treatments A and D); aluminum magnesium hydroxide concomitant with gatifloxacin (treatment C); or aluminum magnesium hydroxide 2 h before (treatment B), 2 h after (treatment E), or 4 h after gatifloxacin administration (treatment F). Gatifloxacin concentrations were measured by a validated bioassay and high-performance liquid chromatography. Pharmacokinetics of a single 400-mg dose of gatifloxacin alone were characterized as follows (mean +/- standard deviation): peak concentration (Cmax), 3.8 +/- 0. 5 (treatment A) and 3.4 +/- 0.9 (treatment D) microgram/ml; time to Cmax, 1.4 +/- 0.8 (treatment A) and 1.7 +/- 0.7 (treatment D) h; area under the curve from time zero to infinity (AUC0-infinity), 33. 5 +/- 5.9 (treatment A) and 31.4 +/- 3.4 (treatment D) microgram. h/ml; urine recovery, (83 +/- 6)% (treatment A) and (84 +/- 8)% (treatment D). Comparison of the results obtained by bioassay showed a good correlation. Aluminum magnesium hydroxide administration 2 h before (treatment B) or concomitant with (treatment C) gatifloxacin decreased the Cmax by 45% (2.1 +/- 1.2 microgram/ml) or even 68% (1.2 +/- 0.4 microgram/ml) highly significantly (P < 0.01). AUC0-infinity was significantly reduced from 33.5 +/- 5.9 to 19.4 +/- 6.9 microgram. h/ml (by 42%) or even to 11.9 +/- 3.3 microgram. h/ml (by 64%) (P < 0. 01). If aluminum magnesium hydroxide was given 2 h after gatifloxacin (treatment E), there was no significant reduction of concentration in serum but AUC0-infinity was significantly reduced from 31.4 +/- 3.4 to 25.9 +/- 5.3 microgram. h/ml (18%) (P < 0.01). Aluminum magnesium hydroxide given 4 h after gatifloxacin (treatment F) showed no influence on the gatifloxacin pharmacokinetics. Therefore, the optimal time between gatifloxacin application and the intake of an aluminum-containing antacid should be 4 h.

Interleukin-10 (IL-10) has potent anti-inflammatory and immunosuppressive properties. The potential therapeutic benefit may be compromised by the down-regulation of the non-specific immune system and an increased risk of infection. We studied the effects of IL-10 on important functions of native and granulocyte-macrophage colony-stimulating factor (GM-CSF) activated neutrophils and monocytes, namely phagocytosis and membrane expression of the beta superset2-integrins and of the intercellular adhesion molecule-1 (ICAM-1). In order to simulate the in vivo situation closely, we used whole blood flowcytometric assays. The effects of IL-10 (0.05, 1, 10, 100 ng/ml) were compared to those of prednisolone (10 superset-8-10 superset-5 Mol/l), an approved immunosuppressive drug which is known to impair phagocyte function. - Incubation with IL-10 for three hours significantly attenuated the ability of neutrophils to phagocytose E.coli, particularly in lower concentrations. On the other hand, high IL-10 concentrations (10, 100 ng/ml) slightly augmented monocyte phagocytosis. Similarly, expression of the beta subset2-integrins and of ICAM-1 on monocytes was markedly enhanced with IL-10 concentrations in the range from 1 to 100 ng/ml and IL-10 showed strong synergistic effects with GM-CSF in the enhancement of monocyte receptor expression. Neutrophil adhesion molecule expression was not affected. Prednisolone suppressed the phagocytosis of both cell types in a dose-dependent fashion but hardly altered the receptor numbers. Our study indicates that IL-10 can behave as a de-activator as well as an activator on the non-specific immune system, depending on the cell type and the concentration.