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Study design:Adult human olfactory bulb neural stem cells (OBNSCs) were isolated from human patients undergoing craniotomy for tumor resection. They were genetically engineered to overexpresses green fluorescent protein (GFP) to help trace them following engraftment. Spinal cord injury (SCI) was induced in rats using standard laminectomy protocol, and GFP-OBNSC were engrafted into rat model of SCI at day 7 post injury. Three rat groups were used: (i) Control group, (ii) Sham group (injected with cerebrospinal fluid) and treated group (engrafted with OBNSCs). Tissues from different groups were collected weekly up to 2 months. The collected tissues were fixed in 4% paraformaldehyde, processed for paraffin sectioning, immunohistochemically stained for different neuronal and glial markers and examined with bright-field fluorescent microscopy. Restoration of sensory motor functions we assessed on a weekly bases using the BBB score.Objectives:To assess the therapeutic potential of OBNSCs-GFP and their ability to survive, proliferate, differentiate and to restore lost sensory motor functions following their engraftment in spinal cord injury (SCI).Methods:GFP-OBNSC were engrafted into a rat model of SCI at day 7 post injury and were followed-up to 8 weeks using behavioral and histochemical methods.Results:All transplanted animals exhibited successful engraftment. The survival rate was about 30% of initially transplanted cells. Twenty-seven percent of the engrafted cells differentiated along the NG2 and O4-positive oligodendrocyte lineage, 16% into MAP2 and β-tubulin-positive neurons, and 56% into GFAP-positive astrocytes.Conclusion:GFP-OBNSCs had survived for >8 weeks after engraftment and were differentiated into neurons, astrocytes and oligodendrocytes, The engrafted cells were distributed throughout gray and white matter of the cord with no evidence of abnormal morphology or any mass formation indicative of tumorigenesis. However, the engrafted cells failed to restore lost sensory and motor functions as evident from behavioral analysis using the BBB score test.

Recent reports about laboratory rodents indicate that parameters of the immune system, including total immune cell number in hematopoietic compartments and ability to elicit both specific and nonspecific immune responses, may be among the most sensitive indicators of environmental contaminant exposure. In several species of wild-caught and laboratory-exposed fish, altered monocyte chemotactic ability, chemiluminescent responses (metabolic oxidative burst), and phagocytosis have recently been found to be associated with exposure to polycyclic aromatic hydrocarbons and organometals, indicating that parameters of immunity may also served as potential sensitive markers of chemical exposure in fish. In the present experiments, Nile tilapia Oreochromis niloticusexposed to the organophosphate insecticide, chlorpyrifos, at a concentration of 1 µg/L displayed significantly lower total pronephros cell counts than did untreated controls. In addition, macrophages isolated from the pronephros of the treated fish had depressed phagocytic function relative to control fish. These data suggest that fish exposed to environmentally relevant levels of chlorpyrifos may be immunologically altered. Further, results of our study provide additional evidence that parameters of immune function may serve as sensitive biomarkers in fish exposed to environmental contaminants.

Nephelometry, an immunological technique widely used for the quantification of blood proteins, was adapted to provide a quantitative method of detecting Haemophilus influenzae capsular antigen in body fluids. Using specific antiserum directed against H. influenzae capsular antigen, samples of serum, cerebrospinal fluid, urine, and joint fluid from 38 cases of H. influenzae infections were analyzed. The results were compared for reliability to counterimmunoelectrophoresis, a widely used diagnostic tool. The nephelometric technique has the same advantages of speed and specificity as counterimmunoelectrophoresis and provides the clinician and researcher with a quantitative method that is as reliable as the qualitative counterimmunoelectrophoresis procedure. The method allowed directly quantitative readouts on patient specimens, with no necessity for serial dilutions or densitometric readings.

Poultry have a very limited number of resident macrophages in the normal steady-state respiratory tract. Thus, poultry must rely heavily on active migration of phagocytic cells to the lungs and air sacs in defending against respiratory pathogens. Intratracheal administration of a live, apathogenic Pasteurella multocida vaccine (Choloral; Clemson University strain) increased the number of avian respiratory phagocytes (ARP; obtained by lavage of lungs and air sacs) within 24 h by 3 orders of magnitude compared with the number of ARP obtained from mock-inoculated controls and from nonreacting chickens. Chickens yielding a high number of ARP did not show any sign of respiratory disease. Flow cytometric analysis of ARP that were exposed to 20 nonopsonized fluorescent microspheres per ARP for 30 min at 37 degrees C demonstrated a fivefold increase in the percentage of actively phagocytic cells in the ARP populations of stimulated chickens compared with the percentage of phagocytic ARP for mock-inoculated control birds. The phagocytic capacity (relative number of engulfed microspheres) of ARP from stimulated birds doubled during the same time. The flow cytometric observations were confirmed by fluorescence microscopy. These results indicate that activation by avirulent replicating agents of phagocytic cells of chicken to migrate to the respiratory tract may be a means of defending poultry against air sacculitis and pneumonia.

AbstractRecent reports about laboratory rodents indicate that parameters of the immune system, including total immune cell number in hematopoietic compartments and ability to elicit both specific and nonspecific immune responses, may be among the most sensitive indicators of environmental contaminant exposure. In several species of wild-caught and laboratory-exposed fish, altered monocyte chemotactic ability, chemiluminescent responses (metabolic oxidative burst), and phagocytosis have recently been found to be associated with exposure to polycyclic aromatic hydrocarbons and organometals, indicating that parameters of immunity may also served as potential sensitive markers of chemical exposure in fish. In the present experiments, Nile tilapia Oreochromis niloticusexposed to the organophosphate insecticide, chlorpyrifos, at a concentration of 1 μg/L displayed significantly lower total pronephros cell counts than did untreated controls. In addition, macrophages isolated from the pronephros of the treated fish had depressed phagocytic function relative to control fish. These data suggest that fish exposed to environmentally relevant levels of chlorpyrifos may be immunologically altered. Further, results of our study provide additional evidence that parameters of immune function may serve as sensitive biomarkers in fish exposed to environmental contaminants.