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L Neale

Publications and source records attributed to L Neale.

9 recordsLinked to original sources
PubMed1989

Human mononuclear cell function after 4 degrees C storage during 1-G and microgravity conditions of spaceflight.

Future space missions of long duration may require that autologous leukocytes be stored in flight for infusion to restore normal immune competence in crewmembers. Peripheral blood mononuclear cells (PBMNCs), as leukocyte concentrates in autologous plasma and 2% dextrose, were stored in the microgravity conditions provided by the U.S. Space Shuttle Columbia (Mission 61-C). Activity of PBMNC after space flight was compared with that from a series of preflight ground control experiments, which demonstrated in culture a progressive daily loss in mitogen-stimulated protein synthesis at 24 h and thymidine uptake at 72 h after storage for 7 d at 4 degrees C. Post-storage viabilities were at least 90% as determined by trypan dye exclusion. A progressive reduction in the percentage of PBMNC expressing cell-surface phenotype markers, which was similar for monocytes, B cells, and T-cell subsets, also occurred after storage. The ability of PBMNC, stored for 8 d in Columbia's middeck, to become activated and proliferate in vitro was similar to that of cells that remained in identical flight lockers on the ground as 1-G controls, thus indicating that PBMNCs were not adversely affected by storage under microgravity conditions.

Benzoates↗
PubMed1988

Operation Everest II: alterations in the immune system at high altitudes.

We investigated the effects on immune function after progressive hypobaric hypoxia simulating an ascent to 25,000 ft (7620 m) over 4 weeks. Multiple simultaneous in vitro and in vivo immunologic variables were obtained from subjects at sea level, 7500 ft (2286 m), and 25,000 ft during a decompression chamber exposure. Phytohemagglutinin-stimulated thymidine uptake and protein synthesis in mononuclear cells were reduced at extreme altitudes. Mononuclear-cell subset analysis by flow cytometry disclosed an increase in monocytes without changes in B cells or T-cell subsets. Plasma IgM and IgA but not IgG levels were increased at altitudes, whereas pokeweed mitogen-stimulated in vitro IgG, IgA, and IgM secretion was unchanged. During exposure to 25,000 ft, in vitro phytohemagglutinin-stimulated interferon production and natural killer-cell cytotoxicity did not change statistically, but larger intersubject differences occurred. IgA and lysozyme levels (nasal wash) and serum antibodies to nuclear antigens were not influenced by altitude exposure. These results suggest that T-cell activation is blunted during exposure to severe hypoxemia, whereas B-cell function and mucosal immunity are not. Although the mechanism of altered in vitro immune responsiveness after exposure to various environmental stressors has not been elucidated in humans, hypoxia may induce alterations in immune regulation as suggested by in vitro immune assays of effector-cell function.

Adult↗
PubMed1975

Soluble proteins of bronchopulmonary secretions from patients with cystic fibrosis, asthma, and bronchitis.

The concentrations of nine plasma proteins were determined by quantitative immunoelectrophoresis in sputum specimens from 29 patients with cystic fibrosis (CF) and from 24 patients with severe asthma and chronic bronchitis. The results suggested that the population of CF patients could be divided into two groups in spite of an absence of difference in clinical status between the groups. Average concentrations of seven plasma proteins in sputum of group I CF patients were identical with those in sputum of patients with bronchitis, but the average concentrations of six of these proteins in sputum from group II CF patients were higher than those in specimens from the bronchitic patients and were similar to corresponding concentrations in sputum from patients with asthma, all of whom were examined while in status asthmaticus. The average concentrations of 14 secretory proteins were the same in all sputum specimens whether or not they were produced by patients with cystic fibrosis, asthma or bronchitis. It was concluded that the concentrations in the bronchopulmonary secretions of proteins associated with host defence were not diminished in patients with cystic fibrosis, and failure to produce adequate concentrations of proteins with antimicrobial activity was unlikely to be responsible for the above average susceptibility to chest infection in cystic fibrosis. It is suggested that there exists a group of CF patients in whom a pulmonary allergic reaction generates an inflammatory response as severe as that characterizing status asthmaticus and that this response could be detrimental.

Adult↗