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21.
The separation of viable tumor-infiltrating lymphocytes (TIL) from surgical biopsies of human solid tumors was achieved by velocity sedimentation at unit gravity or by discontinuous density gradients. The two methods were adapted to small volumes and cell numbers not exceeding 1 × 108. The recovery, purity and composition of the TIL-enriched fractions were comparable in the two methods. Density gradients were more rapid, simpler and more practical for preparation under sterile conditions of TIL from clinical material than velocity sedimentation. Lymphocytes in the TIL-enriched fractions obtained by either of the methods were poorly responsive to mitogens. This poor responsiveness is a characteristic of the human TIL and seems to be related to effects exerted by tumor cells.  相似文献   
22.
A 42-kDa fragment from the C terminus of major merozoite surface protein 1 (MSP1) is among the leading malaria vaccine candidates that target infection by asexual erythrocytic-stage malaria parasites. The MSP1(42) gene fragment from the Vietnam-Oak Knoll (FVO) strain of Plasmodium falciparum was expressed as a soluble protein in Escherichia coli and purified according to good manufacturing practices. This clinical-grade recombinant protein retained some important elements of correct structure, as it was reactive with several functional, conformation-dependent monoclonal antibodies raised against P. falciparum malaria parasites, it induced antibodies (Abs) that were reactive to parasites in immunofluorescent Ab tests, and it induced strong growth and invasion inhibitory antisera in New Zealand White rabbits. The antigen quality was further evaluated by vaccinating Aotus nancymai monkeys and challenging them with homologous P. falciparum FVO erythrocytic-stage malaria parasites. The trial included two control groups, one vaccinated with the sexual-stage-specific antigen of Plasmodium vivax, Pvs25, as a negative control, and the other vaccinated with baculovirus-expressed MSP1(42) (FVO) as a positive control. Enzyme-linked immunosorbent assay (ELISA) Ab titers induced by E. coli MSP1(42) were significantly higher than those induced by the baculovirus-expressed antigen. None of the six monkeys that were vaccinated with the E. coli MSP1(42) antigen required treatment for uncontrolled parasitemia, but two required treatment for anemia. Protective immunity in these monkeys correlated with the ELISA Ab titer against the p19 fragment and the epidermal growth factor (EGF)-like domain 2 fragment of MSP1(42), but not the MSP1(42) protein itself or the EGF-like domain 1 fragment. Soluble MSP1(42) (FVO) expressed in E. coli offers excellent promise as a component of a vaccine against erythrocytic-stage falciparum malaria.  相似文献   
23.
Specific anti-human T-cell serum was prepared in rabbits by multiple subcutaneous injections of human brain homogenates in incomplete Freund's adjuvant. The serum was exhaustively absorbed with human RBCs, lyophilized human liver, lyophilized normal human serum, and peripheral blood lymphocytes from patients with chronic lymphocytic leukemia (CLL). Specificity of the antiserum for human T lymphocytes was tested by indirect immunofluorescence. It stained 70 to 80% of lymphocytes in circulation, 95% of thymus, 27 to 35% of spleen, 5 to 10% of tonsil lymphocytes, and over 90% of phytohemagglutinin-stimulated lymphocytes in vitro. Only T-dependent areas of cryostat-sectioned human lymph nodes stained with the antiserum. It did not stain circulating lymphocytes which formed HEAC rosettes, plasma cells in marrows of multiple myeloma patients or macrophages. After removal of HEAC rosettes by centrifugation in Ficoll-Hypaque, 75% of interface cells formed E rosettes and 65 to 75% stained with the antiserum. The antiserum was used in studies of lymphocytes in chronic and acute lymphocytic leukemias, lymphomas, and other lymphoproliferative diseases. Numbers and distribution in the circulation, spleen and nodes of lymphocytes bearing the T marker were significantly altered in patients with these disorders.  相似文献   
24.
The single-pass multiple-indicator-dilution (MID) technique was used to analyze postglomerular capillary permeability. Anesthetized mongrel dogs (n = 13) during mannitol diuresis received a pulse injection of 125I-albumin (plasma reference), [14C]inulin (glomerular reference), creatinine (interstitial reference), and a homogeneous [3H]dextran molecular weight marker 6,000-12,000 dalton in the left renal artery. Simultaneous left renal venous outflow and right and left urine were rapidly sampled. Left urine recoveries of creatinine, [14C]inulin, and [3H]dextran were identical, indicating no glomerular solute flux limitation. Progressive precession of the [14C]inulin and [3H]dextran renal vein curves relative to creatinine indicated increasing postglomerular limitation to solute flux proportional to molecular size. The postglomerular solute extraction (EPG) (renal vein upslope indicator/125I-albumin) varied inversely with postglomerular renal plasma flow (F), indicating diffusion limitation. Ouabain infusion into the left renal artery significantly reduced Na reabsorption but did not alter the EPG of [14C]inulin or [3H]dextran. Permeability-surface (PS) area products calculated from EPG and F ranged from 4.86 +/- 0.89 to 0.97 +/- 0.25 (SD) cm X s-1 X 100 g-1 for indicators 5,000-12,000 dalton. [14C]Inulin PS products remained constant for F greater than or equal to 2.50 ml X s-1 X 100 g kidney-1. PS[3H]dextran/PS[14C]In (n = 20, F greater than or equal to 2.5 ml X s-1) was used to calculate an effective postglomerular capillary pore radius, r = 55.5 +/- 7.6 (SD) A.  相似文献   
25.
Puromycin aminonucleoside--(PAN) treated rats develop acute nephrotic syndrome, mimicking human minimal lesion disease. In PAN nephrosis, podocyte detachment from the glomerular basement membrane (GBM) is the most likely cause of massive proteinuria in this model. To elucidate further the mechanisms of PAN-induced cellular dysfunction, new methods were employed to visualize podocyte cytoskeletal aggregation and to measure fibrillar attachment to the GBM. Adult Sprague-Dawley rats (n = 4/group) received a single tail-vein injection of PAN (75 mg/kg). On days 1, 2, 3, and 5 following injection, 24-hour urine collections were obtained for creatinine clearance, albuminuria, and total proteinuria. Then kidneys from each group were fixed by perfusion. Podocytic cytoskeleton was visualized by scanning electron microscopy. Subepithelial GBM staining and attachment fiber number, observed on digitized images of transmission electron micrographs, were quantitated with computer-based density analysis. A significant reduction in attachment fiber number in the GBM lamina rara externa occurred by day 5. On scanning electron micrographs, the secondary and tertiary podocytic processes were observed to be formed by highly aggregated cytoskeleton, which became partially disaggregated by day 3, was totally absent by day 5, and normalized by day 20. Immunogold staining revealed that actin and vinculin localized to the tertiary podocytic processes in the normal state were dispersed into the cell body following PAN. Podocyte cytoskeletal disaggregation precedes, and detachment from the GBM occurs simultaneously with, the onset of massive proteinuria in the PAN model.  相似文献   
26.
Natural killer (NK) cells (CD56(+)/CD3(-)) in the circulation of cancer patients were reported to have low NK activity and undergo spontaneous apoptosis. A possible relationship between apoptosis and impaired NK activity was studied by Annexin V-binding and NK-cell assays performed with peripheral blood mononuclear cells of patients with head and neck cancer (HNC), breast cancer (BC) and normal controls (NC). Cells stained with Annexin V (Anx) and antibodies to CD56, CD3, CD95, CD25, CD122 or CD132 were examined by flow cytometry. NK activity was tested against K562 targets in 4-h (51)Cr-release assays. The ratio of CD56(dim)/CD56(bright) NK cells was significantly different in patients vs. controls (10 vs. 16; p<0.01). A significantly greater percentage of CD56(dim) NK cells bound Anx in HNC patients (27+/-17%, median +/- SD) or BC (46+/-18%) than in NC (15+/-18%, p<0.04 and p<0.0002, respectively). CD56(dim) NK cells were preferentially targeted for apoptosis. NK activity was significantly lower in patients with HNC and BC than in NC (p<0.009). An inverse correlation between NK activity and the percent of Anx(+)CD56(dim) NK cells was observed in cancer patients (p =0.002) but not in NC. In patients, circulating CD56(dim) NK cells were targeted for apoptosis, leading to low levels of NK activity.  相似文献   
27.
With human volunteers inoculated at two sites with Haemophilus ducreyi, outcomes for a subject were not independent. In a reinfection trial, 2 of 11 previous pustule formers and 6 of 10 previous resolvers resolved all sites of infection. There was no correlation between serum bactericidal or phagocytic activity and outcome in the trial. These data indicate that different hosts are differentially susceptible to disease progression versus resolution in the model.  相似文献   
28.
Mast cells are important effector cells in IgE-associated immune responses, but also can contribute to host defense in certain examples of bacterial infection. We found that genetically mast cell-deficient WBB6F1-Kit(W)/Kit(W-v) mice exhibited more bacterial CFUs per spleen by 6 days after intraperitoneal injection of bioluminescent Salmonella typhimurium, and died more rapidly after infection, than did the congenic WBB6F1-Kit(+/+) wild type mice. Adoptive transfer of bone marrow-derived cultured mast cells of Kit(+/+) origin to the peritoneal cavity of Kit(W)/Kit(W-v) mice resulted in engraftment of mast cells in the peritoneal cavity and mesentery of the recipient mice, and the development of large numbers of mast cells in the spleen. However, such mast cell-engrafted Kit(W)/Kit(W-v) mice appeared sicker after intraperitoneal injection with S. typhimurium than did mast cell-deficient Kit(W)/Kit(W-v) mice, and exhibited numbers of CFUs of bacteria per spleen, and a survival curve, that were not significantly different than those of Kit(W)/Kit(W-v) mice. These results, when taken together with prior studies investigating the roles of mast cells in innate immunity, strongly suggest that whether mast cells can be shown to have a significant role in enhancing survival during bacterial infections may depend critically on the details of the particular experimental systems examined.  相似文献   
29.
A patient with von Hippel Lindau disease, bilateral symmetric renal cell carcinoma and pulmonary metastases treated with immunotherapy is the subject of this study. A left kidney and tumour mass were removed and the tumour cells used to make an autologous tumour/bacille Calmette–Guérin (BCG) vaccine as part of the treatment protocol. The patient's pulmonary nodules responded, but the remaining renal nodule subsequently grew. Samples of both tumours were obtained allowing for an internally controlled evaluation of the histological and immunohistologic differences between a responding and non-responding tumour nodule after therapy. The immunotherapy protocol is designed to promote a T cell response to autologous tumour. Cellular infiltrates were demonstrated in both responding and non-responding nodules compared with the pretreatment tumour specimen, but the responding nodule contained proportionately more T cells as well as markedly increased numbers of plasma cells and granulocytes. This suggested that several arms of the immune system may have been operative in the responding nodule.  相似文献   
30.
ContextResearch exists on energy balances (EBs) and eating disorder (ED) risks in physically active populations and occupations by settings, but the EB and ED risk in athletic trainers (ATs) have not been investigated.ObjectiveTo assess ATs'' energy needs, including the macronutrient profile, and examine ED risk and pathogenic behavioral differences between sexes (men, women) and job statuses (part time or full time) and among settings (college or university, high school, nontraditional).DesignCross-sectional study.SettingFree living in job settings.Patients or Other ParticipantsAthletic trainers (n = 46; male part-time graduate assistant ATs = 12, male full-time ATs = 11, female part-time graduate assistant ATs = 11, female full-time ATs = 12) in the southeastern United States.Main Outcome Measure(s)Anthropometric measures (sex, age, height, weight, body composition), demographic characteristics (job status [full- or part-time AT], job setting [college/university, high school, nontraditional], years of AT experience, exercise background, alcohol use), resting metabolic rate, energy intake (EI), total daily energy expenditure (TDEE), EB, exercise energy expenditure, macronutrients (carbohydrates, protein, fats), the Eating Disorder Inventory-3, and the Eating Disorder Inventory-3 Symptom Checklist.ResultsThe majority of participants (84.8%, n = 39) had an ED risk, with 26.1% (n = 12) engaging in at least 1 pathogenic behavior, 50% (n = 23) in 2 pathogenic behaviors, and 10.8% (n = 5) in >2 pathogenic behaviors. Also, 82.6% of ATs (n = 38) presented in negative EB (EI < TDEE). Differences were found in resting metabolic rate for sex and job status (F1,45 = 16.48, P = .001), EI (F1,45 = 12.01, P = .001), TDEE (F1,45 = 40.36, P < .001), and exercise energy expenditure (F1,38 = 5.353, P = .026). No differences were present in EB for sex and job status (F1,45 = 1.751, P = .193); χ2 analysis revealed no significant relationship between ATs'' sex and EB (= 0.0, P = 1.00) and job status and EB ( = 2.42, P = .120). No significant relationship existed between Daily Reference Intakes recommendations for all macronutrients and sex or job status.ConclusionsThese athletic trainers experienced negative EB, similar to other professionals in high-demand occupations. Regardless of sex or job status, ATs had a high ED risk and participated in unhealthy pathogenic behaviors. The physical and mental concerns associated with these findings indicate a need for interventions targeted at ATs'' health behaviors.  相似文献   
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