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Lehmann J Jüngel A Lehmann I Busse F Biskop M Saalbach A Emmrich F Sack U 《Journal of autoimmunity》2000,15(3):301-313
The objective of this study was to verify whether isolated rheumatoid arthritis (RA) synovial fibroblasts induce chronic arthritis in SCID mice, in analogy to whole tissue pieces. Fibroblasts were isolated from the synovial membrane of four RA patients (or controls) by out-growth and repeated-passage culture. Following flow-cytometry characterization, 2x10(6)cells were transferred into the left knee joint of SCID mice. The development of arthritis was assessed by joint swelling and histological changes. Human and murine cytokines were measured in vitro in co-cultures (or Transwelltrade mark systems) of human and murine cells. Purified RA synovial fibroblasts, but not healthy synovial or skin fibroblasts, induced hu/mu arthritis within 6 weeks. In-vitro secretion of murine and human interleukin(IL)-6, as well as murine tumour necrosis factor (TNF)-alpha, indicated cross-activation between murine macrophages and human RA fibroblasts. Soluble-factor mechanisms proved more effective than cell-contact mechanisms. Purified RA fibroblasts can, alone, induce hu/mu SCID arthritis. The cytokine profile suggests that xenogeneic interaction between human fibroblasts and murine macrophages may determine the sequence of events leading to hu/mu arthritis. 相似文献
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Production, characterization, and application of monoclonal antibodies to Vibrio cholerae O139 synonym Bengal. 总被引:7,自引:3,他引:7 下载免费PDF全文
F Qadri T Azim A Chowdhury J Hossain R B Sack M J Albert 《Clinical and Vaccine Immunology : CVI》1994,1(1):51-54
Mouse monoclonal antibodies (MAbs) were derived against acetone-treated whole cells of the newly recognized Vibrio cholerae O139 serogroup which is causing epidemics of cholera-like disease in India and Bangladesh. Four MAbs specifically recognized the lipopolysaccharide antigens of V. cholerae O139. MAbs ICL9 and ICL13 were of the immunoglobulin M (IgM) isotype, ICL11 was of the IgG3 isotype, and ICL12 was of the Ig2b isotype. A fifth MAb, ICL10, of the IgG2b isotype cross-reacted with V. cholerae O91. All five MAbs recognized V. cholerae O139 in an enzyme-linked immunosorbent assay, slide agglutination test, motility inhibition test, and indirect immunofluorescence test. During a 1-month evaluation of these MAbs in our clinical laboratory, all 86 cases diagnosed as V. cholerae O139 by a rabbit polyclonal antiserum were also detected by these MAbs, establishing their utility as highly sensitive and specific diagnostic reagents. With these MAbs, it should now be possible to screen for the V. cholerae O139 serogroup in epidemic and endemic diarrhea cases and in environmental and food samples. 相似文献
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The use of specialized coils to improve signal-to-noise ratios in magnetic resonance (MR) imaging is an important innovation. The role of surface coils has not yet been well defined, but it seems likely that they will be routinely used for clinical imaging of the orbit, neck, and spine. Surface coils have important limitations that make other designs, such as "closely coupled" volume coils, attractive for some applications, especially for limb imaging. With improvement in our ability to visualize anatomy with MR imaging, specialized radio frequency coils may provide new imaging capabilities for clinical problems that were not previously considered to be indications for diagnostic imaging. 相似文献
37.
Kim Han Komudi Singh Matthew J. Rodman Shahin Hassanzadeh Yvonne Baumer Rebecca D. Huffstutler Jinguo Chen Julin Candia Foo Cheung Katherine E. R. Stagliano Mehdi Pirooznia Tiffany M. Powell-Wiley Michael N. Sack 《Nutrients》2021,13(5)
Intermittent fasting and fasting mimetic diets ameliorate inflammation. Similarly, serum extracted from fasted healthy and asthmatic subjects’ blunt inflammation in vitro, implicating serum components in this immunomodulation. To identify the proteins orchestrating these effects, SOMAScan technology was employed to evaluate serum protein levels in healthy subjects following an overnight, 24-h fast and 3 h after refeeding. Partial least square discriminant analysis identified several serum proteins as potential candidates to confer feeding status immunomodulation. The characterization of recombinant IGFBP1 (elevated following 24 h of fasting) and PYY (elevated following refeeding) in primary human CD4+ T cells found that they blunted and induced immune activation, respectively. Furthermore, integrated univariate serum protein analysis compared to RNA-seq analysis from peripheral blood mononuclear cells identified the induction of IL1RL1 and MFGE8 levels in refeeding compared to the 24-h fasting in the same study. Subsequent quantitation of these candidate proteins in lean versus obese individuals identified an inverse regulation of serum levels in the fasted subjects compared to the obese subjects. In parallel, IL1RL1 and MFGE8 supplementation promoted increased CD4+ T responsiveness to T cell receptor activation. Together, these data show that caloric load-linked conditions evoke serological protein changes, which in turn confer biological effects on circulating CD4+ T cell immune responsiveness. 相似文献
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L Ozzello CM De Rosa EW Blank K Cantell RL Ceriani DV Habif Sr 《Breast cancer research and treatment》1993,25(3):265-276
Summary An immunoconjugate composed of natural interferon (nIFN) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN on the injected tumors. Further enhancement was obtained when nIFN or nIFN together with Mc5 (at a dose 10 times larger than that present in nIFN/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of125I-nIFN/Mc5 by the tumors was greater and its elimination slower than for125I-nIFN alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy. 相似文献
39.
Lee BJ Ryu SG Choi HG Kim CK Parrott KA Ayres JW Sack RL 《Archives of pharmacal research》1997,20(6):555-559
The three different batches of an oral sustained release melatonin (MT) delivery system were prepared by aqueous-based fluid-bed coating of the sugar spheres for the evaluation ofin vitro release characteristics and plasma concentration profiles in human subjects. The MT contents in 20% coated sugar spheres of three batches (B1, B2 and B3) were 3.3+/-0.08, 2.4+/-0.1 and 2.5+/-0.13 mg per gram of coated sugar spheres, respectively. The release profiles of three different batches had a very similar fashion. However, the release half-lives (T(50%)) of MT from B1, B2 and B3 was 3.70+/-0.2, 5.2+/-0.2 and 4.9+/-0.07h, respectively. Plasma concentration profiles of sustained release 0.2mg melatonin-loaded sugar spheres containing 10% immediate release melatonin in gelatin capsules (B1 and B2) were then evaluated in human subjects. Thein vivo plasma concentration profiles of the two batches (B1 and B2) were very similar each other and located between the physiological endogenous ranges. The time to reach the peak concentration (T(max)) was more advanced in case of B1 when compared to B2. However, there was no statistically significant difference in the maximum concentration (C(max)) and the area under the curve (AUC) between B1 and B2. The AUC of melatonin-loaded sugar spheres containing 10% and 20% immediate release MT in human subjects had a good linearity between dose and AUC, regardless of the fraction of immediate release MT, indicating the first order elimination process of MT within these doses. The current oral sustained release MT delivery system may be utilized to treat circadian rhythm disorders if it is proven to be more clinically useful when compared to immediate release MT. 相似文献
40.
Chromosomal rearrangement segregating with adrenoleukodystrophy: associated changes in color vision. 总被引:1,自引:1,他引:0 下载免费PDF全文
M Alpern G H Sack Jr D H Krantz J Jenness H Zhang H W Moser 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(20):9494-9498
A patient from a large kindred with adrenoleukodystrophy showed profound disturbance of color ordering, color matching, increment thresholds, and luminosity. Except for color matching, his performance was similar to blue-cone "monochromacy," an X chromosome-linked recessive retinal dystrophy in which color vision is dichromatic, mediated by the visual pigments of rods and short-wave-sensitive cones. Color matching, however, indicated that an abnormal rudimentary visual pigment was also present. This may reflect the presence of a recombinant visual pigment protein or altered regulation of residual pigment genes, due to DNA changes--deletion of the long-wave pigment gene and reorganized sequences 5' to the pigment gene cluster--that segregate with the metabolic defect in this kindred. 相似文献