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171.
Biologic effect and immunoisolating behavior of BMP-2 gene-transfected bone marrow-derived mesenchymal stem cells in APA microcapsules 总被引:2,自引:0,他引:2
Ding HF Liu R Li BG Lou JR Dai KR Tang TT 《Biochemical and biophysical research communications》2007,362(4):923-927
We investigated the encapsulation of BMP-2 gene-modified mesenchymal stem cells (MSCs) in alginate-poly-L-lysine (APA) microcapsules for the persistent delivery of bone morphogenic protein-2 (BMP-2) to induce bone formation. An electrostatic droplet generator was employed to produce APA microcapsules containing encapsulated beta-gal or BMP-2 gene-transfected bone marrow-derived MSCs. We found that X-gal staining was still positive 28 days after encapsulation. Encapsulated BMP-2 gene-transfected cells were capable of constitutive delivery of BMP-2 proteins for at least 30 days. The encapsulated BMP-2 gene-transfected MSCs or the encapsulated non-gene transfer MSCs (control group) were cocultured with the undifferentiated MSCs. The gene products from the encapsulated BMP-2 cells could induce the undifferentiated MSCs to become osteoblasts that had higher alkaline phosphatase (ALP) activity than those in the control group (p<0.05). The APA microcapsules could inhibit the permeation of fluorescein isothiocyanate-conjuncted immunoglobulin G. Mixed lymphocyte reaction also indicates that the APA microcapsules could prevent the encapsulated BMP-2 gene-transfected MSCs from initiating the cellular immune response. These results demonstrated that the nonautologous BMP-2 gene-transfected stem cells are of potential utility for enhancement of bone repair and bone regeneration in vivo. 相似文献
172.
During winter, increased thermoregulatory demands coincide with limited food availability necessitating physiological tradeoffs among expensive physiological processes resulting in seasonal breeding among small mammals. In the laboratory, short winter-like day lengths induce regression of the reproductive tract, but also enhance many aspects of immune function. It remains unspecified the extent to which bolstered immune responses in short days represent enhanced immune function per se compared to long days or represents energetic disinhibition mediated by the regression of the reproductive tract. Cohabitation of male Siberian hamsters with intact female conspecifics can block short-day reproductive regression. We sought to determine whether female cohabitation could also block the enhanced immune function associated with short days. Adult male Siberian hamsters were housed in long or short day lengths in one of three housing conditions: (1) single-housed, (2) housed with a same sex littermate, or (3) housed with an ovariectomized female. Delayed-type hypersensitivity (DTH) responses were assessed after 8 weeks of photoperiod treatment. Housing with an ovariectomized female was not sufficient to block short-day reproductive regression, but prevented short-day enhancement of DTH responses. Housing with a male littermate did not alter reproductive or immune responses in either photoperiod. These data suggest that short day enhancement of immune function is independent of photoperiod-mediated changes in the reproductive system. 相似文献
173.
Numerous immunotherapy trials have been carried out in prostate cancer (PC) patients, with induction of antigen-specific T cells in some cases. Despite this capability, limited success is seen in terms of tumor regression or survival. In this review, we discuss the evidence for tumor escape strategies that may contribute to vaccine failure in the setting of PC. These include defects in antigen presentation, production of immunosuppressive substances, induction of T cell death, T cell receptor dysfunction, and the presence of tolerogenic dendritic cells and regulatory T cells inside prostate tumors. It is clear that novel strategies aimed at preventing tumor escape, such as small molecular weight inhibitors of immunosuppressive molecules, adoptive transfer of TCR transgenic T cells, removal of Tregs, combined with anti-androgen therapy and prostate-specific vaccines, need to be examined further in PC patients.This article is a symposium paper from the conference Progress in Vaccination against Cancer 2005 (PIVAC 5), held in Athens, Greece, on 20–21 September 2005. 相似文献
174.
175.
通过黄芩苷抗生物制剂过敏反应的研究,在不影响疫苗免疫效果的前提下,解决注射生物制剂引起的过敏反应问题,为生物制品与天然药物相结合开辟了一条新路。采用生物制品过敏试验常规检测方法。黄芩苷使用安全,抗过敏作用明显,具有抑制肥大细胞脱颗粒和降低毛细血管通透性作用。黄芩苷与生物制品相结合,初步试验结果表明有抗动物过敏反应的效果。 相似文献
176.
177.
Mühling J Burchert D Langefeld TW Matejec R Harbach H Engel J Wolff M Welters ID Fuchs M Menges T Krüll M Hempelmann G 《Amino acids》2007,33(3):511-524
Summary. We examined the effects of DON [glutamine-analogue and inhibitor of glutamine-requiring enzymes], alanyl-glutamine (regarding
its role in neutrophil immunonutrition) and alanyl-glutamine combined with L-NAME, SNAP, DON, β-alanine and DFMO on neutrophil
amino and α-keto acid concentrations or important neutrophil immune functions in order to establish whether an inhibitor of
•NO-synthase [L-NAME], an •NO donor [SNAP], an analogue of taurine and a taurine transport antagonist [β-alanine], an inhibitor
of ornithine-decarboxylase [DFMO] as well as DON could influence any of the alanyl-glutamine-induced effects. In summary,
irrespective of which pharmacological, metabolism-inhibiting or receptor-mediated mechanisms were involved, our results showed
that impairment of granulocytic glutamine uptake, modulation of intracellular glutamine metabolisation and/or de novo synthesis
as well as a blockade of important glutamine-dependent metabolic processes may led to significant modifications of physiological
and immunological functions of the affected cells. 相似文献
178.
《International journal for parasitology》2022,52(8):569-579
Schistosomiasis is a globally important helminthic disease of both humans and animals, and is the second most common parasitic disease after malaria. Although praziquantel is extensively used for treatment of parasitic diseases, drug resistance has been reported. Therefore, new drugs and effective vaccines are needed for continuous control of schistosomiasis. Eggs produced by schistosomes are responsible for the occurrence and spread of schistosomiasis. Revealing the reproductive mechanism of schistosomes will help to control this disease. In this study, the proteomic profiles of single-sex infected female worms and bisexual infected mature female worms of Schistosoma japonicum at 18, 21, 23 and 25 days p.i. were identified with isobaric tags for relative quantitation-coupled liquid chromatography–tandem mass spectrometry. Differentially expressed proteins were subsequently used for bioinformatic analysis. Six highly expressed differentially expressed proteins in mature female worms were selected and long-term interference with small interfering RNA (siRNA) was conducted to determine biological functions. SiRNA against S. japonicum translationally controlled tumour protein (SjTCTP) resulted in the most significant effect on the growth and development of MF worms. Sjtctp mRNA expression gradually increased over time with a high level of expression maintained at 25–42 days p.i., while levels were significantly higher in mature female worms than male and SF worms. The subsequent animal immune protection experiments showed that recombinant SjTCTP (rSjTCTP) reduced the number of adults by 44.7% (P < 0.01), average egg burden per gram of liver by 57.94% (P < 0.01), egg hatching rate by 47.57% (P < 0.01), and oviposition of individual females by 43.16%. rSjTCTP induced higher levels of serum IgG, IL-2, and IL-10 in mice. Collectively, these results show that SjTCTP is vital to reproduction of female worms and, thus, is a candidate antigen for immune protection. 相似文献
179.
Inflammation is widely accepted to play a major role in atherosclerosis and other cardiovascular diseases. However, the exact mechanism(s) by which inflammation exerts its pathogenic effect remains poorly understood. A number of oxidatively modified proteins have been associated with cardiovascular disease. Recently, attention has been given to the oxidative compound of malondialdehyde and acetaldehyde, two reactive aldehydes known to covalently bind and adduct macromolecules. These products have been shown to form stable malondialdehyde–acetaldehyde (MAA) adducts that are reactive and induce immune responses. These adducts have been found in inflamed and diseased cardiovascular tissue of patients. Antibodies to these adducted proteins are measurable in the serum of diseased patients. The isotypes involved in the immune response to MAA (i.e., IgM, IgG, and IgA) are predictive of atherosclerotic disease progression and cardiovascular events such as an acute myocardial infarction or coronary artery bypass grafting. Therefore, it is the purpose of this article to review the past and current knowledge of aldehyde-modified proteins and their role in cardiovascular disease. 相似文献
180.
《Zoology (Jena, Germany)》2015,118(6):386-393
The blood trematode Gigantobilharzia huronensis typically infects passerine birds and has not been reported in other orders of wild birds. However, in the summer of 2011 in Tempe, Arizona, USA, mourning doves (Zenaida macroura; order: Columbiformes) were collected with infections of G. huronensis. This is the first report of a natural schistosome infection found in wild populations of doves. We sought to determine if G. huronensis infections alter the general body condition and physiology of doves, a seemingly unlikely host for this parasite. Specifically, we hypothesized that birds infected with schistosomes would exhibit reduced weight as well as increased markers of stress and immune system activation. Adult male mourning doves (n = 14) were captured using walk-in style funnel traps. After weighing the birds, blood and mesenteric tissue samples were collected. We measured biomarkers of stress including circulating heat shock proteins (HSPs) 60 and 70, as well as oxidized lipoproteins in schistosome-infected and non-infected birds. Indices of immune system reactivity were assessed using agglutination and lysis assays in addition to determining the leukocyte to erythrocyte ratios and prevalence of hemoparasite infections from blood smears. Schistosome-infected mourning doves had significantly increased oxidative stress and evidence of HSP70 mobilization. There was no evidence for weight loss in schistosome-infected birds nor evidence of significant immune system activation associated with schistosome infection. This may be a reflection of the small sample size available for the study. These findings suggest that schistosome infections have pathological effects in doves, but the lack of mature worms suggests that infected birds in this sampling may not have been suitable hosts for parasite maturation. 相似文献