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971.
Baril L Briles DE Crozier P King JD Hollingshead SK Murphy TF McCormick JB 《Clinical and experimental immunology》2004,135(3):474-477
PspA and PsaA are Streptococcus pneumoniae surface proteins and potential pneumococcal vaccine antigens. The aim of this study was to characterize the transplacental transfer of antibodies to PspA and to PsaA. Paired mother and cord blood sera were obtained at delivery from 28 women. Concentrations of antibodies against PspA, PsaA, tetanus toxoid (vaccine-induced antibodies) and P6-outer membrane protein (OMP) of nontypeable Haemophilus influenzae were determined by ELISA. Antibodies to PspA of the IgG, IgG1 and IgG2 antibodies were also determined. The geometric mean percentage (GM%) of the paired infant:mother antibody were calculated. Results: The GM% of the infant:mother antibody concentrations against PspA, PsaA and P6-OMP antibodies were 64.7% (3.3 micro g/ml in infants vs. 5.1 micro g/ml in mothers), 50.4% (6.8 micro g/ml vs. 13.5 micro g/ml) and 66.7% (5.6 micro g/ml vs. 8.4 micro g/ml), respectively; the GM% of antibodies against tetanus toxoid was 104.5% (4.6 micro g/ml vs. 4.4 micro g/ml). Transplacental transfer of IgG1 was more efficient than that of IgG2 (approximately 120%vs. 65%). A transplacental transfer of antibodies to PspA and to PsaA exist. Moreover, these data suggest an active placental transfer of IgG1 antibodies to PspA since the concentration of these antibodies were consistently higher in cord sera than in the mother's sera. 相似文献
972.
目的: 应用治疗性肝再生模型进行胚胎干细胞(ESC)源性肝干细胞肝内移植, 观察其在肝组织替代、体内的生长分化及成瘤性等情况,为ESC移植在难治性肝病治疗中的临床应用提供实验依据。方法: 倒千里光碱+70%肝部分切除建立BALB/c小鼠的治疗性肝再生模型。用荧光示踪剂CFDA SE 标记移植细胞,将经淤胆血清“病理微环境”筛选体系筛选出的ESC源性肝干细胞经门静脉移植入治疗性肝再生模型小鼠肝内。然后荧光显微镜下观察,检测移植细胞体内分布、整合与肝细胞替代、体内生长分化等情况。2周后行白蛋白荧光免疫组化(双荧光染色)、血清白蛋白水平检测其功能状况。并通过观察其体内成瘤性对筛选出的ESC源性肝干细胞的安全性进行评估。结果: CFDA SE标记的ESC源性肝干细胞肝内移植1周,受体小鼠肝实质内可见散在绿色荧光分布。2周后,肝实质内绿色荧光分布区域明显扩大,且可见类似肝索样结构排列。共焦白蛋白荧光免疫组化(双荧光染色)结果表明,受体小鼠肝组织内可见标记细胞表达白蛋白阳性信号(呈黄色荧光),血清白蛋白水平则无明显差异(P>0.05)。6周内未见畸胎瘤形成,而将未分化的ESC移植入小鼠腋区皮下6周后则可见畸胎瘤形成。结论: 经淤胆血清“病理微环境”筛选体系筛选出的ESC源性肝干细胞移植入治疗性肝再生模型小鼠肝内后可有效整合入宿主肝板、在肝内能进一步生长分化并部分表达肝细胞功能。其安全性较好,6周内未见畸胎瘤形成。 相似文献
973.
Prakash N. Rao PhDa f Xin Cai MDa f Raman Venkataramanan PhDb Jeffrey L. Platt MDd Anthony Demetris MDa c Allen Thunberg MDe Connie Faltynek PhDe Thomas Starzl MD PhDa Prem Kumar MDf 《The Journal of allergy and clinical immunology》1995,95(6)
Reperfusion after ischemia results in endothelial cell injury and Kupffer cell activation. Inflammatory cytokines thus released can induce major histocompatibility complex antigens and increase the immunogenecity of the graft. An orthotopic rat liver allotransplant model was used to test the hypothesis that prevention of reperfusion injury by infusion of polyethylene glycol superoxide dismutase (PEG-SOD) would result in long-term allograft survival in the presence of subthreshold immunosuppressive dosages. ACI rats were used as donors, and Lewis strain rats as recipients. Orthotopic liver transplantation was initially performed to identify a subthreshold dose of the immunosuppressant FK-506, which would be unable to extend survival longer than control untreated rats with this strain combination. After testing three intramuscular FK-506 doses of 0.04, 0.08, and 0.16 mg/kg, it was observed that an FK-506 dose of 0.04 mg/kg/day for 14 days was unable to extend survival longer than in untreated recipients. This dose of FK-506 was used in combination with PEG-SOD at doses of 1000, 3000, 10,000, or 30,000 units. Recipient animals were treated intravenously with PEG-SOD as a loading dose to facilitate tissue penetration on day 1, and beginning on the day of transplantation, every 2 days for the duration of the study. Results of histologic studies and mean survival time were compared in untreated recipients and in rats treated with PEG-SOD plus 0.04 mg/kg/day FK-506. Mean survival time was increased significantly in these animals (p < 0.007) to 40.6 ± 25.6 days as compared with either untreated rats (10.0 ± 2.7 days) or rats treated with 0.04 mg/kg FK-506 alone (13.7 ± 4.2 days). Histologic examination demonstrated a significant reduction in the cellular infiltrate in rats treated with PEG-SOD plus FK-506, as compared with recipients treated with either agent alone or left untreated. Our results therefore suggest a potential approach to reducing immunosuppression in transplantation. (J ALLERGY CLIN IMMUNOL 1995;95:1276-81.) 相似文献
974.
Elevation of activated gamma delta T cell receptor bearing T lymphocytes in patients with autoimmune chronic liver disease. 下载免费PDF全文
To study the possible role of T cells bearing the gamma delta T cell receptor (TCR) heterodimer in the pathogenesis of autoimmune chronic active hepatitis (AI-CAH) and primary sclerosing cholangitis (PSC) in children, we measured levels of gamma delta+ T cells in the peripheral blood, assessed the proportion of cells bearing the disulphide-linked (BB3+) and non-disulphide-linked (A13+) subtypes of the receptor, and studied the co-expression of TCR-gamma delta and the activation markers HLA-DR and IL-2 receptor (IL-2R), and the memory cell marker CD45RO. Percentage levels and absolute numbers of gamma delta +T cells were higher in both groups of patients than in controls (P less than 0.01), mainly as a result of an increase in both percentage levels and absolute numbers of the A13+ subtype (P less than 0.001). Co-expression of IL-2R and TCR-gamma delta was not found in controls but was present in some patients with AI-CAH (four out of 17) and PSC (six out of 12) at low levels (median 2.3%, range 1.7-5.0%). Expression of HLA-DR on gamma delta+ T cells was similar in both groups of patients and controls. The majority of gamma delta+ T cells in children with AI-CAH and PSC also expressed CD45RO (74.7 +/- 18.4% and 79.8 +/- 24.3%, respectively) at levels significantly higher than in controls (53.3 +/- 17.2%, P less than 0.01). These results suggest that autoimmune liver diseases in children are associated with an expansion and activation of gamma delta+ T cells in the peripheral blood, which may be important in the pathogenesis of these disorders. 相似文献
975.
背景:研究表明外泌体具有促进骨再生的能力,但从胎牛血清中提取的外泌体是否可以促进骨形成仍存在争议。目的:观察胎牛血清外泌体对成骨细胞增殖能力的影响,从而为临床治疗骨破坏提供新思路。方法:通过超速离心法从胎牛血清中提取外泌体,采用透射电子显微镜和Western blot法验证外泌体是否提取成功;然后用10 mg/L胎牛血清外泌体干预成骨前体细胞MC3T3-E1,通过CCK-8实验检测外泌体对成骨细胞增殖能力的影响,Western blot检测外泌体对成骨细胞骨形态发生蛋白2和骨桥蛋白表达的影响。以不含外泌体的胎牛血清培养的MC3T3-E1细胞为对照组。结果与结论:①胎牛血清外泌体具有典型的脂质双层膜结构,大小在30-150 nm之间,外泌体表面标记因子CD81表达呈阳性,而微囊表面标记物CD40表达呈阴性;②外泌体组的增殖能力明显高于对照组,差异有显著性意义(P<0.05);外泌体组成骨标志性因子骨形态发生蛋白2和骨桥蛋白的表达水平明显高于对照组,差异有显著性意义(P<0.05);③结果表明,胎牛血清外泌体对成骨细胞的增殖起促进作用,可为临床治疗骨破坏提供新思路。 相似文献
976.
Soluble interleukin-2 receptor and soluble CD8 in liver cirrhosis and obstructive jaundice. 下载免费PDF全文
F Wagner C Assemi C Lersch R Hart M Classen 《Clinical and experimental immunology》1990,82(2):344-349
Activated lymphocytes secrete soluble interleukin-2 receptor (sIL-2R); CD8-positive lymphocytes secrete soluble CD8 (sCD8). Liver dysfunction in cirrhosis and obstructive jaundice is known to result in depressed cellular immunity. To evaluate whether this is due to real inactivation of the immune system, we measured sIL-2R and sCD8 in the serum of 46 patients with liver cirrhosis, 25 patients with obstructive jaundice, 32 patients with alcoholic liver disease without evidence of cirrhosis, 23 healthy persons and 43 patients with unrelated disease. sIL-2R in patients with cirrhosis (mean +/- s.e.m. 1499 +/- 140 U/ml) and obstructive jaundice (1517 +/- 204) was significantly increased compared with healthy subjects (363 +/- 29) and patients with unrelated diseases (685 +/- 92); sCD8 was significantly increased in patients with cirrhosis (737 +/- 63) but not in patients with obstructive jaundice (419 +/- 32) compared with healthy subjects (322 +/- 23) and patients with unrelated diseases (375 +/- 22). No difference was found between patients with cirrhosis due to alcohol abuse (n = 15) and chronic hepatitis B (n = 6). The Child-Pugh score had no significant influence on the sIL-2R or sCD8 value. In obstructive jaundice, sIL-2R correlated with alkaline phosphatase as marker of cholestasis (r = 0.43). These data show that in spite of the apparent depressed cellular immune defense both in liver cirrhosis and obstructive jaundice there is a general activation of the immune system but the CD8+ cell compartment is only activated in liver cirrhosis. The great changes of sIL-2R and sCD8 in liver dysfunction are important for the interpretation of studies using these serum proteins as markers for immune activation. 相似文献
977.
Yide Jin Laphalle Fuller Manuel Carreno Keith Zucker David Roth Violet Esquenazi Theodore Karatzas Sidney J. Swanson III Andreas G. Tzakis Joshua Miller 《Journal of clinical immunology》1997,17(2):140-153
Liver infiltrating lymphocytes (LIL) were isolated from HCV-positive (+) and HCV-negative (–) end-stage livers. Phenotypic analysis and functional studies using proliferative and lymphocytotoxic assays were performed with the isolated LIL. Two CD3+ lymphocyte populations were found in LIL using FITC anti-CD3 monoclonal antibodies (mAb). One was a bright fluorescence intensity population (as in PBL), and the other dim. We calculated the number of FITC-anti-CD3 mAbs bound per lymphocyte on PBL and LIL and found 80,040 ± 4628 and 39,615 ± 3932, respectively. Therefore, HCV+ and HCV– patient PBL contained approximately twice the number of CD3 molecules per cell than patient CD3+ LIL. LIL also contained approximately a threefold higher concentration of TCR+, CD4–CD8–, and CD56,16 (NK) cells than the patient PBL. Thus, a major subset of LIL is phenotypically similar to mouse NK1.1+ intermediate T cells. LIL freshly isolated from HCV+ livers exhibited weak CTL activity against EBV- or Con A-transformed lymphoblast targets infected with vaccinia–HCV recombinant virus (rHCV) or primary hepatocyte cultured cells. However, after in vitro coculture of LIL with rHCV, these cells developed a strong cytotoxicity for the above targets. In contrast, LIL from HCV– livers were not cytotoxic against the same targets. Histochemical studies (in situ) demonstrated that these hepatocytes express CD95, and stains demonstrated apoptosis. The HCV+ hepatocytes also express class I MHC molecules and ICAM-1. The addition of mAb specific for these adhesion molecules inhibited CML activity. Short-term cultured hepatocytes (targets) from HCV+ and HCV– patients produced low levels of cytokines IL-1, IL-2, IL-6, TNF, and IFN- but a high level of IL-8. It is speculated that LIL expressing reduced numbers of CD3 molecules may even function as immune regulators as proposed for intermediate T cells in mice. 相似文献
978.
W. H. Hörl W. Riegel C. Wanner M. Haag-Weber P. Schollmeyer H. Wieland H. Wilms 《Journal of molecular medicine (Berlin, Germany)》1989,67(17):907-918
Summary Various endocrine and metabolic disturbances associated with long standing uremia persist after kidney transplantation or arise from the use of immunosuppressive drugs. Hyperlipidemia for long time being implicated as the cause of corticosteroids is also observed in renal transplant recipients treated with cyclosporin A monotherapy. After conversion from cyclosporin to azathioprine serum cholesterol and triglyceride concentration fall, and elevation of LDL-cholesterol may also be reversed. There is a tendency for higher HDL-cholesterol in azathioprine and prednisolone treated transplant patients. Those patients who are at risk for clinically significant cholesterol elevations can be predicted by their pretransplant lipid levels, specifically the LDL-fraction. Risk-benefit ratio of conversion and of treatment with lipid-lowering drugs, especially with lovastatin, should be carefully examined, also in view of glucose intolerance.Higher incidence of diabetes mellitus requiring insulin therapy in cyclosporin treated transplant recipients has been reported. Cyclosporin may cause toxic effects on pancreatic beta-cells resulting in inhibition of insulin secretion. High doses of cyclosporin induce inhibition of glycogen synthesis in rat liver. Glucose intolerance is reversible after reduction of cyclosporin dose or conversion to azathioprine. Therefore glucose metabolism in kidney transplant recipients treated with cyclosporin should be carefully followed.Immunosuppressive therapy may affect reproductive function, arachidonate metabolism and renin-angiotensin-aldosterone system as well as posttransplant calcium and phophate metabolism.Endocrine and metabolic abnormalities are associated with long standing uremia. After successful kidney transplantation several observations are normalized but further complications arise from the use of immunosuppressive drugs. The present paper reviews various endocrine and metabolic disturbances described following renal transplantation. 相似文献
979.
Meniscal fibrocartilage autografts, homografts, glutaraldehyde treated homografts and glutaraldehyde treated xenografts were inserted into articular defects in the rabbit patello-femoral groove. They appeared capable of restoring a functional articular surface. Considerable variation in the type of bond formed between the host and graft occurred but no evidence of rejection was observed. This tissue would appear to offer potential for restoring localized articular osteochondral defects. 相似文献
980.
J. HAU P. SVENDSEN J. CHEMNITZ B. TEISNER J.G. WESTERGAARD 《American journal of reproductive immunology (New York, N.Y. : 1989)》1983,3(3):124-126
ABSTRACT: Two pregnancy-associated murine proteins, PAMP-1 and PAMP-2, have been found to be immunologically cross-reacting analogues to the human proteins pregnancy zone protein (PZP) and pregnancy-specific beta1-glycoprotien (SP-1), respectively. In this study, the physiochemical and biological properties of the proteins are compared and the effect on pregnancy of administration of monospecific antibodies against the proteins is reported. 相似文献