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31.
《Vaccine》2021,39(44):6529-6534
BackgroundAs people living with HIV (PLWH) are at risk for contracting Hepatitis B Virus (HBV), they should be screened for HBV and vaccinated if not immune. Seroconversion rates in PLWH receiving traditional recombinant HBV vaccines (Engerix-B® and Recombivax-HB®) have historically been low with at most 70% achieving immunity. In 2017, a recombinant, adjuvanted HBV vaccine (Heplisav-B®) was approved for use in HIV-negative patients.Heplisav-B® has shown superior seroprotection in this population compared to Engerix-B® and Recombivax-HB®, as well as interim analysis showing higher seropositivity rates in patients undergoing dialysis. However, its efficacy in PLWH is currently unknown. This study evaluates the rate of seroconversion following Heplisav-B® administration in PLWH with previous HBV vaccination failure.MethodsRetrospective, cross-sectional study at The Brooklyn Hospital Center’s HIV primary care clinic in Brooklyn, NY. HIV-positive adults who received at least two doses of Heplisav-B® and had previously failed to seroconvert after vaccination with Engerix-B® or Recombivax-HB® were included. The primary outcome is the percentage of PLWH who became seropositive following Heplisav-B®.ResultsA total of 67 patients met the inclusion criteria. Twenty-five (37.3%) PLWH had failed at least 2 courses of recombinant vaccines. Fifty-eight (86.6%) PLWH became seropositive (Anti-HBs > 10 mIU/mL) at least two months after completing Heplisav-B®. For the 9 (13.4%) patients that did not develop immunity, 3 (33%) had a detectable HIV RNA and 3 (33%) had a CD4 count < 200 cells/uL3.ConclusionsHeplisav-B® was highly effective in achieving immunity to HBV in PLWH who failed non-adjuvanted recombinant vaccines. 相似文献
32.
进行四项试验观察Baycox对柔嫩艾美尔球虫的作用及其对球虫免疫力影响。Baycox均以推荐浓度(25ppmToltrazuril)混入水中任鸡自由饮用。以2000卵囊剂量感染并立即给药的鸡,在感染后6-20d粪便中始终没有发现卵囊,表明Bayoox具有杀虫作用而不是抑虫作用。以8×10 ̄4卵囊剂量感染鸡,在感染前1d和感染后0、1、2、3、4、5d分别开始给药,根据血便数量和盲肠病变判断,Baycox的作用峰期是在感染后0-2d之间。感染后第4d再给药已无治疗作用。停药1d后,药物残效对感染仍显出一定的抗球虫作用,但是停药2d后,这种作用即基本消失。采用攻毒的方法表明Baycox不影响抗球虫免疫力的形成。 相似文献
33.
Requirement of HMGB1 and RAGE for the maturation of human plasmacytoid dendritic cells 总被引:8,自引:0,他引:8
Dumitriu IE Baruah P Bianchi ME Manfredi AA Rovere-Querini P 《European journal of immunology》2005,35(7):2184-2190
Dendritic cells (DC) are key components of innate and adaptive immune responses. Plasmacytoid DC (PDC) are a specialized DC subset that produce high amounts of type I interferons in response to microbes. High mobility group box 1 protein (HMGB1) is an abundant nuclear protein, which acts as a potent pro-inflammatory factor when released extracellularly. We show that HMGB1 leaves the nucleus of maturing PDC following TLR9 activation, and that PDC express on the plasma membrane the best-characterized receptor for HMGB1, RAGE. Maturation and type I IFN secretion of PDC is hindered when the HMGB1/RAGE pathway is disrupted. These results reveal HMGB1 and RAGE as the first known autocrine loop modulating the maturation of PDC, and suggest that antagonists of HMGB1/RAGE might have therapeutic potential for the treatment of systemic human diseases. 相似文献
34.
原发性肝癌经皮微波凝固治疗前后局部免疫活性细胞功能检测 总被引:18,自引:2,他引:16
目的:了解原发性肝癌经皮微波凝固治疗前、后局部免疫活性细胞功能变化。方法:C地38例病理诊断原发性肝癌,并接受超声导引下经皮微波凝固治疗的患者。分别治疗前及治疗后17d,超声导引下经皮用18G组织切割针于病灶及其周边肝组织取活检标本,取出的组织标本石蜡包埋,采用特异性单克隆抗体免疫组织化学染色,检测CD3^ 、CD56^ 、CD68^ 细胞及T淋巴细胞表面Fas配体;并在光镜下观察,用病理图像分析仪测量治疗前后、后阳性细胞直径、阳性细胞占单位面积百分比、T淋巴细胞Fas-L阳性表达率及治疗前后巨噬细胞内次级溶酶体变化。结果:治疗前肿瘤内仅有少量免疫细胞浸润,多数浸润的CD3^ 和CD56^ 细胞最大径小于10μm,CD68^ 细胞最大径小于18μm。治疗后病灶内浸润的CD3^ 、CD56^ 和CD68^ 细胞数量较治疗前明显增加,细胞体积明显增大(同治疗前相比CD3^ 细胞和CD56^ 细胞t和P值分别为3.48,-4.76和0.025,0.000,巨噬细胞t和P值分别为-2.46和0.028)。最大径大于10μm的CD3^ 和CD56^ 细胞分别由治疗前的10.4%和20.1%增至24.9%和30.2%,最大径大于18μm的CD68^ 细胞由10.2%增至33.4%。T淋巴细胞Fas-L阳性率由治疗前的7.2%增高至20.1%(P<0.01,巨噬细胞内次级溶酶体和T淋巴细胞内细胞器明显增多。结论:原发性肝癌经皮微波凝固治疗提高局部浸润免疫细胞的功能。 相似文献
35.
目的:了解喉癌患者围手术期细胞免疫的状况及手术相关因素对患者细胞免疫的影响;了解T淋巴细胞水平与喉癌临床特征,病程进展的关系。方法:应用SAP法检测喉癌术前2d及术后12d外周血CD3^ ,CD4^ ,CD8^ 细胞水平及CD4^ /CD8^ 比率的改变,并联系临床分期、淋巴结转移,复发综合分析。结果:喉癌患者CD3^ ,CD4^ ,CD8^ 细胞水平及CD4^ /CD8^比正常对照组明显下降;术后CD3^ ,CD4^ ,CD8^ 有进一步下降的倾向。晚期喉癌患者CD4^+细胞水平,CD4^ /CD8^ 比率明显下降(P<0.05)。淋 巴结转移者CD4^ /CD8^ 亦下降,CD8^ 细胞水平却相对升高;复发患者的CD8^ 细胞水平相对提高。结论:喉癌患者T淋 巴细胞免疫功能低下,全麻、手术创伤及术后复合因素是喉癌术后免疫功能进一步低下的原因。CD4^ ,CD8^ 细胞水平及CD4^ /CD8^ 比率是表明喉癌患者病期进展,淋巴结转移,复发的免疫学指标,围手术期需行免疫治疗。 相似文献
36.
《Immunobiology》2023,228(2):152348
Since its emergence about two years ago, the novel coronavirus has continued to be a challenge and threat to public health, struck most parts of the world, leaving more than half a billion cases of infection and more than five million deaths. Immune response abnormalities post-infection with SARS-CoV-2 have been reported, and the mechanisms that lead to them are still ambiguous. This study was conducted to evaluate some immunological markers in the serum samples of COVID-19 convalescent patients and investigate the association of these immunological signatures with their age and sex. The serum levels of immunoglobulin G, interleukin-1 beta, and interferon lambda-1 of 75 patients and 50 healthy control group members were measured, with 55 % males and 45 % females participating and ages ranging from 20 to 80 years. The measurement of the immunological signatures was performed using the enzyme-linked immunosorbent assay (ELISA). The result revealed highly significant elevated levels of the serum immunological signatures of the convalescent group in comparison to the control group, with P-values of 0.00001 for each signature. Moreover, age was observed to have an association with an elevated level of the immunological signatures as it increased in the elderly, whereas no association with sex was detected. The findings strongly suggest that COVID-19 infection results in a persistent inflammatory response, which leads to prolonged post-recovery symptoms. Post-COVID-19 syndrome necessitates additional research to clarify its pathophysiology, pathogenesis, and long-term implications. 相似文献
37.
支气管扩张感染加重的病原学及药敏分析 总被引:4,自引:0,他引:4
目的:为了解本地区支扩感染加重需住院患者的病原学及药敏情况,指导临床治疗。方法:用纤支镜取深部痰作培养和药敏以及血清IgG测定。结果:74例深部痰培养60例阳性,阳性率为81.1%,最常见的病原菌为假单孢菌属; 72例患者有 53例 IgG降低,平均值为 6. 5±1. 2g/L。结果:患者免疫功能低下和革兰氏阴性杆菌特别是铜绿假单抱杆菌感染是引起支扩感染加重住院的主要因素。在抗菌药物应用时宜选用对假单孢菌有效的药物。 相似文献
38.
Dietary micronutrients such as vitamins and trace minerals are known modulators of host immune responses against common pathogens.
In this respect, vitamin A and zinc have recently received increased attention. Severalin vivo andin vitro studies suggest that vitamin A may be a critical player in the mucosal immune responses in the respiratory and gastrointestinal
tracts, particularly in undernourished children. The effect may be mediated primarily by stabilization of the membrane of
mucosal epithelial cells, as well as enhanced leukocyte functions. The beneficial effect of vitamin A therapy in reducing
measles-associated morbidity and mortality suggests its crucial role in defenses against viral pathogens. Zinc is also known
affect leukocyte functions such as phagocytosis and T-lymphocyte-mediated immune responses. However, unlike vitamin A, zinc
has been investigated primarily for its effects on bacterial infections. Dietary supplementation or therapeutic treatment
with vitamin A and zinc may be a cheap yet effective means of preventing or treating infections in highly susceptible populations.
Additional studies, however, are required to better define the types of pathogens and the specific human populations that
may benefit from such therapy. 相似文献
39.
壳聚糖对荷肝癌小鼠的免疫调节作用 总被引:9,自引:0,他引:9
目的:观察壳聚糖对肝癌实体瘤(Heps)小鼠的抑瘤作用和免疫调节作用。方法:建立荷肝癌小鼠模型,观察壳聚糖对肿瘤生长和自然杀伤细胞(NKC)、巨噬细胞(MΦ)吞噬功能、T淋巴细胞转化功能的影响。结果:壳聚糖对小鼠Heps无明显抑制作用,低剂量壳聚糖可增加Heps荷瘤小鼠的细胞免疫功能,对MΦ吞噬功能有明显的提高作用。结论:壳聚糖对荷瘤小鼠的免疫功能具有调节作用。 相似文献
40.