Immunological mechanisms of fecal microbiota transplantation in recurrent Clostridioides difficile infection

Fecal microbiota transplantation (FMT) is a successful method for treating recurrent Clostridioides difficile (C. difficile) infection (rCDI) with around 90% efficacy. Due to the relative simplicity of this approach, it is being widely used and currently, thousands of patients have been treated with FMT worldwide. Nonetheless, the mechanisms underlying its effects are just beginning to be understood. Data indicate that FMT effectiveness is due to a combination of microbiological direct mechanisms against C. difficile, but also through indirect mechanisms including the production of microbiota-derived metabolites as secondary bile acids and short chain fatty acids. Moreover, the modulation of the strong inflammatory response triggered by C. difficile after FMT seems to rely on a pivotal role of regulatory T cells, which would be responsible for the reduction of several cells and soluble inflammatory mediators, ensuing normalization of the intestinal mucosal immune system. In this minireview, we analyze recent advances in these immunological aspects associated with the efficacy of FMT.     

放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及对Th1/Th2免疫细胞比例的影响

目的探讨放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及其对辅助性T细胞1(Th1)/Th2细胞比例的影响。方法建立宫颈癌荷瘤小鼠模型,随机分为荷瘤组和放疗组,每组各10只,另设对照组10只。放疗组进行放疗干预14天,荷瘤组和对照组不治疗。放疗后4、6、8、10、12、14天测量肿瘤体积;末次治疗后,ELISA法测定血清干扰素-γ(IFN-γ)、白介素-2(IL-2)、IL-4、IL-10含量;计算抑瘤率、胸腺指数和脾脏指数;HE染色观察肿瘤组织学变化;TUNEL染色观察肿瘤组织细胞凋亡情况;流式细胞术检测脾脏Th1/Th2细胞比例;RT-qPCR和Western blot检测脾脏T盒子转录因子(T-bet)、GATA结合蛋白3(GABA-3)mRNA和蛋白表达。结果与荷瘤组比较,放疗组小鼠4、6、8、10、12、14天肿瘤体积及瘤质量减小,血清IL-2、IFN-γ升高,IL-4、IL-10降低,胸腺指数、脾脏指数升高,Th1细胞比例、Th1/Th2增加,Th2细胞比例减少,T-bet mRNA和蛋白及T-bet/GATA-3表达升高,GATA-3 mRNA和蛋白表达降低(P<0.05)。HE染色显示,荷瘤组肿瘤细胞数量较多,核大深染,无明显坏死;放疗组肿瘤细胞数量减少,出现大量坏死组织。TUNEL染色显示,荷瘤组TUNEL阳性细胞较少,放疗组TUNEL阳性细胞明显增多。结论放疗对宫颈癌荷瘤小鼠具有明显抑瘤作用,可能是通过调节T-bet/GATA-3表达,促进Th1/Th2分化平衡,增强机体免疫功能发挥作用。     

不同时间电针对直肠癌开腹手术患者围术期应激反应和免疫功能的影响

目的观察不同时点电针对直肠癌开腹手术患者围术期应激反应及免疫功能的影响。方法240例择期行直肠癌根治性开腹手术而住院的患者,随机分为A组、B组、C组、D组,每组60例。A组设为空白对照组,B组于手术前1 d、C组于手术前1 d和麻醉诱导前30 min、D组分别于手术前1 d、麻醉诱导前30 min及手术后1 d行电针。分别于手术前1 d电针前(T1)、麻醉诱导前电针前(T2)、术毕(T3)和手术后1 d电针后(T4)4个时间采集患者空腹外周静脉血,用Sysmex血细胞分析仪对白细胞与中性粒细胞进行计数;ELISA检测急性期C反应蛋白(CRP)与热反应蛋白70(HSP70)以及细胞因子白介素6(IL-6)、干扰素(IFN-g)、白介素4(IL-4)水平,并计算IFN-g与IL-4比值;采用流式细胞仪测定CD4、CD8的细胞含量并计算两者比值。结果HSP70与CRP水平、白细胞数与中性粒细胞数、IL-4与IL-6水平变化趋势均一致,4组T1、T2时间比较,差异无统计学意义(P>0.05);A组与B组T3和T4时间比较,差异无统计学意义(P>0.05);C组、D组T3和T4时间显著低于A组与B组(P<0.05);D组T4时间显著低于C组(P<0.05);4组T2时间与T1时间比较差异无统计学意义(P>0.05),T3时间高于T2时间(P<0.05),T4时间低于T3时间(P<0.05)。IFN-g变化不显著(P>0.05),IFN-g/IL-4、CD4/CD8变化趋势与以上相反。结论电针术前使用对直肠癌患者无显著疗效,但能够减轻术后应激反应和免疫抑制,并且随着电针次数的合理增加疗效更加显著。     

The potential for vaccination-induced herd immunity against the SARS-CoV-2 B.1.1.7 variant

We assess the feasibility of reaching the herd immunity threshold against SARS-CoV-2 through vaccination, considering vaccine effectiveness (VE), transmissibility of the virus and the level of pre-existing immunity in populations, as well as their age structure. If highly transmissible variants of concern become dominant in areas with low levels of naturally-acquired immunity and/or in populations with large proportions of < 15 year-olds, control of infection without non-pharmaceutical interventions may only be possible with a VE ≥ 80%, and coverage extended to children.     

免疫功能障碍与子宫内膜异位症发生发展的研究现状

子宫内膜异位症（endometriosis，EMs）是一种雌激素依赖性疾病，通常与慢性盆腔疼痛及不孕症有关，影响约10%～15%的育龄期妇女。近年免疫功能障碍已证明是子宫内膜碎片逆行后促进异位病灶生长的关键因素。EMs患者几乎所有的免疫细胞功能都发生了变化，例如T细胞反应性和NK细胞毒性降低；B细胞多克隆激活、抗体产生增加；腹腔单核细胞活化数量增加等。此外，EMs中存在的高雌激素环境以及雌激素受体亚型的异常分布也会影响免疫细胞的募集及功能。但是免疫功能异常是造成EMs的初始原因还是由于该疾病导致的结局尚存争议。     

刮痧力度及时间间隔对刮痧效果的影响

目的:观察不同力度对刮痧效果的影响,初步探讨刮痧的作用机制以及效应周期,进一步探究刮痧治疗的最佳间隔时间。方法:用自制的特殊刮痧板控制使刮痧频次等参数保持一致,分别以1N、3N和9N的力进行刮痧,通过ELISA方法检测刮痧后IL-1α、IL-6的变化,结合皮肤HE染色法探究不同力度刮痧对机体的影响,选择适合的刮痧力度,通过血常规和流式细胞术检测刮痧后不同时间点的白细胞总数、淋巴细胞总数及T细胞亚群等的变化,初步探讨刮痧的作用机制和效应周期。结果:1N的力度刮痧未引起明显的变化,9N的力度刮痧造成了较严重的皮肤损伤和大量炎性反应因子释放,3N的力度刮痧较为适中,引起了机体适度的应激反应。以3N的力度刮痧后,血液中白细胞总数和淋巴细胞总数及IL-1α、IL-6缓慢升高,在1 h到24 h之间达到峰值,之后缓慢下降,在72 h左右恢复正常水平。结论:3N的力比较适合于刮痧实验,在刮痧之后1 h到24 h,刮痧对免疫系统的增强作用达到峰值,在72 h左右回归正常值,初步提示可以开始下一次刮痧治疗。     

Data mining and analysis of scientific research data records on Covid-19 mortality,immunity, and vaccine development - In the first wave of the Covid-19 pandemic

Background and aimsCovid-19 is a global pandemic that requires a global and integrated response of all national medical and healthcare systems. Covid-19 exposed the need for timely response and data sharing on fast spreading global pandemics. In this study, we investigate the scientific research response from the early stages of the pandemic, and we review key findings on how the early warning systems developed in previous epidemics responded to contain the virus.MethodsWe conducted data mining of scientific literature records from the Web of Science Core Collection, using the topics Covid-19, mortality, immunity, and vaccine. The individual records are analysed in isolation, and the analysis is compared with records on all Covid-19 research topics combined. The data records are analysed with commutable statistical methods, including R Studio’s Bibliometrix package, and the Web of Science data mining tool.ResultsFrom historical analysis of scientific data records on viruses, pandemics and mortality, we identified that Chinese universities have not been leading on these topics historically. However, during the early stages of the Covid-19 pandemic, the Chinese universities are strongly dominating the research on these topics. Despite the current political and trade disputes, we found strong collaboration in Covid-19 research between the US and China. From the analysis on Covid-19 and immunity, we wanted to identify the relationship between different risk factors discussed in the news media. We identified a few clusters, containing references to exercise, inflammation, smoking, obesity and many additional factors. From the analysis on Covid-19 and vaccine, we discovered that although the USA is leading in volume of scientific research on Covid-19 vaccine, the leading 3 research institutions (Fudan, Melbourne, Oxford) are not based in the USA. Hence, it is difficult to predict which country would be first to produce a Covid-19 vaccine.ConclusionsWe analysed the conceptual structure maps with factorial analysis and multiple correspondence analysis (MCA), and identified multiple relationships between keywords, synonyms and concepts, related to Covid-19 mortality, immunity, and vaccine development. We present integrated and corelated knowledge from 276 records on Covid-19 and mortality, 71 records on Covid-19 and immunity, and 189 records on Covid-19 vaccine.     

Aspects of Langerhans cells and TNF-α in the cutaneous immunity of anogenital warts

BackgroundAnogenital warts are the leading sexually transmitted infection in patients seeking care at specialized clinics. They may display a vast array of forms, according to the interaction of the virus with the host's immunity. Cellular immunity is the epithelium's main form of defense against the virus, involving an active participation of the Langerhans cells and pro-inflammatory cytokines such as TNF-α.ObjectiveTo assess the epithelial immune response of anogenital warts in males, according to the number of lesions presented.MethodsThis is a prospective, cross-sectional study carried out at the dermatology outpatient clinic in a tertiary hospital. We included male patients over 18 years of age without comorbidities who had anogenital condylomata and no previous treatments.In order to evaluate the local epithelial immunity, the lesions were quantified, then removed and employed in CD1a immunohistochemistry assays for assessing the morphometry and morphology of Langerhans cells; TNF-α; reaction was used for determining cytokine positivity in the epithelium.Results48 patients were included in the study. There was no statistically significant difference as to the number of Langerhans cells, in their morphology, or the presence of TNF-α. However, patients presenting with more Langerhans cells in the lesions had cells with a star-like and dendritic morphology, whereas in those with a lower cell count had cells with a rounded morphology and no dendrites (p < 0.001).Study limitationsSmall number of patients analyzed.ConclusionThere was no difference in epithelial immunity between patients having few or many anogenital condyloma lesions as measured by the morphology and morphometry of Langerhans cells and TNF-α; positivity. Such an assessment employing immunity markers differing from the usual ones is expected to yield useful results.