Inactivated influenza vaccine formulated with single-stranded RNA-based adjuvant confers mucosal immunity and cross-protection against influenza virus infection

Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4⁺ and CD8⁺ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.     

Mucosal features and granulocyte–monocyte-apheresis in steroid-dependent/refractory ulcerative colitis

BACKGROUND: Mucosa-infiltrated granulocyte neutrophils are an early characteristic of inflammation and the main histological feature of active ulcerative colitis. Mucosal healing has recently been indicated as an important tool in the evaluation of response to treatment. While several studies have stressed the efficacy of granulocyte-monocyte-apheresis in inducing clinical remission in active ulcerative colitis, few data are available on mucosal features. AIM: Aim of this study was to assess the effects of granulocyte-monocyte-apheresis on clinical and mucosal features in patients with ulcerative colitis, dependent upon or refractory to steroids. MATERIAL AND METHODS: From April 2004 to April 2005, 12 patients (5 females, 7 males, mean age 49 years, range 33-71 years), with mild-moderate ulcerative colitis (six left colitis, six pancolitis) dependent/refractory upon steroids were enrolled. Each patient was treated for a 5-week period with five cycles of granulocyte-monocyte-apheresis. Patients were evaluated at baseline and 1 week after the last apheresis by means of Global Physician Assessment, quality of life features, laboratory tests (erythrocyte sedimentation rate, CRP, full blood count, faecal calprotectine), endoscopy and histology. RESULTS: At week 6 of follow-up, complete mucosal healing was observed in 3 out of 12 patients, partial mucosal healing in 8 patients and no change in 1 patient. Clinical response was complete in 8 out of 12 patients. CONCLUSIONS: These data suggest that granulocyte-monocyte-apheresis induces an improvement both in clinical and mucosal lesions in steroid-dependent/refractory ulcerative colitis. Of note, the reduction in granulocyte infiltration and the improvement in mucosal lesions are accompanied by a reduction in faecal calprotectine.     

幽门螺杆菌尿素酶减毒鼠伤寒杆菌疫苗诱导小鼠粘膜免疫应答的研究

目的:观察口服减毒鼠伤寒杆菌活菌重组疫苗后小鼠的粘膜免疫应答状况。方法:将已构建成功的表达幽门螺杆菌(H.pylori)尿素酶B亚单位(UreB)的重组减毒鼠伤寒杆菌SL3261/pTC01-UreB口服免疫Balb/c小鼠,12周后检测肠液和血清中的特异性抗体反应。结果:疫苗组小鼠的肠液和血清中可分别检测到针对UreB的特异性抗体IgA和IgG,病理学检查显示疫苗组小鼠较对照组小鼠胃粘膜炎症程度差异无统计学意义。结论:表达H.pyloriUreB的减毒鼠伤寒杆菌SL3261/pTC01-UreB能够诱导小鼠产生抗H.pylori的粘膜免疫,可用作抗H.pylori感染的口服疫苗。     

黏膜瓣式食管胃吻合术抗反流的食管动力学研究

目的寻找一种实用有效的抗反流食管胃吻合术式。方法将食管癌和贲门癌患者464例随机分为黏膜瓣式食管胃吻合术组(A组,175例)、器械食管胃吻合术组(B组,151例)和单纯手工缝合食管胃一层吻合术组(C组,138例)。应用同位素测定胃食管反流指数和24h监测pH值,进行3组间的食管运动功能比较。结果同位素测定胃食管反流指数显示,A组反流阳性率为0,B组为33.3%,C组为6.7%。食管运动功能及24h监测pH显示,A组检测各项指标均接近正常值,B、C组与正常值比较,差异具有统计学意义(P<0.05)。结论黏膜瓣式食管胃吻合术式具有优异的抗反流功能,并能有效地防止食管癌、贲门癌术后反流性食管炎的发生。     

频闪喉镜对声带病理情况观察的研究

对1997年以来423例病态喉的频闪喉镜表现进行分析,结果显示声带有病理改变者其粘膜波、振幅、闭合相、运动周期性、对称性均有不同程度的变化,这种变化能直接反映声带病变的深度及范围,对喉部疾病的诊断、鉴别诊断、治疗指导及预后评价具有重要意义.     

旋毛虫Ts87重组蛋白诱导的小鼠黏膜免疫保护性研究

本实验探讨旋毛虫Ts87重组蛋白灌胃免疫小鼠诱导的黏膜免疫保护性作用。实验分对照组、佐剂组(霍乱毒素B亚单位组,CTB)和免疫组(CTB Ts87重组蛋白),灌胃免疫,间隔1周共免疫3次。末次免疫后第7天用400条旋毛虫感染期幼虫攻击,比较3组小鼠肠道成虫数、雌虫生殖力和肌幼虫数。且于末次免疫后第7天刮取肠黏液、取血检测特异性sIgA、IgG抗体水平。结果显示免疫组小鼠成虫减虫率、新生蚴减虫率、肌幼虫减虫率分别是81·34%、67·02%、84·49%;小鼠肠黏液sIgA水平及血清IgG水平显著高于对照组和佐剂组。结果表明Ts87重组蛋白黏膜免疫能够诱导小鼠产生抗旋毛虫的保护性免疫。灌胃免疫能显著提高肠黏液特异性sIgA水平,对促进肠道成虫的排出有明显作用。     

The advantage of mucosal immunization for polysaccharide-specific memory responses in early life

The aim of vaccination is to rapidly elicit protective immunity and generate memory for sustained protection. We studied the induction and persistence of polysaccharide (PS)-specific memory in neonatal and infant mice primed with pneumococcal conjugate (Pnc1-TT) by assessing the response to native pneumococcal PS (PPS-1), the kinetics of the PPS-1-specific IgG response to a second Pnc1-TT dose and affinity maturation. A subcutaneous (s.c.) Pnc1-TT booster induced a rapid increase in PPS-1-specific IgG, indicating efficient priming for memory by a single dose of Pnc1-TT already at 1 week of age. High levels were maintained for >12 weeks. However, a PPS-1 booster induced no response in neonatal or infant mice. The adjuvant LT-K63 significantly enhanced the IgG response and affinity to Pnc1-TT by both the s.c. and the intranasal (i.n.) route in all age groups. In neonatal and infant mice, PPS-1 and LT-K63 induced a booster response only when given i.n. following either s.c. or i.n. priming with Pnc1-TT and LT-K63. In contrast, PPS-1 with or without LT-K63 administered s.c. compromised the ongoing PPS-1-specific response elicited in neonatal mice by either s.c. or i.n. priming with Pnc1-TT and LT-K63. These results demonstrate the advantage of the mucosal route for elicitation of PS-specific memory responses in early life.     

Co-expression of CD8α in CD4+ T cell receptor αβ+ T cells migrating into the murine small intestine epithelial layer

We investigated the surface phenotype of CD3⁺CD4⁺ T cell receptor (TCR) αβ⁺ T cells repopulating the intestinal lymphoid tissues of C.B-17 scidlscid (severe-combined immunodeficient; scid) (H-2^d, L^d+) mice. CD4⁺ CD8^? T cells were cell sorter-purified from various secondary and tertiary lymphoid organs of congenic C.B-17 +/+ (H-2^d, L^d+) or semi-syngeneic dm2 (H-2^d, L^d?) immunocompetent donor mice. After transfer of 10⁵ cells into young scid mice, a mucosa-homing, memory CD44^hi CD45RB^lo CD4⁺ T cell population was selectively engrafted. Large numbers of single-positive (SP) CD3⁺ CD2⁺ CD28⁺ CD4⁺ CD^8? T cells that expressed the α₄ integrin chain CD49d were found in the spleen, the mesenteric lymph nodes, the peritoneal cavity and the gut lamina propria of transplanted scid mice. Unexpectedly, large populations of donor-type doublepositive (DP) CD4⁺ CD8α⁺ CD8β^? T cells with high expression of the CD3/TCR complex appeared in the epithelial layer of the small intestine of transplanted scid mice. In contrast to SP CD4⁺ T cells, the intraepithelial DP T cells showed low expression of the CD2 and the CD28 co-stimulator molecules, and of the α₄ integrin chain CD49d, but expressed high levels of the α_IEL integrin chain CD103. The TCR-Vβ repertoire of DP but not SP intraepithelial CD4⁺ T cells was biased towards usage of the Vβ6 and Vβ8 viable domains. Highly purified populations of SP and DP CD4⁺ T cell populations from the small intestine epithelial layer of transplanted scid mice had different abilities to repopulate secondary scid recipient mice: SP CD4⁺ T cells repopulated various lymphoid tissues of the immunodeficient host, while intraepithelial DP CD4⁺ T cells did not. Hence, a subset of CD3⁺ CD4⁺ TCRαβ⁺ T cells apparently undergoes striking phenotypic changes when it enters the microenvironment of the small intestine epithelial layer.