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31.
Andrea J. Radtke Evelyn Kandov Bradley Lowekamp Emily Speranza Colin J. Chu Anita Gola Nishant Thakur Rochelle Shih Li Yao Ziv Rafael Yaniv Rebecca T. Beuschel Juraj Kabat Joshua Croteau Jeremy Davis Jonathan M. Hernandez Ronald N. Germain 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(52):33455
32.
目的观察健脾温肾软坚解毒方、康艾注射液联合低剂量化疗对老年脾肾两虚型晚期非小细胞肺癌患者瘤灶、免疫功能及无进展生存期的影响。方法将80例老年脾肾两虚型晚期非小细胞肺癌患者随机分为治疗组和对照组,每组40例。对照组予常规剂量化疗,治疗组予健脾温肾软坚解毒方、康艾注射液联合低剂量化疗。化疗2个周期后,观察两组患者瘤灶、免疫功能的变化情况,随访患者的无进展生存期。结果①试验期间,对照组脱落2例,试验组无脱落,最终完成试验者78例,其中治疗组40例,对照组38例。②两组实体瘤疗效比较,差异无统计学意义(P0.05)。③化疗1个周期与化疗前组内比较,两组血清NK、CD3~+、CD4~+、CD8~+水平差异无统计学意义(P0.05);化疗2个周期与化疗前组内比较,治疗组血清CD8~+水平升高(P0.05),对照组血清NK、CD3~+、CD4~+水平降低(P0.05)。化疗1个周期后组间比较,治疗组血清CD3~+、CD4~+水平高于对照组(P0.05);化疗2个周期后组间比较,治疗组血清NK、CD3~+、CD4~+水平高于对照组(P0.05)。④两组患者中位无进展生存时间均为4.5个月,差异无统计学意义(P0.05)。结论健脾温肾软坚解毒方、康艾注射液联合低剂量化疗能有效控制老年肺肾两虚型晚期非小细胞肺癌患者的瘤灶变化,并有利于稳定血清NK、CD3~+和CD4~+水平,保护患者的免疫功能。 相似文献
33.
《Vaccine》2020,38(42):6578-6584
Q-VAX® is a vaccine used to prevent Q fever. Administration of the vaccine is complicated by the need to ensure, using intradermal and serological tests, that individuals have no prior immunity. Previous studies suggest that the vaccine is highly efficacious and long-lasting in adults. However, there has been no systematic follow-up of vaccine efficacy and the longevity of immunity using population-level data. We aimed to investigate the vaccine failure rate and duration of immunity in previously vaccinated individuals. We formulated a retrospective cohort study design within a linked data. We used a Q fever vaccination registry linked to Q fever notifications and hospital admissions (1991–2016) in the state of Queensland, which has Australia’s highest incidence of Q fever. Q-VAX® failure was defined as occurrence of Q fever > 14 days’ after vaccination. The incidence of Q fever in vaccinated and unvaccinated individuals was 5.40 (95% CI: 3.65, 7.72) and 89.50 (95% CI: 70.50, 112.00]) per 100,000 person-years of follow-up, respectively. The hazard ratio (HR) for Q fever was 0.07 (95% CI: 0.04, 0.10) in non-immune vaccinated compared with immune unvaccinated individuals. The overall vaccine effectiveness was found to be 94.37% suggesting that Q-VAX® is highly effective at preventing Q fever. However, the greater incidence observed in unvaccinated individuals considered immune during the pre-vaccination screening may suggest that pre-vaccination screening is sub-optimal among this study population. 相似文献
34.
35.
Yang Liu Xiaojia Liu Na Zhang Mingxiao Yin Jingwen Dong Qingxuan Zeng Genxiang Mao Danqing Song Lu Liu Hongbin Deng 《药学学报(英文版)》2020,10(12):2299-2312
Programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) blocking therapy has become a major pillar of cancer immunotherapy. Compared with antibodies targeting, small-molecule checkpoint inhibitors which have favorable pharmacokinetics are urgently needed. Here we identified berberine (BBR), a proven anti-inflammation drug, as a negative regulator of PD-L1 from a set of traditional Chinese medicine (TCM) chemical monomers. BBR enhanced the sensitivity of tumour cells to co-cultured T-cells by decreasing the level of PD-L1 in cancer cells. In addition, BBR exerted its antitumor effect in Lewis tumor xenograft mice through enhancing tumor-infiltrating T-cell immunity and attenuating the activation of immunosuppressive myeloid-derived suppressor cells (MDSCs) and regulatory T-cells (Tregs). BBR triggered PD-L1 degradation through ubiquitin (Ub)/proteasome-dependent pathway. Remarkably, BBR selectively bound to the glutamic acid 76 of constitutive photomorphogenic-9 signalosome 5 (CSN5) and inhibited PD-1/PD-L1 axis through its deubiquitination activity, resulting in ubiquitination and degradation of PD-L1. Our data reveals a previously unrecognized antitumor mechanism of BBR, suggesting BBR is small-molecule immune checkpoint inhibitor for cancer treatment. 相似文献
36.
《Vaccine》2020,38(39):6141-6152
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. 相似文献
37.
Jianbing Huang Jiagen Li Sufei Zheng Zhiliang Lu Yun Che Shuangshuang Mao Yuanyuan Lei Ruochuan Zang Chengming Liu Xinfeng Wang Lingling Fang Nan Sun Jie He 《Cancer science》2020,111(6):1876-1886
The tumor microenvironment (TME) is a vital component of tumor tissue. Increasing evidence suggests their significance in predicting outcomes and guiding therapies. However, no studies have reported a systematic analysis of the clinicopathologic significance of TME in lung adenocarcinoma (LUAD). Here, we inferred tumor stromal cells in 1184 LUAD patients using computational algorithms based on bulk tumor expression data, and evaluated the clinicopathologic significance of stromal cells. We found LUAD patients showed heterogeneous abundance in stromal cells. Infiltration of stromal cells was influenced by clinicopathologic features, such as age, gender, smoking, and TNM stage. By clustering stromal cells, we identified 2 clinically and molecularly distinct LUAD subtypes with immune active and immune repressed features. The immune active subtype is characterized by repressed metabolism and repressed proliferation of tumor cells, while the immune repressed subtype is characterized by active metabolism and active proliferation of tumor cells. Differentially expressed gene analysis of the two LUAD subtypes identified an immune activation signature. To diagnose TME subtypes practically, we constructed a TME score using principal component analysis based on the immune activation signature. The TME score predicted TME subtypes effectively in 3 independent datasets with areas under the receiver operating characteristic curves of 0.960, 0.812, and 0.819, respectively. In conclusion, we proposed 2 clinically and molecularly distinct LUAD subtypes based on tumor microenvironment that could be valuable in predicting clinical outcome and guiding immunotherapy. 相似文献
38.
《Vaccine》2015,33(49):6977-6982
Heterosubtypic immunity is defined as immune-mediated (partial) protection against an influenza virus induced by an influenza virus of another subtype to which the host has not previously been exposed. This cross-protective effect has not yet been demonstrated to the newly emerging avian influenza A viruses of the H7N9 subtype. Here, we assessed the induction of protective immunity to these viruses by infection with A(H1N1)pdm09 virus in a newly developed guinea pig model. To this end, ten female 12–16 week old strain 2 guinea pigs were inoculated intratracheally with either A(H1N1)pdm09 influenza virus or PBS (unprimed controls) followed 4 weeks later with an A/H7N9 influenza virus challenge. Nasal swabs were taken daily and animals from both groups were sacrificed on days 2 and 7 post inoculation (p.i.) with A/H7N9 virus and full necropsies were performed.Nasal virus excretion persisted until day 7 in unprimed control animals, whereas only two out of seven H1N1pdm09-primed animals excreted virus via the nose. Infectious virus was recovered from nasal turbinates, trachea and lung of all animals at day 2 p.i., but titers were lower for H1N1pdm09-primed animals, especially in the nasal turbinates. By day 7 p.i., relatively high virus titers were found in the nasal turbinates of all unprimed control animals but infectious virus was isolated from the nose of only one of four H1N1pdm09-primed animals.Animals of both groups developed inflammation of variable severity in the entire respiratory tract. Viral antigen positive cells were demonstrated in the nasal epithelium of both groups at day 2. The bronchi(oli) and alveoli of unprimed animals showed a moderate to strong positive signal at day 2, whereas H1N1pdm09-primed animals showed only minimal positivity. By day 7, only viral antigen positive cells were found after H7N9 virus infection in the nasal turbinates and the lungs of unprimed controls. Thus infection with H1N1pdm09 virus induced partially protective heterosubtypic immunity to H7N9 virus in (isogenic) guinea pigs that could not be attributed to cross-reactive virus neutralizing antibodies. 相似文献
39.
《Vaccine》2021,39(24):3259-3269
BackgroundRespiratory syncytial virus (RSV) is an important viral pathogen responsible for severe infection of the lower respiratory tract in children under the age of 5 years. No vaccines against RSV are currently in clinical use. Vaccine-associated enhanced respiratory disease (ERD) caused by excess Th2 type responses was observed in a clinical trial of formalin-inactivated RSV (FI-RSV) in antigen-naïve infants. Thus, inducing a balanced immune response is a crucial issue in the development of an RSV vaccine.MethodsIn this study, we constructed, expressed, and purified a recombinant RSV vaccine candidate (i.e., HRØ24) containing the two heptad repeat regions and the antigenic sites Ø, II, and IV of the RSV F protein. The RSV vaccine candidate was intranasally administrated to BALB/c and C57BL/6 mice in combination with virus-like particles (VLPs) derived from the core protein of the hepatitis B virus (HBc). Mucosal immunity to HRØ24 was then assessed.ResultsIntranasal administration of HBc VLPs in combination with HRØ24 induced serum IgGs against HRØ24 as well as lung HRØ24-specific sIgAs in both C57BL/6 and BALB/c mouse models. The secretion of IFN-γ from splenocyte re-stimulation and an elevated ratio of serum IgG2a to IgG1 indicated that the immune response induced by the HBc VLPs/HRØ24 mixture was Th1-biased. Weight loss of <5% and no to low eosinophil infiltration was observed in histological analysis of the lung following a challenge with the RSV A2 strain. These results suggest that the HBc VLPs/HRØ24 combination conferred substantial partial protection against RSV-induced illness in mice.ConclusionsLong-term immunity to RSV-induced illness was achieved via intranasal vaccination using a mixture of HBc VLPs and HRØ24 in mouse models. 相似文献
40.