Suppression of glucose-6-phosphate-isomerase induced arthritis by oral administration of transgenic rice seeds expressing altered peptide ligands of glucose-6-phosphate-isomerase

Objective: To investigate the effects of transgenic rice seeds expressing the altered peptide ligand (APL) of human glucose-6-phosphate-isomerase (hGPI_325–339) in mice model of GPI-induced arthritis (GIA).

Methods: We generated transgenic rice expressing T-cell epitope of hGPI_325–339 and APL12 contained in the seed endosperm. The transgenic rice seeds were orally administered prophylactically before the induction of GIA. The severity of arthritis and titers of serum anti-GPI antibodies were evaluated. We examined for IL-17 production in splenocytes and inguinal lymph node (iLN) cells, and analyzed the expression levels of functional molecules in splenocytes.

Results: Prophylactic treatment of GIA mice with APL12 transgenic (APL12-TG) rice seeds significantly reduced the severity of arthritis and titers of serum anti-GPI antibodies compared with non-transgenic (Non-TG) rice-treated mice. APL12-TG and hGPI_325–339 transgenic (hGPI_325–339-TG) rice seeds improved the histopathological arthritis scores and decreased IL-17 production compared with non-TG rice-treated mice. APL12-TG rice-treated GIA mice showed upregulation of Foxp3 and GITR protein in CD4?⁺?CD25?⁺?Foxp3^+?cells in the spleen compared with non-TG rice- and hGPI_325–339-TG rice-treated mice.

Conclusion: APL12-TG rice seeds improved the severity of GIA through a decrease in production of IL-17 and anti-GPI antibodies via upregulation of Foxp3 and GITR expression on Treg cells in spleen.     

Persimmon leaf flavonoid induces brain ischemic tolerance in mice

The persimmon leaf has been shown to improve cerebral ischemic outcomes; however, its mechanism of action remains unclear. In this study, mice were subjected to 10 minutes of ischemic preconditioning, and persimmon leaf flavonoid was orally administered for 5 days. Results showed that the persimmon leaf flavonoid significantly improved the content of tissue type plasminogen activator and 6-keto prostaglandin-F1 α in the cerebral cortex, decreased the content of thromboxane B2, and reduced the content of plasminogen activator inhibitor-1 in mice. Following optical microscopy, persimmon leaf flavonoid was also shown to reduce cell swelling and nuclear hyperchromatism in the cerebral cortex and hippocampus of mice. These results suggested that persimmon leaf flavonoid can effectively inhibit brain thrombosis, improve blood supply to the brain, and relieve ischemia-induced pathological damage, resulting in brain ischemic tolerance.     

Association between Haemagglutination inhibiting antibodies and protection against clade 6B viruses in 2013 and 2015

BackgroundThe epidemiology of the pandemic A(H1N1) virus has been changing as population immunity continues to co-evolve with the virus. The impact of genetic changes in the virus on human’s susceptibility is an outstanding important question in vaccine design. In a community-based study, we aim to (1) determine the genetic characteristics of 2009–2015 pandemic H1N1 viruses, (2) assess antibody response following natural infections and (3) assess the correlation of A/California/07/09 antibody titers to protection in the 2013 and 2015 epidemics.MethodsIn a household transmission study, serum specimens from 253 individuals in Managua, Nicaragua were analyzed. Combined nose and throat swabs were collected to detect RT-PCR confirmed influenza infection and virus sequencing. Hemagglutination inhibition assays were performed and the protective titer for circulating H1N1pdm was determined.ResultsClade 6B pandemic H1N1 viruses predominated in Nicaragua during the 2013 and 2015 seasons. Our household transmission study detected a household secondary attack rate of 17% in 2013 and 33% in 2015. Infected individuals, including vaccinees, showed an apparent antibody response to A/California/07/09. Baseline titers of A/California/07/09 antibodies were found to associate with protection in both seasons. A titer of ≥1:40 correlated to a 44% protection in children, a 29% protection in adults 15–49 years old and a 51% protection in adults 50–85 years old.ConclusionIn 2013 and 2015, antibody titers to A/California/07/09 associated with an infection risk reduction amongst exposed household contacts. This is consistent with a detectable vaccine effectiveness reported in a number of studies. Genetic changes in clade 6B viruses might have led to a reduced immunity in some whereas others might have been less affected. The use of human serologic data is important in virus characterization and if performed in a timely manner, could assist in vaccine strain selection.     

Profound CD4+ T lymphocytopenia in human immunodeficiency virus negative individuals,improved with anti-human herpes virus treatment

Lymphocytopenia and CD4+ T lymphocytopenia can be associated with many bacterial, fungal, parasite and viral infections. They can also be found in autoimmune and neoplastic diseases, common variable immunodeficiency syndrome, physical, psychological and traumatic stress, malnutrition and immunosuppressive therapy. Besides, they can also be brought into relation, without a known cause, with idiopathic CD4+ T lymphocytopenia. Among viral infections, the Retrovirus, specially the human immunodeficiency virus, is the most frequently cause. However, many acute viral infections, including cytomegalovirus and Epstein Barr virus can be associated with transient lymphocytopenia and CD4+ T lymphocytopenia. As is well known, transient lymphocytopenia and CD4+ T lymphocytopenia are temporary and overcome when the disease improves. Nonetheless, severe CD4+ T Lymphocytopenia associated with chronic infections by human herpes virus has not been reported. We describe 6 cases of human immunodeficiency virus negative patients, with chronic cytomegalovirus and Epstein Barr virus infections and profound lymphocytopenia with clinical symptoms of cellular immunodeficiency. These patients improved rapidly with ganciclovir or valganciclovir treatment. We claim here that it is important to consider the chronic human herpes virus infection in the differential diagnosis of profoundly CD4+ T lymphocytopenia etiology, when human immunodeficiency virus is absent, in order to start effective treatment and to determine, in future studies, the impact of chronic human herpes virus infection in human beings'' health.     

脱细胞气管基质材料的免疫原性及生物相容性研究

目的探讨经高氯酸钠（NaClO₄）处理后的脱细胞气管基质材料的免疫原性及其生物相容性。 方法取 2 月龄新西兰兔胫骨骨髓，采用全骨髓贴壁筛选法分离培养 BMSCs。取 10 只 6 月龄成年新西兰兔气管，修剪至每段 1.5 cm，随机分为对照组（A₁ 组，n=5），仅剥离气管外表面疏松结缔组织；实验组（B₁ 组，n=5）采用改良 NaClO₄ 浸泡法脱细胞处理。MTT 法检测两组支架浸提液的细胞毒性；免疫组织化学染色观察支架主要组织相容性复合物（major histocompatibility complex，MHC）类抗原表达。取生长状态良好的第 4 代 BMSCs 接种至两组支架，制备细胞-支架复合物，培养 48 h 时行 Giemsa 染色，倒置显微镜观察材料周围的细胞活性；7、14 d 扫描电镜观察支架上的细胞状态。取 10 只 6 月龄成年新西兰兔，随机分成对照组（A₂ 组，n=5）和实验组（B₂ 组，n=5），分别于颈背部皮下皮囊埋植已制备的新鲜气管和脱细胞气管。术后行大体观察，并于术后 5、10、15、20、25、30 d 分析血清免疫球蛋白 IgM 和 IgG 含量的动态变化，术后 30 d 行 HE 染色观察。 结果MTT 检测示，B₁ 组浸提液的细胞增殖情况与 A₁ 组或纯培养基阴性对照组比较，差异无统计学意义（P>0.05）；免疫组织化学染色观察示，B₁ 组支架经脱细胞处理后可显著降低基质材料的抗原性。细胞-支架复合物培养 48 h Giemsa 染色示，两组材料周围的细胞贴壁生长良好。培养 7、14 d 扫描电镜观察示，细胞在 A₁ 组气管材料外壁上贴附良好，呈扁平的圆形、椭圆形，细胞排列紧密，成簇分布；细胞在 B₁ 组气管材料外壁上呈单片状生长，形态与 A₁ 组相似，生长趋势较好。同种异体动物体内实验显示，B₂ 组材料的排斥反应显著低于 A₂ 组；术后各时间点 A₂ 组的 IgM 和 IgG 含量均显著高于 B₂ 组（P<0.05）；HE 染色示，B₂ 组未见炎性细胞深层渗透或破坏气管结构，未见钙化、排斥等不良反应。 结论经 NaClO₄ 化学脱细胞处理后，兔气管支架材料具有良好的生物相容性，同时其免疫原性降低，适合作为构建组织工程气管的支架材料。