Innate immunity in Caenorhabditis elegans is regulated by neurons expressing NPR-1/GPCR

A large body of evidence indicates that metazoan innate immunity is regulated by the nervous system, but the mechanisms involved in the process and the biological importance of such control remain unclear. We show that a neural circuit involving npr-1, which encodes a G protein-coupled receptor (GPCR) related to mammalian neuropeptide Y receptors, functions to suppress innate immune responses. The immune inhibitory function requires a guanosine 3',5'-monophosphate-gated ion channel encoded by tax-2 and tax-4 as well as the soluble guanylate cyclase GCY-35. Furthermore, we show that npr-1- and gcy-35-expressing sensory neurons actively suppress immune responses of nonneuronal tissues. A full-genome microarray analysis on animals with altered neural function due to mutation in npr-1 shows an enrichment in genes that are markers of innate immune responses, including those regulated by a conserved PMK-1/p38 mitogen-activated protein kinase signaling pathway. These results present evidence that neurons directly control innate immunity in C. elegans, suggesting that GPCRs may participate in neural circuits that receive inputs from either pathogens or infected sites and integrate them to coordinate appropriate immune responses.     

流式细胞仪分析法检测黑熊成纤维细胞周期同步化处理效果

分离培养黑熊皮肤成纤维细胞 ,传 3代 ,分别经血清饥饿 2～ 6 d和 10 g/ L Nocodazole处理 2 4 h后 ,用流式细胞仪分析 2个处理组和对照组细胞的周期相 ,以研究黑熊成纤维细胞同步化处理后的细胞周期时相的变化 ,探讨核移植供体细胞的细胞周期对核移植胚胎发育的影响。结果显示 ,血清饥饿组、Nocodazole处理组及对照组的 G0 +G1 期成纤维细胞的百分率分别为 (85 .0 5± 7.0 0 ) % ,(4 5 .9± 3.7) %和 (5 9.3± 6 .7) % ;G2 / M期细胞的百分率分别为 (10 .4± 6 .8) % ,(4 6 .3± 4 .2 ) %及 (2 3.0 5± 1.0 5 ) %。表明血清饥饿法能较好地使黑熊成纤维细胞同步于 G0 和 G1 期 ;Nocodazole处理可以使细胞较大程度同步于 G2 和 M期。     

Extrafollicular activation of lymph node B cells by antigen-bearing dendritic cells

In contrast to na?ve T cells that recognize short antigen-derived peptides displayed by specialized antigen-presenting cells, immunoglobulin receptors of B lymphocytes primarily recognize intact proteins. How and where within a lymph node such unprocessed antigens become available for na?ve B cell recognition is not clear. We used two-photon intravital imaging to show that, after exiting high-endothelial venules and before entry into lymph node follicles, B cells survey locally concentrated dendritic cells. Engagement of the B cell receptor by the dendritic cell (DC)-associated antigen leads to lymphocyte calcium signaling, migration arrest, antigen acquisition, and extrafollicular accumulation. These findings suggest a possible role for antigen-specific B-DC interactions in promoting T cell-dependent antibody responses in vivo.     

Epidermal viral immunity induced by CD8alpha+ dendritic cells but not by Langerhans cells

The classical paradigm for dendritic cell function derives from the study of Langerhans cells, which predominate within skin epidermis. After an encounter with foreign agents, Langerhans cells are thought to migrate to draining lymph nodes, where they initiate T cell priming. Contrary to this, we show here that infection of murine epidermis by herpes simplex virus did not result in the priming of virus-specific cytotoxic T lymphocytes by Langerhans cells. Rather, the priming response required a distinct CD8alpha+ dendritic cell subset. Thus, the traditional view of Langerhans cells in epidermal immunity needs to be revisited to accommodate a requirement for other dendritic cells in this response.     

Suppression of macrophage activation and T-lymphocyte function in hypoprolactinemic mice

The effects of prolactin on lactation and reproductive organs are well known. However, the other possible target organs and physiological consequences of altered levels of circulating prolactin remain poorly understood. In this study, mice were treated with bromocryptine, a dopamine receptor agonist that inhibits pituitary prolactin secretion. Bromocryptine treatment prevented T-cell-dependent induction of macrophage tumoricidal activity after the intraperitoneal injection of Listeria monocytogenes or Mycobacterium bovis. Coincident treatment with ovine prolactin reversed this effect. Of the multiple events leading to macrophage activation in vivo, the production by T-lymphocytes of gamma-interferon was the most impaired in bromocryptine-treated mice. Lymphocyte proliferation after stimulation with mitogens in vitro was also depressed in spleens of bromocryptine-treated mice, and coadministration of prolactin also reversed this effect. Bromocryptine treatment also reduced the number of deaths resulting from inoculation of mice with Listeria; exogenous prolactin significantly reversed this effect. The critical influence of pituitary prolactin release on maintenance of lymphocyte function and on lymphokine-dependent macrophage activation suggests that, in mice, lymphocytes are an important target tissue for circulating prolactin.     

脂质体LTX介导高效转染山羊胎儿成纤维细胞(gFFCs)条件的优化

探讨获得外源基因高效转染山羊胎儿成纤维细胞(gFFCs)的方法,为筛选出体细胞核移植的供核细胞,制备转基因山羊提供技术基础。该研究以绿色荧光蛋白基因(GFP)为报告基因,采用脂质体LipofectaminTM LTX+PLUSTMReagent介导,对细胞接种量、质粒DNA用量、脂质体与质粒DNA比例、脂质体-DNA复合物与细胞作用时间进行优化,荧光显微镜下统计转染后24h的转染效率。结果显示：在24孔培养板中,每孔接种细胞6×104个,24h后进行转染,质粒DNA每孔0.6μg,脂质体与质粒DNA比例为4.5：1.0,脂质体-DNA复合物与细胞作用时间为6 h时,转染效率最高,达到81.2％。     

山羊ESC培养上清液对PBMC和PBL转化及分泌活性的影响

【目的】探索山羊子宫内膜基质细胞(ESC)培养上清,对山羊外周血单核细胞(PBMC)和外周血淋巴细胞(PBL)的转化与分泌活性的影响。【方法】分离山羊PBMC和PBL,制备原代ESC(ESC0)及永生化传至30代的ESC(ESC30)培养上清,将不同培养上清与PHA组合刺激PBMC与PBL转化,应用MTT法检测ESC0及ESC30培养上清对PBMC和PBL转化的作用,ELISA检测PBMC和PBL分泌IL-2I、L-4的相对含量。【结果】ESC0及ESC30上清可刺激PBMC/PBL转化并分泌IL-2和IL-4,抑制PHA-P诱导的PBMC/PBL增殖及IL-2的分泌,但对PHA-P引起的PBMC/PBL分泌IL-4有促进或协同作用。【结论】ESC能通过旁分泌作用影响PBMC和PBL的转化与分泌活性,优势活化Th2型淋巴细胞,在子宫局部免疫调节中发挥重要作用。     

Coordination of early protective immunity to viral infection by regulatory T cells

Suppression of immune responses by regulatory T cells (Tregs) is thought to limit late stages of pathogen-specific immunity as a means of minimizing associated tissue damage. We examined a role for Tregs during mucosal herpes simplex virus infection in mice, and observed an accelerated fatal infection with increased viral loads in the mucosa and central nervous system after ablation of Tregs. Although augmented interferon production was detected in the draining lymph nodes (dLNs) in Treg-deprived mice, it was profoundly reduced at the infection site. This was associated with a delay in the arrival of natural killer cells, dendritic cells, and T cells to the site of infection and a sharp increase in proinflammatory chemokine levels in the dLNs. Our results suggest that Tregs facilitate early protective responses to local viral infection by allowing a timely entry of immune cells into infected tissue.     

Adenyl cyclase of cultured mammalian cells: activation by catecholamines

Chang's liver cells and 3T6 mouse embryo fibroblasts contain high amounts of catecholamine-sensitive adenyl cyclase, whereas HeLa cells contain relatively low amounts of activity. Both epinephrine and fluoride ion stimulate activity of each cell line. In contrast to normal liver, Chang's liver cells show greater response to epinephrine and no detectable stimulation by glucagon.     

Suppression of pain by sound

A procedure involving music and noise has been effective in suppressing pain in 5000 dental operations. The music promotes relaxation, and the noise (the main agent) directly suppresses pain. The dental procedure and results are described, and an explanatory hypothesis is suggested.     

山羊成纤维细胞体外培养研究

分别采用组织块法与消化法对山羊耳成纤维细胞进行原代培养,比较两种方法的培养效果.结果表明,组织块法培养的细胞生长稳定,5～7d有细胞生长,15～18d长满单层;消化法培养的细胞,通过简化酶作用时间及用量的调控,可得到较为单一的成纤维细胞,且经过4～7d生长后能形成单层.同时对细胞培养过程中常遇到的污染问题及解决方法进行了探讨,为动物组织培养研究提供了实验依据.     

Suppression of the neoplastic phenotype by replacement of the RB gene in human cancer cells

Mutational inactivation of the retinoblastoma susceptibility (RB) gene has been proposed as a crucial step in the formation of retinoblastoma and other types of human cancer. This hypothesis was tested by introducing, via retroviral-mediated gene transfer, a cloned RB gene into retinoblastoma or osteosarcoma cells that had inactivated endogenous RB genes. Expression of the exogenous RB gene affected cell morphology, growth rate, soft agar colony formation, and tumorigenicity in nude mice. This demonstration of suppression of the neoplastic phenotype by a single gene provides direct evidence for an essential role of the RB gene in tumorigenesis.     

Toll-like receptor 4-dependent activation of dendritic cells by beta-defensin 2

beta-Defensins are small antimicrobial peptides of the innate immune system produced in response to microbial infection of mucosal tissue and skin. We demonstrate that murine beta-defensin 2 (mDF2beta) acts directly on immature dendritic cells as an endogenous ligand for Toll-like receptor 4 (TLR-4), inducing up-regulation of costimulatory molecules and dendritic cell maturation. These events, in turn, trigger robust, type 1 polarized adaptive immune responses in vivo, suggesting that mDF2beta may play an important role in immunosurveillance against pathogens and, possibly, self antigens or tumor antigens.     

TLR11 activation of dendritic cells by a protozoan profilin-like protein

Mammalian Toll-like receptors (TLRs) play an important role in the innate recognition of pathogens by dendritic cells (DCs). Although TLRs are clearly involved in the detection of bacteria and viruses, relatively little is known about their function in the innate response to eukaryotic microorganisms. Here we identify a profilin-like molecule from the protozoan parasite Toxoplasma gondii that generates a potent interleukin-12 (IL-12) response in murine DCs that is dependent on myeloid differentiation factor 88. T. gondii profilin activates DCs through TLR11 and is the first chemically defined ligand for this TLR. Moreover, TLR11 is required in vivo for parasite-induced IL-12 production and optimal resistance to infection, thereby establishing a role for the receptor in host recognition of protozoan pathogens.     

食蟹猴耳部成纤维细胞体外培养体系的初步建立

建立食蟹猴耳部成纤维细胞的体外培养体系,为食蟹猴体细胞核移植、转基因技术及治疗性克隆做准备.通过组织块培养法进行原代培养,成功分离了食蟹猴耳部成纤维细胞;原代培养后用0.25%胰蛋白酶+0.02%EDTA消化液消化细胞,用含10%FBS的DMEM对细胞进行培养,细胞在体外传至第25代;用含10%FBS和10%DMSO的DMEM为冷冻液对细胞进行冷冻保存,解冻传代后,细胞形态和生长速度没有明显变化;用细胞技术法绘制细胞的生长曲线显示,符合体外细胞生长规律;用吉姆萨染色法对不同代数细胞的染色体倍性进行分析,二倍体细胞所占比例为80%以上.     

Maintenance of serological memory by polyclonal activation of human memory B cells

Production of antibodies can last for a lifetime, through mechanisms that remain poorly understood. Here, we show that human memory B lymphocytes proliferate and differentiate into plasma cells in response to polyclonal stimuli, such as bystander T cell help and CpG DNA. Furthermore, plasma cells secreting antibodies to recall antigens are produced in vivo at levels proportional to the frequency of specific memory B cells, even several years after antigenic stimulation. Although antigen boosting leads to a transient increase in specific antibody levels, ongoing polyclonal activation of memory B cells offers a means to maintain serological memory for a human lifetime.     

山羊子宫内膜基质细胞的分离培养及鉴定

对山羊子宫内膜基质细胞进行分离与体外培养,研究其生长特性,并对其进行免疫细胞化学染色鉴定。结果表明,山羊子宫内膜在37℃条件下,以2 g／L的胶原酶Ⅰ型消化3～4 h效果最好;采用过滤—低速离心—沉降相结合的方法分离山羊子宫内膜基质细胞效果较好,所得细胞在培养后0．5 h开始贴壁,培养12 h后,可见梭形和多角形2种形态的细胞,3～4 d呈网状铺满皿底,有明显的重叠生长现象;免疫细胞化学染色显示这2种形态的细胞均表达波形蛋白,阳性率可达95％以上,不表达角蛋白。说明采用本文所述的消化和分离方法可获得高纯度的子宫内膜基质细胞。     

Survival for immunity: the price of immune system activation for bumblebee workers

Parasites do not always harm their hosts because the immune system keeps an infection at bay. Ironically, the cost of using immune defenses could itself reduce host fitness. This indirect cost of parasitism is often not visible because of compensatory resource intake. Here, workers of the bumblebee, Bombus terrestris, were challenged with lipopolysaccharides and micro-latex beads to induce their immune system under starvation (i.e., not allowing compensatory intake). Compared with controls, survival of induced workers was significantly reduced (by 50 to 70%).