Heterologous structure of coating antigen on sensitivity of ELISA for sulfamethazine: evidence from molecular similarity analysis

Six structurally similar sulfonamide haptens have been linked to ovalbumin by diazo-method used as coating antigen. An enzyme-linked immunosorbent assay (ELISA) was developed to investigate heterologous structure of coating haptens on sensitivity of ELISA for sulfamethazine. The sensitivities of ELISA, expressed as IC₅₀ values, ranged from 94 to 877 ng mL^{? 1} when six coating antigens were employed. The results suggested that the structural heterology of coating hapten had significant effect on ELISA sensitivity. In order to evaluate the relationship between the degree of hapten heterology and ELISA sensitivity, we used molecular similarity methods to qualitatively represent the degree of coating hapten heterology. The Molecular Access System (MACCS) structural keys and the Tanimoto similarity coefficient were used to calculate and compare the degree of coating hapten's similarity, and the authors found that the sensitivity of ELISA was not in direct proportion with degree of coating hapten heterology in the case of study.     

考虑热量和压力功影响的氢网络扩展矩阵法

以解藻酸弧菌株（Vibrio alginolyticus）ATCC 17749为研究对象,利用生物信息学寻找并预测得到5个可能的海藻酸裂解酶基因algV1、 algV2、 algV3、 algV4和 algV5。通过构建5个以pET 28a(+)为载体的大肠杆菌表达质粒pET28a algV1、pET28a algV2、pET28a algV3、pET28a algV4和pET28a algV5,实现了5个基因的异源表达,并经海藻酸裂解酶定量和定性的活性分析,确定5个基因的编码产物都具有海藻酸裂解酶活性,其中重组的algV1、 algV2和 algV3为胞外酶,algV4和algV5为胞内酶。     

成人睾丸组织在裸鼠体内的存活情况研究

目的以成人睾丸组织为供体,免疫缺陷小鼠为受体,研究成人睾丸组织中生精细胞异种移植后的存活及变化情况。方法将成人正常睾丸组织植入去势裸鼠背部,于移植后110d取出移植物,进行组织形态学观察。结果在一例移植前显示非正常生精上皮结构标本的移植物中,大多数生精小管中只含有Sertoli细胞,而另一例移植前显示出正常生精上皮结构的标本,在移植到裸鼠背部110d后,仍然观察到圆形和长形精子细胞存在。结论将成人睾丸组织移植到免疫缺陷小鼠体内,110d后仍观察到有生精细胞的存活。     

微囊化异种甲状旁腺组织移植的研究

目的探讨微囊化异种甲状旁腺(PTG)组织移植对Wistar大鼠甲状旁腺功能低下的治疗作用及微囊的通透性。方法 40只去甲状旁腺Wistar大鼠随机分为微囊组、非微囊组、空囊组、空白对照组。用海藻酸-钡交联微囊包裹兔甲状旁腺组织,移植至Wistar大鼠肾包囊。移植后每隔2周取血测血钙,移植后第16周取移植物进行透射电镜检查及T淋巴细胞、大鼠IgG抗体的免疫组织化学染色。结果微囊组移植后第4周血清钙由(1．62±0．04)mmol／L恢复至正常水平 (2．2～2．6)mmol／L,9例维持至观察期结束(P<0．01),非微囊组、空囊组及空白对照组血清钙差异无统计学意义(P>0．05)。第16周取出移植物检测显示移植物活性良好,微囊周围可见较多T 淋巴细胞浸润,囊壁及囊内IgG抗体染色阳性。结论海藻酸-钡交联微囊可对甲状旁腺组织起到有效的保护作用,使甲状旁腺组织较长时间存活并发挥正常功能。但海藻酸-钡交联微囊并未减轻受体免疫排斥反应的激活且未有效的免疫隔离IgG抗体。     

三种移植骨材料修复骨缺损能力的比较研究

目的 研究单纯异种无机骨，复合骨髓异种无机骨以及自体皮质骨修复骨缺损的能力。方法 取健康6月龄纯系新西兰大白兔22只，制作兔桡骨节段性骨缺损（1.5cm)模型。根据植入物的不同，随机分为自体皮质骨组（10肢），单纯异种无机骨组（10肢），复合骨髓的异种无机骨组（20肢）和空白对照组（4肢），术后2、4、6、8、12周进行放射线片和组织学观察。结果 单纯异种无机骨植入组，直至12周，仍为缓慢的骨传导过程，周边骨小梁向无机骨内爬行替代，异种无机骨内大部分为纤维组织，只有少数中心区域有新骨形成，而复合骨髓的异种无机骨植入后2周即有新骨形成，8周无机骨基本吸收替代完毕，12周髓腔形成，塑形改造，基本相关于自体皮质骨移植的融合速度，结论 复合骨髓的异种无机骨的成骨能力明显优于单纯异种无机骨，与自体皮质骨相当。     

Rat Cytomegalovirus Infection Interferes with Anti-CD4 mAb-(RIB 5/2) Mediated Tolerance and Induces Chronic Allograft Damage

In order to assess the role of heterologous immunity on tolerance induction (TI) by signal 1 modification, the influence of rat cytomegalovirus infection (RCMVI) on TI by a non-depleting monoclonal anti-CD4 mAb (monoclonal antibody) (RIB 5/2) in a rat kidney transplant (KTx) model was investigated. Orthotopic rat KTx (Dark Agouty (DA)-->Lewis (LEW)) was performed after TI with RIB 5/2 [10 mg/kg body weight (BW); day -1, 0, 1, 2, 3; i.p. (intraperitoneal route)]. RCMVI (5x10E5 Plaque forming units [PFU] i.p.) was simultaneously conducted to KTx, 50 days after KTx, and 14 days before and after KTx. RIB 5/2 induced robust allograft tolerance even across the high-responder strain barrier. RCMVI broke RIB 5/2-induced tolerance regardless of the time of RCMVI but did not induce acute graft failure during the 120 days follow-up. RCMVI induced a significant chronic deterioration of allograft function (p<0.01) and enhanced morphological signs of chronic allograft damage (p<0.05). Cellular infiltrates and major histo-compatibility complex (MHC)-expression were more pronounced (p<0.05) in the infected groups. RCMVI induced not only RCMV-specific T-cell response but also enhanced the frequency of alloreactive T cells. RCMV interferes with anti-CD4 mAb-induced tolerance and leads to chronic allograft damage. The data we presented suggest a potentially important role of viral infections and their prophylaxis in clinical TI protocols.     

微囊化人嗜铬细胞对大鼠异种移植的免疫隔离作用

目的探讨微囊化人嗜铬细胞(ME-HCC)移植于大鼠眼前房或足胝部的免疫隔离作用。方法雌性SD大鼠48只,3月龄,体重180-250g。随机分为3组,HCC组、空微囊组、ME-HCC组,每组16只。HCC组、空微囊组、ME-HCC组分别将HCC、空微囊、ME-HCC移植于大鼠的眼前房(n=8)或足胝部(n=8)。移植术后7d大鼠断尾取血,测定白细胞介素-2(IL-2)、IgG和IgM浓度。移植术后28d 处死大鼠,光镜下观察右侧眼球或左侧足组织形态学变化。结果与HCC组比较,空微囊组和ME- HCC组大鼠血清IL-2、IgG、IgM浓度均降低(P<0.01);ME-HCC、空微囊组血清IL-2、IgG、IgM浓度比较差异无统计学意义(P>0.05)。HCC组大鼠眼前房和足胝部可见大量淋巴细胞和中性粒细胞浸润。空微囊组、ME-HCC组大鼠眼前房和足胝部仅见少量淋巴细胞和中性粒细胞。结论微囊化人HCC 对大鼠异种移植的免疫排斥具有隔离作用。     

SURAMIN ACTIVIY IN HUMAN HEAD AND NECK SQUAMOUS CELL CARCINOMA——Ⅱ.EFFECT OF SURAMIN ON HUMAN HEAD AND NECK CARCINOMA XENOGRAFTS AND RELATED TOXICITY AND PHARMACOKINETIC STUDIES IN NUDE MICE

In part Ⅰ of the study,we have demonstrated that suraminhas a marked antiproliferative effect on human head and neck squamous cellcarcinoma cell lines,In the present study,both toxicity and pharmacokineticstudies in nude mice were done.The treatment of nude mice bearing head andneck cancers with suramin showed that suramin had a minimal antitumor effect.The possible mechanism of suramin lacking antitumor effect is discussed.     

Intranasal vaccination with influenza HA/GO-PEI nanoparticles provides immune protection against homo- and heterologous strains

Intranasal (i.n.) immunization is a promising vaccination route for infectious respiratory diseases such as influenza. Recombinant protein vaccines can overcome the safety concerns and long production phase of virus-based influenza vaccines. However, soluble protein vaccines are poorly immunogenic if administered by an i.n. route. Here, we report that polyethyleneimine-functionalized graphene oxide nanoparticles (GP nanoparticles) showed high antigen-loading capacities and superior immunoenhancing properties. Via a facile electrostatic adsorption approach, influenza hemagglutinin (HA) was incorporated into GP nanoparticles and maintained structural integrity and antigenicity. The resulting GP nanoparticles enhanced antigen internalization and promoted inflammatory cytokine production and JAWS II dendritic cell maturation. Compared with soluble HA, GP nanoparticle formulations induced significantly enhanced and cross-reactive immune responses at both systemic sites and mucosal surfaces in mice after i.n. immunization. In the absence of any additional adjuvant, the GP nanoparticle significantly boosted antigen-specific humoral and cellular immune responses, comparable to the acknowledged potent mucosal immunomodulator CpG. The robust immune responses conferred immune protection against challenges by homologous and heterologous viruses. Additionally, the solid self-adjuvant effect of GP nanoparticles may mask the role of CpG when coincorporated. In the absence of currently approved mucosal adjuvants, GP nanoparticles can be developed into potent i.n. influenza vaccines, providing broad protection. With versatility and flexibility, the GP nanoplatform can be easily adapted for constructing mucosal vaccines for different respiratory pathogens.

Influenza remains one of the leading infectious diseases causing morbidity and mortality worldwide. Vaccination is the most cost-effective approach to preventing influenza virus infection. However, current virus-based seasonal influenza vaccines induce strain-specific immunity and are less effective against mismatched strains that may cause influenza epidemics (1). Furthermore, there is no vaccine countermeasure available for new pandemic strains. Intranasal (i.n.) immunization is a promising vaccination route for infectious respiratory diseases, such as influenza. This vaccination route can induce both systemic and mucosal immune responses. Secretory immunoglobulin A (sIgA) and immunoglobulin G (IgG) may prevent influenza infection at the portal of virus entry. Influenza mucosal immunity has been reported to confer cross-protection against heterologous and heterosubtypic viruses (2). Moreover, needle-free i.n. influenza vaccines possess superior logistical advantages over traditional injectable vaccines, such as easy administration with high acceptance for recipients and avoidance of biohazardous sharps waste.However, the development of i.n. influenza vaccines has progressed slowly. The cold-adapted live-attenuated influenza virus (LAIV) vaccine is the only available human i.n. influenza vaccine up to date. Studies have shown that the LAIV vaccine could provide heterologous immunity (3). Nevertheless, safety concerns of LAIV are raised, especially in high-risk populations, such as infants under 2 y old and the elderly over 50. LAIV could undergo genetic reassortments and revert into a virulent form, thus posing a risk. Besides, the suboptimal protective efficacy of LAIV vaccines was reported in children in the 2009 H1N1 pandemic. A new generation of virus-independent, safe, and efficient influenza i.n. vaccines that induce broader cross-protection with high efficacy is urgently needed.Intranasal vaccination with recombinant protein/peptide-based vaccines is an attractive strategy with high safety (4). Purified protein/peptide antigens eliminate safety concerns in individuals with egg allergies, possess minimal side effects, and enable quick and cost-effective production. However, soluble protein vaccines are poorly immunogenic by i.n. immunization due to the harsh and tolerogenic mucosal environment (5). The selection of appropriate formulations and adjuvants is crucial for successful i.n. vaccines. Nanoparticle vaccine platforms have been applied for i.n. vaccine development in recent years (6, 7). Nanoparticles serve as antigen and adjuvant carriers and immunostimulants themselves to enhance immune responses. The immunoenhancing effects of various nanoparticles have been reported (8–13). However, most nanoparticle vaccines suffer from low antigen-loading capacity, complicated and lengthy preparation procedures, and structural complexity because of covalent conjugation.Two-dimensional (2D) graphene oxide (GO) nanoparticles have great potential as a novel vaccine platform due to their extraordinary attributes. These features include the high aspect ratio and ultra-large surface area for high-density antigen association, wealthy chemical groups for flexible surface modification and noncovalent antigen loading via electrostatic adsorption, hydrogen bond, and hydrophobic and π–π stacking interactions. Besides, GO nanoparticles themselves are biocompatible and nonimmunogenic (14, 15). Various GO vaccine formulations were demonstrated to induce improved immune responses by activating immune cells or triggering innate signaling (16–18). However, most prior studies were limited to conventional routes with tumor antigens for cancer immunotherapies. Studies on GO-based influenza i.n. vaccines are lacking.We developed a polyethyleneimine (PEI)-functionalized GO (GO-PEI, GP) influenza vaccine nanoplatform, prepared influenza GP nanoparticles by incorporating recombinant influenza hemagglutinin (HA) and investigated their immunoenhancing effects (Fig. 1). Our work revealed that influenza GP nanoparticles enhanced antigen internalization and promoted the production of inflammatory cytokines and the maturation of JAWS II dendritic cells (DCs) during in vitro experiments. i.n. vaccination with influenza GP nanoparticles induced robust humoral and cellular immune responses, conferring broader protection against challenges by homologous and heterologous influenza viruses in mice.Open in a separate windowFig. 1.Schematic illustration of the preparation and performance of influenza GP nanoparticles. (A) Preparation of GP and GP-HA/adjuvant nanoparticles. (B) Immunoenhancing effects of GP nanoparticle vaccines. GP nanoparticle vaccines showed enhanced cellular uptake in DCs and promoted inflammatory cytokine secretion and DC maturation. i.n. vaccination with influenza GP nanoparticles induced significantly enhanced and broad immune protection against homo- and heterologous influenza virus challenges. CTL, cytotoxic T lymphocyte; SR, survival rate.