Alpha-momorcharin inhibits HIV-1 replication in acutely but not chronically infected T-lymphocytes

AIM: To identify the anti-human immunodeficiency virus type 1 (HIV-1) activities of alpha-momorcharin ( alpha-MMC) from Momordica charantia in acutely and chronically infected lymphocytes. METHODS: The anti-HIV activities of alpha-MMC were examined by 1) the inhibition of syncytia formation induced by HIV-1 III B; 2) reduction of p24 core antigen expression level and decrease in numbers of HIV antigen positive cells in acutely and chronically infected cultures. The cytotoxic effects of alpha-MMC was tested by trypan blue dye exclusion or colorimetric MTT assay. RESULTS: alpha-MMC was found to obviously inhibit HIV-1 III B-inducing C8166 syncytia formation and markedly reduced both expression of p24 core antigen and the numbers of HIV antigen positive cells in acutely but not chronically HTV-1-infected culture. The median effective concentration (EC50) in these assays were 0.016, 0.07, and 0.32 mg.L-1, respectively. CONCLUSION: alpha-MMC is a unique component of momorcharin with anti-HIV activity, and markedly inhibited HIV-1 replication in acutely but not chronically HIV-1-infected T-lymphocytes.

动物模型在HIV-1杀微生物剂有效性和安全性评价中的应用

HIV/AIDS的流行趋势没有减弱的迹象,人们迫切需要新的预防HIV传播的手段。杀微生物剂旨在通过局部用药于阴道或直肠,从而阻止HIV的传播。鉴于目前有大量的杀微生物剂候选物,亟待能够有效评价其有效性及安全性的动物模型。通过比较非灵长类小型动物模型与非人灵长类动物模型在评价HIV杀微生物剂的有效性及安全性上的重要作用,该文总结了评价杀微生物剂有效性及安全性的动物模型的优缺点,同时指出了杀微生物剂研究与发展的方向和建议,希望能够对杀微生物剂的研发有所帮助。

HIV-1感染对T和B细胞核内UNG2 mRNA表达的影响

目的:探讨HIV-1感染是否影响细胞中UNG2的表达.方法:采用四步法SYBR green Ⅰ实时定量RT-PCR,对HIV-1感染者的T和B淋巴细胞,以及HIV-1感染的C8166细胞核内UNG2 mRNA的表达进行测定.结果:UNG2 mRNA的表达在HIV-1感染者的T细胞和HIV-1感染的C8166细胞中被明显上调,分别是对照的8.76倍和8.14倍,而在HIV-1感染者的B细胞中却没有被上调.结论:HIV-1感染导致的UNG2表达上调,可能通过减少TCR的多样性削弱Th的功能,另一方面可能有利于病毒对UNG2的包装.

与植物多糖硫酸酯结合的HIV-1ⅢB灭活病毒免疫小鼠的研究

目的：为了探讨植物多糖硫酸酯（’&&(）与)*+%$ 结合后，能否诱导,-./+#0 的)*+%$ 暴露出中和抗体的表 位，用它作为灭活疫苗以便诱导产生中和抗体。方法：用’&&( 结合的灭活,-./+#0 作为免疫原，与佐剂混和后，免疫 0(102 3 小鼠，制备出免疫血浆。用41-5( 检测血浆内抗,-./+ 特异性-)6 抗体的滴度，用改良的活细胞染色法中和试验检测 免疫血浆的抗,-./+#0 的中和活性。结果：从与’&&( 结合的,-./+#0 免疫组的动物获得的免疫血浆内抗,-./+ 抗体的滴 度（7 组：+8 # 9 +$" ；: 组：+8 # 9 +$" ）比未结合’&&( 的,-./+#0 免疫组（;8 < 9 +$# ）高，雌性小鼠的免疫血浆的特异性抗体滴 度比雄性的高& 倍。所有免疫组获得的免疫血浆均没有抗,-./+ 中和活性。结论：’&&( 与)*+%$ 相互作用不能诱导暴露出 )*+%$ 的中和抗体表位，但’&&( 可以增强机体免疫原的抗体反应强度，提示它可以作为免疫增强剂用于疫苗研究。

检测HIV-1载量的荧光实时定量PCR技术的建立及其应用

其它部委、高等院校基金;中国科学院基金

Interaction between human interleukin-16 and CD4 receptor of HIV-1

AIM: To study the interaction between human interleukin-16 (IL-16) and the receptor CD4 (T-lymphocyte differentiation antigen) of human immunodeficiency virus type 1 (HIV-1). METHODS: Two structurally con served regions (SCRs) of human IL-16 were built by the SYBYL/Biopolymer module using the corresponding transmembrane (TM) domain of human interleukin-1 (HIL-4) and HIL-2 as the templates. The coordinates for amino-terminal residue sequence, carboxyl-terminal residue sequences, and cytoplasm loops were generated using Biopolymer's LOOP SEARCH algorithm. RESULTS: HIL-16 first formed a homodimer, then contacted with CD4 dimer further forming a dimeric complex. Subsequently, the dimeric complex constructed the tetrameric complex by two disulfide bridges between the cysteines of HIL-16 (Cys31-Cys31). CONCLUSION: The interaction model is useful to propose the action mechanism of HIL-16 and is beneficial for rational designing of novel anti-HIV drugs.

Molecular modeling on human CCR5 receptors and complex with CD4 antigens and HIV-1 envelope glycoprotein gp120

AIM: To investigate the interaction between human CCR5 receptors (CCR5) and HIV-1 envelope glycoprotein gp120 (HIV-1 gp120) and HIV-1 receptor CD4 antigens (CD4). METHODS: The structurally con served regions (SCR) of human CCR5 was built by the SYBYL/Biopolymer module using the corresponding transmembrane (TM) domain of bacteriorhodopsin (bR) as the template. The coordinates for amino-ter minal residue sequence, and carboxyl-terminal residue sequence, extracellular and cytoplasmic loops were generated using LOOP SEARCH algorithm. Subsequently the structural model was merged into the complex with HIV-1 gp120 and CD4. RESULTS: Human CCR5 interacted with both an HIV-1 gp120 and CD4. The N-terminal residues (especially Met1 and Gln4) of human CCR5, contacted with CD4 residues, mainly 7Nith one span (56 - 59) of CD4 in electrostatic interaction and hydrogen-bonds. The binding sites of human CCR5 were buried in a hydrophobic center surrounded by a highly basic periphery. On the other hand, direct interatomic contacts were made between ? CCR5 residues and 6 gp120 amino-acid residues, which included van der Waals contacts, hydrophobic interaction, and hydrogen bonds. CONCLUSION: The interaction model should be helpful for rational design of novel anti-HIV drugs.

On-going generation of multiple forms of HIV-1 intersubtype recombinants in the Yunnan Province of China

Objectives: To investigate the molecular epidemiology of HIV in China's Yunnan Province, where the initial HIV-1 outbreak among injecting drug users (IDU) occurred in 1989, and to analyse the genesis and interrelationship of the epidemic with that in surrounding areas. Design: A molecular epidemiological investigation was conducted among IDU in three prefectures in Yunnan Province, including Wenshan (east), Honghe (southeast) and Dehong (west). Methods: Thirty-nine specimens were collected from consenting IDU in 2000-2001. The nucleotide sequences of 2.6 kb gag-RT and 340 base pair (bp) env (C2/V3) regions were determined. Phylogenetic tree and recombination breakpoint analyses were performed. Results: The circulating recombinant form (CRF), CRF08_BC, predominated in east Yunnan near Guangxi Province (89% in Wenshan and 81% in Honghe), whereas it was not detected in Dehong(0/14) in the west. In contrast, 71% (10/14) of the Dehong isolates were unique recombinant forms (URF), mostly between subtypes B' (Thailand variant of subtype B) and C, with distinct profiles of recombination breakpoints. The subtype B' accounts for the remaining 29% (4/14) of Dehong isolates. Interestingly, two Honghe isolates (2/16) shared some of the precise B'/C recombination breakpoints with CRF07_BC. Conclusion: New recombinant strains are arising continually in west Yunnan near the Myanmar border. Some appeared to be secondary recombinants derived from CRF07_BC that had further recombined with other strains. The uneven distribution of subtypes, CRF and URF, suggests the presence of independent transmission networks and clusters among IDU in Yunnan. (C) 2002 Lippincott Williams Wilkins.

Molecular epidemiology of the heterosexual HIV-1 transmission in Kunming, Yunnan Province of China suggests origin from the local IDU epidemic

Molecular epidemiological investigation was conducted among injecting drug users (IDUs) (n = 11) and heterosexuals (n = 15) in Kunming, Yunnan Province of China. HIV-1 genotypes were determined based on the nucleotide sequences of 2.6-kb gag-RT region. The distribution of genotypes among IDUs was as follows: CRF07_BC (5/11) and CRF08_BC (5/11); subtype B' (1/11). Similarly, a majority of Kunming heterosexuals (14/15) were infected with CRF07_BC (4/15), CRF08_BC (6/15), or subtype B' (4/15), known to predominate among IDUs in China. This contrasts with trends in the coastal regions of China and surrounding southeastern Asian countries, where CRF01_AE predominates among heterosexuals. The heterosexual HIV-1 epidemic in Kunming thus appears to derive from the local IDU epidemic. Of note, subtype B' was the most prevalent strain among heterosexuals before 1997, while CRF07_BC and CRF08_BC became predominant in 2002, indicating a transition of HIV-1 genotype distribution between the early and the more recent samples from Kunming heterosexuals.

HIV-1 C亚型密码子优化gp120负载人DC疫苗的构建及体外功能

目的构建HIV-1C亚型gp120负载人树突状细胞(dentriti ccell,DC)疫苗,并对其体外功能进行初步检测。方法利用Amaxa细胞核转染技术将pcDNA3.1-gp120质粒转染至人成熟DC,以Western blot检测gp120的表达。通过流式细胞仪检测DC表面共刺激分子的变化、混合淋巴细胞反应、CD8+T细胞表面活化分子CD25的表达及其分泌IFN-γ的变化。结果通过Western blot检测,gp120在DC中得到了正确表达。经流式细胞仪检测,DC表面分子CD80表达率由刺激前的33.34%上升至43.20%,CD86表达率由刺激前的60.08%上升至90.34%;负载gp120DC刺激淋巴细胞增殖率为86.72%;CD8+T细胞表面分子CD25表达率由刺激前的5.27%上升至74.21%,IFN-γ的表达率达37%。结论负载了HIV-1gp120的人树突状细胞能够显著刺激淋巴细胞的增殖、增强CD8+T细胞表面活化分子CD25表达以及促进CD8+T细胞分泌IFN-γ,为下一步DC治疗性疫苗的体内研究奠定基础。

基于Vif-APOBEC3G相互作用的抗HIV-1药物研究

载脂蛋白B mRNA编辑酶催化多肽样蛋白3G(apolipoprotein B mRNA-editing enzyme catalyticpolypeptidelike3G,APOBEC3G或A3G)是人体天然抗病毒分子,可以使病毒逆转录形成的cDNA的胞嘧啶(C)脱氨为尿嘧啶(U),产生鸟嘌呤(G)→腺嘌呤(A)超突变,导致病毒转录产物突变,从而达到抑制病毒复制的作用。HIV-1的辅助蛋白Vif,可与APOBEC3G相互作用并导致其被降解,使得这一天然抗病毒机制失效,进而增强了HIV的感染力。Vif与APOBEC3G这种相互作用为抗HIV药物提供了新靶点。针对Vif-APOBEC3G相互作用的抗HIV抑制剂已经成为研究热点。本文综述了Vif和APOBEC3G的结构、二者的相互作用,以及基于这一相互作用的抗HIV-1抑制剂研究进展。

天花粉蛋白抗HIV．1构效关系及机制探讨

目的研究TCS抗HIV-1的构效关系并对机制进行探讨。方法蛋白工程技术构建14个TCS突变 体，测定各种TCS突变体的细胞毒性和抗HIV恬性。结果活性中心突变体TCSM(120—123)与TcSEl60A／E189A在失 去绝大部分RI活性的同时，也几乎完全失去抗HIV活性。而另一个活性中心突变体TCSRl22G，RI活性下降160 倍，却仍保留一定的抗HIV活性。TCSC末端删除突变体(TCS(2，TCSo和TCScl。)抗HIV活性的下降(1．4—4．8 倍)与其RI活性呈平行下降(1．2—3．3倍)；分别在C末端加上末端19个氨基酸延伸肽或KDEL信号肽的突变体 TCscl9。与TQkDEL，虽然保留全部的RI活性，但却几乎完全失去抗HIV活性；TCS抗原决定簇位点突变后对TCS 抗HIV．1括性没有显著影响，但当在抗原决定簇突变体所引入的Cys残基上加上PEG20K后，这些突变体则显著降 低了抗HIV-1的活性。TCS不能抑制HIV一1进入宿主细胞；对感染细胞和未感染细胞的融合没有抑制作用；TCS 也不能抑制HIV一1 rRT活性；TCS对病毒颗粒的直接杀伤作用不大。结论TCS抗HIV-1活性与其Rl活性显著 相关，但似乎又不是唯一的决定因素；TCS C末端氨基酸的突变影响其抗HIV．1活性；在C末端增加KDEL信号肽 序列及19aa尾肽并不能增加其抗HIV活性；抗原决定簇突变体以及PEG20K偶联TCS抗原决定簇突变体体外抗 HIV-1活性下降；抗HIV．1机制可能与对感染细胞的间接作用有关。

APOBEC3G抗HIV一1作用机制研究进展

】APOBEC3G是细胞内新的广谱抗病毒蛋白。它具有胞苷脱氨酶活性，能使病毒负链 DNA产生dC--·dU高发突变，造成正链DNA G---A突变，使得病毒DNA变成无功能或降解。APO— BEC3G具有广泛的生物学功能，可以限制HIV-1等病毒复制，但HIV-1病毒感染因子Vii能拮抗 APOBEC3G抑制病毒活性作用。本文简要综述了APOBEC3G抑制病毒HIV-1作用机制的最新进 展。