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991.
人乳头瘤病毒可引起多种疾病,如寻常疣、扁平疣、尖锐湿疣、鲍恩样丘疹病、宫颈癌等.人乳头瘤病毒可以有效地逃逸固有免疫识别,其可能原因包括嗜上皮性、非溶解性复制、高免疫原性的衣壳蛋白在免疫活跃的复层鳞状上皮基底层呈低水平表达等.人乳头瘤病毒的致癌性以及所致疾病的临床高发病率受到人们的广泛关注.机体对抗人乳头瘤病毒的固有免疫已成为研究热点.概述多种皮肤免疫细胞,如角质形成细胞、树突细胞、朗格汉斯细胞、浆细胞样树突细胞、自然杀伤细胞和恒定型自然杀伤T细胞对人乳头瘤病毒固有免疫反应的相关研究. 相似文献
992.
993.
Papillomaviruses (PVs) are well established to cause hyperplastic papillomas (warts) in humans and animals. In addition, due to their ability to alter cell regulation, PVs are also recognized to cause approximately 5% of human cancers and these viruses have been associated with neoplasia in a number of animal species. In contrast to other domestic species, cats have traditionally been thought to less frequently develop disease due to PV infection. However, in the last 15 years, the number of viruses and the different lesions associated with PVs in cats have greatly expanded. In this review, the PV life cycle and the subsequent immune response is briefly discussed along with methods used to investigate a PV etiology of a lesion. The seven PV types that are currently known to infect cats are reviewed. The lesions that have been associated with PV infections in cats are then discussed and the review finishes with a brief discussion on the use of vaccines to prevent PV-induced disease in domestic cats. 相似文献
994.
Human papillomavirus type 159 (HPV159) was identified in an anal swab sample and preliminarily genetically characterized by our group in 2012. Here we present a detailed molecular in silico analysis that showed that the HPV159 viral genome is 7443 bp in length and divided into five early and two late genes, with conserved functional domains and motifs, and a non-coding long control region (LCR) with significant regulatory sequences that allow the virus to complete its life cycle and infect novel host cells. HPV159, clustering into the cutaneotropic Betapapillomavirus (Beta-PV) genus, is phylogenetically most similar to HPV9, forming an individual phylogenetic group in the viral species Beta-2. After testing a large representative collection of clinical samples with HPV159 type-specific RT-PCR, in addition to the anal canal from which the first HPV159 isolate was obtained, HPV159 was further detected in other muco-cutaneous (4/181, 2.2%), mucosal (22/764, 2.9%), and cutaneous (14/554, 2.5%) clinical samples, suggesting its extensive tissue tropism. However, because very low HPV159 viral loads were estimated in the majority of positive samples, it seemed that HPV159 mainly caused clinically insignificant infections of the skin and mucosa. Using newly developed, highly sensitive HPV159-specific nested PCRs, two additional HPV159 LCR viral variants were identified. Nevertheless, all HPV159 mutations were demonstrated outside important functional domains of the LCR, suggesting that the HPV159 viral variants were most probably not pathogenically different. This complete molecular characterization of HPV159 enhances our knowledge of the genome characteristics, tissue tropism, and phylogenetic diversity of Beta-PVs that infect humans. 相似文献
995.
K. Szarka I. Tar E. Fehér T. Gáll A. Kis E. D. Tóth R. Boda I. Márton L. Gergely 《Oral microbiology and immunology》2009,24(4):314-318
Introduction: We investigated the potential role of human papillomaviruses (HPVs) in potentially malignant oral disorders, oral leukoplakia (OL) and oral lichen planus (OLP), and in oral squamous cell cancer (OSCC) in an Eastern Hungarian population with a high incidence of OSCC.
Methods: Excised tumor samples (65 OSCC patients) and exfoliated cells from potentially malignant lesions (from 44 and 119 patients with OL and OLP, respectively) as well as from healthy controls (72 individuals) were analysed. OLPs were classified based on clinical appearance, 61 patients had erosive–atrophic lesions (associated with higher malignancy risk, EA-OLP) and 58 had non-erosive non-atrophic lesions (with lower risk of becoming malignant, non-EA-OLP), respectively. Exfoliated cells collected from apparently healthy mucosa accompanied each lesion sample. HPV was detected by MY/GP polymerase chain reaction (PCR) and genotyped by restriction analysis of amplimers. Copy numbers in lesions were determined using real-time PCR. Prevalence rates, copy number distributions, and association with risk factors and diseases were analysed using chi-square test, t -test, and logistic regression, respectively.
Results: We detected HPVs significantly more frequently in lesions than in controls ( P ≤ 0.001 in all comparisons). HPV prevalence increased gradually with increasing severity of lesions (32.8, 40.9, and 47.7% in OLP, OL, and OSCC, respectively). Copy number distribution patterns roughly corresponded to prevalence rates, but OLP and OL were comparable. HPV prevalence differed significantly between EA-OLP and non-EA-OLP groups (42.6 vs. 22.4%); EA-OLP group showed a prevalence similar to that found in OL.
Conclusion: HPVs may be involved in the development or progression of not only OSCC but also of potentially malignant oral lesions. 相似文献
Methods: Excised tumor samples (65 OSCC patients) and exfoliated cells from potentially malignant lesions (from 44 and 119 patients with OL and OLP, respectively) as well as from healthy controls (72 individuals) were analysed. OLPs were classified based on clinical appearance, 61 patients had erosive–atrophic lesions (associated with higher malignancy risk, EA-OLP) and 58 had non-erosive non-atrophic lesions (with lower risk of becoming malignant, non-EA-OLP), respectively. Exfoliated cells collected from apparently healthy mucosa accompanied each lesion sample. HPV was detected by MY/GP polymerase chain reaction (PCR) and genotyped by restriction analysis of amplimers. Copy numbers in lesions were determined using real-time PCR. Prevalence rates, copy number distributions, and association with risk factors and diseases were analysed using chi-square test, t -test, and logistic regression, respectively.
Results: We detected HPVs significantly more frequently in lesions than in controls ( P ≤ 0.001 in all comparisons). HPV prevalence increased gradually with increasing severity of lesions (32.8, 40.9, and 47.7% in OLP, OL, and OSCC, respectively). Copy number distribution patterns roughly corresponded to prevalence rates, but OLP and OL were comparable. HPV prevalence differed significantly between EA-OLP and non-EA-OLP groups (42.6 vs. 22.4%); EA-OLP group showed a prevalence similar to that found in OL.
Conclusion: HPVs may be involved in the development or progression of not only OSCC but also of potentially malignant oral lesions. 相似文献
996.
SCID鼠人宫颈癌组织模型的建立及其生物学特性初探 总被引:1,自引:0,他引:1
目的研究人原代宫颈癌组织在SCID鼠体内成瘤性及生物学特性。方法接种人宫颈癌组织于SCID鼠皮下,以建立人宫颈癌SCID鼠模型,观察荷瘤鼠成瘤、一般特性和移植瘤生长,组织学特性,检测肿瘤组织,外周血和肝、脾等脏器HPVDNA表达情况。结果成瘤率为100%,移植瘤生长以局部浸润为主,未见转移瘤。组织学检查所有移植瘤与种植前肿瘤组织病理检查一致,HPVDNA呈阳性,亚型与所种植人宫颈癌组织HPV亚型一致,而外周血与肝、脾等脏器HPVDNA呈阴性。结论初步建立SCID鼠人宫颈癌组织模型,其较好的模拟了人宫颈癌的生物学特性,为进一步探讨宫颈癌的发病机制及鉴定治疗的新方法提供了一个理想的动物模型。 相似文献
997.
目的探讨反向寡核苷酸探针杂交技术(PCR-RDB)在人乳头状瘤病毒(HPV)分型检测中的临床应用。方法采用PCR-RDB对524例HPV感染的女性生殖道标本进行HPV分型检测,分析各型的感染率以及感染病毒与年龄段关系。结果 524例HPV感染者共检出5种低危型和18种高危型,其中单一型感染者304例,占58.02%,2种混合感染79例,占15.07%,3种混合感染51例,占9.73%,4种混合感染45例,占8.59%,5种混合感染35例,占6.68%,>5种混合感染10例,占1.91%,低危型感染以HPV-6、11为主,高危型感染以HPV-16、18、58、52、33型为主,不同年龄段感染各型也存在差异,15~25岁感染者以低危感染为主,多重感染主要发生在该年龄段;46~55岁年龄段感染高危型较多,随着宫颈糜烂程度的增加多重感染数量也增加。结论 PCR-RDB法可检测HPV多种亚型,对HPV感染早期诊断及预防宫颈病变和治疗具有较好的临床应用价值。 相似文献
998.
目的探讨人乳头状瘤病毒(HPV)在不同宫颈病变中的型别分布特点。方法选取2008年11月-2010年5月,在医院妇科门诊就诊并经组织病理学证实的宫颈病变患者353例,采用HPV基因芯片检测及分型所有患者子宫颈分泌物中的HPV亚型。结果 353例宫颈病变患者中,184例HPV阳性,阳性率为52.1%,随着宫颈病变级别增高,HPV感染率逐渐上升(2χ趋势=89.18,P<0.001);353例宫颈病变中HPV亚型感染频度由高到低前5位依次为16、33、11、18、6;不同宫颈病变中HPV亚型分布虽有一定的差异,但HPV16感染率在宫颈各级病变中均具首位;随着宫颈病变级别增高,高危型HPV感染所占比例逐渐上升(χ2趋势=13.79,P<0.001);184例HPV基因分型检测阳性的宫颈病变中HPV多重感染率为37.5%,最常见类型为HPV16、18二重感染;除CINⅢ及宫颈癌组外,多重感染随宫颈病变级别增高而逐渐上升(χ2趋势=5.38,P<0.05);CINⅢ及宫颈癌组中74.1%为HPV16合并的单一或多重感染。结论不同宫颈病变感染HPV的优势亚型不同,其中HPV16亚型感染,是高危型HPV中影响宫颈病变的发生、发展的重要因素,具有最强的致癌性;多重感染与宫颈病变的进展相关。 相似文献
999.
目的了解HPV阳性患者宫颈病变情况。方法调查431例HPV阳性患者TCT和阴道镜下定点活检病理诊断结果,分析人乳头瘤病毒基因型在宫颈疾病中的分布特点。结果 431例HPV阳性标本中正常组(包括炎症组)占阳性样本率为55.9%(241/431)、湿疣组为6.7%(29/431)、ASCUS组为10.4%(45/431)、LSIL组为11.8%(51/431)、HSIL组为10.6%(43/431)、SCC组为5.2%(22/431)。各亚型在不同病变中的分布不同,HR-HPV亚型阳性率随感染级别的严重程度而比例升高,除湿疣组外,其它组与正常组HR-HPV亚型阳性率比较,差异无统计学意义(P〉0.05);湿疣组多重感染率为56.2%,其它组多重感染阳性率与正常组比较,差异无统计学意义(P〉0.05);各组除LSIL组和湿疣组外均以HPV16亚型感染率最高,病变组中HSIL组与SCC组HPV16阳性率与正常组相比较,差异有统计学意义(P〈0.05)。各病理级别年龄段感染率,主要以36~45岁年龄段感染为主。结论在宫颈病变中仍以高危亚型感染居多,多重感染可能并不增加宫颈癌的发生率。 相似文献
1000.
Loane Decrausaz Ana‐Rita Gonçalves Sonia Domingos‐Pereira Christelle Pythoud Jean‐Christophe Stehle John Schiller Patrice Jichlinski Denise Nardelli‐Haefliger 《International journal of cancer. Journal international du cancer》2011,128(9):2105-2113
Cervical cancer results from infection with high‐risk type human papillomaviruses (HPV). Therapeutic vaccines aiming at controlling existing genital HPV infections and associated lesions are usually tested in mice with HPV‐expressing tumor cells subcutaneously implanted into their flank. However, effective vaccine‐induced regression of these ectopic tumors strongly contrasts with the poor clinical results of these vaccines produced in patients with HPV‐associated genital neoplasia. To assess HPV therapeutic vaccines in a more relevant setting, we have, here, established an orthotopic mouse model where tumors in the genital mucosa (GM) develop after an intravaginal instillation of HPV16 E6/E7‐expressing tumor cells transduced with a luciferase‐encoding lentiviral vector for in vivo imaging of tumor growth. Tumor take was 80–90% after nonoxynol‐9 induced damage of the epithelium. Tumors remained localized in the genital tract, and histological analysis showed that most tumors grew within the squamous epithelium of the vaginal wall. Those tumors induced (i) E7‐specific CD8 T cells restricted to the GM and draining lymph nodes, in agreement with their mucosal location and (ii) high Foxp3+ CD4+ infiltrates, similarly to those found in natural non‐regressing HPV lesions. This novel genital HPV‐tumor model by requiring GM homing of vaccine‐induced immune responses able to overcome local immuno‐suppression may be more representative of the situation occurring in patients upon therapeutic vaccination. 相似文献