Infection of a chimeric simian and human immunodeficiency virus with CCR5-specific HIV-1 envelope to Rhesus macaques

Human immunodeficiency virus (HIV) infects lymphocytes and macrophages via CD4 and chemokine receptors. In this study, the infectivity of a chimeric simian and human immunodeficiency virus (SHIV) having a CCR5-specific HIV-1 envelope gene was examined. A SHIV strain termed SHIV-JRFL could enter cells via CD4 with a chemokine receptor CCR5, not CXCR4, and the viral replication was suppressed by recombinant human RANTES, one of beta-chemokines. The intravenous inoculation of SHIV-JRFL into two rhesus macaques resulted in a systemic infection, though it was rather weak. During the early infection, the production of RANTES from Con A-stimulated PBMCs of the infected monkeys increased. These results suggested that beta-chemokine has the potential to limit the infectivity of an R5-type SHIV.     

上海地区猴免疫缺陷病毒和猴D型逆转录病毒感染的血清学调查

为了解上海地区实验用猴感染猴免疫缺陷病毒(SIV)和猴D型逆转录病毒(SRV)的情况,用间接ELISA方法对2012—2015年上海各实验用猴生产单位送检的475份猴血清进行了检测。结果显示SIV抗体阳性血清20份,阳性率4.21%;SRV抗体阳性血清1份,阳性率0.21%,阳性率与送检年份和无相关性。本研究为上海地区实验用猴SIV和SRV的预防提供参考依据。     

Cytomegalovirus-associated discrete gastrointestinal masses in macaques infected with the simian immunodeficiency virus

Cytomegalovirus (CMV)-associated gastrointestinal masses have been reported in human acquired immune deficiency syndrome patients. This is the first report on CMV-associated gastrointestinal masses in simian immunodeficiency virus (SIV)-infected macaques. Two SIV-infected macaques presented at necropsy with multiple nodular or umbilicated masses within the gastrointestinal tract. In one animal, the masses were located throughout the gastrointestinal tract, whereas in the other, the masses were restricted to the proximal small intestine. Grossly, the masses were indistinguishable from those caused by neoplastic conditions such as lymphoma and, histologically, were composed of hyperplastic glandular tissue, dense neutrophilic infiltrates within the lamina propria, and multifocal proprial hemorrhage. Frequent cytomegalic cells with basophilic intranuclear inclusions were found in affected regions. Immunohistochemistry for CMV demonstrated frequent immunopositive cells within affected areas. Furthermore, immunohistochemistry for the proliferation marker Ki-67 demonstrated increased proliferation in hyperplastic glands and crypts. CMV should be considered a cause of discrete mass lesions in the gastrointestinal tract of SIV-infected macaques.     

大肠杆菌vpr基因突变株的构建及其特性鉴定

将重组自杀性质粒PYYVPR转化到含全VPR基因的E.coliMC1061感受态细胞中，利用卡那霉素抗性筛选到6个菌落，经PCR和Southern blot进一步验证，得到一个可靠的vpr同源基因突变株，即MC1061△vpr。该突变株与亲本MC1061具有相似的生长特征。噬菌体裂解试验表明，突变株对VT2噬菌体C43b不敏感，而MC1061敏感，可见大量的蚀菌斑。噬菌体溶原试验表明，MC1061和突变株MC1061△vpr对噬菌体的敏感性无差别。所有这些表明,vpr基因与VT2噬菌体的裂解性有关，可能是编码VT2噬菌体受体蛋白的基因。     

猴免疫缺陷病毒p27蛋白单克隆抗体结合抗原表位的鉴定

为鉴定抗猴免疫缺陷病毒(SIV)衣壳蛋白p27单克隆抗体(MAb) p27-A5、p27-C7和p27-D2所识别的抗原表位,本研究通过间接ELISA法相加试验对这3株MAbs结合抗原表位进行初步分析,并利用部分重叠的短肽对MAbs的结合抗原表位进行鉴定.结果表明p27-C7和p27-A5的结合抗原表位位于p27蛋白的aa61～aa76(氨基酸序列为61SEGCTPYDINQMLNCV76);p27-D2的结合抗原表位则位于aa191～aa206(氨基酸序列为191EQTDAAVKNWMTQTLL206).该结果为进一步深入了解p27的抗原特性和建立该蛋白的检测方法奠定了基础.     

Trichomonad gastritis in rhesus macaques (Macaca mulatta) infected with simian immunodeficiency virus

In a retrospective study, 51 cases of gastritis (14%) were identified from among 341 necropsies performed on simian immunodeficiency virus (SIV)-infected rhesus macaques (Macaca mulatta) at the New England Primate Research Center from 1993 to 2001. Protozoa were seen in the stomach of 13 monkeys (25%) with gastritis. Two histopathologic manifestations of gastritis were observed: seven cases of lymphoplasmacytic gastritis with trichomonad trophozoites within lumens of gastric glands and four cases of necrosuppurative gastritis containing intralesional periodic acid-Schiff-positive protozoa; two cases of gastritis had morphologic features of both types of gastritis. In instances of necrosuppurative and combined lymphoplasmacytic and necrosuppurative gastritis, protozoa were 4-35 microm in diameter and round to tear-shaped. Because of the unusual morphology of the protozoa in these latter cases, transmission electron microscopy and polymerase chain reaction (PCR) were used to further identify these organisms. The protozoa were definitively identified as Tritrichomonas in all cases on the basis of ultrastructural characteristics (flagella and undulating membranes) and amplification of a 347-bp product of the 5.8S ribosomal RNA gene of Tritrichomonas foetus, Tritrichomonas suis and Tritrichomonas mobilensis by PCR using DNA extracted from stomach tissue. On the basis of these observations, we conclude that Tritrichomonas can be a significant cofactor in the development of necrosuppurative gastritis in SIV-infected rhesus macaques.     

套式PCR在检测SHIV动物模型中的应用

用嵌合体猴/人免疫缺陷病毒接种恒河猴,进行体内连续传代,从第4次传代接种嵌合体猴/人免疫缺陷病毒的2只恒河猴外周血淋巴细胞中提取猴全基因组,针对编码嵌合体猴/人免疫缺陷病毒核心蛋白的gag基因进行引物设计,采用套式PCR对提取的全基因组进行检测。套式PCR产物电泳后得到477 bp目的片段,测序结果与GenBank中的猴免疫缺陷病毒mac239的gag序列基本一致,说明嵌合体猴/人免疫缺陷病毒已整合到恒河猴基因组中。与传统病毒分离方法相比较,套式PCR检测的灵敏度明显高于病毒分离方法,尤其在感染初期和感染后期病毒处于潜伏期或病毒载量低的情况下,套式PCR方法的优越性更是传统病毒分离方法所不能替代的。     

Necropsy findings in rhesus monkeys experimentally infected with cultured simian immunodeficiency virus (SIV)/delta

Lesions induced in rhesus monkeys by different isolates of simian immunodeficiency virus (SIV)/Delta were studied at necropsy. Four groups of monkeys were inoculated with SIV/Delta isolated from other experimentally infected rhesus monkeys, while one group was inoculated with SIV/Delta from an asymptomatic mangabey monkey. Three rhesus isolates and the mangabey isolate were virulent, killing 75-100% of infected monkeys. One rhesus isolate, which had been extensively passaged in vitro, was attenuated but was restored to virulence by single animal passage. Clinically, infected monkeys had lymphadenopathy, splenomegaly, diarrhea, and a rash. Most monkeys died of enteric disease. The following lesions were seen: weight loss, thymic atrophy, lymphoid atrophy, bone marrow hyperplasia, encephalitis, colitis, amyloidosis, hepatitis, glomerulosclerosis, and the presence of syncytial cells. One Rh Epstein-Barr virus (EBV)-related lymphoma occurred. Opportunistic agents were identified: cytomegalovirus, adenovirus, Cryptosporidia, and Pneumocystis. Shigella and Campylobacter often caused colitis.     

Lentivirus-induced pulmonary lesions in rhesus monkeys (Macaca mulatta) infected with simian immunodeficiency virus.

Necropsy reports from 28 rhesus monkeys that had been experimentally infected with simian immunodeficiency virus (SIV) and that were free of cytomegalovirus were reviewed. Lung sections from 24 of these monkeys that had no etiologic agent other than SIV detected in the lung were studied in detail by histopathologic, immunohistochemical, and electron microscopic examination and by in situ hybridization. Fourteen of the monkeys were part of a serial euthanasia study, while others were euthanatized after they became moribund. The following lesions were detected: perivascular inflammation, vasculitis, interstitial pneumonia, syncytial cells, hemorrhage, fibrin exudation, and pleural fibrosis. Perivascular inflammation was the most frequent lesion and occurred as early as 2 weeks after inoculation. Severe pneumonia and numerous syncytial cells were seen only in animals euthanatized because they had become moribund. The lesions appeared to be directly due to SIV infection. SIV antigens, RNA, and virions were detected in syncytial cells and macrophages by immunohistochemical examination, in situ hybridization, and transmission electron microscopic examination, respectively. The amount of virus present was correlated with the severity of the lesions. The SIV-induced lesions were different from those of the lymphocytic interstitial pneumonia, which occurs in human immunodeficiency virus-infected children and in ovine lentivirus-infected sheep and goats.     

Functional deficiency of polymorphonuclear leukocytes in simian acquired immunodeficiency syndrome

The functional characteristics of polymorphonuclear leukocytes (PMN), considered to be the first line of host defense against infections, from rhesus macaques confirmed to have simian retrovirus (SRV)-induced simian acquired immunodeficiency syndrome (SAIDS), were evaluated. The PMN from SRV antibody-positive macaques without clinical signs were chemotactically responsive. Their phagocytic and killing capabilities were normal, and their cell membranes were highly deformable. However, PMN from SRV antibody-positive macaques and with persistent lymphadenopathy, as well as having at least 3 of the 11 common clinical signs of AIDS, were chemotactically nonresponsive. Their phagocytic and killing capabilities were compromised, and their cell membranes were rigid and nondeformable. In general, PMN from macaques with clinically confirmed SAIDS were functionally deficient. The results are similar to those obtained in other retroviral infections and can be clinically significant, because the host defense deficiency may be responsible for the recurrent and opportunistic infections in SAIDS.     

Feline leukemia virus and feline immunodeficiency virus.

Ophthalmic manifestations of FeLV or FIV infection can occur in all ocular tissues and may be manifestations of direct viral effects or secondary to viral-related malignant transformation. Additionally, the manifestations of common feline ophthalmic pathogens may be more severe and poorly responsive to therapy because of the immunosuppressive effects of FeLV or FIV infection. Prompt diagnosis of underlying viral infection in cats with ophthalmic disease is paramount for accurate diagnosis and prognosis and is required for appropriate therapeutic decision making.     

Characterization of morphologic changes and lymphocyte subset distribution in lymph nodes from cats with naturally acquired feline immunodeficiency virus infection.

Lymph nodes were collected at biopsy or necropsy from 18 cats with naturally acquired symptomatic feline immunodeficiency virus (FIV) infection and from 18 seronegative cats. Thirty-five of the cats were domestic shorthairs and one was a Persian cross. The cats ranged from 7 months to 16 years of age and were mainly obtained from California veterinary practitioners, a California cattery, and a Veterinary Teaching Hospital. Based on clinical signs present at tissue collection, ten FIV-infected cats fell into the acquired immunodeficiency syndrome (AIDS)-related complex (ARC) clinical stage and eight in the terminal (AIDS) stage of FIV disease. All cats were FeLV negative by antigen ELISA. Histologic sections of lymph nodes from each cat were examined blindly and were categorized as hyperplastic, involuting, mixed hyperplastic and involuting, depleted, or normal based upon subjective evaluation of follicles and paracortex. The relative abundance of plasma cells was evaluated in methyl green pyronin (MGP) and hematoxylin and eosin-stained sections. Similar numbers of FIV-seropositive and -seronegative cats fell into each lymph node category. The only difference evident between FIV-infected cats and control cats was in the degree of plasmacytosis present; moderate to marked plasmacytosis was present in 13/18 FIV-infected cats but in only 3/18 control cats.(ABSTRACT TRUNCATED AT 250 WORDS)     

Molecular subtyping of feline immunodeficiency virus from cats in Melbourne

OBJECTIVE: To determine the subtypes of feline immunodeficiency virus (FIV) present in the domestic cat population in Melbourne. METHODS: Blood samples were collected from 42 cats that had serum antibodies against FIV. DNA was extracted and subjected to polymerase chain reaction (PCR) to amplify variable regions of the envelope (env) and group specific antigen (gag) genes of FIV. PCR products were directly sequenced or sequenced after cloning when direct sequencing yielded ambiguous results. Phylogenetic analysis was performed and comparisons made with representative sequences of different subtypes. RESULTS: The variable region of the env gene was successfully amplified by PCR from 41 of the 42 cats. All 41 were found to cluster with subtype A env sequences. The variable region of the gag gene was successfully amplified by PCR from all 42 cats. Forty-one were found to cluster with subtype A gag genes and one was found to cluster with subtype B sequences, suggesting that it may be derived from a recombinant env A/gag B virus. CONCLUSIONS: Subtype A is the predominant FIV type in Melbourne, although a subtype A/B recombinant was identified in the population of FIV positive cats. These results of env gene analysis were similar to those in a previous Australian study, suggesting that subtype A predominates in Australia. The results of the gag gene analysis show the importance of analysing multiple areas of the FIV genome when assigning FIV subtypes. Comparison with other major urban centres may provide useful information about the phylogenic diversity of FIV in Australia.     

Diagnosis of feline leukemia virus and feline immunodeficiency virus infections

Feline leukemia virus is an oncogenic retrovirus that can result in a wide variety of neoplastic and non-neoplastic diseases, including immunosuppression. Diagnosis of FeLV infection can be achieved by several methods, including virus isolation; IFA assay of a peripheral blood smear; and detection of a viral protein (called p27) by ELISA testing of whole blood, plasma, serum, saliva, or tears. Commercially available ELISA kits have revolutionized FeLV testing and have become very popular as "in-house" procedures. This article discusses the interpretation of ELISA results and compares them with IFA assay findings. Feline immunodeficiency virus is a lentivirus that causes immunosuppression, but not neoplasia, in cats. It originally was called feline T-lymphotropic lentivirus. Differentiating FIV infection from the immunosuppressive type of FeLV infection requires virus isolation or serology. The most rapid method for diagnosis of FIV infection is ELISA testing for antiviral antibody.     

AtPCS1基因表达载体构建与转化苜蓿的研究

扩增拟南芥(Arabidopsis thaliana)螯合肤合成酶(AtPCS1)全长基因;构建AtPCS1植物表达载体pBI 121-AtPCS1,进一步转化农杆菌EHA105;利用转化的农杆菌EHA105侵染甘农一号苜蓿(Medicago satiua)叶片,经过80～100 d的筛选与培养,获得57株再生转基因植...     

Electron microscopic investigation of CD4+ lymphocyte cell line C8166 after infection with simian immunodeficiency virus (SIV)

The SIV infection of rhesus macaques (Macaca mulatta) is the most appropriate animal model in HIV research. The permanent human T-cell line C8166 is used for in vitro SIV propagation. This paper describes ultrastructural features of the cells after infection with SIVmac. The C8166 cells are ultrastructurally characterized by a heterogenous morphology which is independent of the infection. SIV induced cell syncytia are observed 18 hours after infection. Viral particles and budding occur 48 hours p.i with a peak at the day 8. Viral particles present the typical lentiviral morphology. Using the monoclonal antibody anti SIVp28 and ultra small (0.8 nm) immunogold-silver enhancement technique, we are able to demonstrate SIV antigen immunoelectron microscopically. Therefore, this ultrastructural method is suitable to detect SIV antigen in in vivo experiments with C8166 cells from day 8 p.i. serving as positive control.     

Transmission of feline immunodeficiency virus from infected queens to kittens.

This study demonstrates the transmission of feline immunodeficiency virus (FIV) from infected queens to kittens in two separate litters. Queen 1 was infected by intravenous administration of FIV at 22 days prior to parturition. Two out of three kittens from the litter were found to be viremic at 10 weeks of age as detected by culture isolation and polymerase chain reaction detection of FIV DNA in peripheral blood mononuclear leukocytes. The third kitten remained aviremic through 40 weeks of age. Queen 2 was infected by subcutaneous administration of FIV 2 days prior to parturition. This litter also had two out of three kittens infected with FIV; however, viremia was not detected in one of the kittens until 21 weeks of age. Culture isolation was found to be superior to polymerase chain reaction for the early detection of FIV, and viremia was found to precede seroconversion by up to 4 weeks. Although all infected kittens have remained healthy, depressed CD4:CD8 lymphocyte ratios suggest that clinical disease may develop. This study suggests that FIV infection in cats may be a useful model system for the study of HIV transmission from mothers to infants.