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1.
Science ; 246(4937): 1606-8, 1989 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-2556795

RESUMO

The purified human immunodeficiency virus type-l (HIV-l) Tat protein inhibited lymphocyte proliferation induced by tetanus toxoid or Candida antigens by 66 to 97% at nanomolar concentrations of Tat. In contrast, Tat did not cause a significant reduction of lymphocyte proliferation in response to mitogens such as phytohemagglutinin or pokeweed mitogen. Inhibition was blocked by oxidation of the cysteine-rich region of Tat or by incubation with an antibody to Tat before the assay. A synthetic Tat peptide (residues 1 to 58) also inhibited antigen-stimulated proliferation. Experiments with H9 and U937 cell lines showed that Tat can easily enter both lymphocytes and monocytes. The specific inhibition of antigen-induced lymphocyte proliferation by Tat mimics the effect seen with lymphocytes from HIV-infected individuals and suggests that Tat might directly contribute to the immunosuppression associated with HIV infection.


Assuntos
Produtos do Gene tat/farmacologia , HIV-1/imunologia , Ativação Linfocitária/efeitos dos fármacos , Transativadores/farmacologia , Síndrome da Imunodeficiência Adquirida/imunologia , Células Cultivadas , Concanavalina A , Replicação do DNA/efeitos dos fármacos , Produtos do Gene tat/imunologia , HIV-1/genética , Células HeLa/metabolismo , Humanos , Terapia de Imunossupressão , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Mitógenos de Phytolacca americana , Regiões Promotoras Genéticas , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Proteína Estafilocócica A , Ativação Transcricional , Produtos do Gene tat do Vírus da Imunodeficiência Humana
2.
Genetics ; 174(3): 1441-53, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16951087

RESUMO

The evolution of the human immunodeficiency virus (HIV-1) during chronic infection involves the rapid, continuous turnover of genetic diversity. However, the role of natural selection, relative to random genetic drift, in governing this process is unclear. We tested a stochastic model of genetic drift using partial envelope sequences sampled longitudinally in 28 infected children. In each case the Bayesian posterior (empirical) distribution of coalescent genealogies was estimated using Markov chain Monte Carlo methods. Posterior predictive simulation was then used to generate a null distribution of genealogies assuming neutrality, with the null and empirical distributions compared using four genealogy-based summary statistics sensitive to nonneutral evolution. Because both null and empirical distributions were generated within a coalescent framework, we were able to explicitly account for the confounding influence of demography. From the distribution of corrected P-values across patients, we conclude that empirical genealogies are more asymmetric than expected if evolution is driven by mutation and genetic drift only, with an excess of low-frequency polymorphisms in the population. This indicates that although drift may still play an important role, natural selection has a strong influence on the evolution of HIV-1 envelope. A negative relationship between effective population size and substitution rate indicates that as the efficacy of selection increases, a smaller proportion of mutations approach fixation in the population. This suggests the presence of deleterious mutations. We therefore conclude that intrahost HIV-1 evolution in envelope is dominated by purifying selection against low-frequency deleterious mutations that do not reach fixation.


Assuntos
Evolução Molecular , Produtos do Gene env/genética , Deriva Genética , HIV-1 , Seleção Genética , Sequência de Bases , Teorema de Bayes , Criança , Doença Crônica , Simulação por Computador , Genes Virais , Infecções por HIV/genética , Humanos , Dados de Sequência Molecular , Método de Monte Carlo , Mutação , Polimorfismo Genético , Processos Estocásticos
3.
J Invest Dermatol ; 104(1): 138-41, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7798632

RESUMO

In a cross-sectional study, titers of antibodies to the E4 and E7 proteins of human papillomavirus (HPV) type 16 were measured by peptide-based enzyme-linked immunosorbent assay in 1707 sera. Sera were obtained from healthy individuals (ages 1 to 95 years), from patients with HPV-associated infection (cervical intraepithelial neoplasia and cervical cancer), and from patients who were at high risk for HPV infection (attending a sexually transmitted disease clinic or referred to a colposcopist because of an abnormal Papanicolaou smear). The prevalence of anti-E7 antibodies increased with age, although the overall prevalence in the adult population was low (10.36%) compared to the frequent detection of HPV 16 DNA in the population. This suggests that only a fraction of patients infected with HPV 16 develop an anti-E7 response. The age distribution of anti-E4 antibodies showed a different pattern, i.e., the prevalence was low in the adult population (1.14%) but exceeded 20% in children and teenagers. As the specificity of the anti-E4 reaction was supported by a highly significant association with anti-E6 positivity in children's sera (p = 0.002), it was assumed that infection with HPV 16 can occur frequently early in life. As compared to healthy controls, patients at high risk for HPV infection had a significantly higher frequency (p < 0.001) of antibodies to the HPV 16 E4 protein (but not to the E6 or the E7 protein) in their sera. Therefore, we conclude that in adults E4-specific antibodies may be a marker for virus replication.


Assuntos
Proteínas E4 de Adenovirus/imunologia , Anticorpos Antivirais/sangue , Proteínas Oncogênicas Virais/imunologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/sangue , Infecções Tumorais por Vírus/sangue , Adolescente , Adulto , Sequência de Aminoácidos , Criança , Pré-Escolar , Feminino , Humanos , Dados de Sequência Molecular , Neoplasias do Colo do Útero/sangue , Displasia do Colo do Útero/sangue
4.
Artigo em Inglês | MEDLINE | ID: mdl-1941526

RESUMO

Synthetic peptides from the major envelope protein of HTLV-I (ENV-I, amino acid 177-213) and HTLV-II (ENV-II, amino acid 173-209) and a conserved region of the transmembrane protein (TM, amino acid 378-402) were used as antigens in microtiter plate enzyme immunoassays (EIA) to detect and discriminate antibodies to HTLV-I and II. The ENV-I and ENV-II peptide EIAs were able to correctly discriminate HTLV-I and II infections in 17 of 18 subjects whose infections were determined by a gene amplification method. Sera from 100 of 107 subjects with serologically confirmed infection with HTLV-I/II and 0 of 218 seronegative controls reacted with one or more of the peptides (sensitivity, 93.5%; specificity, 100%). Ninety-six of the 100 peptide positive sera reacted exclusively with either the ENV-I or the ENV-II peptide, thereby differentiating the two viral infections. The pattern of reactivity to the ENV peptides was distinct in different populations. Patients attending an Emergency Department, who had a history of drug abuse, and male inmate entering a correctional facility only had antibody reactivity to the ENV-II peptide. Subjects from Haiti and patients with HTLV-associated neurological disease only had antibody reactivity to the ENV-I peptide. Peptide-based enzyme immunoassays that distinguish antibodies to HTLV-I and HTLV-II will facilitate studies of the epidemiology of HTLV.


Assuntos
Produtos do Gene env/imunologia , Anticorpos Anti-HTLV-I/sangue , Infecções por HTLV-I/diagnóstico , Anticorpos Anti-HTLV-II/sangue , Infecções por HTLV-II/diagnóstico , Fragmentos de Peptídeos/imunologia , Sequência de Aminoácidos , Sequência de Bases , Diagnóstico Diferencial , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
5.
Cancer Epidemiol Biomarkers Prev ; 6(4): 233-7, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9107427

RESUMO

Our objective was to examine whether past infection with human papillomavirus (HPV)-16, as determined by an antibody assay, is a risk factor for subsequent cervical cancer. Incident cases of in situ or invasive cervical cancer occurring between 1975 and 1990 in a cohort of over 11,000 healthy women in Washington County, MD, were identified. The baseline sera of cases and of matched controls, collected in 1974, were examined for IgG antibodies reactive with virus-like particles of HPV-16, a cancer-associated HPV, and HPV-6, a low-risk HPV. Postdiagnosis sera of 11 cases were also assessed similarly. Fourteen cases of invasive and 28 cases of in situ cervical cancer and 83 matched controls were evaluated. The main outcome measure was the risk of cervical cancer in women who had HPV-16 or HPV-6 antibodies in prediagnostic sera. Antibodies to HPV-16 but not to HPV-6 were a marker for subsequent occurrence of cervical cancer. Case sera were reactive more often and more strongly with HPV-16 virus-like particles than were sera of matched controls. The presence of antibodies to HPV-16 was significantly associated with an increased risk of cervical cancer (odds ratio, 3.9; 95% confidence limits, 1.4, 10.7); high antibody levels to HPV-16 were associated with an even greater risk of cervical cancer (odds ratio = 7.5, 95% confidence limits 1.5, 36.3). The association with cervical cancer was strengthened after adjustment for smoking and years of education. In tests of 11 pairs of pre- and postdiagnostic sera, HPV-16 antibodies did not decline markedly over a 7-13-year time period, and seroconversion to HPV-16 appeared to have occurred in 2 cases. The serological data indicate that HPV-16 infection is associated with future risk of cervical cancer and strengthen the evidence for the etiological role of HPVs in cervical cancer.


Assuntos
Anticorpos Antivirais/sangue , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Infecções Tumorais por Vírus/imunologia , Displasia do Colo do Útero/imunologia , Neoplasias do Colo do Útero/imunologia , Adulto , Idoso , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/patologia , Colo do Útero/imunologia , Colo do Útero/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/patologia , Risco , Fumar/efeitos adversos , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/patologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia
6.
Cancer Epidemiol Biomarkers Prev ; 3(4): 341-7, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8061584

RESUMO

Masked sera from 194 cases and 217 controls participating in a case-control study of cervical cancer in Brazil were examined for antibodies to human papillomavirus (HPV) 16 E6 and E7 by radioimmunoprecipitation assay. Radiolabeled full-length E6 and E7 proteins expressed by in vitro transcription and translation in rabbit reticulocyte lysate were used as antigens. The antibody prevalences in cases and controls were: 54.1% versus 6% for E6; 30.4% versus 4.6% for E7; 63.4% versus 10.1% for either E6 or E7; and 21.1% versus 0.5% for both E6 and E7. The corresponding odds ratios were 35 ([95% confidence interval (CI)], 15-83), 10 (95% CI, 4-25), 28 (95% CI, 13-61) and 87 (95% CI, 10-736). The most marked contrast between cases and controls was observed for sera with high antibody titers (cpm > 6000) with an odds ratio of 239 (95% CI, 29-1946) for E6 or E7. Seroreactivity in cases was partially type specific; women who had HPV-16 DNA in the genital tract had higher antibody prevalence rates than those who were negative for HPV DNA. Reactivity to the E6 protein was associated with the stage of disease; the antibody prevalence was 62.7% in cases with stages II-IV and 31.0% in cases with stage I (P < 0.005). HPV-16 serology and HPV polymerase chain reaction were compared as markers for invasive cervical cancer.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anticorpos Antivirais/sangue , Carcinoma/virologia , Proteínas Oncogênicas Virais/imunologia , Papillomaviridae/imunologia , Proteínas Repressoras , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Biomarcadores , Brasil , Carcinoma/sangue , Carcinoma/patologia , Estudos de Casos e Controles , DNA Viral/análise , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Papillomaviridae/isolamento & purificação , Proteínas E7 de Papillomavirus , Prevalência , Ensaio de Radioimunoprecipitação , Fatores de Risco , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/sangue , Neoplasias do Colo do Útero/patologia
7.
Cancer Epidemiol Biomarkers Prev ; 9(7): 761-4, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10919749

RESUMO

Due to its role in the synthesis and repair of DNA, folate may protect against the development of cervical cancer. Prospective data on the possible association between folate and cervical cancer have been lacking. There is also a paucity of prospective evidence concerning the possible associations between cervical cancer and vitamin B12, which shares pathways with folate, and homocysteine, a marker of low B vitamin concentrations. A nested case-control study was conducted to prospectively evaluate the associations between cervical cancer and serum concentrations of folate, vitamin B12, and homocysteine. Among a community-based cohort of women who donated blood in 1974 for a serum bank in Washington County, Maryland, 39 cases of cervical cancer diagnosed between 1975 and mid-1990 were included in the study (13 cases of invasive cervical cancer and 26 cases of carcinoma in situ). Two controls were matched to each case by age, race, and sex. Stored serum from the cases and controls was assayed for folate, B12, and homocysteine concentrations. For folate, adjusted odds ratios were 1.0, 0.62, and 0.60 for the low to high thirds of the serum concentrations, respectively, a trend in the protective direction that was not statistically significant (P for trend = 0.42). Overall, the results for vitamin B12 tended to mimic those for folate, whereas the associations for homocysteine tended to be in the opposite direction. None of the results of this study were statistically significant, but patterns of the associations are in accord with hypothesized mechanistic pathways concerning B vitamins and cervical cancer.


Assuntos
Ácido Fólico/sangue , Homocisteína/sangue , Neoplasias do Colo do Útero/epidemiologia , Vitamina B 12/sangue , Adulto , Estudos de Casos e Controles , Reparo do DNA , Feminino , Humanos , Razão de Chances , Medição de Risco , Neoplasias do Colo do Útero/etiologia
8.
Cancer Epidemiol Biomarkers Prev ; 8(10): 935-40, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10548324

RESUMO

Serum samples from 194 cases and 217 controls participating in a case-control study of invasive cervical cancer in Brazil were examined for antibodies to human papillomavirus (HPV) 16 virus-like particles (VLPs) by ELISA. The prevalence of antibody in cases and controls was 47.4 versus 24.4% (P < 0.001). The prevalence was higher in women who had HPV-16 DNA in the genital tract (54.2%) than in those with other HPVs (36.8%) or no HPVs (44.8%), but the differences were not statistically significant. Among cases and controls, HPV-16 VLP antibodies were associated with a greater number of lifetime sexual partners (chi2 for trend, P < 0.001). Among controls, age was inversely associated with HPV-16 VLP seroreactivity (chi2 for trend, P = 0.019). The sera were previously tested for antibodies to HPV-16 E6 and E7 oncoproteins; there was no correlation between antibody titers to HPV-16 E6 or E7 and VLPs. The HPV-16 serological assays were compared as screening tests for invasive cervical cancer. The sensitivity and specificity estimates were 47.4 and 75.6% for HPV-16 VLP serology, 63.4 and 89.9% for either HPV-16 E6 or E7 serology, and 53.6 and 93.6% for high titers of either HPV-16 E6 or E7 or VLP antibodies. The utility of HPV-16 VLP ELISA as a screening test for invasive cervical cancer is limited by a high seroprevalence in women with probable prior exposure to HVP 16 but without disease.


Assuntos
Anticorpos Antivirais/sangue , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Proteínas Repressoras , Infecções Tumorais por Vírus/imunologia , Displasia do Colo do Útero/imunologia , Neoplasias do Colo do Útero/imunologia , Adulto , Idoso , Brasil , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/imunologia , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/epidemiologia , Infecções Tumorais por Vírus/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Displasia do Colo do Útero/epidemiologia
9.
J Immunol Methods ; 67(1): 129-43, 1984 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-6366064

RESUMO

Solid phase enzyme immunoassays (EIA) are widely used for the detection of infectious agents in body fluids such as stool specimens. However, we found that stool specimens contained substances which desorb from 50% to 68% of the immunoreactant from solid phase surfaces. This desorbing activity decreased the sensitivity of EIA systems for toxin A of C. difficile, rotavirus and adenovirus. The desorbing activity in stool specimens was partially heat labile at 56 degrees C for 30 min, was present in stool fractions corresponding to an estimated molecular weight of 25,000 and was shown to degrade solid phase protein. In addition, the desorbing activity was partially reversed by specific and nonspecific protease inhibitors. Thus, the desorption may reflect the enzymatic activity of stool proteases. The desorption was markedly reduced by diluting specimens in 50% fetal calf serum or an acid-protein buffer such as 0.25 M citrate buffer, pH 4.7, containing 5% bovine serum albumin. These diluents were shown to improve the recovery of toxin A of C. difficile, rotavirus and adenovirus in EIA systems for these antigens.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias , Fezes/análise , Técnicas Imunoenzimáticas , Fosfatase Alcalina , Animais , Toxinas Bacterianas/análise , Toxinas Bacterianas/imunologia , Toxinas Bacterianas/metabolismo , Sítios de Ligação de Anticorpos , Ligação Competitiva , Infecções por Clostridium/imunologia , Cricetinae , Reações Falso-Negativas , Fezes/enzimologia , Humanos , Imunoglobulina G/metabolismo , Masculino , Mesocricetus , Peptídeo Hidrolases/metabolismo
10.
Pediatrics ; 67(3): 381-6, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7243476

RESUMO

Ten cases of antibiotic-associated pseudomembranous colitis in children are reviewed. The ages ranged from 4 years to 17 years; the most frequently implicated antimicrobial agents were penicillins in six children and clindamycin in two. Stool assays showed specimens from all ten patients yielded a cytopathic toxin which was neutralized by Clostridium sordellii antitoxin with titers ranging from 1:40 to 1:40,000. Bacterial cultures of nine specimens uniformly yielded Clostridium difficile with a median concentration of 10(5.4) organisms per gram of wet weight. All nine isolates of C difficile showed a vitro production of a cytopathic toxin which was similar to or identical with that which was detected in the original stool specimen. All ten patients recovered. Six were treated with oral vancomycin and showed a good therapeutic response; one patient, however, suffered two relapses when treatment was discontinued, requiring a total of three courses of oral vancomycin. Two patients received cholestyramine and responded well. These observations provide supportive evidence that C difficile is responsible for antibiotic-associated pseudomembranous colitis in children and document efficacy of the newer therapeutic modalities in this patient population as well.


Assuntos
Antibacterianos/efeitos adversos , Enterocolite Pseudomembranosa/induzido quimicamente , Administração Oral , Adolescente , Ampicilina/efeitos adversos , Criança , Pré-Escolar , Resina de Colestiramina/uso terapêutico , Clindamicina/efeitos adversos , Clostridium/isolamento & purificação , Infecções por Clostridium/complicações , Enterocolite Pseudomembranosa/tratamento farmacológico , Enterocolite Pseudomembranosa/etiologia , Fezes/análise , Feminino , Humanos , Lactente , Masculino , Penicilina G/efeitos adversos , Vancomicina/uso terapêutico
11.
Invest Ophthalmol Vis Sci ; 34(11): 3194-8, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8407229

RESUMO

PURPOSE: The presence of nasal discharge on a child's face increases the risk of active trachoma, suggesting that Chlamydia trachomatis in nasal secretions may be a possible source of ocular reinfection. The prevalence of chlamydia in nasal secretions and the risk of reinfection after mass treatment was investigated in a hyperendemic area of Tanzania. METHODS: In one village a total of 232 children aged 1 to 7 years were followed before and after mass treatment. Clinical trachoma, and microbiologic evidence of chlamydia, were assessed at baseline, 2 and 4 weeks into mass treatment, and 4 weeks after treatment stopped. The presence of chlamydia in ocular and nasal secretions was determined by polymerase chain reaction-enzyme immunoassay techniques. RESULTS: Of the 232 children, 59% had clinical trachoma and 27% had nasal specimens positive for chlamydia. Children with positive ocular chlamydia specimens and/or clinical trachoma were significantly more likely to have positive nasal specimens. At the end of mass treatment, only 4% of children had positive ocular specimens. However, 1 month after treatment stopped, the incidence of new infection was 21%. The rate of new ocular infections in those who had negative ocular specimens after treatment was similar between those who had positive and those who had negative nasal specimens at baseline. Positive ocular specimens at baseline was not a predictor of risk of new infection after treatment (odds ratio = 1.18, 95% confidence interval = 0.58, 2.40), suggesting these new infections were not the result of latent or persistent organism. CONCLUSIONS: These data do not support a role for nasal secretions in causing reinfection after treatment. One mass topical treatment alone is unlikely to be effective in trachoma hyperendemic areas as shown by the rapid re-emergence of infection.


Assuntos
Infecções por Chlamydia/tratamento farmacológico , Tracoma/tratamento farmacológico , Sequência de Bases , Criança , Pré-Escolar , Infecções por Chlamydia/complicações , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis/isolamento & purificação , Feminino , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Mucosa Nasal/microbiologia , Prevalência , Recidiva , Fatores de Risco , Tanzânia/epidemiologia , Tetraciclina/administração & dosagem , Tetraciclina/uso terapêutico , Tracoma/epidemiologia , Tracoma/etiologia
12.
Immunol Lett ; 51(1-2): 3-6, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8811337

RESUMO

We examined the accessory genes and envelope V3 region of provirus obtained over a 5 year period from an HIV+ long-term non-progressor with very low viral load and no in vitro recoverable virus during that same time span. LTR sequences supported normal Tat-mediated promoter activity. Multiple clones of nef sequences were highly conserved with < 10% containing frame shift or stop codon mutations. Functional analysis of the predominant nef sequence indicated wild type downregulation of surface CD4 and good function in a complementation infectivity assay. By contrast, inactivating mutations were found in 64% of amplicons containing vif, vpr, vpu, tat1, and rev1, and in 41% of amplicons containing env V3. Identical inactive sequences were obtained at an interval of 2 years, suggesting persistence of quiescent defective provirus in a long-lived clonal cell population. Furthermore, genetic distance versus time analysis revealed an absence of progressive evolution or arborization of quasispecies over time. This contrasts with data generated from other asymptomatic HIV+ individuals. The non-progressive pattern of env sequence diversity and low R2 for genetic divergence over time suggests that the defective provirus circulating in the periphery of this patient represents a randomly sampled 'fossil record' of earlier replication competent HIV-1 genomes.


Assuntos
Vírus Defeituosos/genética , Infecções por HIV/genética , Infecções por HIV/patologia , Provírus/genética , Proteínas do Envelope Viral/genética , Feminino , Produtos do Gene nef/genética , Proteína gp120 do Envelope de HIV/genética , HIV-1/genética , Humanos , Mutação , Fragmentos de Peptídeos/genética , Sequências Repetitivas de Ácido Nucleico/genética , Produtos do Gene nef do Vírus da Imunodeficiência Humana
13.
AIDS Res Hum Retroviruses ; 9(7): 627-32, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8369168

RESUMO

An enzyme immunoassay (EIA) was developed to detect secretory IgA (sIgA) antibodies to HIV-1 envelope glycoprotein, using a mouse monoclonal antibody and a highly purified, baculovirus-expressed recombinant gp160 (rgp160) as antigen. Detection of sIgA was enhanced by prior immunoprecipitation of IgG. IgG and sIgA rgp160 antibodies were measured in parotid saliva and nasal wash samples of 18 HIV-1-seropositive volunteers and 14 HIV-1-seronegative adult volunteers immunized 3 times with HIV-1 IIIB rgp160 vaccine at 1 of 4 dosage levels: 40 micrograms (N = 3), 80 micrograms (N = 3), 160 micrograms (N = 4), and 640 micrograms (N = 4). We detected rgp160-specific IgG antibody in the nasal wash samples of all HIV-1-seropositive volunteers and 4/8 vaccinees (50%) immunized with the two highest doses of rgp160 vaccine. All infected volunteers tested had rgp160-specific sIgA in their nasal wash samples. None of the vaccinees and very few of infected volunteer specimens had detectable antibody in the parotid saliva samples (5/8 had IgG and 1/8 had sIgA). We also detected IgG antibody to rgp160 in the sera of all infected volunteers and 13/14 vaccinees (93%). With this EIA, sIgA antibody can be measured in mucosal secretions of recipients of appropriate candidate HIV-1 vaccines.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/análise , Infecções por HIV/imunologia , Imunoglobulina A Secretora/análise , Mucosa Nasal/metabolismo , Saliva/imunologia , Adulto , Feminino , HIV-1/imunologia , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina A/sangue , Imunoglobulina A Secretora/sangue , Imunoglobulina G/análise , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Glândula Parótida , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Vacinas Sintéticas/imunologia
14.
AIDS Res Hum Retroviruses ; 6(6): 775-84, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2194552

RESUMO

An enzyme immunoassay was developed to detect human immunodeficiency virus type 1 (HIV-1) DNA amplified by polymerase chain reaction (PCR-EIA). A set of primers (outer set) was used in PCR to amplify a segment of the HIV-1 gag gene from peripheral blood mononuclear cells. Hybrids between the amplified DNA and a RNA probe were measured in a microtiter plate immunoassay using a beta-D-galactosidase-conjugated monoclonal antibody to DNA-RNA hybrids and a fluorescent substrate. A second set of primers (nested set) located within the outer set was used in PCR with a known template to prepare the probe. One primer of the nested set included the T7 RNA polymerase promoter at its 5' end allowing transcription of a single-stranded RNA probe. Ten copies of HIV-1 DNA could be detected by PCR-EIA (42 fluorescent units with a background of 18 fluorescent units) compared with a detection limit of 1000 copies by ethidium bromide-stained agarose gel. HIV-1 DNA was detected by PCR-EIA in peripheral blood mononuclear cells from 32 of 33 seropositive patients (range 54-810 fluorescent units), and 0 of 25 seronegative patients (range 20-40 fluorescent units) (sensitivity 97%; specificity 100%). PCR-EIA offers a practical and nonisotopic method to objectively measure PCR-amplified HIV-1 DNA and has the potential for the measurement of other microbial pathogens in human body fluids.


Assuntos
DNA Viral/sangue , HIV-1/isolamento & purificação , Técnicas Imunoenzimáticas , Sequência de Bases , Infecções por HIV/sangue , Infecções por HIV/diagnóstico , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Sondas RNA
15.
AIDS Res Hum Retroviruses ; 6(11): 1251-6, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1706607

RESUMO

An enzyme immunoassay (EIA) was developed to measure serum antibody responses of healthy adult volunteers vaccinated with 40 or 80 micrograms of human immunodeficiency virus type 1 (HIV-1) recombinant gp160 (rgp160) vaccine at 0, 1, 6, and 18 months. This assay, which used purified rgp160 as antigen, was compared with the Biotech/Du Pont HIV-1 Western blot and the Abbott HIV-1 EIA. Of 33 volunteers who received three doses of rgp160 vaccine, seroresponses were detected in 91% by rgp160 EIA, 97% by Western blot, and 30% by HIV-1 EIA. The level of IgG rgp160 EIA antibody (mainly IgG1) peaked after the third immunization; 64% of 33 vaccinees still had detectable antibody by 12 months. The fourth immunization induced anamnestic IgG EIA antibody in 23 of 24 vaccinees, with titers ranging from 1:200 to 1:25,600. Neutralizing antibody was not detected in postvaccination sera by microtiter syncytium formation inhibition assay. Additional testing of sera by EIA indicated that the immune response to the vaccine was directed toward epitopes on both gp120 and gp41. Seroresponses to the immunodominant epitopes on gp41 were infrequent and none were detected to the neutralization epitope in the V3 region of gp120. This highly sensitive EIA is useful for characterizing HIV-1-specific antibody responses induced by an HIV-1 gp160 subunit vaccine.


Assuntos
Produtos do Gene env/imunologia , Anticorpos Anti-HIV/biossíntese , HIV-1/imunologia , Precursores de Proteínas/imunologia , Vacinas Virais/imunologia , Adulto , Sequência de Aminoácidos , Western Blotting , Avaliação de Medicamentos , Epitopos , Antígenos HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp160 do Envelope de HIV , Proteína gp41 do Envelope de HIV/imunologia , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G/biossíntese , Cinética , Pessoa de Meia-Idade , Dados de Sequência Molecular , Testes de Neutralização , Vacinas Sintéticas/imunologia
16.
Fertil Steril ; 74(1): 152-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10899513

RESUMO

OBJECTIVE: To identify Chlamydia trachomatis by the polymerase chain reaction (PCR) in fallopian tube tissues with chronic salpingitis. DESIGN: Retrospective case-control study. SETTING: Academic tertiary institution. PATIENT(S): Women with a pathological diagnosis of chronic salpingitis or normal fallopian tube hospitalized between September 1992 and November 1994. Initial identification of 248 specimens with final analysis of 154. INTERVENTION(S): Paraffin-embedded fallopian tube tissues were analyzed with use of PCR to detect C. trachomatis. MAIN OUTCOME MEASURE(S): Identification of C. trachomatis DNA; demographics of age, ethnicity, parity, history of sexually transmitted disease, and surgical procedure. RESULT(S): C. trachomatis DNA was detected in 9 of 77 chronic salpingitis cases. Seventy-seven controls were negative for C. trachomatis. No statistically significant difference in age or ethnicity between cases and controls was identified. Nulliparity was more frequent in cases (26 of 74) than controls (14 of 76). Sexually transmitted disease history was more prevalent in cases (24 of 74) than controls (6 of 76). Chlamydia infection was not associated with a particular surgical indication. CONCLUSION(S): Chronic salpingitis is highly associated with the presence of C. trachomatis infection as detected by PCR.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/genética , DNA Bacteriano/análise , Salpingite/microbiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Infecções por Chlamydia/complicações , Doença Crônica , Feminino , Humanos , Pessoa de Meia-Idade , Parafina , Reação em Cadeia da Polimerase/métodos , Estudos Retrospectivos , Salpingite/etiologia
17.
Eur J Cancer Prev ; 7(4): 305-13, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9806119

RESUMO

Human papillomavirus (HPV), particularly HPV 16, is linked to the development of cervical cancer. However, the role of HPV 16 in a number of extra-cervical epithelial tumours is controversial. To assess exposure to HPV 16 in patients with different cancers, we conducted a large serosurvey of 905 patients with 21 types of tumours and measured IgG to HPV 16 virus-like particles (VLPs) using a well characterized enzyme linked immunosorbent assay (ELISA). Patients with cervical cancer were considered 'positive controls', as about half were expected to be specifically HPV 16-related. A non-cancer study group consisting of 48 patients with endocrine disorders (eg diabetes) was also tested. HPV 16 antibody prevalence was highest in patients with cancers of the cervix (52% +/- 7%), vulva (27% +/- 9%), vagina (27% +/- 13%) and penis (63% +/- 16%). Seroprevalence was much lower in the non-cancer group (4% +/- 3%) and all other cancer patients: uterus (9% +/- 4%); ovary (4% +/- 3%); testis (5% +/- 4%); prostate (6% +/- 4%); squamous carcinoma (6% +/- 3%) and adenocarcinoma (4% +/- 3%) of the lung; rectum (2% +/- 2%); pancreas (8% +/- 4%); colon (2% +/- 2%); stomach (0%); oesophagus (8% +/- 4%); buccal cavity (12% +/- 5%); breast (10% +/- 4%); non-melanomatous (9% +/- 6%) and melanomatous (6% +/- 3%) skin tumours; bladder (8% +/- 4%); and kidney (2% +/- 2%). The results confirm the strong relation of HPV with several lower anogenital tract tumours, but, at least in this population, fail to identify additional epithelial tumours associated with high seroprevalence of HPV 16 VLP antibodies.


Assuntos
Anticorpos Antivirais/análise , Carcinoma/virologia , Papillomaviridae/isolamento & purificação , Adulto , Anticorpos Antivirais/imunologia , Carcinoma/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Papillomaviridae/imunologia , Estudos Soroepidemiológicos
18.
J Clin Virol ; 57(2): 147-51, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23490398

RESUMO

BACKGROUND: Information on vaccine-type HPV seroprevalence is essential for vaccine strategies; however, limited data are available on past exposure to HPV-quadrivalent vaccine types in HIV-infected woman in Brazil. OBJECTIVES: To assess the seroprevalence for HPV types 6, 11, 16 and 18 in HIV-infected and uninfected women, from Rio de Janeiro, Brazil and to investigate potential associations with age and pregnancy status. STUDY-DESIGN: 1100-sera were tested by virus-like particle (VLPs)-based ELISA for antibodies to HPV types 16, 18, 6 and 11. Statistical analysis was carried out by STATA/SE 10.1 and comparisons among HIV-infected and HIV-uninfected women were assessed by Poisson regression models with robust variance. RESULTS: HPV-6, 11, 16 and 18 seroprevalence was significantly higher among HIV-positive women (29.9%, 8.5%, 56.2% and 38.0%, respectively) compared to HIV-negative women (10.9%, 3.5%, 30.8% and 21.7%, respectively), when adjusted by age and pregnancy status. Overall, 69.4% of HIV-infected and 41.5% of HIV-uninfected women tested positive for any HPV quadrivalent vaccine type. However 4.7% and 1.1%, respectively, tested positive for all HPV vaccine type. In HIV-uninfected women who were pregnant, we found a higher HPV-11 seroprevalence (8.5% vs. 1.5%; P < 0.001) and a lower HPV 16 seroprevalence (22.6% vs. 34.2%; P = 0.010) compared to not pregnant women. HIV-uninfected women, aged 40 or more years old had a higher HPV 16 seroprevalence compared to women aged less than 40 years old. CONCLUSIONS: We did not observe a strong association between age and positive HPV antibodies nor an association between pregnancy and HPV seroprevalence. HPV seroprevalence was significantly higher among HIV-infected women compared to HIV negative women. In both populations the seroprevalence to all four HPV vaccine types was low suggesting that women may potentially benefit from the HPV vaccines.


Assuntos
Anticorpos Antivirais/sangue , Infecções por HIV/complicações , Papillomavirus Humano 11/imunologia , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Papillomavirus Humano 6/imunologia , Infecções por Papillomavirus/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Brasil/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Humanos , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , Estudos Soroepidemiológicos
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