RESUMO
OBJECTIVE: To determine the ability of live attenuated canarypox virus expressing HIV antigens to induce CD8+ cytotoxic T-cell responses and to prime for neutralizing antibody responses to boosting with purified recombinant gp120 subunit vaccine. DESIGN: A prospective, double-blind, randomized, immunogenicity and safety study was conducted in healthy adults at low risk for acquiring HIV infection and who were seronegative for HIV. METHODS: CD8+ cytotoxic T-cells directed against Env or Gag expressing target cells were measured after live recombinant canarypox-HIV-1 vaccine priming (vaccine given at days 0, 7, 14 and 21). Neutralizing antibodies were measured after subunit boosting (vaccine given at days 28 and 84). RESULTS: CD8+ CTL were induced in 64% of volunteers by the live recombinant canarypox-HIV-1 vaccine. All volunteers who received two doses of subunit vaccine after live recombinant canarypox priming developed neutralizing antibodies directed against laboratory strains of HIV-1 and seven out of eight volunteers tested developed neutralizing antibodies to the primary isolate, BZ167, but to none of eight other primary isolates. Unprimed controls had low or absent neutralizing antibodies after two doses of subunit vaccine. CONCLUSIONS: The live canarypox vector was safe, stimulated cytotoxic T-cells and primed for a vigorous neutralizing antibody response upon boosting with subunit gp120 vaccine. This vaccine combination should be evaluated further for inducing protection against HIV infection.
Assuntos
Vacinas contra a AIDS/imunologia , Avipoxvirus/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Vacinas contra a AIDS/efeitos adversos , Adolescente , Adulto , Linfócitos T CD8-Positivos , Método Duplo-Cego , Anticorpos Anti-HIV/sangue , Humanos , Esquemas de Imunização , Pessoa de Meia-Idade , Testes de Neutralização , Fragmentos de Peptídeos/imunologia , Estudos Prospectivos , Linfócitos T Citotóxicos/imunologia , Vacinas SintéticasRESUMO
OBJECTIVE: To review the clinical presentation and outcome of patients with an unusual primary T + B lymphocyte immunodeficiency syndrome, characterized by the presence of T lymphocytes with no detectable gross phenotypic anomaly, but which are not activated in vitro or in vivo in response to antigens, although they do respond to mitogens. METHODS: A retrospective analysis of clinical and immunological data recorded in 25 cases. Acquired immunodeficiencies and known primary T cell immunodeficiency syndromes (severe combined immunodeficiency syndrome, Di-George syndrome, Wiskott-Aldrich syndrome, cartilage hair hypoplasia, Omenn's syndrome, ataxia telangiectasia, defective expression of major histocompatibility complex class II molecules, and defective expression of the CD3/T cell receptor complex) were excluded. RESULTS: The patients had severe and particularly protracted infections, mainly of the respiratory tract and gut. Severe viral infections, generally due to herpes viruses, occurred in nearly two-thirds of the patients, with a median follow-up of 54 months. Autoimmune manifestations are frequent (60%), targetting mainly marrow-derived cells, and were characterized by a tendency to relapse and by a dependence on immunosuppressive therapy. Allergic manifestations were also frequent (48% of cases). Eight of the 19 patients who had not undergone bone marrow transplantation died. All but one of the 11 survivors had moderate to severe sequelae. Bone marrow transplantation seemed to be the treatment of choice, because four of six recipients of HLA-identical (n = 2) or nonidentical (n = 4) marrow are alive and the immune deficiency has been corrected. CONCLUSION: Early recognition of these life-threatening syndromes may improve the chances of cure. Despite common clinical manifestations and prognosis, these functional immunodeficiencies appear heterogeneous regarding inheritance pattern and at least existence of a B cell immunodeficiency.
Assuntos
Síndromes de Imunodeficiência/imunologia , Linfócitos T/fisiologia , Adolescente , Doenças Autoimunes/etiologia , Linfócitos B/fisiologia , Transplante de Medula Óssea , Criança , Pré-Escolar , Diarreia/etiologia , Feminino , Humanos , Hipersensibilidade/etiologia , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/mortalidade , Síndromes de Imunodeficiência/terapia , Lactente , Recém-Nascido , Infecções/etiologia , Masculino , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
This report describes the one-year results of a noncomparative study designed to assess the safety and tolerance of low-dose zidovudine (azidothymidine) given orally to 60 human immunodeficiency virus type 1-infected infants and children. At baseline, the mean age was 1.9 years (+/- 1.4), and all were symptomatic: 43% were P2A and 57% were P2B to F according to the Centers for Disease Control classification. All the patients received zidovudine for at least 6 months, and 52 of them (87%) completed a full year of therapy. The mean duration of follow-up was 346 days (+/- 42) (range, 183 to 366 days). The initial therapy consisted of four daily doses of 100 mg/m2 (400 mg/m2 per day, equivalent to 20 mg/kg per day). However, this treatment was modified when neutropenia or anemia was observed. Twenty-nine children (48%) remained at the initial therapy for the entire study. Zidovudine dosage was adjusted 92 times in the other 31 children (52%), mostly due to neutropenia (83%). Altogether, the time under full-dose therapy represented 81% of the total duration of the protocol for all patients. Children with mild symptoms, P2A at study entry, were more likely to remain under full-dose therapy than children with severe symptoms, P2B to F: the time under full-dose therapy represented 91% of the duration of the protocol for the former group and only 74% for the latter one (P less than .02). No clinical adverse experiences were attributed directly to zidovudine. Thirty-seven children were prescribed trimethoprim-sulfametoxazole as a prophylaxis for Pneumocystis carinii pneumonia.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Zidovudina/uso terapêutico , Pré-Escolar , Esquema de Medicação , Tolerância a Medicamentos , Feminino , Humanos , Imunização Passiva , Lactente , Cetoconazol/uso terapêutico , Masculino , Infecções Oportunistas/prevenção & controle , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Zidovudina/administração & dosagem , Zidovudina/efeitos adversosRESUMO
The gB protein (gpUL55) of human cytomegalovirus (CMV) contains C-terminal (AD-1) and N-terminal (AD-2) linear immunodominant neutralizing domains. To measure antibodies to these epitopes, a modified protein (delta-gB) lacking heavily glycosylated intervening regions, the transmembrane domain, and the cytoplasmic domain, was expressed in recombinant baculovirus-infected cells. Eighty-six percent of 600 naturally CMV-seropositive individuals and 93% of 121 gB vaccine recipients had antibodies to delta-gB as detected by enzyme-linked immunosorbent assay (ELISA). The antibody level in vaccinees (median optical density [OD] = 1.73) exceeded that in natural seropositives (median OD = 0.94; p < .0001). Eleven percent of 95 natural seropositives and 7% of 120 gB vaccinees lacked A-gB antibodies but had neutralizing activity. Among subjects with delta-gB antibody, there were weak correlations between antibody level and neutralizing titer. These data suggest that antibodies to linear neutralizing gB domains are highly prevalent in naturally-infected individuals and regularly develop in gB vaccinees. However, for some individuals, discontinuous and/or linear epitopes not represented on delta-gB may be more important in the generation of neutralizing responses.
Assuntos
Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/imunologia , Vacinas contra Citomegalovirus/imunologia , Citomegalovirus/imunologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia , Adulto , Anticorpos Antivirais/imunologia , Baculoviridae/genética , Infecções por Citomegalovirus/virologia , Ensaio de Imunoadsorção Enzimática , Humanos , Testes de Neutralização , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Vacinas de Subunidades Antigênicas/imunologia , Proteínas do Envelope Viral/genéticaRESUMO
The safety and immunogenicity of four different regimens of CHIRON cytomegalovirus (CMV) gB subunit vaccine combined with MF59 adjuvant and administered to seropositive plasma donors were evaluated to ascertain whether vaccination of seropositive subjects would significantly increase antibody titer to gB glycoprotein. This was done to select the best vaccination regimen for generating high-titered plasma for manufacture of CMV immune globulin. No serious adverse events were attributed to this vaccine, and the vaccine was well tolerated. Only the first dose of vaccine in each regimen stimulated a four-fold or greater antibody response to gB glycoprotein and each regimen induced similar antibody titers. However, initial vaccination followed by a 1 week rest from plasmapheresis and two booster vaccinations at 8 and 24 weeks, each followed with another 1 week rest from plasmapheresis, maintained the highest geometric mean gB ELISA titer of the four regimens over the 34-week post-vaccination period. CMVIG manufactured from a pool of high titered plasma units from two of four subject groups had gB ELISA and neutralizing antibody titers nine and six times higher, respectively, compared to Cytogam, indicating that vaccination of seropositive subjects with CHIRON gB vaccine combined with MF59 adjuvant prior to harvesting plasma can enhance functional antibody in a CMVIG product.
Assuntos
Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Vacinação , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos , Infecções por Citomegalovirus/virologia , Ensaio de Imunoadsorção Enzimática , Humanos , Esquemas de Imunização , Testes de Neutralização , Polissorbatos , Esqualeno , Vacinas Virais/efeitos adversosRESUMO
Several immunogens induce HIV-specific neutralization and in vitro lymphoproliferation in adults at low HIV-1 risk, but responses in persons at high HIV-1 risk are not known. We performed a multicenter, double-blinded, adjuvant-controlled trial with two gp120 vaccines in 296 HIV-1-uninfected volunteers, including 176 reporting higher HIV-1 risk activities. The immunogens were remarkably well tolerated. After three immunizations, 210 of 241 vaccinees (87%) developed neutralizing antibodies, which persisted in 59% after 2 years. The injection drug users receiving SF-2/gp120 had decreased antibody responses relative to the lower risk groups. Envelope-specific lymphoproliferation peaked after two immunizations, and 54% of vaccinees mounted a DTH reaction to gp120 after 4 years. In summary, these immunogens have low adverse reactogenicity and induce durable antibody and T cell responses to the prototype strains. Unexpected differences in antibody responses among diverse HIV-1 risk strata lend support to the conduct of expanded phase II trials in populations other than low-risk volunteers.
Assuntos
Vacinas contra a AIDS/imunologia , Vacinas contra a AIDS/farmacologia , Infecções por HIV/prevenção & controle , HIV-1 , Vacinas contra a AIDS/efeitos adversos , Adolescente , Adulto , Sequência de Aminoácidos , Método Duplo-Cego , Feminino , Anticorpos Anti-HIV/biossíntese , Antígenos HIV/genética , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/genética , HIV-1/imunologia , Humanos , Hipersensibilidade Tardia , Técnicas In Vitro , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Testes de Neutralização , Fragmentos de Peptídeos/imunologia , Assunção de Riscos , Segurança , Fatores de TempoRESUMO
This study analyzes the correlation of basic laboratory test results with clinical outcome in 94 children with perinatally acquired human immunodeficiency virus 1 infection who did not receive zidovudine during the study period of 1983 to 1988. Two life-threatening conditions highly correlated with survival, opportunistic infection and severe encephalopathy, were the end points of the study. At a median age of 25 months 30 (32%) of the 94 children had developed such conditions (Group I), and their survival at 3 years of age was 48% (95% confidence interval, 24 to 72%), contrasting with the 97% survival rate (95% confidence interval, 94 to 100%) of the remaining 64 (68%) children who had not developed such conditions by age 25 months. (Group II). Compared with children in Group II, children with life-threatening complications were more likely at the onset of symptoms to be younger and have a lower CD4 count, an impaired in vitro lymphocytic proliferation and a lack of p18 or p25 antibodies in the Western blot profile and, during the progression of the disease, a negative slope of the subsequent CD4 counts. These results highlight the need for an early diagnosis of the human immunodeficiency virus 1 infection in children and demonstrate that it is possible to determine the prognosis of their disease as early as in the first year of life.
Assuntos
Infecções por HIV/imunologia , Infecções por HIV/mortalidade , HIV-1 , Pré-Escolar , Homólogo 5 da Proteína Cromobox , Seguimentos , Proteína do Núcleo p24 do HIV , Infecções por HIV/fisiopatologia , Humanos , Lactente , Contagem de Leucócitos , Prognóstico , Modelos de Riscos ProporcionaisAssuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/prevenção & controle , Adenoviridae/genética , Animais , Ensaios Clínicos como Assunto , Citotoxicidade Imunológica , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp160 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , Humanos , Testes de Neutralização , Pan troglodytes , Vacinas Sintéticas/imunologiaRESUMO
To examine the epidemiology and natural history of mother-to-infant transmission of human immunodeficiency virus type 1 (HIV-1), especially genetic and intrapartum exposure factors, we obtained data on twins and triplets born to women infected with the virus. 40 investigators in nine countries contributed demographic, clinical, and epidemiological data on 100 sets of twins and 1 set of triplets. Among the 66 evaluable sets, HIV-1 infection was more common in first-born than in second-born twins (p = 0.004). In 22 sets, only one twin was infected (18 first-born, 4 second-born). 50% of first-born twins delivered vaginally and 38% of first-born twins delivered by caesarean were infected, compared with 19% of second-born twins delivered by either route. HIV-1 infection status tended to be concordant in more monozygotic (14 of 17 sets) than dizygotic (26 of 43) sets, but the frequency and clinical signs of HIV-1-related disease were similar in only 3 of the 10 sets with both children infected. These findings suggest that some infants may be infected in utero before labour but that a substantial proportion of HIV-1 transmission occurs as the first twin encounters the cervix and birth canal. Such measures as cleansing of the birth canal and caesarean delivery before membrane rupture might reduce the risk of transmission for infants born to HIV-1-infected women and should be the subjects of controlled clinical trials. Caesarean section should not be regarded as a wholly preventive measure, however, since substantial proportions of both first-born and second-born twins delivered in this way were infected.
Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Ordem de Nascimento , Doenças em Gêmeos/epidemiologia , HIV-1 , Complicações Infecciosas na Gravidez , Peso ao Nascer , Cesárea , Parto Obstétrico , Feminino , Saúde Global , Humanos , Lactente , Recém-Nascido , Gravidez , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Trigêmeos , Gêmeos Dizigóticos , Gêmeos MonozigóticosRESUMO
BACKGROUND: We evaluated data from prospectively identified twins to understand better the mechanisms and covariates of mother-to-infant transmission of human immunodeficiency virus (HIV). METHODS: Using data obtained from an international collaboration and multivariate quasilikelihood modeling, we assessed concordance, birth order, route of delivery, and other factors for HIV infection in 115 prospectively studied twin pairs born to HIV-infected women. Actuarial methods were used to evaluate overall survival and survival free of acquired immunodeficiency syndrome for HIV-infected twins. RESULTS: Infection with HIV occurred in 35% of vaginally delivered firstborn (A) twins, 16% of cesarean-delivered A twins, 15% of vaginally delivered second-born (B) twins, and 8% of cesarean-delivered B twins. In a multivariate model, the adjusted odds ratios for HIV infection were 11.8 (confidence interval: 3.1 to 45.3) for concordance of infection with the co-twin, 2.8 (confidence interval: 1.6 to 5.0) for A versus B twins, and 2.7 (confidence interval: 1.1 to 6.6) for vaginally delivered versus cesarean-delivered twins. Among A twins, 52% (lower confidence limit: 6%) of the transmission risk was related to vaginal delivery. Comparing vaginally delivered A twins (infants most exposed to vaginal mucus and blood) to cesarean-delivered B twins (infants least exposed), 76% (lower confidence limit: 48%) of the transmission risk was related to vaginal exposure. Infected B twins had slightly reduced Quetelet indexes and more rapid development of illnesses related to acquired immunodeficiency syndrome. CONCLUSIONS: These results indicate that HIV infection of B twins occurs predominantly in utero, whereas infection of A twins (and, by implication, singletons) occurs predominantly intrapartum. We propose that intrapartum transmission is responsible for the majority of pediatric HIV infections and that reducing exposure to HIV in the birth canal may reduce transmission of the virus from mother to infant.
Assuntos
Doenças em Gêmeos , Infecções por HIV/transmissão , HIV-1 , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , Gêmeos , Ordem de Nascimento , Parto Obstétrico , Progressão da Doença , Doenças em Gêmeos/epidemiologia , Feminino , Infecções por HIV/congênito , Infecções por HIV/mortalidade , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Gravidez , Probabilidade , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Análise de SobrevidaRESUMO
In 34 children overcoming a severe head injury (coma greater than 1 d, mean: 10 d), the follow-up (mean: 25 m) has been correlated with several data. 1) The quality of life, according to a 3 grade-score, is mostly dependent upon the degree of neuropsychological sequelae. By decreasing frequency were noted disturbances of: memory, intelligence (the most significantly correlated with the quality of life), attention, rapidity of performances, behaviour, visuoconstructive activities. Most often several disturbances were associated, but without systematization. 2) Correlations between general outcome and early findings: a coma greater than 10 d, a subdural collection on the CT scan at 2-6 weeks have a pejorative meaning. Age does not appear to be relevant. 3) In a sequential study of neuropsychological functions, an early evaluation is poorly predictive, except in case of rapid normalization. Evaluation at 6 months gives a good picture of the outcome. Sectorial improvements can occur beyond the 1st year but do not appear to modify dramatically the general outcome.
Assuntos
Traumatismos Craniocerebrais/fisiopatologia , Adolescente , Criança , Transtornos do Comportamento Infantil/etiologia , Pré-Escolar , Transtornos Cognitivos/etiologia , Traumatismos Craniocerebrais/complicações , Feminino , Seguimentos , Humanos , Masculino , PrognósticoRESUMO
A human immunodeficiency virus (HIV) vaccine that will be useful in diverse geographic regions will need to induce a broad immune response characterized by cross-clade immunity. To test whether a clade B-based HIV candidate vaccine could induce interclade humoral responses, including neutralizing activity against primary HIV-1 isolates, sera were tested from recipients of a vaccine consisting of recombinant canarypox virus vCP205 and recombinant gp120(SF2). Serum antibodies exhibited strong immunochemical cross-reactivity with V3 peptides from clades B, C, and F, with weaker activity for several V3 peptides from clades A, D, G, and H; essentially no reactivity could be demonstrated with V3 peptides from clades E and O. Extensive cross-clade reactivity was also documented by enzyme-linked immunosorbent assay with all nine recombinant HIV envelope glycoproteins tested from clades B, D, and E. In addition, vaccinees' sera displayed significant neutralizing activity against 5 of 14 primary isolates tested, including one X4 virus and two dualtropic viruses (from clade B) and two R5 viruses (from clades B and C). This is the first demonstration of the induction by a candidate HIV vaccine constructed from clade B laboratory strains of HIV of neutralizing activity against R5 and clade C primary isolates. The data suggest that, by virtue of their ability to induce cross-clade immune responses, appropriately formulated HIV vaccines based on a finite number of HIV isolates may ultimately be able to protect against the wide range of HIV isolates affecting the populations of many geographic regions.
Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Imunização Secundária , Adolescente , Adulto , Reações Cruzadas , Feminino , Produtos do Gene env/genética , Produtos do Gene env/imunologia , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes/imunologia , Vacinas Sintéticas/imunologiaRESUMO
Most candidate human immunodeficiency virus (HIV)-1 vaccines induce antibodies that neutralize T cell line-adapted HIV-1 strains. Until recently, however, no neutralizing activity against primary HIV-1 isolates had been demonstrated in sera from human vaccinees. Since most candidate HIV-1 vaccines have been constructed from T cell line-adapted syncytium-inducing (SI) strains, experiments were done to test whether sera from recipients of SI-based vaccines could preferentially neutralize SI primary HIV-1 isolates. Various neutralization assays were performed with sera from volunteers receiving ALVACgp160MN and/or rgp120SF2. Neutralizing activity was detected against 4 of 8 SI primary isolates but against none of 5 non-SI primary isolates. The data suggest that, for the induction of neutralizing antibodies to a broad array of HIV-1 primary isolates, a polyvalent vaccine will be needed containing representatives of more than a single category of viruses.
Assuntos
Vacinas contra a AIDS/imunologia , HIV-1/imunologia , Adolescente , Adulto , Variação Antigênica , Feminino , Células Gigantes/imunologia , Células Gigantes/virologia , Anticorpos Anti-HIV/biossíntese , Proteína gp160 do Envelope de HIV/imunologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
A phase I randomized, double-blind, placebo-controlled trial was done with a cytomegalovirus (CMV) vaccine based on the envelope glycoprotein, gB, combined with a novel adjuvant, MF59. Participants received CMV gB vaccine with MF59 or CMV gB with alum or placebo at 0, 1, and 6 months. A fourth vaccine was given at 12 months to a subgroup. Levels of neutralizing antibody and antibody to gB 2 weeks after the third dose of vaccine exceeded those in seropositive control subjects. the formulation with MF59 was more immunogenic than that with alum. The optimal dose of gB appeared to be between 5 and 30 microg. The fourth dose produced a prompt rise in antibody level. There were no serious adverse events associated with vaccine. Local and systemic reactions were generally mild and, except for pain at the injection site, occurred with similar frequency in recipients of placebo and CMV vaccine.
Assuntos
Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/prevenção & controle , Citomegalovirus/imunologia , Vacinas Sintéticas/efeitos adversos , Proteínas do Envelope Viral/imunologia , Vacinas Virais/efeitos adversos , Adjuvantes Imunológicos , Adolescente , Adulto , Formação de Anticorpos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Fatores de TempoRESUMO
To determine the safety and pharmacokinetics of recombinant soluble CD4 (sCD4) administered by continuous intravenous infusion to children with symptomatic human immunodeficiency virus type 1 infection, we conducted a phase I study at the National Cancer Institute. Three dose levels of sCD4 were evaluated: 100, 300, and 1000 micrograms/kg per day. After an initial 12 weeks of treatment with sCD4 alone, dideoxyinosine at a dose of 90 mg/m2 every 8 hours was added and subjects were observed for an additional 12 weeks. Combination therapy was continued in patients in whom it was well tolerated. In addition to toxicity and pharmacokinetic monitoring, surrogate markers of antiviral activity were evaluated. Eleven children were enrolled in the study. During the 12 weeks of treatment with sCD4 alone, and during subsequent sCD4 plus dideoxyinosine combination therapy, no significant toxic reaction attributable to sCD4 or dideoxyinosine was encountered. Low-level anti-CD4 antibodies developed in two patients. Steady-state sCD4 levels increased proportionately at higher doses. The CD4 cell counts and serum p24 antigen levels did not provide evidence of antiviral activity. We conclude that sCD4 was well tolerated at doses up to 1000 micrograms/kg per day when administered by continuous intravenous infusion; however, evidence of in vivo antiviral activity was not observed in this study.
Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Antígenos CD4/uso terapêutico , Didanosina/uso terapêutico , Síndrome da Imunodeficiência Adquirida/imunologia , Adolescente , Antígenos Virais/sangue , Antígenos CD4/administração & dosagem , Linfócitos T CD4-Positivos , Criança , Pré-Escolar , Didanosina/administração & dosagem , Didanosina/farmacocinética , Avaliação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Lactente , Infusões Intravenosas , Contagem de Leucócitos , Masculino , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Resultado do TratamentoRESUMO
A fundamental goal of current strategies to develop an efficacious vaccine for AIDS is the elicitation of broadly reactive cytotoxic T lymphocyte (CTL) reactivities capable of destroying virally infected targets. Recent application of recombinant canarypox ALVAC/HIV-1 vectors as vaccine immunogens in HIV-1,-noninfected volunteers has produced CTL responses in a significant number of vaccinees. Using a newly developed targeting strategy, we examined the capacity of vaccine-induced CTL to lyse autologous targets infected with a diverse group of viral isolates. CTL derived from recipients of a canarypox ALVAC/HIV-1 gp160 (MN) vaccine were found capable of lysing autologous CD4+ lymphoblasts infected with the prototypic LAI strain of HIV-1. When tested against autologous targets infected with primary HIV-1 isolates representing genetically diverse viral clades, CTL from ALVAC/gp160 recipients showed both a broad pattern of cytolysis in which viruses from all clades tested were recognized as well as a highly restricted pattern in which no primary isolates, including clade B, were lysed. Differences in the HLA haplotypes of the volunteers immunized with the envelope vector might be a major determinant of the relative breadth of their CTL response. In contrast to ALVAC/gp160 vaccinees, recipients of the ALVAC/HIV-1 immunogen containing envelope as well as gag and protease genes consistently had CTL reactivities effective against a spectrum of primary isolate-infected targets. These studies demonstrate for the first time that clade B-based canarypox vaccines can elicit broad CTL reactivities capable of recognizing viruses belonging to genetically diverse HIV-1 clades. The results also reinforce the impact of viral core elements in the vaccine as well as the pattern of major histocompatibility complex class I allelic expression by the vaccine recipient in determining the relative breadth of the cellular response.
Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD4-Positivos/virologia , Citotoxicidade Imunológica , HIV-1/imunologia , Linfócitos T Citotóxicos/imunologia , Reações Cruzadas , Proteína gp160 do Envelope de HIV/genética , Proteína gp160 do Envelope de HIV/imunologia , HIV-1/classificação , Humanos , Subpopulações de Linfócitos , Vacinas Sintéticas/imunologia , Vaccinia virus/genéticaRESUMO
To assess the safety, pharmacokinetics, and antiviral effects of intravenous recombinant CD4 immunoglobulin G (CD4-IgG), a 12-week Phase One study with an optional maintenance phase was performed. Twenty-two subjects with advanced human immunodeficiency virus (HIV) infection were enrolled; 15 subjects completed the initial 12 weeks. CD4-IgG doses were 30, 100, or 300 micrograms/kg weekly; 1,000 micrograms/kg once, twice, or three times per week; or 3,000 micrograms/kg twice weekly. Serum concentrations of CD4-IgG increased linearly with dose, with average peak serum concentrations of 22 micrograms/ml with 1,000 micrograms/kg. CD4-IgG was well tolerated; one patient had self-limited tachycardia and flushing associated with CD4-IgG therapy. No changes were seen in CD4 cell counts, hematologic or coagulation studies, serum chemistries, HIV p24 antigen titers, or plasma HIV titers. No subject developed anti-CD4 antibodies. HIV isolates from five patients had IC90 values that were higher than the peak concentrations of CD4-IgG achieved in those patients. Additional studies that achieve higher CD4-IgG concentrations are necessary to evaluate the antiviral activity of this compound.
Assuntos
Complexo Relacionado com a AIDS/terapia , Síndrome da Imunodeficiência Adquirida/terapia , Imunoadesinas CD4/uso terapêutico , HIV-1/efeitos dos fármacos , Complexo Relacionado com a AIDS/imunologia , Complexo Relacionado com a AIDS/metabolismo , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/metabolismo , Adulto , Análise Química do Sangue , Imunoadesinas CD4/administração & dosagem , Imunoadesinas CD4/efeitos adversos , Contagem de Linfócito CD4 , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Proteína do Núcleo p24 do HIV/análise , Humanos , Injeções Intravenosas , Masculino , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêuticoRESUMO
Recombinant CD4-immunoglobulin G (rCD4-IgG) is a 98-kDa human immunoglobulin-like protein that is produced by fusing the gp120 binding domain of CD4 to the Fc portion of the human IgG1 heavy chain. This hybrid molecule was given to human immunodeficiency virus (HIV)-infected pregnant women at the onset of labor by intravenous bolus at 1 mg/kg of body weight (group A; n = 3) and 1 week prior to and at the onset of labor by the same route and at the same dose (group B; n = 3). In addition to pharmacokinetic studies, safety in the mothers and infants was determined through routine chemistries, hematology, and urinalysis; immunologic and HIV infection statuses in the infants were assessed through lymphocyte cultures, p24 antigen level determination, culture of HIV from plasma, PCR, lymphocyte subset enumeration, quantitative immunoglobulin analysis, and lymphocyte proliferation. Thirty minutes after the rCD4-IgG injection, concentrations in maternal serum were 12 to 23 micrograms/ml. These concentrations declined slowly, with initial and terminal half-lives (mean +/- standard deviation) of 9.95 +/- 3.23 and 47.6 +/- 22.3 h, respectively. Infants were born 2.6 to 46.5 h after rCD4-IgG administration; concentrations of rCD4-IgG in cord blood ranged from 28 to 107 ng/ml. The half-life of rCD4-IgG in infants ranged from 5 to 29 h. These data demonstrate that the transfer of rCD4-IgG from the mother to the fetus is rapid and that newborns do not appear to have any difficulty eliminating rCD4-IgG. No safety concerns in mothers or infants were encountered. Although the study did not address the question of efficacy, none of the infants was HIV type 1 infected 36 months later. In summary, these findings document that bifunctional immune molecules can be transported across the placenta, and this general approach may be used in the future to block vertical transmission of HIV type 1.
Assuntos
Síndrome da Imunodeficiência Adquirida/metabolismo , Imunoadesinas CD4/metabolismo , Placenta/metabolismo , Complicações Infecciosas na Gravidez/metabolismo , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , Imunoadesinas CD4/toxicidade , Protocolos Clínicos , Feminino , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Injeções Intravenosas , Troca Materno-Fetal , Gravidez , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/toxicidadeRESUMO
A vaccine breakthrough occurred in a phase 1 clinical trial of a human immunodeficiency virus (HIV) type 1 candidate subunit vaccine. The vaccine antigen, gp120SF2, is a fully glycosylated protein produced in mammalian cells from the HIVSF2 isolate. After 4 immunizations, the subject developed neutralizing antibodies and lymphoproliferative responses to the gp120 protein. About 18 weeks after the last immunization, the subject became HIV infected. During the acute phase of infection, there was high virus burden, a decline in CD4+ T lymphocytes, increases in rgp120SF2-binding antibodies and HIVSF2- and HIVMN-neutralizing antibodies, and transient lymphoproliferative responses to HIV-1 envelope and core proteins. The nucleotide sequence of the V3 loop from 2 virus isolations displayed close similarity to the V3 sequence of the vaccine antigen. Thus, the immunologic responses induced by the vaccine in this subject did not protect him from HIV-1 infection.
Assuntos
Vacinas contra a AIDS/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Adulto , Sequência de Aminoácidos , Contagem de Linfócito CD4 , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , Homossexualidade Masculina , Humanos , Imunidade Ativa , Masculino , Dados de Sequência Molecular , Testes de Neutralização , Fragmentos de Peptídeos/genética , RNA Viral/sangue , RNA Viral/genética , Análise de Sequência de DNA , VacinaçãoRESUMO
Because antibodies against human cytomegalovirus (HCMV) glycoprotein B (gB) neutralize, levels of IgG, secretory IgA (sIgA), and mucosal IgA1 antibodies to HCMV were measured in saliva and nasal washes. Ten seronegative adults lacked these antibodies, but of 10 naturally seropositive adults, 10 had IgG to gB, 5 had sIgA, and 0 had mucosal IgA. Among 12 recipients of a live HCMV vaccine, 8 had IgG to gB, 4 had sIgA, and 2 had mucosal IgA in samples collected 10-20 months after immunization; of 10 recipients of a gB vaccine, 8 had IgG to gB, 7 had sIgA, and 7 had mucosal IgA in samples collected just before or 1 month after a booster. IgG to gB and neutralizing titers in serum correlated with IgG to gB in mucosal samples. IgG to gB was in the saliva of 25 of 26 subjects with serum neutralizing titers > 1:64. Serum neutralizing titers > 1:64, whether induced by vaccine or wild type virus, are associated with mucosal IgG to HCMV.