Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
1.
Virology (Auckl) ; 10: 1178122X19840371, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30983861

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection risk in the first month after transplantation is felt to be minimal; however, the epidemiology has not been specifically investigated, particularly in the modern era of potent immunosuppressive regimens and universal CMV prophylaxis. OBJECTIVE: The aim of this study was to describe the incidence of and risk factors associated with CMV occurring less than 30 days after transplant and evaluate the effect of very early CMV on outcomes. METHODS: Retrospective, single-center study of adult renal transplant (RTX) recipients between January 1, 1994 and December 31, 2014. RESULTS: A total of 5225 patients who received a renal transplant in the study time period were reviewed for the presence of CMV infection occurring less than 30 days after transplant. Of these, only 14 patients demonstrated this finding for an overall incidence of 0.27%. Half of these patients were considered to be at heightened risk due to being a recipient of a non-primary transplant or on chronic immunosuppression. This left seven patients without known risk factors for very early CMV to evaluate. In this group, time from transplant to CMV infection was 13.5 ± 7 days. The majority (57.1%, n = 4) were high-risk serostatus (CMV D+/R-) and occurred in the valganciclovir era (71.4%, n = 5). Lymphocyte-depleting induction predominated (57.1%, n = 4). Average cold ischemic time (CIT) was 19.7 ± 7.7 hours. Three patients had post-operative complications, two required exploratory-laparotomy for hemorrhage. When evaluating outcomes, 43% (n = 3) had subsequent episodes of CMV infection, 28.6% (n = 2) developed rejection, and 28.6% (n = 2) died. Outcomes between patients with CMV infection less than 30 days and those with CMV infection more than 30 days after transplant were not significantly different. CONCLUSIONS: In our review of over 5000 kidney transplants, the incidence of CMV infection in the first 30 days after renal transplant is 0.2%. Notable common patient characteristics include hemorrhage requiring re-operation and prolonged CIT. Outcomes were similar to CMV occurring more than 30 days after transplant. This study should provide the clinician with some reassurance; despite potent immunosuppressive therapy, CMV infection in the first 30 days is unlikely.

2.
Am J Transplant ; 18(8): 1977-1985, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29446225

RESUMO

We aimed to evaluate the influence of urological complications occurring within the first year after kidney transplantation on long-term patient and graft outcomes, and sought to examine the impact of the management approach of ureteral strictures on long-term graft function. We collected data on urological complications occurring within the first year posttransplant. Graft survivals, patient survival, and rejection rates were compared between recipients with and without urological complications. Male gender of the recipient, delayed graft function, and donor age were found to be significant risk factors for urological complications after kidney transplantation (P < .05). Death censored graft survival analysis showed that only ureteral strictures had a negative impact on long-term graft survival (P = .0009) compared to other complications. Death censored graft survival was significantly shorter in kidney recipients managed initially with minimally invasive approach when compared to the recipients with no stricture (P = .001). However, graft survival was not statistically different in patients managed initially with open surgery (P = .47). Ureteral strictures following kidney transplantation appear to be strongly negatively correlated with long-term graft survival. Our analysis suggests that kidney recipients with ureteral stricture should be managed initially with open surgery, with better long-term graft survival.


Assuntos
Constrição Patológica/cirurgia , Função Retardada do Enxerto/cirurgia , Rejeição de Enxerto/cirurgia , Sobrevivência de Enxerto , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Obstrução Ureteral/cirurgia , Adulto , Constrição Patológica/etiologia , Constrição Patológica/patologia , Função Retardada do Enxerto/etiologia , Função Retardada do Enxerto/patologia , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Complicações Pós-Operatórias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Obstrução Ureteral/etiologia , Obstrução Ureteral/patologia
4.
Am J Transplant ; 17(1): 191-200, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27375072

RESUMO

For donation after circulatory death (DCD), many centers allow 1 h after treatment withdrawal to donor death for kidneys. Our center has consistently allowed 2 h. We hypothesized that waiting longer would be associated with worse outcome. A single-center, retrospective analysis of DCD kidneys transplanted between 2008 and 2013 as well as a nationwide survey of organ procurement organization DCD practices were conducted. We identified 296 DCD kidneys, of which 247 (83.4%) were transplanted and 49 (16.6%) were discarded. Of the 247 recipients, 225 (group 1; 91.1%) received kidneys with a time to death (TTD) of 0-1 h; 22 (group 2; 8.9%) received grafts with a TTD of 1-2 h. Five-year patient survival was 88.8% for group 1, and 83.9% for group 2 (p = 0.667); Graft survival was also similar, with 5-year survival of 74.1% for group 1, and 83.9% for group 2 (p = 0.507). The delayed graft function rate was the same in both groups (50.2% vs. 50.0%, p = 0.984). TTD was not predictive of graft failure. Nationally, the average maximum wait-time for DCD kidneys was 77.2 min. By waiting 2 h for DCD kidneys, we performed 9.8% more transplants without worse outcomes. Nationally, this practice would allow for hundreds of additional kidney transplants, annually.


Assuntos
Morte Encefálica , Rejeição de Enxerto/prevenção & controle , Parada Cardíaca , Falência Renal Crônica/cirurgia , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/métodos , Adulto , Seleção do Doador , Feminino , Seguimentos , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Hospitais com Alto Volume de Atendimentos , Humanos , Testes de Função Renal , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Estados Unidos
5.
Curr Transplant Rep ; 2(2): 169-175, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26000231

RESUMO

Despite significant improvement in pancreas allograft survival, rejection of the pancreas remains a major clinical problem. In addition to cellular rejection of the pancreas, antibody-mediated rejection of the pancreas is now a well-described entity. The 2011 Banff update established comprehensive guidelines for the diagnosis of acute and chronic AMR. The pancreas biopsy is critical in order to accurately diagnose and treat pancreas rejection. Other modes of monitoring pancreas rejection we feel are neither sensitive nor specific enough. In this review, we examine recent advances in the diagnosis and treatment of pancreas rejection as well as describe practical diagnostic and treatment algorithms.

7.
Transpl Immunol ; 29(1-4): 11-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24103731

RESUMO

The long-lived plasma cells, which develop after alloantigen sensitization, produce donor specific alloantibodies (DSAs) that generate a positive serum cross-match and preclude transplantation. Bortezomib, a proteasome inhibitor, is being investigated in clinical desensitization protocols, however preclinical studies in a transplant model are nonexistent. We hypothesized that sustained treatment with only a proteasome inhibitor would eliminate plasma cells and reduce DSA over time. Cardiac allografts were transplanted into murine recipients. Eight weeks after allograft rejection the proteasome inhibitor, bortezomib, was injected intravenously twice weekly for 60 days. Serum alloantibody responses were assayed using flow cross-match. Total and alloreactive plasma cell numbers were enumerated using flow cytometry and ELISPOT. All recipients of cardiac allografts rejected their graft promptly within 16 days and demonstrated alloantibody by flow cross-match. DSA was sustained in the control mice while mice treated with bortezomib had sustained elimination of DSA and a marked reduction in plasma cell population. Also, bortezomib was associated with an increased level of BLyS. Within a murine model, proteasome inhibition can eliminate alloantibody secreting plasma cells, and reduce alloantibody. Cessation of bortezomib is not associated with return of DSA.


Assuntos
Antineoplásicos/farmacologia , Ácidos Borônicos/farmacologia , Transplante de Coração , Isoanticorpos/sangue , Depleção Linfocítica , Plasmócitos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Pirazinas/farmacologia , Aloenxertos , Animais , Bortezomib , Camundongos , Camundongos Endogâmicos BALB C , Plasmócitos/patologia
8.
Cytometry A ; 79(5): 368-74, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21495181

RESUMO

Improving access to CD4 testing in resource-limited settings can be achieved through both centralized and decentralized testing networks. Decentralized testing models are more suitable for countries where the HIV epidemic affects a large portion of rural populations. Timely access to accurate CD4 results is crucial at the primary level of the health system. For the past 7 years, the Institute of Human Virology of the University of Maryland School of Medicine has implemented a flexible and sustainable three-phase model: (1) site assessment and improvement, (2) appropriate technology selection with capacity building through practical training and laboratory mentoring, and (3) quality management system strengthening and monitoring, to support accessibility to reliable CD4 counting at the point of service. CD4 testing capacity was established in 122 of 229 (53%) laboratories supported in Nigeria, Uganda, Kenya, Zambia, Tanzania, and Rwanda. Among those in rural settings, 46% (69/151) had CD4 testing available at site level, with a functioning flow cytometer installed at 28% (8/29) and 50% (61/122) of level 1 and level 2 sites, respectively. To strengthen local capacity, a total of 1,152 laboratory technicians were trained through 188 training sessions provided both on-site and at central locations. The overall quality of CD4 total testing procedure was assessed at 76% (92/121) of the laboratories, with 25% (23/92), 34% (31/92), and 33% (30/92) of them reporting excellent, good, and satisfactory performance. Balancing country-specific factors with the location of the clinic, number of patients, and the expected workload, was crucial in adapting this flexible model for decentralizing CD4 testing. The close collaboration with local governments and private vendors was key to successfully expanding access to CD4 testing within the framework of HIV care and treatment programs and for the sustainability of medical laboratories in resource-limited settings.


Assuntos
Contagem de Linfócito CD4 , Infecções por HIV/diagnóstico , África , Contagem de Linfócito CD4/economia , Contagem de Linfócito CD4/instrumentação , Contagem de Linfócito CD4/métodos , Países em Desenvolvimento , HIV , Humanos
9.
Trop Med Int Health ; 15 Suppl 1: 76-81, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20586964

RESUMO

OBJECTIVES: Large-scale provision of ART in the absence of viral load monitoring, resistance testing, and limited second-line treatment options places adherence support as a vital therapeutic intervention. We aimed to compare patient loss to follow up rates with the degree of adherence support through a retrospective review of patients enrolled in the AIDSRelief program between August 2004 and June 2005. METHODS: Loss to follow up data were analysed and programs were categorised into one of four tiered levels of adherence support models: Tier I, II, III, and IV which increase from lowest to highest support. Bivariate and t-test analyses were used to test for significant differences between the models. RESULTS: 13,391 patients at 27 treatment facilities from six African and two Caribbean countries began antiretroviral therapy within the first year of the AIDSRelief program. The mean loss to follow up within the first year was 7.5%. Eight facilities were Tier I, three (Tier II), nine (Tier III), and seven (Tier IV). Facilities in Tier I had a loss to follow up rate of 14%, Tier II (10%), Tier III (5%), and Tier IV (1%). The proportion of loss to follow up for Tier I and Tier III were significantly different from each other (P < 0.02), as were Tier I and Tier IV (P < 0.006). There were differences between Tier II and Tier IV (P < 0.009) as well as Tier III and Tier IV (P < 0.017). CONCLUSION: These data strongly support the use of proactive adherence support programs, beyond routine patient counselling and defaulter tracking to support the'public health approach'to ART.


Assuntos
Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Países em Desenvolvimento , Infecções por HIV/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Modelos Organizacionais , África , Serviços de Saúde Comunitária/organização & administração , Humanos , Perda de Seguimento , Área Carente de Assistência Médica , Estudos Retrospectivos , Índias Ocidentais
10.
Proc Natl Acad Sci U S A ; 100(18): 10411-6, 2003 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-12915736

RESUMO

Propagation of R5 strains of HIV-1 on CD4 lymphocytes and macrophages requires expression of the CCR5 coreceptor on the cell surface. Individuals lacking CCR5 (CCR5 Delta 32 homozygous genotype) are phenotypically normal and resistant to infection with HIV-1. CCR5 expression on lymphocytes depends on signaling through the IL-2 receptor. By FACS analysis we demonstrate that rapamycin (RAPA), a drug that disrupts IL-2 receptor signaling, reduces CCR5 surface expression on T cells at concentrations as low as 1 nM. In addition, lower concentrations of RAPA (0.01 nM) were sufficient to reduce CCR5 surface expression on maturing monocytes. PCR analysis on peripheral blood mononuclear cells (PBMCs) showed that RAPA interfered with CCR5 expression at the transcriptional level. Reduced expression of CCR5 on PBMCs cultured in the presence of RAPA was associated with increased extracellular levels of macrophage inflammatory protein (MIP)-1 alpha and MIP-1 beta. In infectivity assays, RAPA suppressed the replication of R5 strains of HIV-1 both in PBMC and macrophage cultures. In total PBMC cultures, RAPA-mediated inhibition of CCR5-using strains of HIV-1 occurred at 0.01 nM, a concentration of drug that is approximately 103 times lower than therapeutic through levels of drug in renal transplant recipients. In addition, RAPA enhanced the antiviral activity of the CCR5 antagonist TAK-779. These results suggest that low concentrations of RAPA may have a role in both the treatment and prevention of HIV-1 infection.


Assuntos
Fármacos Anti-HIV/farmacologia , Antagonistas dos Receptores CCR5 , Quimiocinas CC/análise , HIV-1/efeitos dos fármacos , Sirolimo/farmacologia , Amidas/farmacologia , Células Cultivadas , Quimiocina CCL4 , Quimiocina CCL5/análise , Regulação para Baixo , Humanos , Proteínas Inflamatórias de Macrófagos/análise , Compostos de Amônio Quaternário/farmacologia , Receptores CCR5/análise , Linfócitos T/química , Linfócitos T/efeitos dos fármacos
11.
J Hum Virol ; 4(3): 113-22, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11572234

RESUMO

OBJECTIVES: Because recent evidence indicates that human immunodeficiency virus type 1 (HIV-1) propagates in resting T lymphocytes in vivo, we wanted to evaluate the antiviral effects exerted by currently used nucleoside (NRTI) and non-nucleoside analog reverse transcription inhibitors in resting lymphocytes, and compare those effects to the ones obtained in activated lymphocytes. METHODS: Tissue culture antiviral assays in which target cells are lymphocytes present in a resting or activated state. Virus replication was measured by a reverse transcription (RT) assay. Cell viability was evaluated using a commercial 3-(4k5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS: In vitro results obtained with concentrations of zidovudine and stavudine equivalent to drug levels found in plasma, showed more than 99% HIV-1 inhibition in activated lymphocytes but less than 50% virus inhibition in resting lymphocytes. Conversely, plasma levels of didanosine-inhibited HIV-1 by approximately 50% and 98% in activated and resting lymphocytes, respectively. Plasma level concentration of zalcitabine, lamivudine, and abacavir inhibited viral replication by more than 90% in both resting and activated cells. CONCLUSIONS: These data demonstrate that specific NRTI antiretroviral agents have different activity against HIV RT, depending on the state of cell cycle of the infected cell. We suggest that the replication of HIV-1 in resting lymphocytes should be taken into account in the design of future clinical trials, as well as treatment antiretroviral regimens. Selection of combination RTIs so that they provide antiretroviral activity in both resting and activated lymphocytes may be a way to minimize treatment failure and the emergence of drug-resistant variants.


Assuntos
Fármacos Anti-HIV/farmacologia , HIV-1 , Linfócitos/virologia , Inibidores da Transcriptase Reversa/farmacologia , Sobrevivência Celular , Resistência Microbiana a Medicamentos , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Técnicas In Vitro , Ativação Linfocitária , Linfócitos/fisiologia , Replicação Viral
12.
J Infect Dis ; 181(3): 881-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10720508

RESUMO

A phase II efficacy trial was conducted with recombinant human immunodeficiency virus (HIV) type 1 envelope glycoprotein gp160 (rgp160) in 608 HIV-infected, asymptomatic volunteers with CD4+ cell counts >400 cells/mm3. During a 5-year study, volunteers received a 6-shot primary series of immunizations with either rgp160 or placebo over 6 months, followed by booster immunizations every 2 months. Repeated vaccination with rgp160 was safe and persistently immunogenic. Adequate follow-up and acquisition of endpoints allowed for definitive interpretation of the trial results. There was no evidence that rgp160 has efficacy as a therapeutic vaccine in early-stage HIV infection, as measured at primary endpoints (50% decline in CD4+ cell count or disease progression to Walter Reed stage 4, 5, or 6) or secondary endpoints. A transient improvement was seen in the secondary CD4 endpoint for the vaccination compared with the placebo arm, but this did not translate into improved clinical outcome.


Assuntos
Vacinas contra a AIDS/uso terapêutico , Síndrome da Imunodeficiência Adquirida/terapia , HIV-1/imunologia , Vacinas Sintéticas/uso terapêutico , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/virologia , Adolescente , Adulto , Contagem de Linfócito CD4 , Método Duplo-Cego , Feminino , Proteína gp160 do Envelope de HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Proteínas Recombinantes/imunologia
13.
AIDS Res Hum Retroviruses ; 15(9): 847-54, 1999 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-10381173

RESUMO

Antibody-dependent cellular cytotoxicity (ADCC) activity was measured in 60 human immunodeficiency virus (HIV-1)-infected patients receiving a recombinant gp160 (rgp160) envelope protein of HIV-1(NL4-3) in alum and 64 receiving placebo over a 5-year study period. There was no difference in the percentage of ADCC responders when comparing rgp160-immunized patients (mean, 78.4%) with those receiving placebo alone (mean, 81.5%) at any time point examined. Patients were further divided into progression groups regardless of their vaccine status. ADCC activity was somewhat higher in rapid than in slow-progressing groups, although the number that had detectable ADCC activity was equivalent in each group. ADCC activity of sera from rapid- and slow-progressing groups against primary or laboratory isolate envelopes was similar. This study showed that transcription with rgp160 did not appear to enhance HIV-specific ADCC activity. ADCC activity did not appear to correlate with protection against AIDS in this cohort of HIV-1-infected people.


Assuntos
Vacinas contra a AIDS/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Proteína gp160 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Vacinas Sintéticas/imunologia , Estudos de Coortes , Progressão da Doença , Método Duplo-Cego , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/prevenção & controle , Humanos , Estudos Longitudinais
14.
J Infect Dis ; 179(2): 337-44, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9878016

RESUMO

This longitudinal study was designed to evaluate cellular immunity in early-stage, asymptomatic human immunodeficiency virus (HIV)-1-infected persons (CD4 cell count,>400/mm3; median, 625/mm3) who were immunized with either recombinant (r) gp160 or placebo every 2 months for 5 years. Proliferative responses were assessed against rgp160, rp24, and a panel of recall antigens and mitogens. Despite good reactivity to recall antigens, at baseline approximately 33% had proliferative responses to gp160, and approximately 42% showed p24 gag responses. There was no statistical difference between vaccine and placebo groups for antigens or mitogens. After 1 year, approximately 73% of the subjects in the vaccine arm had new or boosted responses to gp160, versus approximately 18% in the placebo arm. Statistical significance was maintained throughout the study. Recurrent vaccination with recombinant gp160 was proven to be persistently immunogenic, increasing significantly the ability of HIV-1-infected persons to mount new proliferative responses to the vaccine.


Assuntos
Vacinas contra a AIDS/imunologia , Proteína gp160 do Envelope de HIV/imunologia , Infecções por HIV/terapia , Subpopulações de Linfócitos T/imunologia , Vacinas contra a AIDS/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Criopreservação , Método Duplo-Cego , Seguimentos , Proteína gp160 do Envelope de HIV/administração & dosagem , Infecções por HIV/imunologia , Humanos , Imunização , Leucócitos Mononucleares/imunologia , Estudos Longitudinais , Ativação Linfocitária , Pessoa de Meia-Idade , Mitógenos/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
15.
J Infect Dis ; 178(5): 1306-16, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9780250

RESUMO

Human immunodeficiency virus (HIV)-1-infected rapid and slow progressors showed differential humoral responses against HIV envelope peptides and proteins early in infection. Sera from slow progressors reacted more strongly with short envelope peptides modeling gp160NL4-3, predominantly in gp41. Reactivity to six peptides (in constant regions C3, C4, and C5 of gp120 and in gp41) correlated with slower progression. In a novel association, reactivity to three peptides (in constant regions C1 and C3 and variable region V3 of gp120) correlated with faster progression. Envelope peptide reactivity correlated with subsequent course of disease progression as strongly as did reactivity to gag p24. Patients heterozygous for 32-bp deletions in the CCR5 coreceptor reacted more frequently to an epitope in gp41. Rapid progressors had greater gp120 native-to-denatured binding ratios than did slow progressors. While antibody-dependent cellular cytotoxicity against gp120 did not strongly differentiate the groups, slow progressors showed a broader neutralization pattern against 5 primary virus isolates.


Assuntos
Anticorpos Anti-HIV/biossíntese , Infecções por HIV/imunologia , HIV-1 , Técnicas Biossensoriais , Estudos de Coortes , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Proteína gp120 do Envelope de HIV/análise , Proteína gp41 do Envelope de HIV/análise , Humanos , Epitopos Imunodominantes/análise , Fragmentos de Peptídeos/análise , Mapeamento de Peptídeos , Receptores CCR5/análise
16.
J Infect Dis ; 176(4): 1085-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9333173

RESUMO

Cellular immune responses to human immunodeficiency virus type 1 (HIV-1) infection, particularly in vivo responses, have been difficult to study in large patient cohorts because of technical impediments. By use of small peptide fragments of the HIV-1 gp120 third variable loop, the CD4 T lymphocyte epitopes of 2 HIV-infected persons were mapped using a cutaneous delayed-type hypersensitivity (DTH) assay. The in vivo DTH responses correlated with epitopes previously identified in vitro using CD4 T lymphocyte lines. The ability to determine CD4 T lymphocyte epitopes in large cohorts of patients using this simple in vivo technique would provide important diagnostic and prognostic data regarding effective immunoregulation of HIV-1. This technique should have broad applicability in HIV vaccine development and in the investigation of other immune-mediated human diseases.


Assuntos
Antígenos CD4/análise , Linfócitos T CD4-Positivos/imunologia , Mapeamento de Epitopos/métodos , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1 , Sequência de Aminoácidos , Antígenos CD4/imunologia , Linfócitos T CD4-Positivos/citologia , Divisão Celular , Células Cultivadas , Feminino , Humanos , Hipersensibilidade Tardia/imunologia , Leucócitos Mononucleares/imunologia , Masculino , Dados de Sequência Molecular , Testes Cutâneos/métodos
17.
Clin Exp Immunol ; 108(2): 243-50, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9158092

RESUMO

The failure of immune effector mechanisms to control HIV-1 infection has important consequences for the human host. In a randomized cohort of HIV-infected patients, there was striking in vitro restriction of the proliferative response to HIV-1 envelope protein (Env), gp160; only 34% of patients recognized Env. Therapeutic vaccination with recombinant gp160 or gp120 (rgp160, rgp120) reversed the restriction in vitro, with Env recognition rising to 81%. Peripheral blood mononuclear cells (PBMC) from HIV-infected vaccine recipients, placebo recipients, and seronegative volunteers were cultured with exogenous IL-7 or IL-12 and either tetanus toxoid (TT) or gp160. IL-7 significantly augmented proliferative responses to TT and gp160, whereas IL-12 only affected proliferation to gp160. IL-7, but not IL-12, increased the number of HIV-infected placebo recipients who recognized rgp160. IL-12 had its greatest effect in the induction of rgp160-specific responses from seronegative individuals. The data suggest that these two cytokines have differential activity in the relief of restricted cellular immunity to Env; the predominant effect of IL-7 is in individuals who have been primed by exposure to antigen, while the effect of IL-12 is most evident in seronegative, unprimed individuals. Modification of restricted proliferative responses to Env by vaccination or cytokines in vitro suggests that strategies incorporating IL-7 or IL-12 as adjuvants may selectively boost cellular reactivity to HIV-1.


Assuntos
Vacinas contra a AIDS/imunologia , Adjuvantes Imunológicos/farmacologia , Proteína gp160 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Interleucina-12/farmacologia , Interleucina-7/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Estudos de Coortes , Feminino , Proteína do Núcleo p24 do HIV/biossíntese , Proteína do Núcleo p24 do HIV/imunologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Toxoide Tetânico/imunologia , Vacinas Sintéticas/imunologia
18.
J Infect Dis ; 175(2): 292-301, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9203649

RESUMO

Intranasal immunization of mice with human immunodeficiency virus (HIV) rgp160 complexed to proteosomes improved anti-gp160 serum IgA and IgG titers, increased the number of gp160 peptides recognized, and stimulated anti-gp160 intestinal IgA compared with immunization with uncomplexed rgp160 in saline. These enhanced responses were especially evident when either a bioadhesive nanoemulsion (emulsomes) or cholera toxin B subunit (CTB) was added to the proteosome-rgp160 vaccine. Furthermore, anti-gp160 IgG and IgA in vaginal secretions and fecal extracts were induced after intranasal immunization with proteosome-rgp160 delivered either in saline or with emulsomes. Formulation of uncomplexed rgp160 with emulsomes or CTB also enhanced serum and selected mucosal IgA responses. Induction of serum, vaginal, bronchial, intestinal, and fecal IgA and IgG by intranasal proteosome-rgp160 vaccines delivered in saline or with emulsomes or CTB is encouraging for mucosal vaccine development to help control the spread of HIV transmission and AIDS.


Assuntos
Portadores de Fármacos , Proteína gp160 do Envelope de HIV/administração & dosagem , Proteína gp160 do Envelope de HIV/imunologia , Imunização/métodos , Nariz/imunologia , Vacinas Sintéticas/imunologia , Administração Intranasal , Animais , Sangue/imunologia , Toxina da Cólera , Emulsões , Feminino , Anticorpos Anti-HIV/imunologia , Imunidade nas Mucosas , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Intestinos/imunologia , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas , Vacinas Sintéticas/administração & dosagem , Vagina/imunologia
19.
J Hum Virol ; 1(1): 30-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-10195228

RESUMO

OBJECTIVE: To determine the relation between P53 tumor suppressor RNA expression and human immunodeficiency virus (HIV) disease progression. STUDY DESIGN/METHODS: A quantitative assay of P53 RNA expression was used to analyze a cohort of HIV-negative persons. The assay was then used in longitudinal and cross-sectional studies of HIV slow and rapid progressors. RESULTS: We demonstrate first that P53 expression in peripheral blood mononuclear cells from HIV-1-seronegative persons is minimal. Longitudinal studies in a small cohort of HIV-1-infected slow and rapid progressors reveal that rapid progressors seem to have greater P53 RNA expression over time. This was validated in a cohort of 26 HIV-1-infected persons in whom the expression of P53 RNA was significantly greater in persons with rapid progression of HIV-1 disease. CONCLUSION: These data suggest that P53 RNA expression may play a role in the pathogenesis of HIV-1 disease, though the mechanism of this interaction remains unknown.


Assuntos
Genes Supressores de Tumor , Infecções por HIV/genética , Proteína Supressora de Tumor p53/genética , Animais , Contagem de Linfócito CD4 , Células CHO , Ciclo Celular , Cricetinae , Progressão da Doença , Expressão Gênica , Infecções por HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Soronegatividade para HIV , HIV-1/fisiologia , Humanos , RNA Mensageiro/análise , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/sangue , Carga Viral
20.
J Acquir Immune Defic Syndr Hum Retrovirol ; 12(4): 329-42, 1996 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8673541

RESUMO

We had previously shown that chronically infected ACH-2 cells (HIVLAI) could be superinfected with HIVRF, that the frequency of superinfection increased with time, and that the transcription of the superinfecting virus exceeded that of the host HIVLAI provirus. In contrast, ACH-2 cells superinfected with a nef-substituted neomycin-resistant (proNEO) provirus were not detectable by DNA polymerase chain reaction (PCR) until geneticin (G418) was added, suggesting that the ability to propagate progressively in culture may be HIV strain specific. Clonal populations of ACH-2 superinfected with proNEO did not demonstrate preferential transcription of the superinfecting virus. However, clones of ACH-2 superinfected with HIVRF (ACH2/RF) showed a preponderance of HIVRF transcripts similar to that seen in bulk populations. Induction of the superinfecting virus by phorbol ester (PMA) occurred more rapidly than the hose provirus and did not equalize transcriptional activity. PCR-derived long terminal repeat (LTR) fragments and Tat cDNAs from A3.01 cells acutely infected with HIVRF or from ACH-2 cells were sequenced and tested for transactivation. The HIVLAI LTR was two to three times more Tat-responsive than the HIVRF LTR. TatRF was two to three times more transcriptionally active on either LTR than TatLAI. Demethylation with 5-azacytidine did not significantly affect HIV expression from the HIVLAI host provirus of superinfected ACH2/RF cell clones. These data suggest that the mechanism of preferential transcription in HIVRF superinfected ACH2/RF may be attributed to the Tat/TAR axis and the effect of the specific locus of host proviral integration.


Assuntos
Produtos do Gene tat/genética , HIV-1/fisiologia , Linfócitos T/virologia , Transcrição Gênica , Sequência de Aminoácidos , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Sequência de Bases , Southern Blotting , Clonagem Molecular , DNA Viral/análise , DNA Viral/química , Produtos do Gene tat/química , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Provírus/efeitos dos fármacos , Provírus/genética , Provírus/fisiologia , RNA Mensageiro/análise , RNA Viral/análise , Sequências Repetitivas de Ácido Nucleico , Superinfecção/genética , Superinfecção/virologia , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima , Produtos do Gene tat do Vírus da Imunodeficiência Humana
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA