RESUMO
Many viral infections, including HIV, exhibit sex-based pathogenic differences. However, few studies have examined vaccine-related sex differences. We compared immunogenicity and protective efficacy of monomeric SIV gp120 with oligomeric SIV gp140 in a pre-clinical rhesus macaque study and explored a subsequent sex bias in vaccine outcome. Each immunization group (16 females, 8 males) was primed twice mucosally with replication-competent Ad-recombinants encoding SIVsmH4env/rev, SIV239gag and SIV239nefΔ1-13 and boosted twice intramuscularly with SIVmac239 monomeric gp120 or oligomeric gp140 in MF59 adjuvant. Controls (7 females, 5 males) received empty Ad and MF59. Up to 9 weekly intrarectal challenges with low-dose SIVmac251 were administered until macaques became infected. We assessed vaccine-induced binding, neutralizing, and non-neutralizing antibodies, Env-specific memory B cells and plasmablasts/plasma cells (PB/PC) in bone marrow and rectal tissue, mucosal Env-specific antibodies, and Env-specific T-cells. Post-challenge, only one macaque (gp140-immunized) remained uninfected. However, SIV acquisition was significantly delayed in vaccinated females but not males, correlated with Env-specific IgA in rectal secretions, rectal Env-specific memory B cells, and PC in rectal tissue. These results extend previous correlations of mucosal antibodies and memory B cells with protective efficacy. The gp140 regimen was more immunogenic, stimulating elevated gp140 and cyclic V2 binding antibodies, ADCC and ADCP activities, bone marrow Env-specific PB/PC, and rectal gp140-specific IgG. However, immunization with gp120, the form of envelope immunogen used in RV144, the only vaccine trial to show some efficacy, provided more significant acquisition delay. Further over 40 weeks of follow-up, no gp120 immunized macaques met euthanasia criteria in contrast to 7 gp140-immunized and 2 control animals. Although males had higher binding antibodies than females, ADCC and ADCP activities were similar. The complex challenge outcomes may reflect differences in IgG subtypes, Fc glycosylation, Fc-R polymorphisms, and/or the microbiome, key areas for future studies. This first demonstration of a sex-difference in SIV vaccine-induced protection emphasizes the need for sex-balancing in vaccine trials. Our results highlight the importance of mucosal immunity and memory B cells at the SIV exposure site for protection.
Assuntos
Linfócitos B/imunologia , Mucosa Intestinal/imunologia , Vacinas contra a SAIDS/imunologia , Fatores Sexuais , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Feminino , Imunidade Celular/imunologia , Imunidade nas Mucosas/imunologia , Macaca mulatta , Masculino , Reto , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologiaRESUMO
Human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection causes B-cell dysregulation and the loss of memory B cells in peripheral blood mononuclear cells (PBMC). These effects are not completely reversed by antiretroviral treatment (ART). To further elucidate B-cell changes during chronic SIV infection and treatment, we investigated memory B-cell subpopulations and plasma cells/plasmablasts (PC/PB) in blood, bone marrow, and lymph nodes of rhesus macaques during ART and upon release from ART. Macaques previously immunized with SIV recombinants and the gp120 protein were included to assess the effects of prior vaccination. ART was administered for 11 weeks, with or without gp120 boosting at week 9. Naïve and resting, activated, and tissue-like memory B cells and PC/PB were evaluated by flow cytometry. Antibody-secreting cells (ASC) and serum antibody titers were assessed. No lasting changes in B-cell memory subpopulations occurred in bone marrow and lymph nodes, but significant decreases in numbers of activated memory B cells and increases in numbers of tissue-like memory B cells persisted in PBMC. Macaque PC/PB were found to be either CD27(+) or CD27(-) and therefore were defined as CD19(+) CD38(hi) CD138(+). The numbers of these PC/PB were transiently increased in both PBMC and bone marrow following gp120 boosting of the unvaccinated and vaccinated macaque groups. Similarly, ASC numbers in PBMC and bone marrow of the two macaque groups also transiently increased following envelope boosting. Nevertheless, serum binding titers against SIVgp120 remained unchanged. Thus, even during chronic SIV infection, B cells respond to antigen, but long-term memory does not develop, perhaps due to germinal center destruction. Earlier and/or prolonged treatment to allow the generation of virus-specific long-term memory B cells should benefit ART/therapeutic vaccination regimens.
Assuntos
Antirretrovirais/uso terapêutico , Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Memória Imunológica/imunologia , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Análise de Variância , Animais , Antirretrovirais/imunologia , Linfócitos B/citologia , Linfócitos T CD4-Positivos/imunologia , Citometria de Fluxo , Modelos Lineares , Linfonodos/citologia , Linfonodos/imunologia , Masculino , Glicoproteínas de Membrana/administração & dosagem , Plasmócitos/citologia , Plasmócitos/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Proteínas do Envelope Viral/administração & dosagem , Carga ViralRESUMO
OBJECTIVE: Increased advanced glycation end-products (AGEs) and their soluble receptors (sRAGE) have been implicated in the pathogenesis of pre-eclampsia (PE). However, this association has not been elucidated in pregnancies complicated by diabetes. We aimed to investigate the serum levels of these factors in pregnant women with Type 1 diabetes mellitus (T1DM), a condition associated with a four-fold increase in PE. DESIGN: Prospective study in women with T1DM at 12.2 ± 1.9, 21.6 ± 1.5 and 31.5 ± 1.7 weeks of gestation [mean ± standard deviation (SD); no overlap] before PE onset. SETTING: Antenatal clinics. POPULATION: Pregnant women with T1DM (n = 118; 26 developed PE) and healthy nondiabetic pregnant controls (n = 21). METHODS: Maternal serum levels of sRAGE (total circulating pool), N(ε)-(carboxymethyl)lysine (CML), hydroimidazolone (methylglyoxal-modified proteins) and total AGEs were measured by immunoassays. MAIN OUTCOME MEASURES: Serum sRAGE and AGEs in pregnant women with T1DM who subsequently developed PE (DM PE+) versus those who remained normotensive (DM PE-). RESULTS: In DM PE+ versus DM PE-, sRAGE was significantly lower in the first and second trimesters, prior to the clinical manifestation of PE (P < 0.05). Further, reflecting the net sRAGE scavenger capacity, sRAGE:hydroimidazolone was significantly lower in the second trimester (P < 0.05) and sRAGE:AGE and sRAGE:CML tended to be lower in the first trimester (P < 0.1) in women with T1DM who subsequently developed PE versus those who did not. These conclusions persisted after adjusting for prandial status, glycated haemoglobin (HbA1c), duration of diabetes, parity and mean arterial pressure as covariates. CONCLUSIONS: In the early stages of pregnancy, lower circulating sRAGE levels, and the ratio of sRAGE to AGEs, may be associated with the subsequent development of PE in women with T1DM.
Assuntos
Diabetes Mellitus Tipo 1/sangue , Produtos Finais de Glicação Avançada/sangue , Pré-Eclâmpsia/sangue , Gravidez em Diabéticas/sangue , Receptores Imunológicos/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Humanos , Imidazóis/sangue , Modelos Lineares , Lisina/análogos & derivados , Lisina/sangue , Pré-Eclâmpsia/diagnóstico , Gravidez , Estudos Prospectivos , Receptor para Produtos Finais de Glicação AvançadaRESUMO
Using monoclonal antibody 12/1-2 against a 19,000-dalton human T cell leukemia virus (HTLV) protein (anti-p19), previously demonstrated to be reactive with HTLV-infected human cells, but not in numerous other uninfected cells, we found a reactive antigen to be expressed on the neuroendocrine component of human thymic epithelial cells but not on any other normal epithelial or neuroendocrine human tissues. Moreover, this reactive antigen is acquired on neuroendocrine thymic epithelium during thymic ontogeny--first appearing on fetal thymic epithelial cells between 8 and 15 wk gestation. While only a portion of thymic epithelial cells in the subcapsular cortical region of 15- and 24-wk fetal thymuses contained anti-p19+ epithelial cells, the entire subcapsular cortical region of newborn thymus epithelium was anti-p19+. By age 3 yr, normal subjects' entire subcapsular cortical and medullary thymic epithelium was anti-p19+. Using antibody against HTLV core protein, p24, and c-DNA probes for HTLV DNA, neither HTLV-specific p24 protein nor proviral DNA could be demonstrated in anti-p19+ thymic epithelial tissue. However, thymic epithelial extracts, disrupted HTLV extracts, as well as purified HTLV p19 antigen all inhibited the binding of anti-p19 antibody to thymic epithelium. Thus, anti-p19 may recognize a determinant on an HTLV-encoded 19,000-dalton structural protein that is shared by human thymic epithelium. Alternatively, anti-p19 defines a host encoded protein that is selectively expressed by normal thymic epithelium, and is induced to be expressed in HTLV-infected malignant T cells.
Assuntos
Anticorpos Monoclonais/análise , Antígenos de Neoplasias/imunologia , Glicoproteínas de Membrana , Timo/imunologia , Infecções Tumorais por Vírus/imunologia , Adolescente , Adulto , Idoso , Animais , Reações Antígeno-Anticorpo , Antígenos de Neoplasias/análise , Sítios de Ligação de Anticorpos , Membrana Celular/imunologia , Criança , Pré-Escolar , Citoplasma/imunologia , DNA de Neoplasias/análise , Epitélio/imunologia , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Gravidez , Coelhos , Retroviridae/imunologia , Timalfasina , Timopoietinas/análise , Timosina/análogos & derivados , Timosina/análise , Timo/embriologia , Infecções Tumorais por Vírus/genéticaRESUMO
Sera from patients with cutaneous T cell lymphoma and leukemia were screened for the presence of natural antibody to the human T cell lymphoma (leukemia) virus, HTLVCR, using a solid-phase radioimmunoassay. Sera from two patients, including patient CR, from whose cultured T lymphoblastic cell line (HUT102), the retrovirus HTLVCR was isolated, reacted specifically with proteins of HTLVCR. Serum from patient CR also reacted specifically with proteins of HTLVMB, an independent but highly related retroviral isolate from a patient with Sezary T cell leukemia. The specificity for HTLVCR proteins was demonstrated by solid-phase immunocompetition assays and competition radioimmunoprecipitation assays. Analysis of radioimmunoprecipitates indicated that the natural antibodies were directed against HTLVCR core proteins with molecular weights of 24,000 and 19,000 (p24 and p19). Whereas the serum reactivities for HTLVCR proteins were shown to be highly specific, additional reactivities seen against proteins of animal retroviruses including GaLV, SSV, FeLV, and BaEV were clearly shown not to be viral specific but rather were due to reactivity with cellular antigens contaminating the viral preparations or with related antigens present in fetal calf serum. These results demonstrating natural antibodies to HTLVCR provide the first evidence for a specific antibody response to a retrovirus in humans.
Assuntos
Anticorpos Antivirais/análise , Linfoma/imunologia , Retroviridae/imunologia , Neoplasias Cutâneas/imunologia , Especificidade de Anticorpos , Linhagem Celular , Humanos , Linfócitos T/imunologia , Proteínas do Core Viral , Proteínas Virais/análiseRESUMO
Sera of family members of patients from the United States, the Caribbean, and Japan, with human T cell lymphoma-leukemia virus (HTLV) associated T cell malignancies, possess HTLV-specific antibodies directed against internal structural components of HTLV, p24 and p19. The prevalence of antibodies to HTLV is greater in family members than in random healthy donors, which supports the infectious nature of HTLV and its association with particular aggressive T cell malignancies. Expression of HTLV p24 and p19 has also been observed in cultured T cells of some healthy relatives, and intact virus particles have been released from cells of one possibly pre-leukemic family member.
Assuntos
Leucemia/microbiologia , Linfoma/microbiologia , Retroviridae/análise , Anticorpos Antineoplásicos/análise , Anticorpos Antivirais/análise , Humanos , Leucemia/genética , Linhagem , Retroviridae/imunologia , Linfócitos T/microbiologiaRESUMO
Previously, combination DNA/nonreplicating adenovirus (Ad)- or poxvirus-vectored vaccines have strongly protected against SHIV(89.6P), DNAs expressing cytokines have modulated immunity elicited by DNA vaccines, and replication-competent Ad-recombinant priming and protein boosting has strongly protected against simian immunodeficiency virus (SIV) challenge. Here we evaluated a vaccine strategy composed of these promising components. Seven rhesus macaques per group were primed twice with multigenic SIV plasmid DNA with or without interleukin-12 (IL-12) DNA or IL-15 DNA. After a multigenic replicating Ad-SIV immunization, all groups received two booster immunizations with SIV gp140 and SIV Nef protein. Four control macaques received control DNA plasmids, empty Ad vector, and adjuvant. All vaccine components were immunogenic, but the cytokine DNAs had little effect. Macaques that received IL-15-DNA exhibited higher peak anti-Nef titers, a more rapid anti-Nef anamnestic response postchallenge, and expanded CD8(CM) T cells 2 weeks postchallenge compared to the DNA-only group. Other immune responses were indistinguishable between groups. Overall, no protection against intrarectal challenge with SIV(mac251) was observed, although immunized non-Mamu-A*01 macaques as a group exhibited a statistically significant 1-log decline in acute viremia compared to non-Mamu-A*01 controls. Possible factors contributing to the poor outcome include administration of cytokine DNAs to sites different from the Ad recombinants (intramuscular and intratracheal, respectively), too few DNA priming immunizations, a suboptimal DNA delivery method, failure to ensure delivery of SIV and cytokine plasmids to the same cell, and instability and short half-life of the IL-15 component. Future experiments should address these issues to determine if this combination approach is able to control a virulent SIV challenge.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Citocinas/administração & dosagem , Vacinas contra a SAIDS/administração & dosagem , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Adenoviridae/genética , Animais , Citocinas/imunologia , Imunização Secundária , Leucócitos Mononucleares/imunologia , Macaca mulatta , Plasmídeos , Vírus da Imunodeficiência Símia/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Carga Viral , Viremia/prevenção & controleRESUMO
Human T-cell leukemia virus (HTLV) is a human type-C RNA tumor virus (retrovirus) previously identified in and isolated from several patients with T-cell leukemias or lymphomas. The known virus isolates from the United States and Japan are closely related and are found in adults with an acute malignancy of mature T cells. A related retrovirus has been found in a patient (Mo) with a somewhat different disease (a T-cell variant of relatively benign hairy cell leukemia). Serum from Mo contains antibodies to the major internal core protein (p24) of HTLV. A T-cell line established from the spleen of Mo expresses HTLV antigens. However, HTLV from Mo is significantly different from all previous HTLV isolates in immunological cross-reactivity tests of p24. The usual prototype HTLV isolate is represented as HTLV-I, and the HTLV from Mo is represented as HTLV-II. Individual members of each subgroup may then be identified by subscript initials of the patient [for example, HTLV-I(CR), HTLV-I(MB), and HTLV-II(Mo)].
Assuntos
Leucemia de Células Pilosas/microbiologia , Retroviridae/isolamento & purificação , Linfócitos T/imunologia , Anticorpos Antivirais/análise , Humanos , Retroviridae/imunologia , Linfócitos T/microbiologiaRESUMO
Nine new isolates of human T-cell leukemia-lymphoma virus (HTLV) were obtained from cells of seven patients with malignancies of mature T cells and from two clinically normal relatives of a T-cell leukemia patient. These people were from the United States, Israel, the West Indies, and Japan. The virus was detected in the fresh T cells and was isolated from the established T-cell lines. Each isolate is closely related to the first HTLV isolate, and all the new HTLV isolates were transmitted into normal human T cells obtained from the umbilical cord blood of newborns.
Assuntos
Leucemia/microbiologia , Retroviridae/isolamento & purificação , Linfócitos T/microbiologia , Linhagem Celular , Células Cultivadas , Feminino , Humanos , Masculino , Retroviridae/crescimento & desenvolvimentoRESUMO
In view of the current interest in in vivo murine models for acquired immunodeficiency syndrome (AIDS), the interaction between human immunodeficiency virus type 1 (HIV-1) and endogenous murine leukemia virus (MuLV)-related retroviruses was investigated with a human leukemic T cell line (PF-382x) that acquired xenotropic MuLV (X-MuLV) after in vivo passage in immunosuppressed mice. Despite similar levels of membrane CD4 expression and HIV-1 125I-labeled gp 120 binding, a dramatic acceleration in the time course of HIV-1 infection was observed in PF-382x compared to its X-MuLV-negative counterpart (PF-382). Moreover, PF-382 cells coinfected by X-MuLV and HIV-1 generated a progeny of phenotypically mixed viral particles, enabling HIV-1 to productively infect a panel of CD4- human cells, including B lymphoid cells and purified normal peripheral blood CD4-/CD8+ T lymphocytes. Mixed viral phenotypes were also produced by human CD4+ T cells coinfected with an amphotropic MuLV-related retrovirus (A-MuLV) and HIV-1. These data show that endogenous MuLV acquired by human cells transplanted into mice can significantly interact with HIV-1, thereby inducing important alterations of HIV-1 biological properties.
Assuntos
HIV-1/genética , Retroviridae/genética , Síndrome da Imunodeficiência Adquirida/imunologia , Animais , Anticorpos Monoclonais , Antígenos CD4/análise , Linhagem Celular , Transformação Celular Viral , Modelos Animais de Doenças , HIV-1/fisiologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/microbiologia , Humanos , Camundongos , Fenótipo , Proteínas Virais/análise , Replicação ViralRESUMO
Several isolates of a human type-C retrovirus belonging to one group, known as human T-cell leukemia virus (HTLV), have previously been obtained from patients with adult T-cell leukemia or lymphoma. The T-cell tropism of HTLV and its prevalence in the Caribbean basin prompted a search for it in patients with the epidemic T-cell immune deficiency disorder known as AIDS. Peripheral blood lymphocytes from one patient in the United States and two in France were cultured with T-cell growth factor (TCGF) an shown to express HTLV antigens. Virus from the U.S. patient was isolated and characterized and shown to be related to HTLV subgroup I. The virus was also transmitted into normal human T cells from umbilical cord blood of a newborn. Whether or not HTLV-I or other retroviruses of this family with T-cell tropism cause AIDS, it is possible that patients from whom the virus can be isolated can also transmit it to others. If the target cell of AIDS is the mature T cell as suspected, the methods used in these studies may prove useful for the long-term growth of these cells and for the identification of antigens specific for the etiological agent of AIDS.
Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Retroviridae/isolamento & purificação , Infecções Tumorais por Vírus/microbiologia , Síndrome da Imunodeficiência Adquirida/etiologia , Síndrome da Imunodeficiência Adquirida/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Feminino , Humanos , Imunidade Celular , Masculino , Linfócitos T/microbiologia , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/transmissãoRESUMO
A retrovirus isolated from three patients with the acquired immunodeficiency syndrome (AIDS) in the United States was morphologically and antigenically identical to lymphadenopathy associated virus isolated in France. Two of these isolates were from a blood donor-recipient pair, each of whom developed AIDS. Lymphadenopathy associated virus was isolated from the blood donor's lymphocytes 12 months after his onset of AIDS symptoms and from the blood recipient's lymphocytes 1 month after her onset of AIDS symptoms. Two isolates from the blood donor-recipient pair and an isolate from an epidemiologically unrelated homosexual man were examined by competitive radioimmunoassay to determine their antigenic relatedness to each other and to other human retroviruses. The major core proteins (p25) of the isolates were antigenically identical and all three isolates were identical to prototype lymphadenopathy associated virus isolated in France.
Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Doadores de Sangue , Infecções por Retroviridae/imunologia , Retroviridae/imunologia , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , Anticorpos Antivirais/imunologia , Deltaretrovirus/imunologia , Feminino , Humanos , Masculino , Reação TransfusionalRESUMO
Lymphadenopathy-associated virus ( LAV ), a human T- lymphotrophic retrovirus isolated from a homosexual man with lymphadenopathy, has been causally associated with acquired immunodeficiency syndrome (AIDS). A sensitive and specific radioimmunoprecipitation test was developed for the detection of antibodies to the major core protein of LAV , p25 (molecular weight 25,000). Antibody to LAV p25 was found in the serum of 51 of 125 AIDS patients, 81 of 113 patients with lymphadenopathy syndrome, 0 of 70 workers at the Centers for Disease Control (some of whom had handled specimens from AIDS patients), and 0 of 189 random blood donors. Of a group of 100 homosexual men from San Francisco whose serum was obtained in 1978, only one had antibody to LAV p25; in contrast, of a group of 50 homosexual men in the same community whose serum was obtained in 1984, 12 had antibodies to LAV p25.
Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Anticorpos Antivirais/imunologia , Infecções por Retroviridae/imunologia , Retroviridae/imunologia , Proteínas Virais/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Doadores de Sangue , Deltaretrovirus/imunologia , Homossexualidade , Humanos , MasculinoRESUMO
An implantation study of cerium oxide nanoparticles (CeO2-NP) combined with 28-day systemic toxicity and genotoxicity studies aligned to current regulatory standards was conducted. The results suggested that local tissue reactions caused by CeO2-NP was minimal (implantation irritation index of less than 3) and was better tolerated than most other implant materials tested in our laboratory. Furthermore, CeO2-NP showed virtually no systemic toxicity or in vivo micronucleus induction in bone marrow via implantation route. Chemical analysis showed that CeO2-NP migrated from the implant sites (250 mg per site) in low levels and was deposited predominantly in liver (191.8 ± 35.1 ng g-1 of tissue; P < 0.01), lungs (263.4 ± 30.9 ng g-1 of tissue; P < 0.001), spleen (211.2 ± 6.5 ng g-1 of tissue; P < 0.001) and kidneys (272.8 ± 20.4 ng g-1 of tissue; P < 0.001). These observations provide a base line biocompatibility and toxicity data on CeO2-NP. The current findings will also be useful in defining standards for nanoparticle containing biomaterials and devices.
RESUMO
Six black patients of Caribbean origin with adult T-cell leukemia-lymphoma, 18 of their healthy family members and relatives, and 337 healthy black individuals from the Caribbean were investigated for the presence of serum antibodies against human T-cell leukemia-lymphoma virus (HTLV). Three distinct structural proteins of this virus with molecular weights of 24,000, 19,000, and 15,000 were purified, radiolabeled, and used in radioimmune precipitation assays. Five of the patients, three of the family members (two of them spouses), and 11 of the normals had specific antibodies against at least the proteins with molecular weights of 24,000 and 19,000. High antibody titers against these proteins were often associated with antibodies against the protein with a molecular weight of 15,000. In all cases, antibody titers against this protein were considerably lower than those against the proteins with molecular weights of 24,000 and 19,000. HTLV is highly associated with Caribbean adult T-cell leukemia-lymphoma and is also endemic among the normal Caribbean population. By comparison of the frequencies of anti-HTLV positives among family members of patients and the normal population, we conclude that infection by HTLV occurs in a horizontal way and at least in the West Indian black and Japanese population probably without a requirement for uncommon genetic factors.
Assuntos
Anticorpos Antivirais/análise , Antígenos Virais/imunologia , População Negra , Leucemia/microbiologia , Linfoma/microbiologia , Retroviridae/imunologia , Adulto , Complexo Antígeno-Anticorpo , Humanos , Leucemia/imunologia , Linfoma/imunologia , Valores de Referência , Linfócitos T/imunologia , Reino Unido , Estados Unidos , Proteínas Virais/análise , Índias Ocidentais/etnologiaRESUMO
Fresh human B-lymphoblasts established in culture following exposure of adult peripheral blood leukocytes to type C retroviruses of the simian sarcoma virus/simian sarcoma-associated virus-gibbon ape leukemia virus group were analyzed in detail for the presence of the infecting virus. Viral expression ranged from production of low levels of intact virus in a few cultures to the presence of viral RNA and protein in the absence of detectable of levels of complete virus in the majority of the cultures. In situ molecular hybridization assays using 3H-labeled complementary DNA and indirect immunofluorescence assays using antibody to purified viral protein indicated that the expression of viral RNA and proteins are preferentially expressed in only a fraction of the cells in some cultures. If expression of the infecting viral sequences is necessary for the sustained growth of these cells, then those cells detectably synthesizing viral RNA and proteins may be influencing the growth of the remaining virus-negative cells. The lack of virus production in cultures synthesizing viral RNA and protein indicate that these human B-lymphocytes restrict the life cycle of these viruses at some step(s) after transcription of viral RNA or translation of viral protein.
Assuntos
Linfócitos B/microbiologia , Imunofluorescência , Humanos , Ácidos Nucleicos/análise , RNA Viral/análise , Radioimunoensaio , Retroviridae/isolamento & purificação , Vírus do Sarcoma do Macaco-Barrigudo/isolamento & purificação , Proteínas Virais/análise , Proteínas Virais/imunologiaRESUMO
To determine whether the human T-cell lymphoma-leukemia virus (HTLV) is associated with particular cancers, patient sera were surveyed for HTLV-specific antibodies. An association was seen with aggressive cancers of mature T-cells, specifically Japanese adult T-cell leukemia (ATL) and T-cell lymphosarcoma cell leukemia (TLCL), a similar cancer of Caribbean blacks. Ninety to 100% of these patients possessed HTLV-specific antibody. Forty-seven and 20% of relatives of ATL and TLCL patients, respectively, and 12 and 4% of healthy donors from ATL and TLCL endemic areas were also antibody positive. Visceral organ involvement, hypercalcemia, and skin manifestation, features of ATL and TLCL, were often seen in other antibody-positive patients. Childhood cancers, most cutaneous T-cell and all non-T-cell leukemias and lymphomas, myeloid leukemias, Hodgkin's disease, and solid tumors were not associated with HTLV. Healthy United States donors and European patients with non-malignant diseases were antibody negative. HTLV is thus associated with a subtype of adult T-cell leukemia-lymphoma, clustered in viral endemic areas, with apparent racial and geographic predilection.
Assuntos
Linfoma/microbiologia , Retroviridae/análise , Linfócitos T , Adulto , Idoso , Anticorpos Antivirais/análise , Feminino , Humanos , Japão/etnologia , Leucemia/epidemiologia , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Retroviridae/imunologia , Índias Ocidentais/etnologiaRESUMO
Human T cells immortalized by human T lymphotropic virus (HTLV)-I and HTLV-II express the genes encoding both chains of platelet-derived growth factor (PDGF). These cells produce biologically active PDGF-like molecules of 31 and 32 kD, identified in the conditioned media of the virus-infected cells by direct immunoprecipitation, under non-reducing conditions, with antisera to PDGF. Upon reduction, the PDGF-like molecules are converted to mitogenically inactive single chains of 14 and 15 kD. The HTLV-transformed cells produce PDGF-like molecules regardless of their ability to produce viral particles. No PDGF-related mRNAs, PDGF-like proteins, nor PDGF-like mitogenic activity were detected in normal human T cells stimulated by phytohemagglutinin or in a T cell line which is not infected by HTLV. It is possible that one of the pathways of immortalization of T cells by HTLV-I or II might be by activation of PDGF-related genes.
Assuntos
Transformação Celular Viral , Deltaretrovirus , Fator de Crescimento Derivado de Plaquetas/biossíntese , Linfócitos T/fisiologia , DNA/biossíntese , Regulação da Expressão Gênica , Humanos , Fator de Crescimento Derivado de Plaquetas/genética , RNA Mensageiro/genética , Receptores de Superfície Celular/fisiologia , Receptores do Fator de Crescimento Derivado de PlaquetasRESUMO
The CD4 molecule plays an essential role in mediating the transduction of intracellular signals by functioning as a coreceptor for the complex T cell receptor/CD3 and also acts as the primary receptor for human immunodeficiency virus (HIV). Several authors have shown evidence that jacalin, a plant lectin, binds to CD4 and inhibits in vitro HIV infection. We analyzed jacalin-induced intracellular signaling events in CD4(+) T cells and have shown that cell activation resulted in tyrosine phosphorylation of intracellular substrates p56(lck), p59(fyn), ZAP-70, p95 (vav), phospholipase C-gamma1, and ras activation, as assessed by conversion of ras guanosine 5'-diphosphate to ras guanosine 5'-triphosphate. We further examined extracellular regulated kinase (ERK) and c-jun NH(2)-terminal kinase (JNK) phosphorylation following stimulation with jacalin. The data indicate that the kinetics of JNK phosphorylation is delayed. Optimum phosphorylation of ERK2 was observed by 10 min, and that of JNK was observed by 30 min. Pretreatment with gp120 followed by stimulation with jacalin resulted in marked inhibition of all of the aforementioned intracellular events. The data presented here provide insight into the intracellular signaling events associated with the CD4 molecule-jacalin-gp120 interactions and HIV-induced CD4(+) T cell anergy. Jacalin may be used as a possible tool for the study of CD4-mediated signal transduction and HIV-impaired CD4(+) T cell activation.
Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Proteínas de Ciclo Celular , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Lectinas de Plantas/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Adulto , Antígenos CD4/efeitos dos fármacos , Antígenos CD4/fisiologia , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/metabolismo , Anergia Clonal/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Proteína gp120 do Envelope de HIV/farmacologia , HIV-1/fisiologia , Humanos , Interleucina-2/metabolismo , Ionomicina/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Cinética , Ativação Linfocitária/efeitos dos fármacos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Fosfolipase C gama , Fosforilação/efeitos dos fármacos , Lectinas de Plantas/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-fyn , Proteínas Proto-Oncogênicas c-vav , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fosfolipases Tipo C/metabolismo , Proteína-Tirosina Quinase ZAP-70 , Proteínas ras/metabolismoRESUMO
The third component of complement (C3) plays key roles in complement activation of both the classical and alternative pathways. The liver is the major site of C3 synthesis; monocytes, B-lymphocytes and leukemic cell lines of the myeloid lineage also synthesize C3. Here we report that the C3 gene is inactive in fresh T-cells, but active in T-cells treated with the lectin phytohemagglutinin (PHA). Northern blot hybridization studies show that PHA-activated T-cells and all the T-cell lines tested express the 5.3 kb RNA transcript reported for C3 in HepG2, a hepatoma cell line, and monocytes. We used radioimmune precipitation followed by polyacrylamide gel electrophoresis to show that PHA-stimulated T-cells and T-cell lines, which are not infected with the human T-lymphotropic virus (HTLV), synthesize and release C3 proteins with molecular masses of 185, 115 and 80 kD; HTLV-infected T-cell lines release C3 proteins of 170, 115 and 70 kD. In contrast, monocytes produced C3 proteins of 115 and 70 kD similar to the serum form of this protein. The role of T-lymphocyte C3 and the implications of HTLV-infection are discussed.