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PURPOSE: Radiotherapy plays a major role in relieving pain caused by bone metastases; paradoxically initial flare of symptom is common. Our objectives were to assess prospectively the incidence, and to identify predictor's factors of this acute complication. PATIENT AND METHODS: Forty-one patients treated with analgesic external beam radiotherapy were followed prospectively. Patients recorded pain severity and analgesic intake was documented. Pain flare was defined as an increase of two points in the intensity of pain on the numerical scale with no reduction in analgesic intake and/or 25% increase of the analgesic intake without decreasing pain intensity. RESULTS: Primary cancer was the breast, lung and prostate in 49%, 29% and 22% of patients respectively. Twelve patients (29%) had a pain flare. No factor was significantly associated with the occurrence of this complication. A favorable analgesic response was observed in 27 patients. The pain flare was not related to subsequent analgesic response. CONCLUSION: Radiotherapy is an effective treatment of pain related to bone metastasis, but with a high incidence of painful exacerbation.
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Neoplasias Óseas/radioterapia , Dolor en Cáncer/epidemiología , Hipofraccionamiento de la Dosis de Radiación , Brote de los Síntomas , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Lung cancer is the most common cancer worldwide, but epidemiologic data from developing countries are lacking. This article reports lung cancer incidence and survival in Rabat, the capital of Morocco. METHODS: All lung cancer cases diagnosed between 2005 and 2008 were analyzed using data provided by the Rabat Cancer Registry. The standardized rate was reported using age adjustment with respect to the world standard population, and the observed survival rates were calculated using the Kaplan-Meier method. RESULTS: Three hundred fifty-one cases were registered (314 males and 37 females), aged 27-90 years (median, 59 years). The most common pathological type was adenocarcinoma (40.2%) followed by squamous cell carcinoma (31.9%); the majority of cases were diagnosed at stage IV (52%). The age-standardized incidence rate was 25.1 and 2.7 per 100,000 for males and females, respectively, and the overall observed survival rates at 1 and 5 years were 31.7% and 3.4%, respectively. The clinical stage of disease was the only independent predictor of survival. CONCLUSION: The survival rate of lung cancer in Rabat is very poor. This finding explains the need for measures to reduce the prevalence of tobacco and to improve diagnostic and therapeutic facilities for lung cancer.
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Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Marruecos/epidemiología , Prevalencia , Sistema de Registros , Tasa de SupervivenciaRESUMEN
The new niobium oxychloride cluster compound, Cs2Ti4Nb6Cl18O6, was obtained by solid-state synthesis techniques in the course of our systematic investigation of metal oxychloride systems aimed at the preparation of low-dimensional cluster compounds. Cs2Ti4Nb6Cl18O6 crystallizes in the trigonal system, with unit cell parameters a= 11.1903(7), c = 15.600(2) A, space group P3bar1c, Z = 2. Its crystal structure was determined by single-crystal X-ray diffraction techniques. The full-matrix least-squares refinement against F(2) converged to R(1) = 0.048 (F(o) > 4sigma(F(o))), wR(2) = 0.069 (all data). The structure is based on an octahedral cluster unit (Nb6Cl(i)6O(i)6)Cl(a)6 in which the six edge-bridging oxide ligands are arranged in two sets of three on opposite sides of the Nb6 octahedron. Ti(3+) ions link the clusters through O(i) and Cl(a) ligands to form linear chains running along the c axis. The location of titanium ions correlates with the arrangement of oxide ligands around the Nb6 metal core. The chains interact with each other through additional Ti(3+) and Cs(+) ions. Interchain interactions are significantly weaker than intrachain interactions, resulting in a quasi-one-dimensional character of the overall structure.
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Anti-Tat vaccination experiments were carried out in mice with a view to inducing systemic in addition to mucosal immunity. For this, three types of immunizing preparations were tested, which consisted of Tat toxoid embedded in either an adjuvant oily structure (IMS), or nanoparticles of chitosan, or microparticles of polylactide-co-glycolide (PLG). Administered by either the intranasal or oral route all preparations triggered anti-Tat IgG and IgA antibodies. Sera from mice immunized with either of these preparations could also inhibit significantly the Tat transactivating activity. These results open up a new avenue to the development of an effective anti-AIDS protective vaccine.
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Síndrome de Inmunodeficiencia Adquirida/prevención & control , Productos del Gen tat/inmunología , VIH-1/inmunología , Toxoides/administración & dosificación , Toxoides/inmunología , Vacunación , Síndrome de Inmunodeficiencia Adquirida/inmunología , Administración Intranasal , Administración Oral , Animales , Ensayo de Inmunoadsorción Enzimática , Productos del Gen tat/sangre , Inmunidad Mucosa , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Ratones , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
We have investigated the possibility of altering the electronic configuration of the niobium oxochloride cluster compound Ti2Nb6Cl14O4 (I) by doping this material with monovalent cations that can fit into cavities present in its cluster framework. The doping of I with In+ and Tl+ ions resulted in the formation of MxTi2Nb6Cl14-xO4+x (M = In, x = 0.10, 0.20, 0.27; M = Tl, x = 0.10, 0.20) in which the M+ ions partially occupy these cavities. The crystal structure analysis indicated that the additional charge provided by M+ ions is compensated by substitution of chlorine by oxygen, which leads to the cluster electronic configuration being intact. Crystal data: In0.272Ti2Nb6Cl13.728O4.272, space group C2/c (No. 15), a = 12.679(2) A, b = 14.567(2) A, c = 12.632(3) A, beta = 95.26(2) degrees, Z = 4; Tl0.196Ti2Nb6Cl13.804O4.196, space group C2/c (no. 15), a = 12.732(1) A, b = 14.607(2) A, c = 12.662(2) A, beta = 95.28(1) degrees, Z = 4.
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HPV-16 E6 and E7 oncoproteins impair the cell cycle in human uterine cervix carcinoma cells (HUCC) by acting on p53 and retinoblastoma proteins, respectively. We recently reported that E7 related into the extracellular compartment by HUCC SiHa cells could inhibit immune T-cell response to recall and alloantigens by a mechanism involving an overproduction of the immunosuppressive IFN alpha by antigen presenting cells (APCs). In this study, we found that besides E7, E6 protein and the vascular endothelium growth factor (VEGF) were released into the SiHa cell supernatants, and we further showed that extracellular E7 but not E6 oncoprotein 1) inhibits the immune cell response to recall and alloantigens, and 2) enhances the release of angiogenic cytokines, including TNF alpha, IL-1 beta and IL-6 by macrophages and/or dendritic cells. VEGF unexpectedly released by cancer cells could also contribute to angiogenesis. Thus in HUCC the same E7 oncoprotein which contributes to controlling the cancer cell cycle has the means in its extracellular configuration to contribute to microenvironmental immunosuppressive and angiogenic processes. Neutralizing anti-E7 antibodies either passively administered or induced by active immunization could represent a new immunotherapeutic endeavour to combat the immunosuppression and/or neoangiogenesis effects of extracellular E7 protein.
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Tolerancia Inmunológica/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Proteínas Oncogénicas Virales/toxicidad , Papillomaviridae/patogenicidad , Proteínas Represoras , Neoplasias del Cuello Uterino/virología , Citocinas/fisiología , Factores de Crecimiento Endotelial/fisiología , Femenino , Humanos , Linfocinas/fisiología , Proteínas E7 de Papillomavirus , Linfocitos T/inmunología , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
The human papillomavirus type 16 (HPV-16) E7 oncogenic protein is found in the culture supernatant of SiHa cells, a cervical carcinoma cell line. Extracellular E7 protein, acting as a viral toxin in human immune cells, induces the overproduction of the immune suppressive IFN alpha cytokine by APCs, and inhibits the T-cell response to recall and allogenic antigens. These effects should be taken into account for the design of anti-human cervical carcinoma vaccines.
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Inmunosupresores/inmunología , Proteínas Oncogénicas Virales/farmacología , Linfocitos T/inmunología , Animales , Cromatografía de Afinidad , Citocinas/metabolismo , Células Dendríticas/inmunología , Ensayo de Inmunoadsorción Enzimática , Escherichia coli/fisiología , Femenino , Citometría de Flujo , Humanos , Interleucina-18/inmunología , Proteínas E7 de Papillomavirus , Conejos , Células Tumorales CultivadasRESUMEN
Cultured human peripheral blood monocytes (PBMC) and the cell line H9 release a lectin. This lectin is not the previously described sarcolectin, since it does not specifically recognize the sugars lactose and sialic acid. The lectinic T-cell factor reduces the release by APCs of IFN alpha--a key cytokine known to inhibit the proliferation of activated T-lymphocytes.
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Lectinas/metabolismo , Linfocitos T/metabolismo , Aglutinación , Antibióticos Antineoplásicos/farmacología , Células Presentadoras de Antígenos/metabolismo , Línea Celular , Medio de Cultivo Libre de Suero , Humanos , Interferón-alfa/antagonistas & inhibidores , Interferón-alfa/biosíntesis , Mitomicinas/farmacologíaRESUMEN
Antiviral therapy, including antiprotease treatment, suppresses viral replication, but it does not restore the HIV-1 induced immunopathogenesis which includes IFN alpha overproduction and cellular immunosuppression. To combat HIV-1 induced immunopathogenesis, anti-IFN alpha kinoid immunization in combination with tritherapy may be beneficial to HIV-1 infected immunodeficient patients.
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Síndrome de Inmunodeficiencia Adquirida/terapia , Fármacos Anti-VIH/uso terapéutico , Antivirales/inmunología , Interferón-alfa/inmunología , Vacunas/uso terapéutico , Vacunas contra el SIDA/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/patología , Autoanticuerpos/inmunología , Quimioterapia Combinada , HumanosRESUMEN
Because administration of Tat protein, the HIV-1 toxin that induces immunosuppression and apoptosis, may be deleterious to the host immune system, a chemically inactivated but nonetheless immunogenic Tat preparation, Tat toxoid, was used to immunize seronegative individuals against Tat. In an open, controlled, phase I clinical trial, Tat toxoid turned out to be safe, well tolerated, and able to trigger a specific immune reaction. In particular, a threefold to more than 10-fold increase of circulating antibodies directed against the native Tat was observed after immunization in all of 5 immunized study subjects, together with a positive reaction to delayed-type hypersensitivity (DTH) skin test with Tat toxoid in vivo and increased lymphoproliferative response to native Tat in vitro. Persistent (> or =1 year) high levels of circulating anti-Tat antibodies could prevent the Tat-induced immune suppression and, following HIV-1 exposure, allow the anti-HIV-1 cellular immune response, with its early release of protective beta-chemokines, to occur leading to an increase of host resistance, that is, protection.
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Vacunas contra el SIDA/inmunología , Productos del Gen tat/inmunología , Vacunas Sintéticas/inmunología , Adulto , Formación de Anticuerpos , Seguridad de Productos para el Consumidor , Tolerancia a Medicamentos , Femenino , Humanos , Inmunidad Celular , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/inmunologíaRESUMEN
In the course of our studies on oxidative stress as a component of pathological processes in humans, we showed that microintrusion into cells with microcapillary and ultramicroelectrochemical detection could mimic many types of mechanical intrusion leading to an instant (0.1 s) and high (some femtomoles) burst release of H2O2. Specific inhibitors of NADPH enzymes seem to support the assumption that this enzyme is one of the main targets of our experiments. Also, human immunodeficiency virus type 1 (HIV-1) gp160 inhibits the cooperative response of uninfected T cells as well as Tat protein release by infected cells does. In this study, we analyzed in real time, lymphocyte per lymphocyte, the T-cell response following activation in relation to the redox state. We showed that the immunosuppressive effects of HIV-1 Tat and gp160 proteins and oxidative stress are correlated, since the native but not the inactivated Tat and gp160 proteins inhibit the cellular immune response and enhance oxidative stress. These results are consistent with a role of the membrane NADPH oxidase in the cellular response to immune activation.
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Productos del Gen tat/inmunología , Proteínas gp160 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Inmunosupresores/inmunología , Estrés Oxidativo/inmunología , Arsenicales/farmacología , División Celular , Inhibidores Enzimáticos/farmacología , Productos del Gen tat/genética , Productos del Gen tat/farmacología , Proteínas gp160 de Envoltorio del VIH/farmacología , Células HeLa , Humanos , Terapia de Inmunosupresión , Inmunosupresores/farmacología , NADPH Oxidasas/antagonistas & inhibidores , Oxidación-Reducción , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
The hydrothermal synthesis, single-crystal structure analysis, spectroscopic studies, and thermal stability of the compounds Ca(2)(In(1)(-)(x)()Fe(x)())(PO(4))(HPO(4))(2).H(2)O (0 = x = 1) are reported. The framework of these new phases is based on linear chains (//[101]) formed by (MO(6)) octahedra and (PO(4))/(HPO(4)) tetrahedra sharing corners. The (HPO(4)) groups and water molecules link the chains through hydrogen bonding to form layers stacked perpendicular to the c axis. The calcium cations are located between the layers and are coordinated by nine oxide anions. Crystal data: Ca(2)In(PO(4))(HPO(4))(2).H(2)O, space group C2/c (No. 15), a = 7.573(1) Å, b = 15.838(1) Å, c = 9.3126(7) Å, beta = 113.55(1) degrees; Ca(2)(In(0.5)Fe(0.5))(PO(4))(HPO(4))(2).H(2)O, C2/c (No. 15), a = 7.548(2) Å, b = 15.670(3) Å, c = 9.241(2) Å, beta = 113.62(3) degrees; Ca(2)Fe(PO(4))(HPO(4))(2).H(2)O, C2/c (No. 15), a = 7.503(2) Å, b = 15.477(2) Å, c = 9.142(1) Å, beta = 113.60(2) degrees. The phases lose two water molecules between 350 and 600 degrees C to form the series Ca(2)(In(1)(-)(x)()Fe(x)())(PO(4))(P(2)O(7)) (0 = x = 1), which are isostructural with Ca(2)V(PO(4))(P(2)O(7)). Solid state magic angle spinning (MAS) (31)P NMR of Ca(2)In(PO(4))(HPO(4))(2).H(2)O confirms two phosphorous moieties in roughly a 2:1 ratio. A CP-MAS buildup study yielded polarization transfer rates (T(IS)(-)(1)) of 2128 and 1597 s(-)(1) for the HPO(4) (-2.4 ppm) and PO(4) (-0.9 ppm) sites, respectively. A (1)H-(31)P WISE experiment indicates the presence of motional narrowing and hydrogen exchange between the water molecules and hydroxyl protons.
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The Genetics of Resistance to Infection by HIV-1 (GRIV) cohort represents 200 nonprogressor/slow-progressor (Slowprog) and 90 fast-progressor (Fastprog) HIV-1-infected patients. Using this unique assembly, we performed genetic studies on three recently discovered polymorphisms of CCR5, CCR2, and SDF1, which have been shown to slow the rate of disease progression. The increased prevalence of mutant alleles among Slowprogs from the GRIV cohort was significant for CCR5 (p < .0001) but not for CCR2 (p = .09) or SDF1 (p = . 12), emphasizing the predominant role of CCR5 as the major HIV-1 coreceptor. However, the prevalence of the CCR2 mutant allele (64I) was significantly increased among Slowprogs homozygous for wild-type CCR5 compared with Fastprogs (p = .04). The prevalence of double mutants SDF1-3'A/3'A genotypes was also increased among Slowprogs homozygous for wild-type CCR5 compared with Fastprogs (p = .05). The effects of the CCR2 and SDF1 mutations are overshadowed by the protective effects of the CCR5 deletion. Predictive biologic markers such as CD4 cell counts or viral load in the Slowprog population did not show significant differences between Slowprog groups with wild-type or mutant alleles for the three genes. Thus, our data suggest that the effects of these genes are exerted earlier in infection and no longer evident in the Slowprog of the GRIV cohort whose average duration of HIV infection is 12 years. We conclude that these genes, whose products serve as viral coreceptors or their ligands, may play a role early in infection and delay the onset of disease. However, among Slowprogs, whose duration of infection is >8 years, they are no longer influential for maintenance of their longterm nonprogression status. Other genetic determinants may be responsible for late protective effects.
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Síndrome de Inmunodeficiencia Adquirida/genética , Síndrome de Inmunodeficiencia Adquirida/inmunología , Quimiocinas CXC/genética , Infecciones por VIH/genética , Infecciones por VIH/inmunología , Polimorfismo Genético , Receptores CCR5/genética , Receptores de Quimiocina , Receptores de Citocinas/genética , Relación CD4-CD8 , Quimiocina CXCL12 , Estudios de Cohortes , Progresión de la Enfermedad , Francia , Genotipo , VIH-1 , Humanos , Inmunidad Innata/genética , Recuento de Leucocitos , Recuento de Linfocitos , Valor Predictivo de las Pruebas , Receptores CCR2RESUMEN
HIV type 1 (HIV-1) not only directly kills infected CD4(+) T cells but also induces immunosuppression of uninfected T cells. Two immunosuppressive proteins, interferon alpha (IFNalpha) and extracellular Tat, mediate this process because specific antibodies against these proteins prevent generation of suppressor cells in HIV-1-infected peripheral blood mononuclear cell cultures. Furthermore, the production of C-C chemokines in response to immune cell activation, initially enhanced by IFNalpha and Tat, ultimately is inhibited by these proteins in parallel with their induction of immunosuppression. The clinical corollary is the immunosuppression of uninfected T cells and the decline in C-C chemokine release found at advanced stages of HIV-1 infection paralleling rising levels of IFNalpha and extracellular Tat. We, therefore, suggest that IFNalpha and Tat may be critical targets for anti-AIDS strategies.
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Síndrome de Inmunodeficiencia Adquirida/inmunología , Citocinas/inmunología , Productos del Gen tat/inmunología , VIH-1/inmunología , Terapia de Inmunosupresión , Interferón-alfa/inmunología , Linfocitos T/inmunología , Citocinas/biosíntesis , Humanos , Linfocitos T/virología , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
Exposure to HIV type 1 (HIV-1) does not usually lead to infection. Although this could be because of insufficient virus titer, there is now abundant evidence that some individuals resist infection even when directly exposed to a high titer of HIV. This protection recently has been correlated with homozygous mutations of an HIV-1 coreceptor, namely CCR5, the receptor for the beta-chemokines. Moreover, earlier results already had shown that the same chemokines markedly suppress the nonsyncitial inducing variants of HIV-1, the chief virus type transmitted from person to person. CCR5 mutation, as a unique mechanism of protection, is, however, suspect because HIV-1 variants can use other chemokine receptors as their coreceptor. Moreover, recent results have established that infection can indeed sometimes occur with such mutations. Here, we report on transient natural resistance over time of most of 128 hemophiliacs who were inoculated repeatedly with HIV-1-contaminated Factor VIII concentrate from plasma during 1980-1985 before the development of the HIV blood test. Furthermore, and remarkably, 14 subjects remain uninfected to this date, and in these subjects we found homozygous CCR5 mutations in none but in most of them overproduction of beta chemokines. In vitro experiments confirmed the potent anti-HIV suppressive effect of these chemokines.
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Quimiocinas/inmunología , Infecciones por VIH/inmunología , VIH-1/aislamiento & purificación , Receptores CCR5/inmunología , Células Cultivadas , Quimiocinas/farmacología , Contaminación de Medicamentos , Factor VIII/efectos adversos , Factor VIII/uso terapéutico , Infecciones por VIH/etiología , Hemofilia A/tratamiento farmacológico , Hemofilia A/inmunología , Humanos , Inmunidad InnataRESUMEN
OBJECTIVES: To antagonize the deleterious effects of the HIV-1 toxin extracellular Tat on uninfected immune cells, we developed a new strategy of anti-HIV-1 vaccine using an inactivated but immunogenic Tat (Tat toxoid). Tat toxoid has been assayed for safety and immunogenicity in seropositive patients. METHOD: The phase I vaccine clinical trial testing Tat toxoid preparation in Seppic Isa 51 oil adjuvant was performed on 14 HIV-1-infected asymptomatic although biologically immunocompromised individuals (500-200 CD4+ cells/mm3). RESULTS: Following as many as 8 injections, no clinical defects were observed. All patients exhibited an antibody (Ab) response to Tat, and some had cell-mediated immunity (CMI) as evaluated by skin test in vivo and T-cell proliferation in vitro. CONCLUSION: These results provide initial evidence of safety and potency of Tat toxoid vaccination in HIV-1-infected individuals.
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Vacunas contra el SIDA/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Productos del Gen tat/inmunología , VIH-1/química , Vacunas contra el SIDA/efectos adversos , Vacunas contra el SIDA/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida/terapia , Síndrome de Inmunodeficiencia Adquirida/virología , Adulto , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Productos del Gen tat/efectos adversos , Productos del Gen tat/uso terapéutico , Anticuerpos Anti-VIH/inmunología , Proteína p24 del Núcleo del VIH/inmunología , VIH-1/inmunología , Humanos , Huésped Inmunocomprometido , Masculino , Proyectos Piloto , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
OBJECTIVES: To investigate which immune parameters, such as antibodies against HIV-1 specificities, or viral parameters, such as p24 antigenemia, are predictive of disease progression. STUDY DESIGN: We performed studies on serum collected from individuals exhibiting two extremes of disease evolution--67 fast progressors (FP) and 182 nonprogressors (NP)--at their enrollment. After a 1- to 2-year clinical follow-up of 104 nonprogressors after their enrollment, we could determine the best serologic predictors for disease progression. METHODS: We investigated levels of antibodies to tetanus toxoid and to HIV antigens including Env, Gag, Nef, and Tat proteins, as well as p24 antigenemia, viremia, CD4 cell count, and interferon-alpha (IFN-alpha) titers in FPs and NPs, and we correlated these data with clinical and biologic signs of progression. RESULTS: p24 Antigenemia, a marker of viral replication, and anti-Tat antibodies were highly and inversely correlated in both groups (P < .001). Furthermore, anti-p24 antibodies and low serum IFN-alpha levels were correlated to the NP versus the FP cohort. Finally, among NPs, only antibodies to Tat and not to the other HIV specificities (Env, Nef, Gag) were significantly predictive of clinical stability during their follow-up. CONCLUSION: Antibodies toward HIV-1 Tat, which are inversely correlated to p24 antigenemia, appear as a critical marker for a lack of disease progression. This study strongly suggests that rising anti-Tat antibodies through active immunization may be beneficial in AIDS vaccine development to control viral replication.
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Vacunas contra el SIDA/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Productos del Gen tat/inmunología , Anticuerpos Anti-VIH/sangre , VIH-1/inmunología , Síndrome de Inmunodeficiencia Adquirida/terapia , Síndrome de Inmunodeficiencia Adquirida/virología , Especificidad de Anticuerpos , Biomarcadores/sangre , Estudios de Cohortes , Progresión de la Enfermedad , Estudios de Seguimiento , Proteína p24 del Núcleo del VIH/sangre , Humanos , Interferón-alfa/sangre , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
Extracellular Tat can act as a viral toxin on uninfected cells of different tissues, including the CNS and the immune system, thus in order to immunize humans against Tat we have prepared a biologically inactivated but immunogenic Tat (Tat Toxoid). Tat Toxoid is not toxic in mice even at high doses. It triggers high levels of specific Tat Abs in the mouse and rabbit. Furthermore, in humans Tat Toxoid immunization was safe and induced in seronegatives persistent high levels of Tat Abs and in immunodeficient patients a significant rise of these specific Abs. Facing acute HIV-1 infection, the presence of high level of circulating Tat Abs promoted by Tat Toxoid vaccine should prevent Tat-induced immunosuppression and allow anti-HIV-1 cellular response to develop. As a consequence, early release of beta-chemokines could enhance host resistance towards HIV-1, and, in infected people, inhibit viral replication and evolution towards AIDS.
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Vacunas contra el SIDA/inmunología , Vacunas contra el SIDA/uso terapéutico , Productos del Gen tat/inmunología , Infecciones por VIH/prevención & control , Infecciones por VIH/terapia , VIH-1 , Toxoides/uso terapéutico , Vacunas contra el SIDA/efectos adversos , Animales , Formación de Anticuerpos/efectos de los fármacos , Humanos , Inmunidad Celular/efectos de los fármacos , Indicadores y Reactivos , Cinética , Ratones , Toxoides/efectos adversos , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
The Duffy Antigen Receptor for Chemokines (DARC) belongs to a family of erythrocyte chemokine receptors that bind C-X-C and C-C chemokines such as interleukin 8 (IL-8), monocyte chemoattractant protein 1 (MCP-1) and regulated-on-activation, normal T cell-expressed and -secreted (RANTES), but not macrophage inflammatory protein 1 alpha (MIP-1 alpha) or MIP-1 beta. DARC has also been identified to a receptor for malaria parasites Plasmodium vivax and Plasmodium knowlesi. In the present study, we show that HIV-1 binds to RBCs from Caucasian individuals via DARC making RBCs able to transmit HIV to peripheral blood mononuclear cells (PBMCs). Furthermore, binding of HIV-1 particles to RBCs is inhibited by treating these cells with recombinant RANTES, but not with recombinant MIP-1 alpha prior to their incubation with HIV-1. This finding suggests that RBCs may function as a reservoir for HIV-1 or as a receptor for the entry of HIV-1 into CD4-cell subsets as well as neurons or endothelial cells.