RESUMEN
The V1/V2 domain of the HIV-1 gp120 envelope protein has been shown to contribute to viral cell tropism during infection and also to viral recognition by neutralizing monoclonal antibodies. However, this domain has been poorly investigated. Carbohydrates have been demonstrated to dramatically influence immune reactivity of antisera to viral glycoprotein antigens. In this study, DNA sequences coding for V1/V2 domains from HIV-1 primary isolates of three subtypes (A, B, and C) were subcloned into a secretion vector and used to transfect CHO cells that are able to achieve the glycosylation of proteins. The structure of purified recombinant V1/V2 proteins was tested using two anti-V1/V2 monoclonal antibodies directed against either a linear or a conformational and glycosylation-dependent epitope (8.22.2 and 697-D). Serum or saliva of 14/82 seropositive patients with anti-V1/V2 reactivity demonstrated good recognition of the recombinant proteins. Deglycosylation of the recombinant proteins was found to increase the reactivity of the serum IgG to the clade A and C but not to clade B V1/V2 domain demonstrating that the recognition of glycosylation sites by serum IgG is clade dependent. When considering SIgA from parotid saliva, deglycosylation of all recombinant proteins tested decreased the reactivity, suggesting that glycosylation plays an important role in the recognition of V1/V2 domain target epitopes by this class of antibodies. In conclusion, these results suggest the influence of carbohydrate moieties on the specificity of the antibodies to the V1/V2 domain produced during HIV infection and the potential importance of viral glycans in vaccine responses after mucosal administration.
Asunto(s)
Epítopos de Linfocito B/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Inmunoglobulina A Secretora/inmunología , Inmunoglobulina G/inmunología , Adulto , Anciano , Secuencia de Aminoácidos , Animales , Células CHO , Cricetinae , Cricetulus , Epítopos de Linfocito B/metabolismo , Femenino , Glicosilación , Proteína gp120 de Envoltorio del VIH/metabolismo , Humanos , Inmunoglobulina A Secretora/análisis , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Proteínas Recombinantes/inmunología , Saliva/inmunología , Alineación de Secuencia , Suero/inmunologíaRESUMEN
The development of a preventive vaccine against human immunodeficiency virus type-1 (HIV-1) provides hope for control of the pandemic over the coming years. Nevertheless, it is clear that one of the greatest difficulties in achieving this vaccine is the high mutation rate of the virus, which enables it to evade the host's immune response. The production of neutralizing antibodies (NAb) against the HIV-1 envelope proteins is believed to play an important role in controlling the infection and in providing effective protection following vaccination. Several studies have shown that the V1/V2 domain of the HIV-1 gp120 envelope protein is involved in viral tropism during infection, in masking conserved neutralizing epitopes, in the conformational changes occurring after coreceptor binding, and in NAb induction. Nonetheless, this domain has been poorly investigated. However, because the V1/V2 domain is highly glycosylated, numerous studies have determined the influence of carbohydrates on NAb production. The present review focuses on the importance of NAb directed against epitopes of the variable regions, mainly V1/V2, their importance in protecting against HIV-1 infection, and the role these regions play in evading the immune response. Lastly, we will discuss the importance of NAb in the search for an effective vaccine against HIV-1.
Asunto(s)
Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Anti-VIH/biosíntesis , Antígenos VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Evasión Inmune/inmunología , Fragmentos de Péptidos/inmunología , Secuencia de Aminoácidos , Anticuerpos Neutralizantes/inmunología , Reacciones Antígeno-Anticuerpo , Epítopos/química , Epítopos/genética , Epítopos/inmunología , Genes env , Glicosilación , Anticuerpos Anti-VIH/inmunología , Antígenos VIH/química , Antígenos VIH/genética , Proteína gp120 de Envoltorio del VIH/química , Proteína gp120 de Envoltorio del VIH/genética , VIH-1/genética , Humanos , Evasión Inmune/genética , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Conformación Proteica , Procesamiento Proteico-Postraduccional , Estructura Terciaria de ProteínaRESUMEN
Neutralizing activity of secretory immunoglobulin A (S-IgA) directed against the V1/V2 domain of HIV-1 was studied in parotid saliva of HIV-1- infected patients in Colombian and French cohorts. Purified V1/V2-specific S-IgA antibodies were found to neutralize clades A, B and C primary isolates in five out 76 and 82 patients from each cohort, respectively. These results suggest that neutralizing S-IgA antibodies targeting the V1/V2 domain may provide protection against HIV-1 infection in vivo and may be beneficial in mucosal vaccines.
Asunto(s)
Anticuerpos Neutralizantes/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Inmunoglobulina A Secretora/inmunología , Saliva/inmunología , Estudios de Cohortes , Colombia , Femenino , Francia , Proteína gp120 de Envoltorio del VIH/inmunología , Humanos , Masculino , Fragmentos de Péptidos/inmunología , Saliva/virologíaRESUMEN
We studied the IZUMO gene 9 coding exons sequence in four groups of patients including those with fertilization failure by conventional IVF. We observed in our populations two combinations of four polymorphisms that appeared to be preferentially linked (CGG-CG and TAA-TT) without any significant difference between different genotype repartitions.