Factores virales y celulares que afectan la transmisión vertical del HIV-1 / Viral and cellular factors affecting vertical transmission of HIV-1

Distintos factores virales y celulares pueden condicionar la susceptibilidad a la infección por el HIV-1. La inmunidad innata constituye la primera línea de defensa contra el virus jugando un papel fundamental en la etapa temprana de la transmisión del HIV-1 previo al desarrollo del sistema inmune adaptativo. Está constituida por elementos celulares como las células NK, granulocitos, macrófagos, células dendríticas, etc. y solubles como quimioquinas, defensinas y proteínas de unión a azúcares (lectinas) capaces de ejercer actividad antiviral. Se ha demostrado que variaciones genéticas de componentes de la respuesta inmune pueden modificar el riesgo de transmisión del HIV-1 y desarrollo de sida. Entre ellos se encuentran primordialmente los co-receptores del virus CCR5 y CXCR4, y las proteínas del complejo mayor de histocompatibilidad clase I y II. Además, características biológicas y evolutivas del HIV-1 pueden modificar el riesgo de la transmisión viral.

Viral and cellular factors may condition susceptibility to HIV-1 infection. Innate immunity represents the fist line of defense against the virus with mayor relevance at initial stages of HIV-1 transmission prior to the development of the adaptative immune system. Cellular components, such as, NK cells, granulocytes, macrophages, dendritic cells, etc and soluble factors like chemokines, defensins and sugar binding proteins (lectins) have antiviral activity. Genetic variations of immune response components can modify the risk of HIV-1 transmission and AIDS development. These mainly include viral co-receptors CCR5 and CXCR4 and HLA class I and II. Furthermore, biologic and evolutionary characteristics of HIV-1 can modify the risk of viral transmission.

Morphological Differences of the Wound Healing in Secretory Leukocyte Protease Inhibitor Knockout Mice / 체질인류학회지

Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor with anti-microbial properties found in mucosal fluids. At the tissue level, the ability of this 12kDa protein is to counteract the excessive degradation of functional and structural proteins such as collagen and fibronectin. Impaired healing states are characterized by excessive proteolysis and often bacterial infection, leading to the hypothesis that SLPI may have a role in this process. To investigate the role of SLPI in skin how it contributes to tissue repair, we have generated mice null for the gene encoding SLPI (Slpi), which show impaired cutaneous wound healing with increased inflammation. For the purpose of this, we have performed wound experiment in skin tissue with morphometrical analyses, immunohistochemistry, and Rnase protection assay. From these analyses, the results were that delayed healing in KO mice wounds compared to that of WT, prolonged inflammatory phase and increased TGF-beta1 in KO wounds, and lower mechanical properties in KO wounds. Taken together, SLPI may play a cruical role in cutaneous wounds healing especially in matrix reorganization that suggests the development as a clinical drug for wound healing.

Regulation of Mucin and Non-Mucin Secretions and Gene Expression by Retinoic Acid in Human Airway Epithelium / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Airway hypersecretion is a frequent feature of several respiratory tract diseases including rhinitis, sinusitis, and otitis media. Efforts are being made in several laboratories to elucidate mechanisms involved in the regulation of secretion. There are several factors which modulate expression of the secretory phenotype, such as retinoic acid (RA), triiodothyronine, steroid, and extracellular matrix. We have been interested in elucidating the role of retinoids in regulating differentiation of mucin and non-mucin secretions. MATERIALS AND METHODS: Retinoic acid was removed from the culture media of normal human tracheobronchial epithelial cells grown in the air-liquid interface cultures. The effects on cell phenotype and mucin, lysozyme (LZ), and the secretory leukocyte protease inhibitor (SLPI) secretion and gene expression were examined. RESULTS: Removal of RA from the media induced squamous differentiation and caused a drastic decrease in mucin secretion and a decrease in expression of the mucin genes, MUC2 and MUC5AC. Lysozyme and SLPI secretions were increased in RA-depleted cultures. Paradoxically, LZ mRNA was decreased, while the SLPI mRNA levels were increased. A most intriguing finding was the paradoxical response of LZ to RA-depletion. The reason for this apparant incongruity between mRNA and protein levels is currently under investigation. CONCLUSION: Our studies show that RA is an important factor for mucous differentiation.