RESUMEN
Hot water extract from biomass of heterotrophic mutant green alga Parachlorella kessleri HY1 (Chlorellaceae) was deproteinised, and three polysaccharidic fractions were obtained by preparative chromatography. The low-molecular fraction (1.5 × 104g mol-1) was defined mainly as branched O-2-ß-xylo-(1â3)-ß-galactofuranan where xylose is partially methylated at O-4. Two high-molecular fractions (3.05 × 105 and 9.84 × 104g mol-1) were complex polysaccharides containing α-l-rhamnan and xylogalactofuranan parts in different ratios. The polysaccharides were well soluble in hot water and, upon cooling, tended to self-segregate. Immunomodulatory activities of the obtained fractions were preliminary tested using ELISA, FACS and ImmunoSpot kits. The polysaccharides increased the TNF-α production in melanoma bearing mice with much higher intensity than in healthy mice. This was in agreement with the FACS results on T and B cells indicating their possibly secondary activation by innate immunity cells.
Asunto(s)
Linfocitos B/efectos de los fármacos , Chlorophyta/química , Factores Inmunológicos/farmacología , Polisacáridos/farmacología , Linfocitos T/efectos de los fármacos , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Linfocitos B/inmunología , Linfocitos B/patología , Secuencia de Carbohidratos , Regulación de la Expresión Génica/efectos de los fármacos , Factores Inmunológicos/química , Factores Inmunológicos/aislamiento & purificación , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-2/genética , Interleucina-2/inmunología , Interleucina-4/genética , Interleucina-4/inmunología , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Melanoma/inmunología , Melanoma/patología , Metilación , Ratones , Ratones Endogámicos C57BL , Peso Molecular , Extractos Vegetales/química , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Cultivo Primario de Células , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/patología , Solubilidad , Linfocitos T/inmunología , Linfocitos T/patología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Agua , Xilosa/química , Xilosa/aislamiento & purificaciónRESUMEN
New foods and natural biological modulators have recently become of scientific interest in the investigation of the value of traditional medical therapeutics. Glucans have an important part in this renewed interest. These fungal wall components are claimed to be useful for various medical purposes and they are obtained from medicinal mushrooms commonly used in traditional Oriental medicine. The immunotherapeutic properties of fungi extracts have been reported, including the enhancement of anticancer immunity responses. These properties are principally related to the stimulation of cells of the innate immune system. The discovery of specific receptors for glucans on dendritic cells (dectin-1), as well as interactions with other receptors, mainly expressed by innate immune cells (e.g., Toll-like receptors, complement receptor-3), have raised new attention toward these products as suitable therapeutic agents. We briefly review the characteristics of the glucans from mycelial walls as modulators of the immunity and their possible use as antitumor treatments.