At low levels, RANTES serves to promote the recruitment of leukocytes to the site of inflammation, while at high levels, CCL5 stops acting as a chemokine and has direct immunostimulatory and proapoptotic activities (68). the molecular and immunoregulatory mechanisms induced by this parasite. is usually a worldwide-distributed parasitic flatworm that causes fasciolosis, a zoonotic disease that affects mainly livestock and causes significant economic losses worldwide (1). In addition, the World Health Organization (WHO) estimates that around 2.5 million people are infected around the world and several millions are at risk (1). Like other helminths, modulates the host immune response by inducing potent polarized Th2 and regulatory T cell immune responses and by downregulating the production of Th1 cytokines (2C5). This immunoregulated environment favors the differentiation of regulatory T cells (3), the alternative activation of macrophages (5), and the modulation of the activity of both dendritic cells (DCs) and mast cells (2, 6C8). Helminths express carbohydrate-containing glycoconjugates on their surface and they release glycan-rich excretion/secretion products that can be very important in their life cycles and pathology, since they can participate in immune escape (9). In this context, we have recently explained that glycans structures produced by participate in the modulation of DC maturation and mediate the production of IL-10 and IL-4 during contamination (10). Parasite glycans are recognized by the immune system through the conversation of C-type lectin receptors (CLRs), a large family of calcium-dependent glycan-binding proteins Melanocyte stimulating hormone release inhibiting factor that present structural homology in their carbohydrate acknowledgement domain (11). Several reports have highlighted the role of CLRs in mediating the internalization of parasite glycoconjugates and cell-surface signaling, leading to a modulation of the host immune response (12C14). Macrophage Gal/GalNAc lectin (MGL), also known as CLEC4A or CD301, is a type II transmembrane protein expressed on professional antigen-presenting cells (15, 16). MGL displays a remarkable specificity for Melanocyte stimulating hormone release inhibiting factor terminal (20), (21), and (22). Furthermore, it has been proposed that MGL2+ dermal DCs are specialized in the induction of Th2 responses both in allergy and helminth-infection models (22). Given that glycans modulate DC maturation inducing a Th2/regulatory-polarized immune response (2C5) and our group has previously recognized the Tn antigen hEDTP expressed on glycoconjugates (23), the simplest mucin type can modulate the TLR2-induced maturation of human monocyte-derived DCs (mo-DCs) in a process mediated by hMGL by upregulating the production of IL-10 and TNF. Furthermore, we show that mMGL2+ CD11c+ F4/80lo cells are recruited to the peritoneum of infected mice. Interestingly, these cells express the regulatory cytokines IL-10, TNF, and TGF and a variety of regulatory markers. The results presented here constitute the first statement about the participation of mMGL2+ CD11c+ in the growth of Th2/regulatory-immune responses and in the suppression of Th1 polarization during an helminth contamination, suggesting a potential role of MGL in the immunomodulation induced by and contribute to a better understanding of the molecular and immunoregulatory mechanisms induced by this parasite. Materials and Methods Ethics Statement Mouse experiments were carried Melanocyte stimulating hormone release inhibiting factor out in accordance with strict guidelines from your National Committee on Animal Research (Comisin Nacional de Experimentacin Animal, CNEA, http://www.cnea.org.uy, National Legislation 18.611, Uruguay) according to the international statements on animal use in biomedical research from your Pan American Health Business and WHO. Adult worms were collected from bovine livers during the routine work of a local abattoir (Frigorfico Carrasco) in Montevideo (Uruguay). Protocols were approved by the Uruguayan Committee on Animal Research (Comisin Honoraria de Experimentacin Animal, CHEA Protocol Figures: 071140-001822-11 and 071140-000143-12). Mice Six- to eight-week-old female BALB/c mice were obtained from DILAVE Laboratories (Uruguay). Animals were kept in the animal house (URBE, Facultad de Medicina, UdelaR, Uruguay) with water and food supplied were obtained from the Melanocyte stimulating hormone release inhibiting factor bile ducts of bovine livers, washed in phosphate-buffered saline (PBS) pH 7.4, then mechanically disrupted and sonicated. After Melanocyte stimulating hormone release inhibiting factor centrifugation at 40,000??for 60?min, supernatants were collected and dialyzed against PBS. The obtained lysate (FhTE) was quantified and stored at ?80C. The endotoxin levels were determined by using the Limulus Amebocyte Lysate kit Pyrochrome (Associates of Cape Cod). Protein preparations showed very low levels of endotoxins and were not able to induce DC maturation on their own. The concentration.
