SPECIFICITY AND SIGNIFICANCE OF LECTIN RECEPTORS IN BREAST CARCINOMA

Eight lectins were used to study 100 cases of breast carcinoma and 56 cases of non-carcinoma breast tissues by lectin affinity histochemical method. The results showed that Bandeirasa Simplicifolia (BSL) and Peanut agglutinin (PNA) had higher positive rates in breast carcinoma than both normal breast and benign lesions (P<0.005). The positive deposit in malignant lesions was mainly located in cytoplasm, while in non-malignant lesions, it was almost lined along the lumen of glands and small ducts (P<0.005). The authors think that expression of PNA-receptor in the cytoplasm might be associated with the mechanism that the tumor could escape from immune attack. Comparison analysis on the normal breast indicated that PNA affinity histoche-mistry would be useful to the understanding of the metabolism of β-D-galactosyl-N-acetyl-D-galactosa-mine during the development of normal breast and histological origin of breast carcinoma.

LABELING AND QUANTITATIVE ANALYSIS OF SIX LECTIN RECEPTORS OF INTRACRANIAL GLIOMAS

The distribution of six lectin receptors, WGA, RCA-1, LCA, PSA, PNA and SBA in 111 human gliomas, 8 human normal brain tissues and 11 reactive hyperplasia of astrocytes was observed by means of avidin-biotin-peroxidase technique. Their grays were also quantified with the image analysis instrument. The results showed that WGA and RCA-1 might be used as markers for distinguishing well-ifferentiated astrocytomas from the reactive hyperplasia of astrocytes especially the reactivity of astrocytes had a specific feature with RCA-1. The difference in quantities of WGA, RCA-1, LCA, PSA receptors between astrocytomas, ependymomas and oligodendrogliomas, medulloblastomas might conduce to the diagnosis and classification. For astrocytomas, it was also showed that a quantity of LCA and PSA receptors was correlated with the degree of cell differentiation. Therefore, they can be used as valuable markers of the differentiation of astrocytomas.

Research progress of pattern recognition receptors and chronic periodontitis

Pattern recognition receptor(PRR)is a kind of sensor which is mainly expressed on the surface of innate immune cells.It can recognize pathogen related molecular patterns(PAMPs)or damage related molecular patterns(DAMPs).The innate immune system uses pattern recognition receptors to recognize pathogenic microorganisms in periodontal tissues and transmit signals to downstream pathways in time,thus triggering immune responses and then eliminating them.PRR has many family members,including toll like receptor family(TLRs),C-type lectin receptor family(CLRs),retinoic acid induced gene I(RIG-I)like receptor family(RLRs)and nucleotide binding oligomer domain(NOD)like receptor family(NLRs).Among them,RLRs are cytoplasmic receptors that recognize dsRNA from RNA viruses and have little association with chronic periodontitis.In this paper,the classification and structure of TLRs,CLRs,NLRs and the role of signal transduction pathway in chronic periodontitis are reviewed.In order to enrich the pathogenesis of periodontitis,provide new ideas for the treatment and prevention of chronic periodontitis.

Involvement of Dectin-2 in the Innate Inflammatory Response Triggered by Influenza Virus Hemagglutinin

C-type lectin receptors (CLRs) are representative pattern recognition receptors that recognize microbial polysaccharides expressed on antigen-presenting cells. In the present study, we carried out further detailed analysis on the involvement of Dectin-2, a CLR that senses high mannose polysaccharide, in innate immune responses induced by influenza virus hemagglutinin (HA). Treatment of HA with periodate or PNGase F induced lower interleukin (IL)-12p40 secretion by conventional dendritic cells (DCs) compared with the untreated group. In contrast, treatment with O-glycosidase did not affect cytokine production. Green fluorescent protein expression in canonical Dectin-2-transducing cells was approximately 3% - 12% following HA stimulation, except with the A/H1N1pdm09 subtype HA. This expression was markedly reduced in cells possessing mutated amino acids in the carbohydrate recognition domain of Dectin-2, especially following stimulation with HA derived from the A/H3N2 subtype. Interferon (IFN)-α production from CD11c+Siglec-H+PDCA-1+ plasmacytoid DCs was significantly increased in Dectin-2 knockout mice compared with wild-type mice upon stimulation with HA except for the B/Yamagata lineage HA. These results suggested that Dectin-2 is involved in initiating inflammatory responses via mannose polysaccharide on HA. However, other mechanisms may function in the antiviral response, including the type I IFN axis.

C-type lectin receptor-induced NF-κB activation in innate immune and inflammatory responses

The C-type lectin receptors （CLRs） belong to a large family of proteins that contain a carbohydrate recognition domain （CRD） and calcium binding sites on their extracellular domains. Recent studies indicate that many CLRs, such as Dectin-1, Dectin-2 and Mincle, function as pattern recognition receptors （PRRs） recognizing carbohydrate ligands from infected microorganisms. Upon ligand binding, these CLRs induce multiple signal transduction cascades through their own immunoreceptor tyrosine-based activation motifs （ITAMs） or interacting with ITAM-containing adaptor proteins such as FcRy. Emerging evidence indicate that CLR-induced signaling cascades lead to the activation of nuclear factor kappaB （NF-KB） family of transcriptional factors through a Syk- and CARD9-dependent pathway（s）. The activation of NF-κB plays a critical role in the induction of innate immune and inflammatory responses following microbial infection and tissue damages. In this review, we will summarize the recent progress on the signal transduction pathways induced by CLRs. and how these CLRs activate NF-κB and contribute to innate immune and inflammatory responses.

Tailoring the Immune Microenvironment of Dendritic Cells by Targeting C-type Lectin Receptor

Background:The C-type lectin receptor(CLR)expressed by DCs participates in the recognition and capture of various glycosylated self-antigens and pathogens.Understanding the diversity of the CLR expressed by DCs,as well as their role in maintaining the balance between Th1-type and Th2-type cytokines would promote the understanding of the pathogenesis of many diseases including preeclampsia(PE).Methods:DCs were isolated from the placentae of healthy women who underwent normal pregnancies and infected with a CLR lentiviral(LV)vector for gene overexpression or small interfering RNA(siRNA)knockdown.DCs were cocultured with T-cells and EVCTs,and five groups were established as follows:Group 1-DCs from healthy women who underwent normal pregnancies,Group 2-DCs from women with preeclampsia(PE),Group 3-DCs infected with empty LV vectors,Group 4-DCs infected with a CLR LV vector for gene overexpression,and Group 5-DCs infected with a CLR LV vector for siRNA knockdown.The levels of Th1-and Th2-type cytokines were measured in all groups.Results:The levels of Th1-type cytokines were significantly higher in women with PE than in those with normal pregnancies(P<0.05).Among these five groups,the Th1/Th2 ratio of Group 5 was highest(P<0.05).There was no difference in the Th1/Th2 ratio between Groups 1 and 3.Conclusions:There was a Th1/Th2 imbalance in women with PE displaying Th1-type immunity.CLR-overexpressing DCs showed a diminished capacity to polarize na?ve T-cells into Th1 effector cells.The impaired Th1 response in DCs was rescued by CLR siRNA knockdown.In conclusion,DCs may affect the production of cytokines and the migration of T-cells through CLR-mediated signaling pathways during pregnancy.