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Synthesis of nitric oxide (NO) is one of the important effector functions of innate immune cells. Although several reports have indicated mistletoe lectins induce immune cells to produce cytokines, studies regarding the activities of the lectins in the production of NO have been very limited. Here, we report on the induction of NO synthesis in a murine macrophage cell line, RAW264.7, by Korean mistletoe lectin (KML-IIU). When the macrophage cells were treated with KML-IIU in the presence of a suboptimal concentration of IFN-γ, NO production was induced in a concentration-dependent manner. Significantly higher levels of NO were induced by subchains of the KML-IIU (A and B), which have lower toxicities, as compared to the hololectin. Furthermore, expression of the inducible nitric oxide synthase (iNOS) gene was elevated in accordance with the level of NO production. When the synthase was inhibited by iNOS inhibitors (L-NIL and L-NAME), NO production was specifically reduced in a concentration-dependent manner. Our studies demonstrate that the KML-IIU and its subchains induce NO production in murine macrophage cells via activation of the iNOS gene expression, suggesting that the KML-IIU subchains may be used as an immunomodulator to enhance the effector functions of innate immune cells. [ABSTRACT FROM AUTHOR]

The sensitive detection of highly toxic botulinum neurotoxin (BoNT) from Clostridium botulinum is of critical importance because it causes human illnesses if foodborne or introduced in wounds and as an iatrogenic substance. Moreover, it has been recently considered a possible biological warfare agent. Over the past decade, significant progress has been made in BoNT detection technologies, including mouse lethality assays, enzyme-linked immunosorbent assays, and endopeptidase assays and by mass spectrometry. Critical assay requirements, including rapid assay, active toxin detection, sensitive and accurate detection, still remain challenging. Here, we present a novel method to detect active BoNTs using a Glyco-quantitative polymerase chain-reaction (qPCR) approach. Sialyllactose, which interacts with the binding-domain of BoNTs, is incorporated into a sialyllactose-DNA conjugate as a binding-probe for active BoNT and recovered through BoNT-immunoprecipitation. Glyco-qPCR analysis of the bound sialyllactose-DNA is then used to detect low attomolar concentrations of BoNT and attomolar to femtomolar concentrations of BoNT in honey, the most common foodborne source of infant botulism. [ABSTRACT FROM AUTHOR]

Rhodamine-labelled dieckol (1) synthesized through a click reaction was found to be localized in the endoplasmic reticulum (ER) of RAW 264.7 cells. Anti-inflammatory activity of compound 1 was considerably greater than that of dieckol itself. [ABSTRACT FROM AUTHOR]

Korean mistletoe lectin (KML) is composed of A and B sub-chains. The B-chain binds to cell surfaces, whereas the A-chain hinders translation because it is a RIP (ribosome inactivating protein) inducing apoptosis. Although KML has various biological and immunological activities, its potential use in cancer therapy or as an adjuvant therapy is limited by its toxicity to normal cells. This study was conducted to determine whether the B-chain of KML (KML-B) has immunoadjuvant activity and cytotoxicity activity. To evaluate the immunomodulatory activities of B chain KML, in vitro experiments employing bone marrow-derived dendritic cells (BMDCs) were performed. Dendritic cells (DCs) are a unique group of white blood cells that are able to capture and process antigens for presentation to T cells, which constitute primary immune response. In the present study, KML-B was found to be non-cytotoxic to BMDCs. Furthermore, the expressions of co-stimulatory molecules (CD40, CD80, CD86, and MHC II) and the secretions of cytokines (IL-1β, IL-6, IL-12p70, and TNF-α) were increased in BMDCs by KML-B. In addition, other indicators (antigen-uptake and CCR7 expression) of BMDC maturation were changed by KML-B, and the ability of KML-B to enhance various functions by BMDCs was found to be dependent on TLR4 expression. Moreover, BMDCs matured by KML-B induced naïve CD4+ T cell differentiation toward Th1 cells directly and indirectly. These experiments confirm that KML-B exhibits potent immunomodulatory properties and suggest that KML-B be considered a potential dendritic cell-based cancer therapy and immunoadjuvant. [ABSTRACT FROM AUTHOR]

The article presents a study on the improved isolation methods for mucosal leukocytes from small and large intestines of rats. It states that reliable protocols for isolating intraepithelial lymphocytes (IEL) and lamina propria lymphocytes (LPL) from small intestine and LPL from large intestine are being established. It is found that modified isolation protocol enables the collection of mucosal immune cells from the rats' intestines and identifies functions of IEL and LPL in those intestines.