The immunomodulatory glycan LNFPIII initiates alternative activation of murine macrophages in vivo

Abstract

Summary The early pathogen–macrophage interactions that help drive macrophage maturation towards classically or alternatively activated are largely unknown. To examine this question we utilized the immunomodulatory glycan Lacto‐N‐fucopentaose III (LNFPIII), which contains the Lewis X (LeX) trisaccharide, to activate murine peritoneal macrophages in vivo. Because LNFPIII is known to induce anti‐inflammatory responses, we asked if LNFPIII stimulation of macrophages in vivo initiates alternative activation events such as upregulation of Arginase 1, Ym1, FIZZ‐1, MGL‐1 or macrophage mannose receptor (MMR). Examination of peritoneal exudate cells from mice 20 hr post‐LNFPIII injection demonstrated increased Arginase 1 activity, at the mRNA and protein levels, coincident with undetectable inducible nitric oxide synthase expression or nitric oxide production. In addition to Arginase 1, Ym1 expression was also significantly upregulated at 20 and 48 hr after LNFPIII exposure in vivo. However, the expression of FIZZ‐1, MGL‐1, and MMR was not changed in these macrophages. In an attempt to determine activation requirements for functional activity, we adoptively transferred antigen‐pulsed, in vivo LNFPIII activated macrophages into naïve recipients and found that they were capable of triggering recipient T cells to secrete elevated levels of interleukin (IL)‐10 and IL‐13 compared to mice receiving control macrophages. Together, these data demonstrate that upregulation of expression of Arginase 1 and Ym1 occur very early in activation of macrophages, and can be independent of other alternatively activated (AA) macrophage markers. Importantly, these early events appear to be IL‐4/IL‐13‐independent in our model. In the future we hope to determine if upregulation of these initial AA maturational events is sufficient for these macrophages to exert immunoregulatory activity in vivo.

<i>Survivin</i> promoter rs9904341 polymorphism is associated with tumor stage and grade in patients with bladder cancer

“…Previous studies reported that the expression of survivin was significantly increased in patients with a higher tumor grade of urinary tract malignancies [27][28][29][30][31][32]. Swana et al shown that bladder cancer patients with higher survivin expression have a shorter time to recurrence [13].…”

Immunomodulatory Glycan Lacto-N-Fucopentaose III Requires Clathrin-Mediated Endocytosis To Induce Alternative Activation of Antigen-Presenting Cells

“…The Lewis x trisaccharide is abundantly expressed on schistosome egg antigens and is the terminal trisaccharide of the LNFPIII pentasaccharide that we have used to study pathogen/self glycan activation of innate immune responses (10,26). LNFPIII neoglycoconjugates (LNFPIII-NGC) comprised of multiple (7 to 10) LNFPIII moieties conjugated via linker-spacer technology to carrier molecules have been employed to determine how LNFPIII/ Lewis x activates and induces alternative activation of APCs and drives anti-inflammatory responses in vivo.…”

“…Bone marrow-derived dendritic cells (BMDCs) were obtained by flushing bone marrow cells in RPMI 1640 and culturing the cells with 20 ng/ml of granulocyte-macrophage colony-stimulating factor (GM-CSF; PeproTech, Rocky Hill, NJ) essentially as described previously (10). On days 3 and 5, fresh medium containing GM-CSF was added to the cells.…”

“…In this regard, we and others demonstrated that glycans found on pathogens in human milk and in certain foods are capable of inducing alternative activation of APCs (9)(10)(11). Glycans on glycoproteins and glycolipids are known to play important roles not only for binding of glycoproteins to receptors on APCs but also in increasing phagocytosis (12)(13)(14)(15).…”

“…The Lewis x trisaccharide is also found within the structure of the human milk pentasaccharide lacto-N-fucopentaose III (LNFPIII), and neoglycoconjugates (NGC) with multiple molecules of LNFPIII (7 to 10) linked to a carrier molecule via linker spacer technology (LNFPIII-NGC) are immune modulatory in vivo, showing dramatic therapeutic effects on autoimmune diseases and metabolic disease (26)(27)(28)(29). Further, LNFPIII-NGCs induce AA macrophages and facilitate expansion of IL-10-producing B1-B cells in vivo (10,30).…”