Mouse Colony Stimulating Factor 3

Impaired wound healing is a persistent clinical problem which has been treated with mixed results. Studies aimed at elucidating the mechanism of impaired wound healing have focused on small cohorts of genes which leave an incomplete picture of the wound healing process. We aimed to investigate impaired wound healing via a comprehensive panel of angiogenic/inflammation-related genes and wound closure kinetics with and without the application of extracorporeal shock wave therapy (ESWT), which has been demonstrated to improve wound healing. Full-thickness skin from the dorsal surface of "normal" (BALB/c) and "impaired" (db (+)/db (+)) mice was excised, and wound margin tissue was harvested 2, 7, and 10 days post injury. A separate, but identical wound model was established over 40 days in order to measure wound closure kinetics. Over time, the normal non-ESWT treated wounds exhibited varying patterns of elevated expression of 25-30 genes, whereas wounds with impaired healing displayed prolonged elevated expression of only a few genes (CXCL2, CXCL5, CSF3, MMP9, TGF-alpha). In response to ESWT, gene expression was augmented in both types of wounds, especially in the expression of PECAM-1; however, ESWT had no effect on wound closure in either model. In addition, multiple doses of ESWT exacerbated the delayed wound healing, and actually caused the wounds to initially increase in size. These data provide a more complete picture of impaired wound healing, and a way to evaluate various promising treatments.

Exposure to silver nanoparticles (AgNP) used in consumer products carries potential health risks including increased susceptibility to infectious pathogens. Systematic assessments of antimicrobial macrophage immune responses in the context of AgNP exposure are important because uptake of AgNP by macrophages may lead to alterations of innate immune cell functions. In this study we examined the effects of exposure to AgNP with different particle sizes (20 and 110 nm diameters) and surface chemistry (citrate or polyvinlypyrrolidone capping) on cellular toxicity and innate immune responses against Mycobacterium tuberculosis (M.tb) by human monocyte-derived macrophages (MDM). Exposures of MDM to AgNP significantly reduced cellular viability, increased IL8 and decreased IL10 mRNA expression. Exposure of M.tb-infected MDM to AgNP suppressed M.tb-induced expression of IL1B, IL10, and TNFA mRNA. Furthermore, M.tb-induced IL-1 beta, a cytokine critical for host resistance to M.tb, was inhibited by AgNP but not by carbon black particles indicating that the observed immunosuppressive effects of AgNP are particle specific. Suppressive effects of AgNP on the M.tb-induced host immune responses were in part due to AgNP-mediated interferences with the TLR signaling pathways that culminate in the activation of the transcription factor NF-.B. AgNP exposure suppressed M.tb-induced expression of a subset of NF-.B mediated genes (CSF2, CSF3, IFNG, IL1A, IL1B, IL6, IL10, TNFA, NFKB1A). In addition, AgNP exposure increased the expression of HSPA1A mRNA and the corresponding stress-induced Hsp72 protein. Up-regulation of Hsp72 by AgNP can suppress M.tb-induced NF-kappa B activation and host immune responses. The observed ability of AgNP to modulate infectious pathogen-induced immune responses has important public health implications.