IADR Abstract Archives
Effect of matriptase on mast cell accumulation after UV exposure
Objectives: The extracellular matrix (ECM) is subject to perpetual remodelling, and aberrant degradation during tumourigenesis can lead to tumour invasion and metastasis. Pericellular proteases can play a role in ECM regulation and modelling. Matriptase is a membrane bound serine protease expressed in most epithelial tissues under physiologic conditions, and is also expressed in cells of the immune system including mast cells. Matriptase expression has been linked to oral cancer progression. Mast cells are best known for their immune functions, however there is evidence that mast cells may play a crucial role in tumourigenesis. Mast cell activation is also triggered by PAR-2, an endogenous substrate of matriptase. The aim of this study is to determine whether lack of matriptase has an effect on lymph node and dermal mast cell accumulation after chronic exposure to UV radiation in mice.
Methods: We exposed matriptase hypomorphic and wild type C57BL/6 female mice to a bank of UVA and UVB emitting fluorescent tubes (250mJ/cm2 and accompanying UVA to mimic solar UV) for 25 weeks. Concurrently a control group of matriptase hypomorphic and wild type C57BL/6 female mice were raised for 25 weeks in the absence of UV treatment. Sections of dorsal trunk lymph nodes were stained in an H&E and toluidine blue staining protocol allow for identification of mast cells. Intergroup comparisons in mast cell density were analysed using one-way ANOVA with multiple comparisons with Bonferroni’s correction (Prism 7; GraphPad Software Inc, San Diego, USA).
Results: A four-fold reduction in reduction in lymph mast cell density (MCD) was observed between irradiated hypomorphic and wild type mice. A three-fold increase in dermal MCD and a five-fold reduction in lymph node MCD was observed between hypomorphic irradiated and non-irradiated mice.
Conclusions: Lack of matritptase appears to enhance mast cell accumulation in skin, and inhibit accumulation in lymph nodes.
Methods: We exposed matriptase hypomorphic and wild type C57BL/6 female mice to a bank of UVA and UVB emitting fluorescent tubes (250mJ/cm2 and accompanying UVA to mimic solar UV) for 25 weeks. Concurrently a control group of matriptase hypomorphic and wild type C57BL/6 female mice were raised for 25 weeks in the absence of UV treatment. Sections of dorsal trunk lymph nodes were stained in an H&E and toluidine blue staining protocol allow for identification of mast cells. Intergroup comparisons in mast cell density were analysed using one-way ANOVA with multiple comparisons with Bonferroni’s correction (Prism 7; GraphPad Software Inc, San Diego, USA).
Results: A four-fold reduction in reduction in lymph mast cell density (MCD) was observed between irradiated hypomorphic and wild type mice. A three-fold increase in dermal MCD and a five-fold reduction in lymph node MCD was observed between hypomorphic irradiated and non-irradiated mice.
Conclusions: Lack of matritptase appears to enhance mast cell accumulation in skin, and inhibit accumulation in lymph nodes.