A 51-year-old man was referred to our hospital for the further examination of main pancreatic duct interruption. Imaging findings showed a 25-mm-diameter mass lesion located in the pancreatic head. Endoscopic ultrasonography (EUS)-guided fine-needle aspiration (FNA) was performed on the mass. Cytology suggested adenocarcinoma, but the histological diagnosis was not confirmed. We made a comprehensive diagnosis of resectable pancreatic cancer. The mass shrank after preoperative adjuvant chemotherapy, and the patient underwent surgery. The final pathological diagnosis was type 2 autoimmune pancreatitis (AIP). Two years after surgery, AIP had not recurred in the remaining pancreas.

Hepatocyte growth factor (HGF) serves key roles in cell motility, proliferation and immunoregulatory functions. However, the effect of HGF on macrophages is unclear. The present study aimed to elucidate the effect of HGF on the phenotypic alterations of intestinal lamina propria mononuclear cells (lPMcs). colitis was induced in a mouse model using dextran sodium sulfate (dSS). Subsequently, lPMcs were isolated from the mice with chronic colitis and the expression levels of cytokine-encoding genes in the lPMcs were determined. cd11b-positive macrophages isolated from lPMcs were cultured with HGF, and alterations in the levels of M1 or M2 markers were evaluated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and flow cytometry. In addition, the cytokine levels were assessed using rT-qPcr and eliSa. HGF shifted the phenotype of macrophages from M1 to M2-like, as determined by increased mrna expression levels of arginase-1, cd206 and il-10, and reduced mrna expression levels of cd86 and il-6 in mice with dSS-induced colitis. Moreover, HGF could ameliorate dSS-induced colitis owing to its immunosuppressive effect on immune cells. These findings indicated that HGF treatment may not only promote the regeneration of epithelial cells but also lead to tissue repair by phenotypic alteration of M1 macrophages to M2-like macrophages.

<b><i>Introduction:</i></b> Sprayable wound dressings containing hydrophobized microparticles (hMPs) are characterized by strong adhesiveness. We examined the effect of hMPs derived from Alaska pollock gelatin on endoscopic submucosal dissection (ESD) ulcers. <b><i>Methods:</i></b> (1) In an in vivo model of miniature swine gastric ESD, gastric ulcers were created by ESD and then sprayed with hMPs or untreated followed by microscopic examination. (2) In an ex vivo ESD model of resected stomach, a pinhole-shaped perforation was created on the ESD ulcer of resected stomach; hMPs were then sprayed on the perforation; and air leakage and intragastric pressure were measured. (3) In an in vivo duodenal ESD model of miniature swine, duodenal artificial ESD ulcers with pinhole-shaped perforation were examined; ulcers were classified into hMPs-sprayed and nonsprayed groups, and inflammation in the intrinsic muscle layer and serosa were compared between the groups. <b><i>Results:</i></b> (1) Histological observation of submucosal tissues showed a decreased number of invading inflammatory cells in hMP-sprayed tissues compared with the control in miniature swine gastric ESD (<i>p</i> &#x3c; 0.05). In addition, the rates of anti-alpha smooth muscle actin and type I collagen positivity were significantly lower in the hMPs group than in the control group (<i>p</i> &#x3c; 0.05). (2) Intragastric pressure could not be measured in the nonsprayed group, whereas no air leakage was observed in the sprayed group when pressurized up to 26 mm Hg in the resected stomach model. (3) The sprayed group showed suppressed inflammation of the intrinsic muscular layer and serosa in both cases compared with the nonsprayed group in miniature swine duodenal ESD (<i>p</i> &#x3c; 0.05). <b><i>Conclusions:</i></b> Sprayable, tissue-adhesive hMPs are a promising medical material for intraoperative and postoperative treatment of ESD-induced wound via anti-inflammation and strong adhesiveness.