Calpain Small Subunit Mediated Secretion of Galectin-3 Regulates Traction Stress.

The complex regulation of traction forces (TF) produced during cellular migration remains poorly understood. We have previously found that calpain 4 (Capn4), the small non-catalytic subunit of the calpain 1 and 2 proteases, regulates the production of TF independent of the proteolytic activity of the larger subunits. Capn4 was later found to facilitate tyrosine phosphorylation and secretion of the lectin-binding protein galectin-3 (Gal3). In this study, recombinant Gal3 (rGal3) was added to the media-enhanced TF generated by capn4-/- mouse embryonic fibroblasts (MEFs). Extracellular Gal3 also rescued defects in the distribution, morphology, and adhesive strength of focal adhesions present in capn4-/- MEF cells. Surprisingly, extracellular Gal3 does not influence mechanosensing. c-Abl kinase was found to affect Gal3 secretion and the production of TF through phosphorylation of Y107 on Gal3. Our study also suggests that Gal3-mediated regulation of TF occurs through signaling pathways triggered by ß1 integrin but not by focal adhesion kinase (FAK) Y397 autophosphorylation. Our findings provide insights into the signaling mechanism by which Capn4 and secreted Gal3 regulate cell migration through the modulation of TF distinctly independent from a mechanosensing mechanism.

Correlation Between Nasal Allergy and the Number of Eosinophils in Adenoid Tissue.

To study adenoid tissue eosinophilia in allergic rhinitis. A single-centre clinical case-control prospective study with 66 subjects enrolled for the study after taking written informed consent from all the participants. All patients underwent adenoidectomy with histopathological evaluation of adenoid tissue samples for eosinophils. 36 patients (cases) with Symptoms for Allergic Rhinitis (SFAR) score indicative of allergic rhinitis. 30 patients (control) with SFAR scores not indicative of allergic rhinitis. All patients were evaluated for serum absolute eosinophil count and total serum immunoglobulin E (Ig-E). There was a significant relationship between allergic rhinitis and serum Ig-E levels using the Kruskal-Wallis rank sum test amongst case and control groups with a p-value of 0.031. Pathologically examined slides of adenoid tissue eosinophil count per 10 random high power fields in these patients showed significant results with a p-value of 0.002432, via the Kruskal-Wallis rank sum test. Statistical analysis, shows that adenoid tissue eosinophil count and serum Ig-E levels can somewhat predict the presence of clinical features of allergic rhinitis. Based on several similar studies with similar results, allergic rhinitis can be gauged with adenoid tissue histopathology and routine evaluation should be considered as a standard of care.