Hydrogel-forming microneedle arrays made from light-responsive materials for on-demand transdermal drug delivery

We describe, for the first time, stimuli-responsive hydrogel-forming microneedle (MN) arrays that enable delivery of a clinically-relevant model drug (ibuprofen) upon application of light. MN arrays were prepared using a polymer prepared from 2-hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA) by micromolding. The obtained MN arrays showed good mechanical properties. The system was loaded with up to 5% (w/w) ibuprofen included in a light-responsive 3,5-dimethoxybenzoin conjugate. Raman spectroscopy confirmed the presence of the conjugate inside the polymeric MN matrix. In vitro, this system was able to deliver up to three doses of 50 mg of ibuprofen upon application of an optical trigger over a prolonged period of time (up to 160 hours). This makes the system appealing as a controlled release device for prolonged periods of time. We believe that this technology has potential for use in “on-demand” delivery of a wide range of drugs in a variety of applications relevant to enhanced patient care

Characterisation of eppin function: expression and activity in the lung

Eppin is a serine protease inhibitor expressed in male reproductive tissues. In this study we have demonstrated novel sites of eppin expression in myeloid and epithelial cell lines with further confirmation in primary myeloid cell types. Using immunohistochemistry and Western blotting, eppin was detected in the lungs of patients with Acute Respiratory Distress Syndrome and Cystic Fibrosis lung disease. Expression of eppin in monocytic cells was unaffected by stimulation with TLR agonists, cytokine stimulation and hormone receptor agonist stimulation. However, upregulated expression and secretion of eppin was observed following treatment of monocytes with epidermal growth factor (EGF). Incubation of recombinant eppin with monocytic cells resulted in significant inhibition of lipopolysaccharide (LPS)-induced chemokine production. Furthermore, eppin inhibited LPS- induced NF-κB activation by a mechanism which involved accumulation of phosphorylated IκBα. In an in vivo model of lung inflammation induced by LPS, eppin administration resulted in decreased recruitment of neutrophils to the lung with a concomitant reduction in the levels of the neutrophil chemokine MIP-2. Overall, these results suggest a role for eppin outside of the reproductive tract and that eppin may have a role in the innate immuneresponse in the lung

Characterisation of small protease inhibitors as potential therapeutics

Neutrophil-derived serine proteases provide one of the first lines of defense against infection in innate immunity. However, in some disease states, the activity of these proteases becomes excessive and prolonged and so novel lead molecules with the potential to inhibit the excessive activity of these proteases in disease states are constantly being sought. In the current study, three proteinaceous protease inhibitors were chosen for characterisation. The specificity of the Escherichia coli trypsin inhibitor (ecotin) was modulated by site-directed mutagenesis studies; the elastase and cathepsin G-like inhibitor (eglin C) from Hirudo medicinalis was used as a positive control recombinant protein and the functional characteristics of the epididymal protease inhibitor (eppin) were examined. Eppin's anti-bacterial activity had been partially characterised but beyond this, very little functional information was available for the protein. Composed of the Whey acidic protein (WAP) and Kunitz inhibitor motifs, eppin was postulated to have anti-protease and immunomodulatory properties. Expression vectors were constructed for eppin and each of its consensus inhibitor domains and recombinant proteins were subsequently expressed in and purified from E. coli cells. The proteins all had elements of a-helix and p-sheet in their secondary structure, deduced by circular dichrosim (CD) analysis. Eppin and its domains were found to kill E. coli cells via a mechanism of permeabilisation of bacterial membranes resulting in uncoupling of respiratory electron transport but the two domains were required to achieve maximal effect. The Kunitz domain inhibited human neutrophil elastase to a similar extent as the intact protein but the.WAP domain exhibited no such activity. In a model of lipopolysaccharide (LPS)-induced inflammation in a monocytic cell line, eppin was shown 'to inhibit the expression of three pro-inflammatory cytokines. The mechanism of inhibition, in the case of one of the cytokines, was via down-regulation of transcription ofthe cytokine.EThOS - Electronic Theses Online ServiceGBUnited Kingdo