There is an increasing interest in cationic polymers as important constituents of non-viral gene delivery vectors. In the present study, we developed a versatile synthetic route for the production of covalent polymeric conjugates consisting of water-soluble depolymerized chitosan (dCS; MW 6–9 kDa) and low molecular weight polyethylenimine (PEI; 2.5 kDa linear, 1.8 kDa branched). dCS-PEI derivatives were evaluated based on their physicochemical properties, including purity, covalent bonding, solubility in aqueous media, ability for DNA condensation, and colloidal stability of the resulting polyplexes. They were complexed with non-integrating DNA vectors coding for reporter genes by simple admixing and assessed in vitro using liver-derived HuH-7 cells for their transfection efficiency and cytotoxicity. Using a rational screening cascade, a lead compound was selected (dCS-Suc-LPEI-14) displaying the best balance of biocompatibility, cytotoxicity, and transfection efficiency. Scale-up and in vivo evaluation in wild-type mice allowed for a direct comparison with a commercially available non-viral delivery vector (in vivo-jetPEI). Hepatic expression of the reporter gene luciferase resulted in liver-specific bioluminescence, upon intrabiliary infusion of the chitosan-based polyplexes, which exceeded the signal of the in vivo jetPEI reference formulation by a factor of 10. We conclude that the novel chitosan-derivative dCS-Suc-LPEI-14 shows promise and potential as an efficient polymeric conjugate for non-viral in vivo gene therapy.

Background and Purpose: Antibodies targeting cell surface receptors are considered to enable highly selective therapeutic interventions for immune disorders and cancer.Their biological profiles are found, generally, to represent the net effects of antibody-target interactions. The former therapeutic anti-integrin αLβ2 antibody efalizumab seems to defeat this paradigm by eliciting, via mechanisms currently unknown, much broader effects than would be predicted based on its target specificity. Experimental Approach:To elucidate the mechanisms behind these broad effects, we investigated in primary human lymphocytes in vitro the effects of anti-αLβ2 antibodies on the expression of αLβ2 as well as unrelated α4 integrins, in comparison to Fab fragments and small-molecule inhibitors. Key Results:We demonstrate that anti-αLβ2 mAbs directly induce the internalization of α4 integrins. The endocytotic phenomenon is a direct consequence of their antibody nature. It is inhibited when monovalent Fab fragments or small-molecule inhibitors are used. It is independent of crosslinking via anti-Fc mAbs and of αLβ2 activation. The cross-modulatory effect is unidirectional and not observed in a similar fashion with the α4 integrin antibody natalizumab. Conclusion and Implications:The present study identifies endocytotic crossmodulation as a hitherto unknown non-canonical functionality of anti-αLβ2 antibodies. This cross-modulation has the potential to fundamentally alter an antibody's benefit risk profile, as evident with efalizumab. The newly described phenomenon may be of relevance to other therapeutic antibodies targeting cluster-forming receptors. Thus, pharmacologists should be cognizant of this action when investigating such antibodies.

The delivery of nucleic acids relies on vectors that condense and encapsulate their cargo. Especially nonviral gene delivery systems are of increasing interest. However, low transgene expression levels and limited tolerability of these systems remain a challenge. The improvement of nucleic acid delivery using depolymerized chitosan–polyethylenimine DNA complexes (dCS‐PEI/DNA) is investigated. The secore complexes are further combined with chitosan‐based shells and functionalized with polyethylene glycol (PEG) and cell penetrating peptides. This modular approach allows to evaluate the effect of functional shell components on physicochemical particle characteristics and biological effects. The optimized ternary complex combines a core‐dCS‐linear PEI/DNA complex with a shell consisting of dCS‐PEG‐COOH, which results in improved nucleic acid encapsulation, cellular uptake and transfection potency in human hepatoma HuH‐7cells and murine primary hepatocytes. Effects on transgene expression are confirmed in wild‐type mice following retrograde intrabiliary infusion. After administration of only 100 ng complexed DNA, ternary complexes induced a high reporter gene signal for three days. It is concluded that ternary coreshell structured nanoparticles comprising functionalized chitosan can be used for in vitro andin vivo gene delivery.

Hydroxychloroquine (HCQ) is a quinoline derivate used for the treatment of malaria and rheumatoid disorders. During early phases of the SARS-CoV2 (COVID-19) pandemic, preliminary and later not substantiated reports suggested that HCQ might benefit COVID-19 patients. This had sparked a worldwide and rapidly rising demand for HCQ drug products. Consequently, patients with pre-existing rheumatic diseases in Switzerland were confronted with an acute drug shortage.<br><br>We have therefore designed, produced and characterized a generic HCQ drug formulation. The proposed HCQ formulation can be manufactured by using a minimal number of operation steps (mixing, wet granulation, sieving, blending, compression) and readily available pharmaceutical excipients.<br><br>HCQ tablets were manufactured by granulation of the active pharmaceutical ingredient (API), blending with the external phase and compaction using a non instrumented single punch tablet press. Analytics and identification of the API was performed by a combination of NMR, ESI-MS, FTIR and HPLC. HCQ tablets met the quality criteria for an immediate release HCQ dosage form.<br><br><div>We hope that free access to non-proprietary protocols covering analytical procedures, formulation design, and manufacturing instructions for HCQ tablets will help to bridge existing and future supply chain gaps.</div><div><br></div><div><br></div>