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use of synthetic antimicrobial peptides to facilitate the our laboratory identified molecules having the ability to boost the effectiveness of anti-infective agents.
these molecules have themselves anti-infective properties (antibacterial and antifungal) and are able to increase the effectiveness of antibiotics already commercially available.
We study the effect of different synthetic peptides characterized in our laboratory. at micromolar concentrations, these cationic linear peptides have lytic properties against gram-positive bacteria, teChnology fungi and yeasts; whereas they are not lytic for the host cells and can stimulate neutrophils by inducing entry of extracellular calcium. they are able to destabilize the membranes of microorganisms, thereby allowing the entry of the antibiotic to reach its intracellular target. Preliminary studies have shown the synergistic effect of these peptides with antibiotics. for example one of the identified molecule acts at a concentration of 10 mM and has a synergistic action at 4 microM with existing antibiotics. for instance, the voniconazol antibiotic acts at a concentration of 0.5μg/ml. We cut to a dose of 0.125μg/ml by adding 4 mM of the peptides identified at last but not least, besides the therapeutic aspect, the peptides of interest identified by the laboratory can be used in a diagnostic frame (prognostic biomarkers) : the presence or not of the natural molecule in the patient will allow the prediction whether the patient may respond to anti- so far in vitro experiments using a combination of peptides of the collection comprising voriconazole, linezolid, amoxicillin and metronidazole showed synergistic properties of the peptides decreasing twice or three times the concentration of antibiotic. this also presents a double interest: reduce the toxicity, very frequent with these drugs at very narrow therapeutic index in some patients aDVantages (particularly the patients severely affected with liver and kidney dysfunctions consecutive to the Moreover, this combination authorizes the action of antibiotics in question, even when the patient does not have the proteins required for their action.
aPPliCations new treatment of bacterial or fungal infections We contemplate the application for a patent on the invention and are willing to enter a collaborative partnership with one or more industrials partners interested in the study aiming at identifying the in close relation with chemists our laboratory has the ability to insert these peptides in coating materials for dental prostheses, catheters, surgical instruments or dressings. the emergence of a large number of microorganisms resistant to conventional antibiotics is a major public health problem. as long as gram-positive infections are concerned, several therapeutic options are developed. the urgent need concerns drugs effective against pathogenic bacteria and fungi, gram- [1]. the stakes are high because the number of immunocompromised patients is increasing due to the increased number of patients treated with immunosuppressive drugs (organ transplant recipients of all, autoimmune diseases and systemic inflammatory .). the resistance of microorganisms to antibiotics is highly dependent on the integrity of the outer membrane, this structure acts as a permeable barrier and effectively prevents many antimicrobial baCKgrounD agents to reach their intracellular targets [2]. because the lPs plays a crucial role in the stability of the outer membrane and is present in many pathogens, most of the implemented strategies consist in agents able to target it. these are the PaMs which by their amphipathic and cationic nature are able to bind lPs, destabilize the outer membrane and kill the target cell by mechanisms that are not yet fully understood [3-5]; thus it was reported that while some PaMs were added to a concentration below its MiC, they are capable of altering the permeability of the outer membrane thus rendering the bacteria sensitive to antibiotics that are inactive in the presence of an intact membrane [ 6, 7].
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