New strategic insights into managing fungal biofilms

Fungal infections have dramatically increased in the last decades in parallel with an increase of populations with impaired immunity, resulting from medical conditions such as cancer, transplantation or other chronic diseases. Such opportunistic infections result from a complex relationship between fungi and host, and can range from self-limiting to chronic or life-threatening infections. Modern medicine, characterized by a wide use of biomedical devices, offers new niches for fungi to colonize and form biofilm communities. The capability of fungi to form biofilms is well documented and associated with increased drug tolerance and resistance. In addition, biofilm formation facilitates persistence in the host promoting a persistent inflammatory condition. With a limited availability of antifungals within our arsenal, new therapeutic approaches able to address both host and pathogenic factors that promote fungal disease progression, i.e. chronic inflammation and biofilm-formation, could represent an advantage in the clinical setting. In this paper we discuss the antifungal properties of Myriocin, Fulvic Acid and Acetylcholine in light of their already known anti-inflammatory activity and as candidate dual action therapeutics to treat opportunistic fungal infections

In vivo utjecaj imunosupresije u majki za vrijeme trudnoće na imunosni sustav novorođenčadi

When used in pregnancy, immunosuppressants can cross the placental barrier and enter foetal circulation, possibly affecting the immune system of the foetus. This study evaluated the immune function in eight children born by mothers with connective tissue diseases who received immunosuppressants (cyclosporine A or dexamethasone) during pregnancy and in six babies from mothers with similar diseases, but who did not receive any treatment. Judging by the cytokine production of interleukin-2 and interferon-γ in peripheral blood mononuclear cells stimulated by phorbol-myristate-acetate (PMA) and ionomycin, immunosuppressive drugs given for rheumatic disorders during pregnancy do not induce significant immunosuppression in babies.Imunosupresivni lijekovi davani za vrijeme trudnoće mogu proći placentalnu barijeru i ući u cirkulaciju fetusa, s mogućim utjecajem na njegov imunosni sustav. U radu je praćena imunosna funkcija kod osmero djece rođene od majki s bolestima vezivnog tkiva, koje su tretirane za vrijeme trudnoće imunosupresivnim lijekovima (ciklosporin A ili deksametazon) i kod osmero novorođenč adi rođene od majki sa sličnim bolestima, ali koje nisu bile tretirane. Imunosupresivni lijekovi primijenjeni za vrijeme trudnoće kod majki koje boluju od reumatskih bolesti ne izazivaju značajniju imunosupresiju u novorođenčadi praćenu nastajanjem citokina, interleukina 2 i interferona γ_ u perifernim mononuklearnim krvnim stanicama pod djelovanjem forbol-miristat-acetata (PMA) i ionomicina

Anti-biofilm Activity of Antibody Directed Against Surface Antigen Complement Receptor 3-Related Protein-Comparison of Candida Albicans and Candida Dubliniensis

Candida species (spp.) are a part of the normal human microbiota. Candida dubliniensis mostly colonizes the oral cavity and/or respiratory tract (Mahelová and Růžička 2017), especially in HIV-infected individuals (Coleman et al.1997; Sullivan et al.2004; Wahab et al.2014), while Candida albicans is a common inhabitant of the gastrointestinal tract, urogenital tract and oral cavity (Sardi et al.2013; Höfs, Mogavero and Hube 2016). Candidiasis is the most common global fungal infection (Sardi et al.2013). Candida albicans has been isolated in more than 50% of candidiasis; however, the number of non-albicans spp. able to cause serious candidiasis has increased in recent years (Yapar 2014; Pu et al.2015; Sandhu et al.2017). Although C. dubliniensis is phylogenetically very similar to C. albicans, it differs in some genes, especially those coding for virulence-associated proteins. Candida dubliniensis lacks more than 168 genes characteristic of its ‘yeast-cousin’ C. albicans (Jackson et al.2009), the majority of them encoding proteins related to the yeast-to-hyphae transition, tissue invasion or biofilm development (Moran et al.2004; Jackson et al.2009; Moran, Coleman and Sullivan 2012). Moreover, C. dubliniensis manifests a higher predisposition to develop resistance to fluconazole (Sullivan et al.1995; Moran, Coleman and Sullivan 2012; Jordan et al.2014). On the other hand, both C. albincans and C. dubliniensis are able to form a biofilm (Sullivan et al.2004; Borghi et al.2014). Adherence is the first and most crucial step in biofilm development, and various surface antigens participate in this process (Chaffin 2008; Gow and Hube 2012; Hebecker et al.2014). CR3-RP (complement receptor 3-related protein) is one of the cell surface antigens of Candida spp. with functional and structural similarity to the human complement receptor 3 (CR3) expressed on neutrophils, macrophages and monocytes. CR3-RP has been demonstrated to bind human complement fragment iC3b and to mediate leukocyte diapedesis (Heidenreich and Dierich 1985; Bujdáková et al.1997). Additionally, CR3-RP seems to be an important immunogenic mannoprotein participating in adhesion and biofilm development (Bujdáková et al.2008, 2010). A fragment of CR3-RP was sequenced (DINGGGATLPQ), and according to this sequence, CR3-RP was categorized into the DING protein family (named after DINGGG N termini) (Bujdáková et al.2008; Bernier 2013). Some other surface proteins contributing to biofilm development have been described, such as Eap protein, the Als protein family, the Hwp1 or MP65 proteins (Gomez et al.1996; Nailis et al.2010; Finkel and Mitchell 2011; Araújo, Henriques and Silva 2017). Additionally, antibodies generated after the immunization of animals with some of the above proteins seems to be promising in tools focused on fighting yeast infections (Fujibayashi et al.2009; Mishra, Ali and Shukla 2015; Torosantucci et al.2017). Recent studies showed that antibodies targeting Als3 (Coleman et al.2009), MP65 (De Bernardis et al.2007) or another 42.7 kDa unnamed surface antigen in the Candida cell wall (Mishra, Ali and Shukla 2015) decreased adhesion and biofilm formation

Biofilms formed by Candida albicans bloodstream isolates display phenotypic and transcriptional heterogeneity that are associated with resistance and pathogenicity

Background: Candida albicans infections have become increasingly recognised as being biofilm related. Recent studies have shown that there is a relationship between biofilm formation and poor clinical outcomes in patients infected with biofilm proficient strains. Here we have investigated a panel of clinical isolates in an attempt to evaluate their phenotypic and transcriptional properties in an attempt to differentiate and define levels of biofilm formation.<p></p> Results: Biofilm formation was shown to be heterogeneous; with isolates being defined as either high or low biofilm formers (LBF and HBF) based on different biomass quantification. These categories could also be differentiated using a cell surface hydrophobicity assay with 24 h biofilms. HBF isolates were more resistance to amphotericin B (AMB) treatment than LBF, but not voriconazole (VRZ). In a Galleria mellonella model of infection HBF mortality was significantly increased in comparison to LBF. Histological analysis of the HBF showed hyphal elements intertwined indicative of the biofilm phenotype. Transcriptional analysis of 23 genes implicated in biofilm formation showed no significant differential expression profiles between LBF and HBF, except for Cdr1 at 4 and 24 h. Cluster analysis showed similar patterns of expression for different functional classes of genes, though correlation analysis of the 4 h biofilms with overall biomass at 24 h showed that 7 genes were correlated with high levels of biofilm, including Als3, Eap1, Cph1, Sap5, Plb1, Cdr1 and Zap1.<p></p> Conclusions: Our findings show that biofilm formation is variable amongst C. albicans isolates, and categorising isolates depending on this can be used to predict how pathogenic the isolate will behave clinically. We have shown that looking at individual genes in less informative than looking at multiple genes when trying to categorise isolates at LBF or HBF. These findings are important when developing biofilm-specific diagnostics as these could be used to predict how best to treat patients infected with C. albicans. Further studies are required to evaluate this clinically.<p></p&gt

Synthesis of Amphiphilic Hydantoin-based Universal Peptidomimetics as Antibiotic Agents

Three model hydantoin-based universal peptidomimetics are designed and synthetized. Their preferred amphiphilic -turn conformation was assessed by molecular modeling and NMR experiments, and their antibacterial acivity tasted against Gram positive and Gram negative bacteria strains, demostrating that these compounds could be a captivating class of antibiotic to fight emergent drug resistanc