Biology subjects

Sova, M.

Publications and source records attributed to Sova, M..

7 recordsLinked to original sources

bioRxiv2026

A fusion Cell-Permeable C16orf74 Peptide Selectively Disrupts Calcineurin-NFAT Interaction and Inhibits T-cell Activation Without Cytotoxicity

Calcineurin (Cn) is a protein phosphatase that initiates T-cell activation by dephosphorylating the transcription factor NFAT, driving its nuclear translocation and the transcription of immune-related genes. While clinical immunosuppressants like Cyclosporine A (CsA) potently inhibit Cn, they completely block its catalytic site, leading to non-specific inhibition and severe off-target toxicity. Selectively targeting the specific protein-protein interaction (PPI) between Cn and NFAT presents a safer therapeutic strategy. We previously identified the C16orf74 (C16) peptide as a high-affinity Cn-NFAT PPI inhibitor; however, its utility in cellular systems is restricted by poor membrane permeability. In this study, we evaluated cell-penetrating peptide (CPP) conjugates of C16 with an N-terminus transactivator of transcription (TAT) and polyarginine (R11) to enable efficient intracellular delivery. Structural modeling, fluorescence polarization displacement, and pull-down assays confirmed that the CPP-C16 conjugates retain the ability to compete with an NFAT-derived peptide and bind Cn. Fluorescence microscopy demonstrated efficient intracellular entry of TAT-C16 and R11-C16 in mammalian cells, and effective inhibition of NFAT nuclear translocation and attenuation of downstream NFAT-dependent transcriptional activity of the IL-2 gene in human T cells at concentrations of 10 {micro}M or lower. Crucially, unlike CsA, the CPP-C16 peptides exhibited minimal cytotoxicity even at high concentrations of up to 50 {micro}M, establishing a potential safe therapeutic window. These findings establish CPP-C16 conjugates as effective, cell-permeable, and non-toxic inhibitors of the Cn-NFAT signaling axis, providing the basis for the development of PPI-directed immunosuppressants.

bioengineering↗

bioRxiv2026

Dual Immune Checkpoint and Cytokine Receptor Modulation by an Engineered Human CTLA-4/IL-10 Bispecific Fusion Protein

Bispecific fusion proteins represent a unique strategy for developing precision therapeutics. By linking functional domains from distinct proteins, these biomolecules can engage multiple targets, enhancing both therapeutic efficacy and safety. Unlike bispecific antibodies, low-molecular-weight fusion proteins offer distinct advantages, including reduced immunogenicity and superior tissue penetration due to their relatively compact size and structure. Such a profile is particularly valuable in managing complex inflammatory diseases, where modulating multiple pathways is required to impart an effective anti-inflammatory effect. Among the various regulators of immune signaling, the cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and interleukin-10 (IL-10) play imperative roles in immune suppression through their interactions with CD80/86 and IL-10R, respectively. While Fc-fused CTLA-4 is a clinically approved drug (e.g., Abatacept), the clinical development of IL-10 has been hampered by unpredictable immunostimulatory side effects. Here, we engineered a bispecific fusion protein linking the extracellular domain of CTLA-4 to IL-10. We successfully expressed the protein in E. coli as an N-terminal GST-tagged variant and refolded it from the inclusion bodies. Additionally, we achieved soluble expression of an Fc-tagged variant in mammalian CHO cells. Both origins demonstrated binding to their cognate receptors, CD80 and IL-10R. Finally, the fusion protein demonstrated a T cell-inhibitory effect by reducing Interferon-{gamma} (IFN{gamma}) secretion levels in an in vitro human Virus-Specific T cells (VSTs) model. This innovative protein engineering offers a promising strategy for addressing unmet clinical needs in autoimmune and inflammatory diseases.

bioengineering↗

bioRxiv2025

Real-Time Sensing of Food Spoilage Using a Recombinant mVenus-Tolles FRET pH Biosensor

Monitoring food spoilage is essential for enhancing food safety and reducing waste. pH changes serve as a valuable indicator of microbial activity, and real-time pH monitoring can provide an accurate and non-invasive indication of food spoilage. The pHlameleon chimera proteins were developed for pH sensing by Forster resonance energy transfer (FRET) and were extensively used in various biomedical applications. Herein, we evaluate the mVenus-Tolles as a FRET-based biosensor for detecting pH changes as a proxy for food spoilage. The protein was fused to an N-terminal vesicle-nucleating peptide (VNP) tag and recombinantly expressed and purified to homogeneity. Experimental validation demonstrated pH-responsive FRET signal in an array of buffers as well as in a complex food matrix such as chickpea paste, correlating with increasing acidity and microbial growth in food. These findings suggest that this protein-based FRET biosensor holds promise for safe integration into food or packaging for real-time freshness monitoring.

bioengineering↗

bioRxiv2025

Psoriasin inhibits microbial growth in food by metal sequestering

Food spoilage is a significant economic and environmental concern, and it is estimated that [~]30% of fresh food is destroyed due to food spoilage between harvest to consumer. Current food preservatives are chemicals that are associated with various health risks and often have limited effectiveness under certain conditions like pH and temperature. Consequently, theres a growing need to develop effective, natural, and economical food preservatives. Herein, we studied the natural protein psoriasin as a potential food preservative. Psoriasin is naturally secreted in the oral cavity and has an effective and validated antimicrobial activity which makes it a potentially effective and safe protein-based food preservative. Indeed, our preliminary results show promising antimicrobial activity of the recombinant protein against food-related microbial organisms in vitro and in various food types. In addition, it is recombinantly expressed at high levels, which could set a cost-effective manufacturing process. These results set psoriasin as a safe and effective natural food preservative, addressing consumer demand for healthier food options and reducing food waste.

biochemistry↗

bioRxiv2024

Enhancing Collagen Biosynthesis in Mammalian Cells Through Hypoxia-Mimetic Prolyl Hydroxylase Inhibition

Collagen, the most abundant protein in the extracellular matrix of mammalian cells, is extensively needed in various biotechnological and therapeutic applications, such as tissue engineering and regeneration, cosmetics, and cultivated meat. Despite the increasing demand for natural collagen from non-animal sources, it is mainly produced from animal connective tissues. Recent research has highlighted that under hypoxia, the activation of the hypoxia-inducible factor (HIF) leads to enhanced collagen type I biosynthesis. However, under normal oxygen conditions, HIF activity is downregulated by the HIF-prolyl hydroxylase (PHD) enzyme. We, therefore, hypothesized that inhibiting PHD could elevate HIF transcriptional activity and enhance collagen biosynthesis under normoxia. Our study demonstrates that inhibiting PHD using exogenous small molecules boosts HIF activity and upregulates the key enzymes, collagen prolyl 4-hydroxylases and lysyl hydroxylases, resulting in up to 29-fold increase in collagen type I in embryonic mouse fibroblast NIH/3T3 cells. These findings suggest that targeting PHD can effectively enhance collagen production in mammalian cells. Therefore, modulating key protein signaling pathways presents a promising strategy for enhancing the production of high-yield natural collagen.

cell biology↗

bioRxiv2024

Anti-fungal recombinant psoriasin effectively inhibits Candida albicans growth on denture base

Oral candidiasis leading to denture stomatitis is a fungal infection resulting from unregulated growth and adhesion mainly of Candida albicans onto acrylic denture base. Once the biofilm is formed, it is immune resistant and mainstay treatments involve toxic chemical antifungal agents or mechanical cleaning techniques, both offer limited efficacy. Consequently, there is an urgent need for more effective and safer therapeutic approaches. While biological modalities are expanding in general medicine, the exploration of protein-based therapeutics in dental medicine remains limited. This research evaluates the inhibitory effect of recombinantly expressed psoriasin on the growth of Candida albicans on polymethyl methacrylate denture bases. Psoriasin, also known as S100-A7, has shown promise in treating microbial skin infections, and its natural presence in saliva makes it a promising candidate for treating oral microbial infections. Our findings indicate that psoriasin exhibits a strong, dose-dependent inhibition of Candida albicans growth. Further, we incubated a polymethyl methacrylate denture base within the psoriasin solution. Notably, immersing the denture base in the solution completely eradicated fungal growth. Our research utilizes natural antifungal proteins within biomedical devices like denture bases, suggesting psoriasin as a safe alternative to chemical antifungals in dental medicine.

biochemistry↗

bioRxiv2023

Nature-Inspired Peptide of MtDef4 C-terminus Tail Enables Protein Delivery in Mammalian Cells

Cell-penetrating peptides hold great promise as versatile tools for the intracellular delivery of therapeutic agents. Various peptides have originated from natural proteins with antimicrobial activity. In this study, we investigated the mammalian cell-penetrating properties of a 16-residue peptide derived from the C-terminus tail of the Medicago truncatula defensin protein, with the sequence GRCRHGFRRRCFCTTHC. We evaluated the ability of this peptide to penetrate multiple types of cells. Our results demonstrate that the peptide efficiently penetrates mammalian cells within minutes and at a sub-micromolar concentration. Moreover, upon N-terminal fusion to the fluorescent protein GFP, the peptide efficiently delivers the GFP into the cells. Despite its remarkable cellular penetration, the peptide has only a minor effect on cellular viability, making it a promising candidate for the development of a cell-penetrating peptide, with potential therapeutic applications.

cell biology↗