Accurate characterization of the amino acid sequence and post translational modifications (PTMs) of monoclonal antibodies (mAbs) is essential for evaluating product quality. Peptide mapping through bottom-up LC/MS analysis is a key methodology for this purpose. While trypsin is commonly the first choice for mAb digestion, it typically yields high but incomplete sequence coverage. As a result, supplementary endoproteases such as Asp-N, chymotrypsin, Glu-C or Lys-C are often employed to enhance coverage. In this report, we evaluated another endoprotease, Tryp-N, which serves as an effective alternative to trypsin for mAb analysis. The sequence coverages achieved for bevacizumab, cetuximab, NISTmAb, and trastuzumab with Tryp-N were comparable to that of trypsin, and the combination of both enzymes slightly improved overall sequence coverage. Notably, both trypsin and Tryp-N generated identical peptides beside the N- and C-terminal ends. The presence of a basic amino acid at opposite ends of the peptide often resulted in complementary sequence coverage of the MS2 of the same peptide sequences. These complementary ion series can be leveraged for precise localization of PTMs, as demonstrated in detail for deamidation, and oxidation sites as well as single amino acid variants (SAVs).

Osteosarcoma (OS) is an aggressive bone cancer that most commonly affects children and young adults. OS exhibits a high degree of genomic complexity, as well as cellular plasticity, and dynamic transcriptional regulation is suggested to contribute to treatment resistance and metastasis. Cell lines are well characterised as models to advance our knowledge on OS biology. HOS and U2OS cells have increased invasiveness and higher migratory ability compared with MG63. In this study, we employed a tandem array of consensus transcription factor response elements (catTFREs) proteomic approach to characterise transcription factor (TF) regulatory networks related to OS aggressiveness. We mapped 7355 proteins and enriched 504 TFs and coregulators. When we integrated proteomics with cell line specific gene expression, H3K27ac marked enhancers and chromatin accessibility, we classified the TFs and coregulators common for HOS and U2OS and specific for the individual cell lines. We demonstrate that RUNX2 and MYBL2 are specifically enriched in HOS and U2OS. RUNX2 and MYBL2 exhibited an increase in expression in metastatic compared to primary OS tumours and may be linked to cell aggressiveness. ETV5, TBX15, and USF1 were among TFs specific to the lower migratory cell line MG63 and these genes were more expressed in primary OS tumours. Our analysis provides a comprehensive understanding of the transcriptional drivers that shape OS cell line regulatory landscapes and may have implications as markers pending further validation.

BackgroundTear fluid (TF) is a protein-rich fluid reported to reflect pathophysiological changes in several neurodegenerative diseases, including Alzheimer's disease. TF proteins are increasingly being considered as putative biomarker candidates to help in the diagnosis of disease. However, little information is available on TF protein changes in persons with mild cognitive impairment (MCI).ObjectiveThis study aimed to determine alterations in the expression of proteins in TF collected from persons with MCI compared with cognitively healthy controls.MethodsWe analyzed data from 54 study participants, including 34 controls (mean age, 71 years; mean Mini-Mental State Examination [MMSE] score ± standard deviation, 28.9 ± 1.4) and 20 persons with MCI (mean age, 71 years; mean MMSE score, 27.1 ± 1.9). All participants underwent cognitive, neurological, and ophthalmological examinations. TF was collected using Schirmer strips and evaluated using mass spectrometry-based proteomics and label-free quantification.ResultsThe expression of 33 TF proteins involved in oxidative stress, clearance mechanism, cytoskeleton stability, and inflammation were altered in persons with MCI compared with controls (p ≤ 0.05).ConclusionsOur findings reveal that numerous cellular stress-related biomarker candidate proteins are upregulated or downregulated in the TF of persons with MCI, a condition that may increase the risk of developing AD or other memory disorder. These data encourage TF protein studies in neurodegenerative diseases and TF provides an additive source of biomarkers for early diagnostics of memory diseases.

Introduction Efficient cardiac excitation-contraction (EC) coupling depends on the proper spreading of electrical activity. To facilitate the propagation of depolarizing action potentials within cardiomyocytes, specialized sarcolemmal invaginations, known as transverse tubules (t-tubules), form an interconnected network. BIN1 (Bridging Integrator 1), a banana-shaped like protein of the BAR (BIN1-amphiphysin-Rvs) family, regulates t-tubule biogenesis and the localization of critical proteins such as Cav1.2, ensuring efficient Ca2+ transients. HCN4, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel, is crucial for cardiomyocyte excitability and generates a slow depolarizing If (“funny”) current, which enables the heart to generate its intrinsic pacemaker activity. Objective This work aims to define the subcellular distribution of BIN1 and HCN4 in cardiomyocytes, to evaluate their interaction, and to study the functional impact of BIN1 on HCN4 electrophysiology. We explore the potential role of BIN1 as a scaffold regulating HCN4 trafficking and subcellular compartmentalization, with implications for cardiac EC coupling. Method HL-1 murine cardiomyocytes were used to study BIN1's partners, identified via affinity purification coupled with mass spectrometry (MS). MS data were acquired using Xcalibur, processed using Proteowizard, and imported into Scaffold. Gene enrichment analysis was performed using ShinyGO, and potential protein interactors were identified using BioGRID. Results Initial proteomic analysis of BIN1 interactors in cardiomyocytes identified several ion channels, including HCN4. Interestingly, Gene Ontology (GO) term analysis revealed that the BIN1 interactome is enriched in proteins involved in the biological processes related to translation, protein localization and transport, and metabolism. Consistently, interrogation of the BioGRID protein-protein interaction database indicated that HCN4 was recently reported as a hit in the BIN1 interactome in a neuroblastoma cell line (McMillan, 2025). Together, these preliminary results suggest that BIN1 and the pacemaker HCN4 channel interact and may influence each other in cardiomyocytes. Conclusion Our findings suggest a novel role for BIN1 as a scaffold protein for the cardiac pacemaker HCN4 channel, potentially regulating its distribution and function, and thereby impacting on cardiac EC coupling.

Introduction Increasing prevalence of ischemic heart disease, particularly myocardial infarction (MI), carries a major medical and socioeconomic burden. Reduced cardiac contractility in these conditions is partly linked to degradation of subcellular structures called transverse tubules (T-tubules). While mechanisms are unclear, our previous work suggests that the membrane scaffolding protein Bridging Integrator 1 (BIN1) is critical for T-tubule growth and maturation. However, its expression is significantly reduced in heart failure patients and animal models, therefore making BIN1 a promising therapeutic target. Objective This study aims to understand how BIN1 can be modulated and to reverse T-tubule impairment and improve post-MI cardiac function. Method HL-1 murine cardiomyocyte cell line and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were used to study BIN1 and its partners in controlling T-tubule growth at the cellular level. BIN1 interactors were identified using affinity purification coupled with mass spectrometry. In our mouse model of MI, transcript and protein levels were assessed by RT-qPCR and Western-blotting. Cardiac remodeling and T-tubule organization were examined by histology, immunohistochemistry, and immunofluorescence followed by confocal microscopy. Results A protein profile involved in tubulogenesis was established using HL-1 cardiomyocytes. Promising BIN1-partners were confirmed by co-localization and immunoprecipitation, and characterized for their role in regulating BIN1-induced T-tubule growth in HL-1 cells and hiPSC-CMs. We then further investigated BIN1 and the promising protein hits to prevent T-tubule degradation in vivo in a MI disease setting. In our mouse model of MI, preliminary results showed that BIN1 and MTM1 were downregulated, while RIN3 was upregulated. Conclusion BIN1 and its partners are promising targets to restore the cardiac T-tubule network after MI.

Purpose Atopic keratoconjunctivitis (AKC) is a chronic, severe ocular surface disease associated with atopic dermatitis, which may impair vision and ultimately lead to blindness. In this study, discovery-based proteomic analysis was performed on tear samples from patients with AKC to elucidate molecular characteristics and identify proteins of interest. Methods All patients underwent thorough ophthalmological examination and were divided into four subgroups: healthy controls (n = 17), atopic dermatitis without ocular surface disease (n = 11), mild (n = 65), and moderate-severe AKC (n = 32). Tear film samples collected with Schirmer’s filtration paper were analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Proteins were considered significantly regulated if they demonstrated a p-value lower than 0.05, following correction for multiple hypothesis testing, and if they exhibited a fold change greater than 2. Results A total of 2503 proteins were identified. Compared with controls, mild AKC and moderate-severe AKC showed 14 and 29 significantly regulated proteins, respectively. Mild vs moderate-severe AKC yielded 21 significantly regulated proteins. Four proteins overlapped in both mild AKC and moderate-severe AKC compared to healthy controls: Short-chain specific acyl-CoA dehydrogenase, serpin B13, non-secretory ribonuclease, and probable E3 ubiquitin-protein ligase HERC4. Regulated proteins were involved in immune-related, metabolic, and epithelial processes. Conclusion This exploratory proteomic study suggests that AKC is associated with changes in immune-related pathways, including mucosal innate immunity, eosinophil migration, and cytokine signaling, as well as metabolic processes, and epithelial differentiation and barrier function.

The eggshell membrane (ESM), resembling the extracellular matrix (ECM), acts as a protective barrier against bacterial invasion and offers various biofunctions due to its porous structure and protein-rich composition, such as ovalbumin, ovotransferrin, collagen, soluble protein, and antimicrobial proteins. However, the structure of ESM primarily comprises disulfide bonds and heterochains, which poses a challenge for protein solubilization/extraction. Therefore, the method of dissolving and extracting bioactive protein components from ESM has significant potential value and importance for exploring the reuse of egg waste and environmental protection. In this study, soluble ESM proteins (SEPs) were extracted from conventional (industrial-fed) and organic (free-grounded) using an acidic 3-mercaptopropionic acid (3-MPA) extraction strategy. FTIR was employed to monitor the chemical changes in the ESM, while LC-MS/MS was used to conduct the proteomic analysis. The biocompatibility and effects of SEP cocktails on ECM synthesis were also investigated. The results indicated that the acidic 3-MPA strategy effectively altered the ESM chemical composition, thereby facilitating SEPs extraction. The SEPs from conventional and organic eggs have different protein profiles but with partial overlapping. SEPs from both sources showed similar desirable biosafety profiles and dose-dependent promotion of osteoblastic (ECM) component synthesis, suggesting that different egg sources may contribute to consistent core biological functions of protein products, they may also introduce different functional priorities.

The protein composition of tear fluid (TF) reflects the severity and progression of many age-related diseases. Here, we evaluated TF proteins from patients with mild Alzheimer’s disease (AD) and cognitively healthy controls (CO) to explore potential new biomarker molecules. The aim of this study was to explore potential new biomarker molecules by examining the expression of TF proteins whose function is related to neuroinflammation. We examined 53 participants (34 COs, mean age 71 years, Mini-Mental State Examination (MMSE) score 28.9 ± 1.4; 19 with AD, Clinical Dementia Rating 0.5–1, mean age 72 years, MMSE 23.8 ± 2.8). All participants underwent neurological status examination, cognitive testing, and ophthalmological examination. TF was collected using Schirmer strips, and TF protein content was evaluated using mass spectrometry-based proteomics and label-free quantification. We report 14 TF proteins that showed altered protein expression in the AD group compared to the CO group. Twelve proteins were significantly upregulated (SERPINA3, FGA, SIAS, ORM1, ANXA3, G6PI/NLK, CH3L2, MSLN, CPPED1, JCHAIN, IGHV5-51, SPARCL1) and two were downregulated (PIP, SCGB2A1) (p ≤ 0.05). Observed altered expression of TF proteins in the AD group may have potential in AD pathology. Since inflammation is one of the earliest signs of neurodegeneration in AD, these proteins are putative new biomarker candidates of early AD.

Background and objectives: Dental implants are commonly used for tooth replacement, with excellent success rates over 10 years. However, exposure to oral cavity bacteria makes them susceptible to biofilm accumulation, which can lead to peri-implant diseases. The salivary pellicle, a protein-rich layer formed on implant surfaces, mediates bacterial adhesion and cell attachment. Effective decontamination is essential for managing bacterial infections, yet no consensus exists on the best chemical agent. Understanding how chemical agents affect the pellicle proteomic profile may guide the selection of optimal treatments. Methods: We investigate the impact of chemical decontamination agents on the salivary pellicle on OsseoSpeed-like titanium dental implant surfaces using a BCA assay and proteomics, and on cell adhesion using human gingival fibroblasts (HGF) and human bone marrow mesenchymal stem cells (hBMSC). We compare the effects of hydrogen peroxide (H2O2), Poloxamer 407 (P407), P407 + H2O2 and sodium hypochlorite + amino acids (NaOCl + AA) using the salivary pellicle and a clean titanium surface as controls. By quantifying and identifying proteins on titanium surfaces after decontamination, this study reveals how chemical agents affect the salivary pellicle. Results: All products reduced the total protein on the surfaces, with the P407 + H2O2 hydrogel demonstrating lower protein variety and superior effectiveness in preventing surface recontamination. Not all proteins were removed during decontamination procedures, and unique proteins were detected in each experimental condition, suggesting protein readsorption depends on surface chemistry. P407 + H2O2 shows the highest enrichment in integrin- and cadherin-binding proteins upon recontamination. P407 and P407 + H2O2 promoted HGFs and hBMSCs attachment. Conversely, NaOCl + AA and H2O2 showed lower HGFs and hBMSCs counts. Conclusion: The P407 + H2O2 hydrogel had the strongest decontamination effect and limited surface recontamination. Each chemical agent produced a distinct proteomic profile. P407 and P407 + H2O2 promoted initial cell adhesion.

OBJECTIVES:In this study, we aimed to explore the protein content of bacterial extracellular vesicles (bEVs) from three strains of Porphyromonas gingivalis, an anaerobic gram-negative bacterium closely associated with periodontitis. Additionally, we aimed to investigate the effects of bEV uptake on human oral fibroblasts, to better understand the role of these vesicles in the pathogenesis of periodontitis. DESIGN:Liquid chromatography-mass spectrometry was performed on bEVs from three strains of P. gingivalis with different virulence: ATCC 33277, A7A1-28, and W83. Three key proteins associated with virulence were validated using dot blot. Proliferation and viability of human oral fibroblasts after incubation with bEVs were assessed at different timepoints and different concentrations of bEVs. RESULTS:A total of 307 proteins were identified in the bEVs from the three strains of P. gingivalis. Among those were several relevant for virulence, for example gingipains, fimbriae, and peptidyl-arginine deiminase (PPAD). When oral fibroblasts were exposed to bEVs from A7A1-28 or W83, proliferation was significantly affected after 12 and 24 h at one bEV concentration. Furthermore, viability was significantly affected by bEVs from W83 at several timepoints and bEV concentrations. bEVs from ATCC 33277 did not induce any significant changes. CONCLUSION:Several proteins associated with virulence were detected in bEVs from all three strains of P. gingivalis, with varying abundance. Uptake of these bEVs can influence human cells, as exemplified by changes in viability and proliferation.

Piscine myocarditis virus (PMCV) causes chronic, necrotizing myocarditis in Atlantic salmon. Originally, PMCV was identified based on its genetic homology and genomic organization, indicating a relationship to viruses of the Ghabrivirales order, specifically the former Totiviridae family, whose members predominantly infect fungi or protozoans and lack an extracellular life cycle stage. However, PMCV was the first virus of this order found to infect a vertebrate host. Since then, other piscine viruses and viruses infecting terrestrial and aquatic arthropods have been described and recently assigned to new virus families within the order. PMCV is now classified in Pistolviridae. All these viruses infecting multicellular hosts encode proteins that are believed to be involved in extracellular transmission. In PMCV, this relates to a protein of size 33.4 kDa (p33) encoded by a unique third open reading frame. To investigate its characteristics and role, we expressed various recombinant variants of p33 in cultured cells. Our results demonstrate that p33 expression induces a cytotoxic phenotype in transfected cells. The full-length protein undergoes processing into smaller peptide variants. Previous in silico analysis predicted an N-terminal chemokine-like domain, and our present results show that this domain is secreted as peptides capable of inducing cytotoxicity when expressed alone. The C-terminal region includes sequence characteristics of a small hydrophobic domain, which appears crucial for the correct processing of the full-length protein into N- and C-terminal peptides and directing the C-terminal peptides to a high membrane concentration. Investigations into p33 function could elucidate how PMCV achieves extracellular transmission, a mechanism that may be conserved among viruses of Pistolviridae. The findings in this study provide evidence that p33 has structural and functional characteristics of a protein adapted to facilitate host cell membrane interaction and cell lysis, potentially enabling extracellular viral release. These insights may provide evolutionary evidence that pistolviruses have acquired the uncommon trait of viral transmission within the order Ghabrivirales, broadening our understanding of virus–host adaptation in vertebrates.

BackgroundTear fluid (TF) is a protein-rich solution that reflects pathophysiological changes in Alzheimer's disease (AD).ObjectiveIn this study, we examined whether TF proteins were differently expressed in persons with mild AD dementia compared to cognitively healthy controls (CO).MethodsWe analyzed data from 53 study participants including 34 CO (mean age, 71 years; Mini-Mental State Examination [MMSE] score, 28.9 ± 1.4), and 19 patients with AD (Clinical Dementia Rating, 0.5-1; mean age, 72 years; MMSE score, 23.8 ± 2.8). All participants underwent cognitive testing, as well as neurological and ophthalmological examinations. TF was collected using Schirmer strips, and TF protein content was evaluated using mass spectrometry-based proteomics and label-free quantification.ResultsWe found that 16 proteins exhibited significantly upregulated expression in the AD group compared to the CO group (p ≤ 0.05). These proteins were NP1L4, BBOX1, CYTC, RNAS4, PCD, RNT2, AL1A3, SYSC, TPIS, CLH1, PGAM1, EIF3L, 5NTC, HNRNPA2B1, PYGL, and ERO1α. No proteins were significantly downregulated in the AD group compared to the CO group.ConclusionsOur results support the hypothesis that TF is a potential source of biomarkers for AD. Part of those proteins with altered expression have previously linked to increased oxidative stress, changed protein synthesis, and disturbed regulation of energy metabolism related to AD or neurodegenerative disease. The present results indicate the value of continued investigation of TF proteins in AD.

OBJECTIVES:This study aimed to investigate the impact of hydrogen peroxide-induced oxidative stress on the protein expression profiles of submandibular and parotid acinar cells using a proteomic approach. We sought to evaluate how oxidative stress might contribute to salivary gland dysfunction and whether the two glands respond differently. DESIGN:Immortalized rat parotid gland (PG) and submandibular gland (SMG) acinar epithelial cell lines were exposed to 50 µM and 150 µM hydrogen peroxide for 24 hr, followed by protein identification and quantification via liquid chromatography-mass spectrometry. Immunofluorescence microscopy and western blot analysis validated selected protein expressions, and cell viability was assessed using trypan blue exclusion assays. RESULTS:Compared to controls, histone H4 expression increased in both cell types after hydrogen peroxide exposure, whereas voltage-dependent anion-selective channel 1, keratin 7, and keratin 8 increased only in parotid gland cells. Conversely, mitochondrial aldehyde dehydrogenase and kidney isoform glutaminase were downregulated in parotid gland cells. Basal expression of mitochondrial aldehyde dehydrogenase and catalase was higher in submandibular gland cells. At higher hydrogen peroxide concentrations, antioxidant proteins expression and cell viability were greater in submandibular gland cells compared to parotid gland cells. CONCLUSIONS:Our results suggest that submandibular gland acinar cells exhibit greater resistance to oxidative stress compared to parotid gland cells, potentially due to distinct antioxidant and metabolic coping strategies. Understanding these gland-specific responses may contribute to future approaches to protect salivary glands from oxidative damage under pathological conditions.

Coagulation factor (F) VII deficiency is the most frequent among the rare, inherited bleeding disorders and is predominantly caused by missense mutations in the F7 gene. The disease phenotype ranges from asymptomatic cases to extremely severe hemorrhagic forms, requiring prophylactic injections with plasma-derived or recombinant FVII concentrates. In response, we have developed an autologous cell-based approach that corrects the disease-causing mutation in patient-derived induced pluripotent stem cells (iPSC) and generates therapeutic, three-dimensional hepatic organoids (HO). We report the CRISPR-mediated correction of homozygous c.718G>C (p.G240R), a missense mutation associated with a severe, life-threatening bleeding phenotype. The HO contain all liver cell types and exhibit key liver functions, including coagulation factor production. After correction, our data indicate that the patient-derived HO secrete consistent amounts of functional FVII protein, resulting in improved thrombin generation times. These results represent a significant milestone toward the establishment of an autologous cell-based therapy for patients with FVII- and other coagulation factor deficiencies.

This work aimed to simplify and improve the process of binding monoclonal antibodies (mAbs) covalently to filter paper for use in dried blood spot sampling, enabling instant capture of protein biomarkers for targeted protein determination. Incorporating the necessary immunocapture sample preparation step in the initial sampling stage saves time and reduces the workload. The biomarker human chorionic gonadotropin (hCG) was used as the model analyte. The antibody-based paper samplers were prepared by functionalizing paper discs (6 mm) through a simple reaction using divinyl sulfone (DVS). After DVS activation, the paper discs were incubated with E27 hCG mAbs, followed by 0.05% tween/phosphate buffer saline to block the surface. After sample application and drying, the discs only needed to be washed before tryptic digestion and finally analysed on a nanoliquid chromatography-tandem mass spectrometry system. The finished DVS-mAbs samplers could selectively capture hCG (100 ng/mL) from human serum, with a recovery of 50%. Sample clean-up reduced the number of identified proteins from 132 to 82 before and after wash, respectively, with a 70% reduction in serum albumin signal while still retaining hCG on the sampler during the washing protocol. An evaluation of the samplers revealed excellent linearity (R2  = 0.9995) for hCG in serum with relative standard deviations below 15%. This work has presented the first ever reported paper samplers immobilized with antibodies utilizing DVS chemistry, showing promise in the future of paper-based sampling.

Crucian carp (Carassius carassius), a freshwater fish, can survive chronic anoxia for several months at low temperatures. Consequently, anoxia-related physiological and biochemical adaptations in this species have been studied for more than half a century. Still, despite for the well-known role of protein phosphorylation in regulating cellular processes, no studies have comprehensively characterized the phosphoproteome in crucian carp. In this study, we report the global phosphoproteome in crucian carp brain and liver during anoxia and reoxygenation. By applying a bottom-up proteomic approach on enriched phosphopeptides we found that the brain phosphoproteome shows surprisingly few changes during anoxia-reoxygenation exposure with only 109 out of 4200 phosphopeptides being differentially changed compared to normoxic controls. By contrast, in the liver 395 out of 1287 phosphopeptides changed. Although most changes occurred in the liver phosphoproteome, the pattern of changes indicated metabolic depression and decreased translation in both brain and liver. We also found changes in phosphoproteins involved in apoptotic regulation and reactive oxygen species handling in both tissues. In the brain, some of the most changed phosphopeptides belonged to proteins involved in central nervous system development and neuronal activity at the synaptic cleft. Changed phosphoproteins specific for liver tissue were related to glucose metabolism, such as glycolytic flux and glycogenolysis. In conclusion, protein phosphorylation in response to anoxia and reoxygenation showed both common and tissue-specific changes related to the functional differences between brain and liver.

Introduction Increasing prevalence of ischemic heart disease and particularly myocardial infarction (MI) carries a high socioeconomic burden, and treatment strategies are limited. Emerging data from our group have indicated that reduced cardiac contractility in this condition is linked to degradation of subcellular structures called t-tubules. While the underlying mechanisms are unclear, our data suggest that the interplay between the scaffolding protein BIN1 and specific lipids called phospho-inositides (PIs) is critically involved. Objective The objective of this study is to establish that BIN1 and PI homeostasis precisely controls cardiac t-tubule growth, maturation, and maintenance. We additionally aim to target these pathways to reverse t-tubule remodeling during MI. Method We are making use of the HL-1 cardiomyocyte cell line, isolated mouse cardiomyocytes, and an in vivo mouse model of MI to thoroughly study the collaborative roles of BIN1 and PIs in controlling cardiac t-tubule growth. Transcript and protein levels of target proteins in heart tissue are assessed by RT-qPCR and Western-blotting. T-tubule organization is studied by immunofluorescence and immunohistochemistry followed by confocal microscopy. Results In a first part, we are working on the establishment of a cardiac “t-tubule interactome” in HL-1 cardiomyocytes, using affinity purification coupled to mass spectrometry to identify key pathways implicated in tubulogenesis and lipid homeostasis. Our initial confirmation by co-localization and Western-blotting, indicates that the BIN1-partners DNM2, MTM1, RIN2, RIN3, and SYNJ2 are the most propitious. We have also started to determine the lipid composition of t-tubules, using probes for membrane polarity and lipidomic.We are further investigating the promising target proteins in a cardiac disease setting. This work is carried out in a well-established mouse model of acute MI followed by 3h–28days of reperfusion. Our encouraging initial results suggest a downregulation of BIN1 and MTM1 as well as an upregulation of RIN3 at the protein level during MI. Conclusion Thus, this work will provide exciting new insight into both the pathophysiology and treatment of MI.

Background New biomarkers that improve diagnosis of Alzheimer's disease (AD) are warranted. Tear fluid (TF) containing variety of proteins that reflect pathophysiological changes of systemic diseases makes TF proteins potential biomarker candidates for AD. Objective We investigated the expression levels of TF proteins in persons with mild AD and cognitively healthy controls (CO) to find out if altered proteins may link to the AD pathophysiology. Methods We analyzed the data of the 53 study participants (34 COs, mean age 71 and Mini-Mental State Examination (MMSE) 28.9 +/- 1.4 and 19 persons with AD, CDR 0.5-1, mean age 71 and MMSE 23.8 +/- 2.8). All went through neurological status examination, cognitive tests, and ophthalmological examination. TF was collected using Schirmer strips. The TF protein content was evaluated via mass spectrometry-based proteomics and label-free quantification. Results Eleven proteins having a role either in protein repair and clearance system, or regulation of cytoskeleton, showed altered expression in AD group compared to CO group. Seven of them were significantly (p <= 0.05) upregulated (Sti1, Twf1, Myl6, Otub1, Pls1 and Caza1) or, downregulated (HSP90) in AD group. Conclusions Altered expression of all these up- or downregulated proteins may be linked to AD pathophysiology. Thus, our results are encouraging for searching new biomarker candidates for AD. TF is potential biomarker candidate, because TF seems to reflect altered protein levels already in mild AD dementia.

Neovascular age-related macular degeneration (AMD) is a major cause of irreversible blindness in elderly populations in developed countries. AMD’s etiopathology is multifactorial, with strong environmental and genetic components, but the exact molecular pathomechanisms underlying the disease are still unknown. In this study, we analyzed blood serum collected from 74 neovascular AMD patients and 58 healthy controls to identify proteins that may serve as potential biomarkers and expand our knowledge about the etiopathogenesis of the disease. The study revealed 17 differentially expressed proteins—11 up-regulated and 6 down-regulated—in neovascular AMD, which are involved in the biological processes previously linked with the disease—oxidative stress and persistent inflammation, impaired cellular transport, lipid metabolism and blood coagulation. In conclusion, the differences in the expressions of the proteins identified in this study may contribute to our understanding of the mechanisms underlying AMD and possibly serve in future as promising biomarkers.