Role of alpha-1 antitrypsin in human health and disease

Alpha-1 antitrypsin deficiency-associated liver disease: From understudied disorder to the poster child of genetic medicine

Alpha-1 antitrypsin deficiency (AATD) constitutes an inborn disorder arising due to mutations in alpha-1 antitrypsin (AAT), a secreted protease inhibitor produced primarily in hepatocytes. It leads to diminished serum AAT levels, and this loss-of-function predisposes to chronic obstructive pulmonary disease and lung emphysema. The characteristic Pi*Z mutation results in hepatic Z-AAT accumulation. In its homozygous form (Pi*ZZ genotype), it is responsible for the majority of severe AATD cases and can cause both pediatric and adult liver disease, while the heterozygous form (Pi*MZ) is considered a disease modifier that becomes apparent primarily in the presence of other comorbidities or risk factors. In the current review, we collate conditions associated with AATD, introduce typical AAT variants, and discuss our understanding of disease pathogenesis. We present both cross-sectional and longitudinal data informing about the natural disease history and noninvasive tools that can be used for disease stratification as well as a basis for disease monitoring. Given that AATD-associated liver disease is highly heterogeneous, we discuss the risk factors affecting disease progression. While the loss-of-function lung disease is treated by weekly intravenous administration of purified AAT, recombinant modified AAT and oral protease inhibitors are currently in clinical trials. Among the liver candidates, small interfering RNA fazirsiran efficiently suppresses AAT production and is currently in phase 3 clinical trial, while several other genetic approaches, such as RNA editing, are at earlier stages. In summary, AATD represents a systemic disorder increasingly seen in the hepatologic routine and requiring thorough interdisciplinary care, since the currently ongoing clinical trials often address only one of the organs it affects.

Alpha-1 Antitrypsin Deficiency Screening Using Serum Protein Electrophoresis

Background: Alpha-1 antitrypsin is encoded by the polymorphic SERPINA1 gene, with pathogenic variants causing alpha-1 antitrypsin deficiency. While being underrecognized, alpha-1 antitrypsin deficiency can be screened through serum protein electrophoresis (SPE) to detect mutations. This study aimed to evaluate the effectiveness of an SPE-based screening protocol for identifying SERPINA1 mutations and diagnosing alpha-1 antitrypsin deficiency. Methods: This study involved analyzing all SPE tests over one year at the Hospital Clínico Universitario "Lozano Blesa" (Zaragoza, Spain). Alpha-1 antitrypsin concentration was measured in samples with <3% alpha-1 globulin band, selecting those with <100 mg/dL as potential study participants. Participants provided blood samples for the genetic analysis of the SERPINA1 gene. Results: Out of 12,460 SPE tests analyzed, 175 had alpha-1 globulin bands <3%, and 70 cases had alpha-1 antitrypsin concentrations <100 mg/dL. Of these cases, 39 subjects participated in the study. The mean alpha-1 antitrypsin concentration was 78.8 mg/dL. Genetic analysis showed 87.2% had SERPINA1 mutations, with common genotypes being PI*MS, PI*MZ, and PI*SZ. Conclusions: This study confirms the efficacy of SPE as a potential screening strategy for detecting mutations in the SERPINA1 gene. It can facilitate opportunistic diagnosis of alpha-1 antitrypsin deficiency, promoting early detection and treatment.

Clinical Study Support by Long-Term Stability Studies of Alpha1-Proteinase Inhibitor and Urea in Relevant Biological Matrices

Background/Objectives: According to recent guidelines, including the guideline on bioanalytical method validation issued by the European Medicine Agency, the stability of clinical analytes should be known. We summarize human α1-proteinase inhibitor (A1PI) and urea stability data in relevant matrices, as these analytes are usually measured in clinical A1PI studies. Methods: Stability samples with appropriate A1PI concentrations were prepared in a citrated human reference plasma pool and a matrix mimicking bronchoalveolar lavage (BAL) solution. These samples were kept at -20 °C and -60 °C for up to 24 months. A1PI protein was measured with a nephelometric method and an enzyme-linked immunosorbent assay using paired commercially available polyclonal antibodies. A1PI elastase inhibitory activity was determined with an elastase complex formation immunosorbent assay that combines A1PI complex formation with a solid phase-immobilized elastase and immunological detection of the formed A1PI-elastase complex and urea in samples kept at -20 °C only with an enzymatic assay. Results: Overall, the stability criterion (100 ± 20%) was met for the analytes A1PI protein and A1PI activity at both temperatures during storage of BAL-mimicking and plasma samples for 15 and 24 months, respectively; urea was stable in both matrices at -20 °C for 18 months. Plasma samples showed smaller drops in concentration over storage time than BAL-mimicking samples. As expected, the reduction of A1PI elastase inhibitory activity was more pronounced than that of A1PI protein. Interestingly, the analyte concentration did not significantly influence the results in either of the sample matrices. Conclusions: The data confirmed the appropriate stability of the three analytes in the matrices of citrated plasma and BAL-mimicking samples for at least up to 15 months.

Alpha-1 antitrypsin deficiency and primary liver cancers

Primary liver cancers (PLCs) remain a major challenge to global health and an escalating threat to human life, with a growing incidence worldwide. PLCs are composed of hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), and mixed HCC-CCA, accounting for 85 %, 10 %, and 5 % of cases, respectively. Among the numerous identified risk factors associated with liver cancers, Alpha 1-AntiTrypsin Deficiency (AATD) genetic disease emerges as an intriguing one. AATD-related liver disease may lead to chronic hepatitis, cirrhosis, and PLCs in adulthood. Although our knowledge about the natural history of AATD-liver disease has improved recently, liver cancers associated with AATD remain poorly understood and explored, while this specific population is at a 20 to 50 times higher risk of developing PLC. Thus, we review here current knowledge about AATD-associated PLCs, describing the impact of AATD genotypes on their occurrence. We also discuss emerging hypotheses regarding the AATD PiZZ genotype-related hepatic carcinogenesis process. Finally, we perform an updated analysis of the United Kingdom Biobank database that highlights and confirms AATD PiZZ genotype as an important HCC risk factor.

α‑1 Antitrypsin is a potential target of inflammation and immunomodulation (Review)

α‑1 Antitrypsin (AAT) is an acute phase protein encoded by the serine protease inhibitor family A member 1 gene. This multifunctional protein serves several roles, including anti‑inflammatory, antibacterial, antiapoptotic and immune regulatory functions. The primary role of AAT is to protect tissues and organs from protease‑induced damage due to its function as a serine protease inhibitor. AAT is associated with the development of lung inflammation, liver inflammation and immune‑mediated inflammatory diseases, which are influenced by environmental and genetic factors. For instance, AAT acts as an anti‑inflammatory protein to prevent and reverse type I diabetes. The present study briefly reviewed the molecular properties and mechanisms of AAT, as well as advances in the study of lung, liver and inflammatory diseases associated with AAT. The potential of AAT as a diagnostic and therapeutic target for inflammatory and immune‑mediated inflammatory diseases was reviewed. In addition, the damaging and protective effects of AAT, and its effects on organ function were discussed.

Vascular Pathology in Alpha 1 Antitrypsin Deficient Chronic Obstructive Pulmonary Disease and Emphysema Patients: Case Reports

Alpha 1 Antitrypsin Deficiency (AATD) is a genetic condition that results from mutations in the SERPINA1 gene, which can lead to deficient or dysfunctional Alpha 1 Antitrypsin (AAT) protein production. AATD is linked to chronic obstructive pulmonary disease (COPD) and emphysema. In addition to pulmonary manifestations, AATD has also been associated with vascular pathology due to excessive protease activity, tissue degradation, and vessel stiffening. Early AATD diagnosis is crucial to prevent progressive lung damage and associated pathologies. Here, we present case reports of two patients with AATD from the Temple University Hospital Outpatient Clinic, who exhibited aneurysms of the aorta and splenic artery. AATD should be considered a genetic risk factor for aneurysms and vascular diseases, necessitating cardiovascular monitoring in affected individuals. This report emphasizes both the need for heightened awareness of AATD as a potential etiology of unexplained vascular aneurysms, as well as the need for screening for vascular pathology in patients with AATD-associated COPD and emphysema to facilitate early intervention and improve patient outcomes.

Advancing the understanding and treatment of lung pathologies associated with alpha 1 antitrypsin deficiency

Alpha 1 antitrypsin deficiency (AATD) is a genetic disorder that alters the functionality and/or serum levels of alpha 1 antitrypsin (AAT). Dysfunctional forms of AAT, or low levels of serum AAT, predispose affected individuals to pulmonary complications. When AATD-associated lung disease develops, the most common pulmonary pathology is emphysema. The development of emphysema and decline in lung function varies by AATD genotype and is accelerated by risk factors, such as smoking. To improve the understanding and treatment of AATD, emerging knowledge and unresolved questions need to be discussed. Here we focus on developments in the areas of disease pathogenesis, biomarkers, and clinical endpoints for trials in AATD, as well as barriers to treatment. The clinical impact of AATD on lung function is highly variable and highlights the complexity of AATD pathogenesis, in which multiple underlying processes are involved. Reduced levels of functional AAT disrupt the protease-antiprotease homeostasis, leading to a loss of neutrophil elastase inhibition and the breakdown of elastin within the lung interstitium. Inflammatory processes also play a critical role in the development of AATD-associated lung disease, which is not yet fully understood. Biomarkers associated with the disease and its complications may have an important role in helping to address AATD underdiagnosis and evaluating response to treatment. To improve access to treatment, the problem of underdiagnosis needs to be addressed and the provision of therapeutic options needs to become uniform. Patients should also be empowered to play a key role in the self-management of the disease. Advancing our understanding of the disease will ultimately improve the life expectancy and quality of life for patients affected by AATD.

Serum α1-AT Levels and SERPINA1 Molecular Analysis in Breast Cancer: An Experimental and Computational Study

BACKGROUND/OBJECTIVES

Breast cancer (BC) is a heterogeneous disease with multifactorial origins, including environmental, genetic, and immunological factors. Inflammatory cytokines, such as alpha 1 antitrypsin (α1-AT), are increased in BC and affect physiological and pathological conditions. This study aimed to evaluate the serum levels of α1-AT and perform a computational analysis of SERPINA1 in BC, as well as their association with molecular subtypes and clinical features.

METHODS

For the experimental analysis, we evaluated 255 women with BC and 53 healthy women (HW) in a cross-sectional study. Molecular subtypes were identified by immunohistochemistry and TNM was used for clinical staging. Soluble levels of α1-AT were quantified by ELISA. Computational analysis of SERPINA1 expression was performed using GEPIA and cBioPortal.

RESULTS

α1-AT was increased in BC women versus HW (75.8 ng/mL vs. 532.2 ng/mL). Luminal A had higher concentration (547.5 ng/mL) than Triple Negative (TN) (484.1 ng/mL), but the levels were not associated with clinical stage. The computational analysis showed that SERPINA1 is overexpressed in BC with differential expression among subtypes; its overexpression is associated with a better prognosis, longer disease-free survival, and overall survival.

CONCLUSIONS

α1-AT levels are increased in women with BC women compared to HW. The Luminal A subtype shows higher soluble protein levels than the TN one. Furthermore, SERPINA1 mRNA overexpression in BC is linked to a protective effect.

Genome-Wide Association Analysis of Rapid Decline in Lung Function: Analysis From the Korean Genome and Epidemiology Study

BACKGROUND

A rapid decline in forced expiratory volume in 1 second (FEV1) is considered an important phenotype of the development of chronic obstructive pulmonary disease (COPD). However, the associations between specific genetic variants (single-nucleotide polymorphisms; SNPs) and this phenotype remain uncertain.

METHODS

We enrolled 6,516 individuals from the Korean Genome and Epidemiology Study (KoGES). A rapid decline in FEV1 was defined as an annual decrease of FEV1 ≥ 60 mL/year. A multivariable logistic regression model was used to assess the associations between SNP variants and the rapid decline in FEV1. Considering the significant impact of smoking on lung function, a subgroup analysis based on smoking history was also conducted.

RESULTS

A genome-wide association analysis of the rapid decline in FEV1 identified 15 association signals (P < 5.0 × 10-8). Among the 15 nucleotide variants, rs9833533 and rs1496255 have been previously reported to be associated with lung function development. In the subgroup analysis, rs16951883 (adjusted odds ratio [aOR], 3.24; P = 5.87 × 10-8) was the most significant SNP associated with rapid decline in FEV1 among never smokers, followed by rs41476549, rs16840064, and rs1350110. Conversely, among ever smokers, rs10959478 (aOR, 4.74; P = 8.27 × 10-7) showed the highest significance, followed by rs6805861, rs9833533, and rs16906215.

CONCLUSION

We identified 15 nucleotide variants linked to a rapid decline in FEV1, including two SNPs previously reported to be associated with lung function development. Additional SNPs, which were associated with COPD, may be found using novel phenotypes.

Haplotype-Aware Detection of SERPINA1 Variants by Nanopore Sequencing

α-1 Antitrypsin (AAT) is an acute-phase reactant with immunomodulatory properties that mainly inhibits neutrophil elastase. Low serum levels cause AAT deficiency (AATD), an underdiagnosed condition that predisposes to pulmonary and hepatic diseases. The SERPINA1 gene, which encodes AAT, contains >500 variants. PI∗Z and PI∗S alleles are the most diagnosed causes of AATD, but the role of the SERPINA1 haplotypes in AAT function remains unknown. SERPINA1 gene was PCR amplified from 94 patients with asthma, using primers with tails for indexing. Sequencing libraries were loaded into a MinION-Mk1C, and MinKNOW was used for basecalling and demultiplexing. Nanofilt and Minimap2 were used for filtering and mapping/alignment. Variant calling/phasing were performed with PEPPER-Margin-DeepVariant. SERPINA1 gene was 100% covered for all samples, with a minimum sequencing depth of 500×. A total of 75 single-nucleotide variants (SNVs) and 4 insertions/deletions were detected, with 45 and 2 of them highly polymorphic (minor allele frequency >0.1), respectively. Nine of the SNVs showed differences in allele frequencies when compared with the overall Spanish population. More than 90% of heterozygous SNVs were phased, yielding 91 and 58 different haplotypes for each SERPINA1 amplified region. Haplotype-based linkage disequilibrium analysis suggests that a recombination hotspot could generate variation in the SERPINA1 gene. The proposed workflow enables haplotype-aware genotyping of the SERPINA1 gene by nanopore sequencing, which will allow the development of novel AATD diagnostic strategies.

Proteomic Evidence for Amyloidogenic Cross-Seeding in Fibrinaloid Microclots

In classical amyloidoses, amyloid fibres form through the nucleation and accretion of protein monomers, with protofibrils and fibrils exhibiting a cross-β motif of parallel or antiparallel β-sheets oriented perpendicular to the fibre direction. These protofibrils and fibrils can intertwine to form mature amyloid fibres. Similar phenomena can occur in blood from individuals with circulating inflammatory molecules (and also some originating from viruses and bacteria). Such pathological clotting can result in an anomalous amyloid form termed fibrinaloid microclots. Previous proteomic analyses of these microclots have shown the presence of non-fibrin(ogen) proteins, suggesting a more complex mechanism than simple entrapment. We thus provide evidence against such a simple entrapment model, noting that clot pores are too large and centrifugation would have removed weakly bound proteins. Instead, we explore whether co-aggregation into amyloid fibres may involve axial (multiple proteins within the same fibril), lateral (single-protein fibrils contributing to a fibre), or both types of integration. Our analysis of proteomic data from fibrinaloid microclots in different diseases shows no significant quantitative overlap with the normal plasma proteome and no correlation between plasma protein abundance and their presence in fibrinaloid microclots. Notably, abundant plasma proteins like α-2-macroglobulin, fibronectin, and transthyretin are absent from microclots, while less abundant proteins such as adiponectin, periostin, and von Willebrand factor are well represented. Using bioinformatic tools, including AmyloGram and AnuPP, we found that proteins entrapped in fibrinaloid microclots exhibit high amyloidogenic tendencies, suggesting their integration as cross-β elements into amyloid structures. This integration likely contributes to the microclots' resistance to proteolysis. Our findings underscore the role of cross-seeding in fibrinaloid microclot formation and highlight the need for further investigation into their structural properties and implications in thrombotic and amyloid diseases. These insights provide a foundation for developing novel diagnostic and therapeutic strategies targeting amyloidogenic cross-seeding in blood clotting disorders.

Immortalized mesenchymal stromal cells overexpressing alpha-1 antitrypsin protect acinar cells from apoptotic and ferroptotic cell death

Chronic pancreatitis (CP) is a progressive inflammatory disorder that impairs endocrine and exocrine function. Our previous work showed that mesenchymal stem/stromal cells (MSCs) and MSCs overexpressing alpha-1 antitrypsin (AAT-MSCs) could be therapeutic tools for CP. However, primary MSCs are predisposed to undergo senescence during culture expansion, which limits their therapeutic applications. We generated and characterized immortalized human MSCs (iMSCs) and AAT-MSCs (iAAT-MSCs) and tested their protective effect on 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced acinar cell death in an in vitro cell culture system. Primary MSCs were immortalized by transduction with simian virus 40 large T antigen (SV40LT), and the resulting iMSC and iAAT-MSC lines were analysed for proliferation, senescence, phenotype and multi-differentiation potential. Subsequently, apoptosis and ferroptosis pathways were investigated by assessing changes before and after TNBS treatment. Coculture of iMSCs and iAAT-MSCs with acinar cell lines inhibited early cell death induced by TNBS, reduced ER stress and reversed TNBS-induced protein reduction at tight junctions. Additionally, iMSCs and iAAT-MSCs exerted such protection by regulating mitochondrial respiration, ATP content and ROS production in TNBS-induced acinar cells. Furthermore, iMSCs and iAAT-MSCs ameliorated TNBS-induced ferroptosis by modulating iron generation and ROS production and regulating the ferritin heavy chain 1 (FTH1)/protein disulfide isomerase (PDI)/glutathione peroxide 4 (GPX4) signalling pathways in acinar cells. These findings identify ferroptosis as an unrecognized mechanism that leads to TNBS-induced cell death and offer mechanistic insights relevant to using stem cell therapy to treat acinar cell death associated with CP.

Assessment and monitoring of lung disease in patients with severe alpha 1 antitrypsin deficiency: a european delphi consensus of the EARCO group

BACKGROUND

Currently, there is conflicting information and guidance on the effective management of Alpha 1 Antitrypsin Deficiency (AATD). Establishing a consensus of assessment and disease management specific to AATD is important for achieving a standardized treatment pathway and for improving patient outcomes. Here, we aim to utilize the Delphi method to establish a European consensus for the assessment and management of patients with severe AATD.

METHODS

Two rounds of a Delphi survey were completed online by members of the European Alpha-1 Research Collaboration (EARCO). Respondents were asked to indicate their agreement with proposed statements for patients with no respiratory symptoms, stable respiratory disease, and worsening respiratory disease using a Likert scale of 1-7. Levels of agreement between respondents were calculated using a weighted average.

RESULTS

Round 1 of the Delphi survey was sent to 103 members of EARCO and 38/103 (36.9%) pulmonologists from across 15 countries completed all 109 questions. Round 2 was sent to all who completed Round 1 and 36/38 (94.7%) completed all 79 questions. Responses regarding spirometry, body plethysmography, high-resolution computed tomography, and the initiation of augmentation therapy showed little variability among physicians, but there was discordance among other aspects, such as the use of low-dose computed tomography in both a research setting and routine clinical care.

CONCLUSIONS

These results provide expert opinions for the assessment and monitoring of patients with severe AATD, which could be used to provide updated recommendations and standardized treatment pathways for patients across Europe.

Proteomic landscape of epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is a deadly disease with limited diagnostic biomarkers and therapeutic targets. Here we conduct a comprehensive proteomic profiling of ovarian tissue and plasma samples from 813 patients with different histotypes and therapeutic regimens, covering the expression of 10,715 proteins. We identify eight proteins associated with tumor malignancy in the tissue specimens, which are further validated as potential circulating biomarkers in plasma. Targeted proteomics assays are developed for 12 tissue proteins and 7 blood proteins, and machine learning models are constructed to predict one-year recurrence, which are validated in an independent cohort. These findings contribute to the understanding of EOC pathogenesis and provide potential biomarkers for early detection and monitoring of the disease. Additionally, by integrating mutation analysis with proteomic data, we identify multiple proteins related to DNA damage in recurrent resistant tumors, shedding light on the molecular mechanisms underlying treatment resistance. This study provides a multi-histotype proteomic landscape of EOC, advancing our knowledge for improved diagnosis and treatment strategies.

Pulmonary manifestations of alpha 1 antitrypsin deficiency

Alpha 1 antitrypsin deficiency is a widely under recognized autosomal codominant condition caused by genetic mutations in the SERPINA 1 gene, which encodes for alpha 1 antitrypsin (AAT), a serine protease inhibitor. The SERPINA 1 gene contains 120 variants and mutations in the gene may decrease AAT protein levels or result in dysfunctional proteins. This deficiency leads to unopposed protease activity in tissues, thereby promoting pulmonary and hepatic disease. The most common genotype associated with pulmonary disease is the ZZ genotype, and the most frequent pulmonary manifestation is emphysema. Although its pathophysiology may differ from cigarette smoking related chronic obstructive pulmonary disease, smoking itself can hasten lung decline in alpha 1 antitrypsin deficiency (AATD). The diagnosis of AATD is made through AAT protein testing along with genotyping. AATD patients with obstructive airflow limitation may qualify for intravenous augmentation with AAT. However, there is ongoing research to allow for earlier detection and treatment. This review describes in general terms the genetic mechanisms of AATD; its pathogenesis and the impact of cigarette smoke; and its clinical manifestations, diagnosis, treatment, and prognosis. We hope to stimulate research in the field, but mostly we wish to enhance awareness to promote early diagnosis and treatment in those eligible for intervention.

Heterozygous SERPINA1 Defects and Their Impact on Clinical Manifestations of Patients with Predominantly Antibody Deficiencies

Patients with predominantly antibody deficiencies (PADs) display hypogammaglobulinemia with a high prevalence of infections, along with autoimmune manifestations, benign and malignant lymphoproliferation and granulomatous disease. It is noteworthy that PAD patients, even those with defects in the same causative genes, display a variable clinical phenotype, suggesting that additional genetic polymorphisms, located in either immune-related or non-immune-related genes, may affect their clinical and laboratory phenotype. In this context, we analyzed 80 PAD patients, including 70 with common variable immunodeficiency (CVID) for SERPINA1 defects, in order to investigate the possible contribution to PAD clinical phenotype. Ten CVID patients carried heterozygous pathogenic SERPINA1 defects with normal alpha-1 antitrypsin levels. Interestingly, the presence of the Z allele (rs28929474), which was found in three patients, was significantly associated with liver disease; hepatic complications were also observed in patients carrying the p.Leu23Gln (rs1379209512) and the p.Phe76del (rs775982338) alleles. Conversely, no correlation of SERPINA1 defective variants with respiratory complications was observed, although patients with pathogenic variants exhibit a reduced probability of developing autoimmune diseases. Therefore, we recommend SERPINA1 genetic analysis in PAD in order to identify patients with a higher risk for liver disease.

Genetic Epidemiology of Alpha-1 Antitrypsin Deficiency in Macaronesia

INTRODUCTION

The prevalence of alpha-1 antitrypsin deficiency (AATD) in Macaronesia (i.e., Azores, Madeira, Canary Islands, and Cape Verde archipelagos) is poorly known. Our goal was to update it by selecting the most reliable available articles.

METHOD

Literature search using MEDLINE, Embase (via Ovid), and Google Scholar, until December 2023, for studies on prevalence of AATD in the general population and in screenings, published in peer-reviewed journals.

RESULTS

Three studies carried out in the general population of Madeira, La Palma, and Cape Verde, and three screenings carried out in La Palma (2) and Gran Canaria (1) were selected. The frequencies of PI*S in the general population showed an ascending gradient, from South to North, with values (per thousand) of 35 in Cape Verde, 82 in La Palma, and 180 in Madeira. The PI*Z frequencies showed this same gradient, with values of 2 × 1,000 in Cape Verde, 21 in La Palma, and 25 in Madeira. Screenings detected high percentages of defective alleles, including several rare and null alleles, some unique to these islands.

CONCLUSION

The frequencies of PI*S and PI*Z in Madeira are comparable to the highest in the world. Those of the Canary Islands are similar to those of the peninsular population of Spain, and contrast with the low rates of Cape Verde. Screenings detected high numbers of deficient alleles. These results support the systematic investigation of AATD in clinically suspected patients and in relatives of index cases, to reduce underdiagnosis and apply early preventive and therapeutic measures in those affected.

Glycoengineered recombinant alpha1-antitrypsin results in comparable in vitro and in vivo activities to human plasma-derived protein

Alpha-1-antitrypsin (A1AT) is a multifunctional, clinically important, high value therapeutic glycoprotein that can be used for the treatment of many diseases such as alpha-1-antitrypsin deficiency, diabetes, graft-versus-host-disease, cystic fibrosis and various viral infections. Currently, the only FDA-approved treatment for A1AT disorders is intravenous augmentation therapy with human plasma-derived A1AT. In addition to its limited supply, this approach poses a risk of infection transmission, since it uses therapeutic A1AT harvested from donors. To address these issues, we sought to generate recombinant human A1AT (rhA1AT) that is chemically and biologically indistinguishable from its plasma-derived counterpart using glycoengineered Chinese Hamster Ovary (geCHO-L) cells. By deleting nine key genes that are part of the CHO glycosylation machinery and expressing the human ST6GAL1 and A1AT genes, we obtained stable, high producing geCHO-L lines that produced rhA1AT having an identical glycoprofile to plasma-derived A1AT (pdA1AT). Additionally, the rhA1AT demonstrated in vitro activity and in vivo half-life comparable to commercial pdA1AT. Thus, we anticipate that this platform will help produce human-like recombinant plasma proteins, thereby providing a more sustainable and reliable source of therapeutics that are cost-effective and better-controlled with regard to purity, clinical safety and quality.

The association of tumor-expressed REG4, SPINK4 and alpha-1 antitrypsin with cancer-associated thrombosis in colorectal cancer

Novel biomarkers are needed to improve current imperfect risk prediction models for cancer-associated thrombosis (CAT). We recently identified an RNA-sequencing profile that associates with CAT in colorectal cancer (CRC) patients, with REG4, SPINK4, and SERPINA1 as the top-3 upregulated genes at mRNA level. In the current study, we investigated whether protein expression of REG4, SPINK4 and alpha-1 antitrypsin (A1AT, encoded by SERPINA1) in the tumor associated with CAT in an independent cohort of CRC patients. From 418 patients with resected CRC, 18 patients who developed CAT were age, sex, and tumor stage-matched to 18 CRC patients without CAT. Protein expression was detected by immunohistochemical staining and scored blindly by assessing the H-score (percentage positive cells*scoring intensity). The association with CAT was assessed by means of logistic regression, using patients with an H-score below 33 as reference group. The odds ratios (ORs) for developing CAT for patients with A1AThigh, REG4high, SPINK4high tumors were 3.5 (95%CI 0.8-14.5), 2.0 (95%CI 0.5-7.6) and 2.0 (95%CI 0.5-7.4) when compared to A1ATlow, REG4low, SPINK4low, respectively. The OR was increased to 24.0 (95%CI 1.1-505.1) when two proteins were combined (A1AThigh/REG4high). This nested case-control study shows that combined protein expression of A1AT and REG4 associate with CAT in patients with colorectal cancer. Therefore, REG4/A1AT are potential biomarkers to improve the identification of patients with CRC who may benefit from thromboprophylaxis.

[Effects of α1-antitrypsin on motor function in mice with immature brain white matter injury]

OBJECTIVES

To investigate the effects of α1-antitrypsin (AAT) on motor function in adult mice with immature brain white matter injury.

METHODS

Five-day-old C57BL/6J mice were randomly assigned to the sham surgery group (n=27), hypoxia-ischemia (HI) + saline group (n=27), and HI+AAT group (n=27). The HI white matter injury mouse model was established using HI methods. The HI+AAT group received intraperitoneal injections of AAT (50 mg/kg) 24 hours before HI, immediately after HI, and 72 hours after HI; the HI+saline group received intraperitoneal injections of the same volume of saline at the corresponding time points. Brain T2-weighted magnetic resonance imaging scans were performed at 7 and 55 days after modeling. At 2 months of age, adult mice were evaluated for static, dynamic, and coordination parameters using the Catwalk gait analysis system.

RESULTS

Compared to the sham surgery group, mice with HI injury showed high signal intensity on brain T2-weighted magnetic resonance imaging at 7 days after modeling, indicating significant white matter injury. The white matter injury persisted at 55 days after modeling. In comparison to the sham surgery group, the HI+saline group exhibited decreased paw print area, maximum contact area, average pressure, maximum pressure, paw print width, average velocity, body velocity, stride length, swing speed, percentage of gait pattern AA, and percentage of inter-limb coordination (left hind paw → left front paw) (P<0.05). The HI+saline group showed increased inter-paw distance, percentage of gait pattern AB, and percentage of phase lag (left front paw → left hind paw) compared to the sham surgery group (P<0.05). In comparison to the HI+saline group, the HI+AAT group showed increased average velocity, body velocity, stride length, and swing speed (right front paw) (P<0.05).

CONCLUSIONS

The mice with immature brain white matter injury may exhibit significant motor dysfunction in adulthood, while the use of AAT can improve some aspects of their motor function.

The presence of enteropathy in HIV infected children on antiretroviral therapy in Malawi

BACKGROUND

Undernutrition and malnutrition in children in low- and middle-income countries contribute to high mortality rates. Stunting, a prevalent form of malnutrition, is associated with educational and productivity losses. Environmental enteric dysfunction (EED) and human immunodeficiency virus (HIV) infection worsen these conditions. This study seeks to investigate the presence of enteropathy using EED fecal biomarkers in HIV-infected children who are stable on antiretroviral therapy (ART) across various nutritional statuses. By understanding the interplay between EED, HIV, and nutritional status, this study aims to provide insights that can inform targeted interventions to optimize nutritional outcomes in HIV infected children.

METHODS/PRINCIPAL FINDINGS

This study evaluated the levels of alpha-1-antitrypsin, calprotectin and myeloperoxidase in frozen fecal samples from 61 HIV infected (mean age 9.16 ±3.08 years) and 31 HIV uninfected (6.65 ±3.41 years) children in Malawi. Anthropometric measurements and clinical data were collected. The height-for-age z-score (-1.66 vs -1.27, p = 0.040) and BMI-for-age z-score (-0.36 vs 0.01, p = 0.037) were lower in HIV infected children. Enzyme-linked immunosorbent assays were used to measure biomarker concentrations. Statistical tests were applied to compare biomarker levels based on HIV status and anthropometric parameters. Myeloperoxidase, alpha-1-antitrypsin, and calprotectin concentrations did not differ between HIV infected and HIV uninfected children of different age groups. In HIV infected children from 5-15 years, there is no difference in biomarker concentration between the stunted and non-stunted groups.

CONCLUSION/SIGNIFICANCE

Our study found a higher prevalence of stunting in HIV infected children compared to uninfected children, but no significant differences in biomarker concentrations. This suggests no causal relationship between enteropathy and stunting in HIV infected children. These results contribute to the understanding of growth impairment in HIV infected children and emphasize the need for further research, particularly a longitudinal, biopsy-controlled study.

Monitoring the Secretion and Activity of Alpha-1 Antitrypsin in Various Mammalian Cell Types

Overexpression of recombinant protein in mammalian cells is widely used for producing biologics, as protein maturation and post-translational modifications are similar to human cells. Some therapeutics, such as mRNA vaccines, target nonnative cells that may contain inefficient secretory machinery. For example, gene replacement therapies for alpha-1 antitrypsin (AAT), a glycoprotein normally produced in hepatocytes, are often targeted to muscle cells due to ease of delivery. In this chapter, we define methods for expressing AAT in representative cell types such as Huh-7; hepatocytes; Chinese hamster ovarian cells (CHO), a common host to produce biologics; and C2C12, a muscle progenitor cell line. Methods for metabolically labeling AAT to monitor secretion in these cell lines are described along with the use of proteostasis activators to increase the amount of AAT secreted in both C2C12 myoblasts and differentiated myotubes. Assays to assess the activity and glycan composition of overexpressed AAT are also presented. The usage of the proteostasis activator SAHA provided a 40% improvement in expression of active AAT in muscle-like cells and may be an advantageous adjuvant for recombinant production of proteins delivered by mRNA vaccines.

Association between salivary proteases and protease inhibitors linked with viral infections and oral inflammatory diseases

INTRODUCTION

Despite the role of transmembrane protease, serine 2 (TMPRSS2) in facilitating the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the primary cause of the global COVID-19 pandemic, the interaction of extracellular and intracellular proteases in this process remains poorly elucidated. Thus, we monitored the salivary expression concentration (SEC) of TMPRSS2 and its inhibitor, alpha-1 antitrypsin (A1AT), and investigated whether oral inflammatory diseases affected the SEC of both proteins.

MATERIALS AND METHODS

We collected saliva samples before and after surgical treatment of inflammatory cystic diseases (radicular and inflammatory dentigerous cysts) in 25 patients. The SEC of TMPRSS2 and A1AT was measured using enzyme-linked immunosorbent assay. SEC in multiple patient status groups and subgroups of each status were investigated. Finally, the correlation between TMPRSS2 and A1AT SEC was analyzed.

RESULTS

The TMPRSS2 and A1AT SEC did not significantly change pre- or post-treatment. The TMPRSS2 SEC was significantly higher before and after treatment in patients aged >50 years, patients with radicular cysts, and patients with the basic disease. A1AT SEC was significantly decreased after treatment in the acute inflammation, large-sized, and patients without basic disease groups. No significant correlation was observed between the SEC of either protein before and after treatment.

DISCUSSION

Individual-specific SEC for TMPRSS2 may be influenced by age, lesion type, and basic disease; however, oral inflammatory diseases may not have a direct effect. Moreover, the extent of oral inflammatory diseases and the presence of basic diseases may be associated with A1AT SEC. Furthermore, the SEC between the two proteins may be independent.

An Alpha-1 Antitrypsin Deficiency Screening Study in Patients with Chronic Obstructive Pulmonary Disease, Bronchiectasis, or Asthma in Turkey

Purpose

Alpha-1 antitrypsin deficiency (AATD) is a rare hereditary condition characterized by decreased serum alpha-1 antitrypsin (AAT) levels. We aim to identify AATD in patients with chronic obstructive pulmonary disease (COPD), bronchiectasis, or asthma and to report the frequency of AAT variants in Turkey.

Patients and Methods

This non-interventional, multicenter, prospective study was conducted between October 2021 and June 2022. Adult patients with COPD, bronchiectasis, asthma, liver symptoms, or family members with AATD were included. Demographic and clinical characteristics, pulmonary diagnosis, respiratory symptoms, and AAT serum levels were assessed. Whole blood samples were collected as dried blood spots, and the most common AATD mutations were simultaneously tested by allele-specific genotyping.

Results

A total of 1088 patients, mainly diagnosed with COPD (92.7%) and shortness of breath (78.7%), were assessed. Fifty-one (5%) were found to have AATD mutations. Fifteen (29.4%) patients had Pi*S or Pi*Z mutations, whereas 36 (70.6%) patients carried rare alleles Pi*M malton (n=18, 35.3% of mutations), Pi*I (n=8, 16%), Pi*P lowell (n=7, 14%), Pi*M heerlen (n=2, 4%), and Pi*S iiyama (n=1, 2%). The most common heterozygous combinations were Pi*M/Z (n=12, 24%), and Pi*M/M malton (n=11, 22%). Ten patients with severe AATD due to two deficiency alleles were identified, two with the Pi*Z/Z genotype, four with the genotype Pi*M malton/M malton, three with Pi*Z/M malton, and one with Pi*Z/M heerlen.

Conclusion

Our results identified AATD mutations as a genetic-based contributor to lung disease in patients with COPD or bronchiectasis and assessed their frequency in a population of Turkish patients.

Liver disease progression in patients with alpha-1 antitrypsin deficiency and protease inhibitor ZZ genotype with or without lung disease

BACKGROUND

Alpha-1 antitrypsin deficiency (AATD) is caused by mutations in SERPINA1, which encodes alpha-1 antitrypsin, a protease inhibitor (Pi). Individuals with AATD and the homozygous Pi*ZZ genotype have variable risk of progressive liver disease but the influence of comorbid lung disease is poorly understood.

AIMS

To characterise patients with AATD Pi*ZZ and liver disease (AATD-LD-Pi*ZZ) with or without lung disease and describe liver disease-related clinical events longitudinally.

METHODS

This was an observational cohort study of patients in the Mayo Clinic Healthcare System (January 2000-September 2021). Patients were identified using diagnosis codes and natural language processing. Fibrosis stage (F0-F4) was assessed using a hierarchical approach at baseline (90 days before or after the index date) and follow-up. Clinical events associated with liver disease progression were assessed.

RESULTS

AATD-LD-Pi*ZZ patients with lung disease had a longer median time from AATD diagnosis to liver disease diagnosis versus those without lung disease (2.2 vs. 0.2 years, respectively). Compared to those without lung disease, patients with lung disease had a longer time to liver disease-related clinical events (8.5 years and not reached, respectively). AATD-LD-Pi*ZZ patients without lung disease were more likely to undergo liver transplantation compared with those with lung disease.

CONCLUSION

In patients with AATD and lung disease, there is a delay in the diagnosis of comorbid liver disease. Our findings suggest that liver disease may progress more rapidly in patients without comorbid lung disease.

Plant Serpins: Potential Inhibitors of Serine and Cysteine Proteases with Multiple Functions

Plant serpins are a superfamily of protein inhibitors that have been continuously studied in different species and have great biotechnological potential. However, despite ongoing studies with these inhibitors, the biological role of this family in the plant kingdom has not yet been fully clarified. In order to obtain new insights into the potential of plant serpins, this study presents the first systematic review of the topic, whose main objective was to scrutinize the published literature to increase knowledge about this superfamily. Using keywords and the eligibility criteria defined in the protocol, we selected studies from the Scopus, PubMed, and Web of Science databases. According to the eligible studies, serpins inhibit different serine and non-serine proteases from plants, animals, and pathogens, and their expression is affected by biotic and abiotic stresses. Moreover, serpins like AtSerpin1, OSP-LRS, MtSer6, AtSRP4, AtSRP5, and MtPiI4, act in resistance and are involved in stress-induced cell death in the plant. Also, the system biology analysis demonstrates that serpins are related to proteolysis control, cell regulation, pollen development, catabolism, and protein dephosphorylation. The information systematized here contributes to the design of new studies of plant serpins, especially those aimed at exploring their biotechnological potential.

Future Perspectives in the Diagnosis and Treatment of Liver Disease Associated with Alpha-1 Antitrypsin Deficiency

Alpha-1 antitrypsin deficiency (AATD) is one of the most common genetic diseases and is caused by mutations in the SERPINA1 gene. The homozygous Pi*Z variant is responsible for the majority of the classic severe form of alpha-1 antitrypsin deficiency, which is characterized by markedly decreased levels of serum alpha-1 antitrypsin (AAT) with a strong predisposition to lung and liver disease. The diagnosis and early treatment of AATD-associated liver disease are challenges in clinical practice. In this review, the authors aim to summarize the current evidence of the non-invasive methods in the assessment of liver fibrosis, as well as to elucidate the main therapeutic strategies under investigation that may emerge in the near future.

Genotypic Frequencies of Mutations Associated with Alpha-1 Antitrypsin Deficiency in Unrelated Bone Marrow Donors from the Murcia Region Donor Registry in the Southeast of Spain

Alpha-1 antitrypsin (AAT1) deficiency (AAT1D) is an inherited disease with an increased risk of chronic obstructive pulmonary disease (COPD), liver disease, and skin and blood vessel problems. AAT1D is caused by mutations in the SERPINE1 gene (Serine Protease Inhibitor, group A, member 1). Numerous variants of this gene, the Pi system, have been identified. The most frequent allelic variants are Pi*M, Pi*S, and Pi*Z. The development of COPD requires both a genetic predisposition and the contribution of an environmental factor, smoking being the most important. Studies on this deficiency worldwide are very scarce, and it is currently considered a rare disease because it is underdiagnosed. The aim of this study was to analyze the genotypic frequencies of mutations associated with AAT1 deficiency in unrelated bone marrow donors from the donor registry of the Region of Murcia in southeastern Spain due to the high risk of presenting with different pathologies and underdiagnosis in the population. A total of 112 DNA-healthy voluntary unrelated bone marrow donors from different parts of the Region of Murcia were analyzed retrospectively. AAT1 deficiency patient testing involved an automated biochemical screening routine. The three main variants, Pi*M, Pi*Z, and Pi*S, were analyzed in the SERPINE1 gene. Our results showed a frequency of 3.12% of the Pi*Z (K342) mutation in over 224 alleles tested in the healthy population. The frequency of Pi*S (V264) was 11.1%. The frequency of the haplotype with the most dangerous mutation, EK342 EE264, was 4.46%, and the frequency of EK342 EV264 was 1.78% in the healthy population. Frequencies of other EE342 EV264-mutated haplotypes accounted for 18.7%. As for the EE342 VV264 haplotype, 0.89% of the total healthy population presented heterozygous for the EV264 mutation and one individual presented homozygous for the VV264 mutation. In conclusion, the frequencies of Pi mutations in the healthy population of the Region of Murcia were not remarkably different from the few studies reported in Spain. The genotype and haplotype frequencies followed the usual pattern. Health authorities should be aware of this high prevalence of the Pi*S allelic variant and pathological genotypes such as Pi*MZ and Pi*SZ in the healthy population if they consider screening the smoking population.

Inflammatory biomarkers in the cervicovaginal fluid to identify histologic chorioamnionitis and funisitis in women with preterm labor

OBJECTIVE

We investigated the association between altered levels of inflammatory proteins in the cervicovaginal fluid (CVF) and acute histologic chorioamnionitis (HCA) and funisitis in women with preterm labor (PTL).

METHODS

In this study, a total of 134 consecutive singleton pregnant women with PTL (at 23+0-34+0 weeks) who delivered preterm (at  < 37 weeks) and from whom CVF samples were collected at admission were retrospectively enrolled. The CVF levels of haptoglobin, interleukin-6/8, kallistatin, lipocalin-2, matrix metalloproteinase (MMP)-8, resistin, S100 calcium-binding protein A8, and serpin A1 were determined using enzyme-linked immunosorbent assay. The placentas were histologically analyzed after delivery.

RESULTS

Multiple logistic regression analyses showed significant associations between elevated CVF interleukin-8 and resistin levels and acute HCA after adjusting for baseline covariates (e.g., gestational age at sampling). CVF haptoglobin, interleukin-6/8, kallistatin, MMP-8, and resistin levels were significantly higher in women with funisitis than in those without, whereas the baseline covariates were similar between the two groups (P > 0.1). The area under the receiver operating characteristic curves of the aforementioned biomarkers ranged from 0.61 to 0.77 regarding each outcome. Notably, HCA risk significantly increased with increasing CVF levels of interleukin-8 and resistin (P for trend  < 0.05).

CONCLUSIONS

Haptoglobin, interleukin-6/8, kallistatin, MMP-8, and resistin were identified as potential inflammatory CVF biomarkers predictive of acute HCA and funisitis in women with PTL. Moreover, the risk severity of acute HCA may be associated with the degree of the inflammatory response in the CVF (particularly based on interleukin-8 levels).

Could the Oxidation of α1-Antitrypsin Prevent the Binding of Human Neutrophil Elastase in COVID-19 Patients?

Human neutrophil elastase (HNE) is involved in SARS-CoV-2 virulence and plays a pivotal role in lung infection of patients infected by COVID-19. In healthy individuals, HNE activity is balanced by α1-antitrypsin (AAT). This is a 52 kDa glycoprotein, mainly produced and secreted by hepatocytes, that specifically inhibits HNE by blocking its activity through the formation of a stable complex (HNE-AAT) in which the two proteins are covalently bound. The lack of this complex, together with the detection of HNE activity in BALf/plasma samples of COVID-19 patients, leads us to hypothesize that potential functional deficiencies should necessarily be attributed to possible structural modifications of AAT. These could greatly diminish its ability to inhibit neutrophil elastase, thus reducing lung protection. The aim of this work was to explore the oxidation state of AAT in BALf/plasma samples from these patients so as to understand whether the deficient inhibitory activity of AAT was somehow related to possible conformational changes caused by the presence of abnormally oxidized residues.

Population genetic testing and SERPINA1 sequencing identifies unidentified alpha-1 antitrypsin deficiency alleles and gene-environment interaction with hepatitis C infection

Alpha-1 antitrypsin deficiency (AATD), a relatively common autosomal recessive genetic disorder, is underdiagnosed in symptomatic individuals. We sought to compare the risk of liver transplantation associated with hepatitis C infection with AATD heterozygotes and homozygotes and determine if SERPINA1 sequencing would identify undiagnosed AATD. We performed a retrospective cohort study in a deidentified Electronic Health Record (EHR)-linked DNA biobank with 72,027 individuals genotyped for the M, Z, and S alleles in SERPINA1. We investigated liver transplantation frequency by genotype group and compared with hepatitis C infection. We performed SERPINA1 sequencing in carriers of pathogenic AATD alleles who underwent liver transplantation. Liver transplantation was associated with the Z allele (ZZ: odds ratio [OR] = 1.31, p<2e-16; MZ: OR = 1.02, p = 1.2e-13) and with hepatitis C (OR = 1.20, p<2e-16). For liver transplantation, there was a significant interaction between genotype and hepatitis C (ZZ: interaction OR = 1.23, p = 4.7e-4; MZ: interaction OR = 1.11, p = 6.9e-13). Sequencing uncovered a second, rare, pathogenic SERPINA1 variant in six of 133 individuals with liver transplants and without hepatitis C. Liver transplantation was more common in individuals with AATD risk alleles (including heterozygotes), and AATD and hepatitis C demonstrated evidence of a gene-environment interaction in relation to liver transplantation. The current AATD screening strategy may miss diagnoses whereas SERPINA1 sequencing may increase diagnostic yield for AATD, stratify risk for liver disease, and inform clinical management for individuals with AATD risk alleles and liver disease risk factors.

Improving Detection of Alpha-1 Antitrypsin Deficiency: Role of the Allergist

Alpha-1 antitrypsin deficiency (AATD) is a genetic disorder that manifests as lung and/or liver disease. Because symptoms of AATD overlap with those of common pulmonary and hepatic conditions, AATD is often misdiagnosed, which has resulted in substantial underdiagnosis of AATD worldwide. Although screening patients for AATD is recommended, the lack of procedures to facilitate testing remains a barrier to accurate diagnosis of AATD. Delays in AATD diagnosis can worsen outcomes for patients by postponing appropriate disease-modifying treatments. Patients with AATD-related lung disease experience symptoms similar to other obstructive lung disorders and are often misdiagnosed for years. In addition to existing screening guidelines, we recommend that screening for AATD become a standard part of allergists' workups of patients with asthma and fixed obstructive disease, chronic obstructive pulmonary disease, bronchiectasis without known origin, and patients under consideration for treatment with biologics. This Rostrum article reviews screening and diagnostic tests available in the United States and emphasizes evidence-based strategies to increase testing frequency and improve AATD detection rates. We underscore the pivotal role of allergists in managing care for patients with AATD. Finally, we urge health care providers to be aware of potentially poor clinical outcomes among patients with AATD during the coronavirus disease 2019 pandemic.

Association of A1AT genetic polymorphism and NSCLC: a case- control study in Egyptian population

BACKGROUND

Lung cancer mortality is higher than other forms of cancer. Genetic tendencies in cancer patients have long been known. Given the link between A1ATD and numerous lung disorders, it is worth investigating if this genetic trait is linked to a higher risk of developing LC, as the lung is the most afflicted organ in individuals with severe A1ATD. This study is intended to investigate the possible association between AAT rs17580 and rs8004738 gene polymorphisms and susceptibility to non-small cell lung cancer for early prediction in Egyptians.

METHODS

A case-control study was performed on 124 NSCLC cases and 124 healthy controls from 2021 to 2022 in the oncology center of Mansoura University. Peripheral blood was used to obtain genomic DNA. ARMS-PCR was used to genotype SNPs and other chemical parameters. Windows SPSS Statistics was used to review, encode, and tabulate the acquired data.

RESULTS

A molecular study for A1AT rs17580 and rs8004738 genotypes showed that NSCLC cases were significantly associated with a higher proportion of mutant S (T) and mutant Z (A) alleles (p = 0.042, 0.041, respectively). Different A1AT genotypes (MS, MZ, SS, SZ, and ZZ) showed no significant association with NSCLC or NLR.

CONCLUSION

S and Z alleles might have significant impacts on NSCLC risk and can be useful for detecting and protecting individuals who may be vulnerable to carcinogens. Further research with larger sample sizes is needed to confirm the current findings.

Astrocyte-derived SerpinA3N promotes neuroinflammation and epileptic seizures by activating the NF-κB signaling pathway in mice with temporal lobe epilepsy

Impaired activation and regulation of the extinction of inflammatory cells and molecules in injured neuronal tissues are key factors in the development of epilepsy. SerpinA3N is mainly associated with the acute phase response and inflammatory response. In our current study, transcriptomics analysis, proteomics analysis, and Western blotting showed that the expression level of Serpin clade A member 3N (SerpinA3N) is significantly increased in the hippocampus of mice with kainic acid (KA)-induced temporal lobe epilepsy, and this molecule is mainly expressed in astrocytes. Notably, in vivo studies using gain- and loss-of-function approaches revealed that SerpinA3N in astrocytes promoted the release of proinflammatory factors and aggravated seizures. Mechanistically, RNA sequencing and Western blotting showed that SerpinA3N promoted KA-induced neuroinflammation by activating the NF-κB signaling pathway. In addition, co-immunoprecipitation revealed that SerpinA3N interacts with ryanodine receptor type 2 (RYR2) and promotes RYR2 phosphorylation. Overall, our study reveals a novel SerpinA3N-mediated mechanism in seizure-induced neuroinflammation and provides a new target for developing neuroinflammation-based strategies to reduce seizure-induced brain injury.

Electrochemical Disposable Biosensor to Monitor Dabigatran in Point-of-Care Anticoagulation Therapy

Dabigatran etexilate, an oral prodrug, is often used to treat complications linked to thrombosis. Dabigatran (DAB, active form) does not need to be monitored. However, there are several conditions, such as reduced renal function, traumatic bleeding, emergency surgery, the need for thrombolytic therapy in acute stroke, or the requirement to use other forms of anticoagulation, where knowing the concentration of DAB in the blood is indispensable. Unfortunately, there are no convenient DAB-specific point-of-care tests available. To solve this problem, two disposable sensors were constructed and optimised in this work to detect the anticoagulant drug DAB using novel co-facing disposable electrodes, which allows a calibration-free quantitation of the electroactive mediator concentration. A trypsin-based sensor was evaluated. This sensor performed well in a 10 mM Tris buffer (pH 8.8) solution. However, trypsin was inhibited by alpha-1 antitrypsin when a plasma sample was introduced into the sensor. This problem was overcome by plasma filtration. This sensor showed a detection limit of 50.7 ng mL^-1 DAB in plasma and a quantification range of 177-500 ng mL^-1. A thrombin-based sensor was also constructed. This sensor performed well in ten-fold diluted plasma, overcoming the filtration problem observed with the trypsin-based sensor. This sensor showed a detection limit of 9.6 ng mL^-1 DAB in plasma and a quantification range of 11.5-140 ng mL^-1. Its extensive pH stability range, the possibility of working at physiological pH, low volume, low cost, and fast turnaround response (less than 20 s) make the calibration-free thrombin-based sensor a suitable point-of-care test to measure DAB concentration in the blood.

The serum proteome of VA-ECMO patients changes over time and allows differentiation of survivors and non-survivors: an observational study

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is applied in patients with refractory hemodynamic failure. Exposure of blood components to high shear stress and the large extracorporeal surfaces in the ECMO circuit trigger a complex inflammatory response syndrome and coagulopathy which are believed to worsen the already poor prognosis of these patients. Mass spectrometry-based proteomics allow a detailed characterization of the serum proteome as it provides the identity and concentration of large numbers of individual proteins at the same time. In this study, we aimed to characterize the serum proteome of patients receiving VA-ECMO.

METHODS

Serum samples were collected on day 1 and day 3 after initiation of VA-ECMO. Samples underwent immunoaffinity based depletion for the 14 most abundant serum proteins, in-solution digestion and PreOmics clean-up. A spectral library was built with multiple measurements of a master-mix sample using variable mass windows. Individual samples were measured in data independent acquisition (DIA) mode. Raw files were analyzed by DIA-neural network. Unique proteins were log transformed and quantile normalized. Differential expression analysis was conducted with the LIMMA-R package. ROAST was applied to generate gene ontology enrichment analyses.

RESULTS

Fourteen VA-ECMO patients and six healthy controls were recruited. Seven patients survived. Three hundred and fifty-one unique proteins were identified. One hundred and thirty-seven proteins were differentially expressed between VA-ECMO patients and controls. One hundred and forty-five proteins were differentially expressed on day 3 compared to day 1. Many of the differentially expressed proteins were involved in coagulation and the inflammatory response. The serum proteomes of survivors and non-survivors on day 3 differed from each other according to partial least-squares discriminant analysis (PLS-DA) and 48 proteins were differentially expressed. Many of these proteins have also been ascribed to processes in coagulation and inflammation (e.g., Factor IX, Protein-C, Kallikrein, SERPINA10, SEMA4B, Complement C3, Complement Factor D and MASP-1).

CONCLUSION

The serum proteome of VA-ECMO patients displays major changes compared to controls and changes from day 1 until day 3. Many changes in the serum proteome are related to inflammation and coagulation. Survivors and non-survivors can be differentiated according to their serum proteomes using PLS-DA analysis on day 3. Our results build the basis for future studies using mass-spectrometry based serum proteomics as a tool to identify novel prognostic biomarkers.

TRIAL REGISTRATION

DRKS00011106.

Alpha-1-antitrypsin and its variant-dependent role in COVID-19 pathogenesis

Rationale

SARS-CoV-2 entry into host cells is facilitated by endogenous and exogenous proteases that proteolytically activate the spike glycoprotein and antiproteases inhibiting this process. Understanding the key actors in viral entry is crucial for advancing knowledge of virus tropism, pathogenesis, and potential therapeutic targets.

Objectives

We aimed to investigate the role of naïve serum and alpha-1-antitrypsin (AAT) in inhibiting protease-mediated SARS-CoV-2 entry and explore the implications of AAT deficiency on susceptibility to different SARS-CoV-2 variants.

Findings

Our study demonstrates that naïve serum exhibits significant inhibition of SARS-CoV-2 entry, with AAT identified as the major serum protease inhibitor potently restricting entry. Using pseudoparticles, replication-competent pseudoviruses, and authentic SARS-CoV-2, we show that AAT inhibition occurs at low concentrations compared with those in serum and bronchoalveolar tissues, suggesting physiological relevance. Furthermore, sera from subjects with an AAT-deficient genotype show reduced ability to inhibit entry of both Wuhan-Hu-1 (WT) and B.1.617.2 (Delta) but exhibit no difference in inhibiting B.1.1.529 (Omicron) entry.

Conclusions

AAT may have a variant-dependent therapeutic potential against SARS-CoV-2. Our findings highlight the importance of further investigating the complex interplay between proteases, antiproteases, and spike glycoprotein activation in SARS-CoV-2 and other respiratory viruses to identify potential therapeutic targets and improve understanding of disease pathogenesis.

Label-free quantitative proteomics reveals aberrant expression levels of LRG, C9, FN, A1AT and AGP1 in the plasma of patients with colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the major causes of cancer-related death worldwide. Although commercial biomarkers of CRC are currently available, they are still lacking in terms of sensitivity and specificity; thus, searching for reliable blood-based biomarkers are important for the primary screening of CRC.

METHODS

Plasma samples of patients with non-metastatic (NM) and metastatic (M) CRC and healthy controls were fractionated using MARS-14 immunoaffinity chromatography. The flow-through and elute fractions representing low- and high-abundant proteins, respectively, were analyzed by label-free quantitative proteomics mass spectrometry. The functional analysis of the proteins with greater than 1.5-fold differential expression level between the CRC and the healthy control groups were analyzed for their biological processes and molecular functions. In addition, the levels of plasma proteins showing large alterations in CRC patients were confirmed by immunoblotting using two independent cohorts. Moreover, receiver operating characteristic (ROC) curve analysis was performed for individual and combinations of biomarker candidates so as to evaluate the diagnostic performance of biomarker candidates.

RESULTS

From 163 refined identifications, five proteins were up-regulated and two proteins were down-regulated in NM-CRC while eight proteins were up-regulated and three proteins were down-regulated in M-CRC, respectively. Altered plasma proteins in NM-CRC were mainly involved in complement activation, while those in M-CRC were clustered in acute-phase response, complement activation, and inflammatory response. Results from the study- and validation-cohorts indicate that the levels of leucine-rich alpha-2-glycoprotein-1(LRG), complement component C9 (C9), alpha-1-acid glycoprotein 1 (AGP1), and alpha-1-antitrypsin (A1AT) were statistically increased, while fibronectin (FN) level was statistically decreased in CRC patients compared to healthy controls, with most alterations found in a metastatic stage-dependent manner. ROC analysis revealed that FN exhibited the best diagnostic performance to discriminate CRC patients and healthy controls while AGP1 showed the best discrimination between the disease stages in both cohorts. The combined biomarker candidates, FN + A1AT + AGP1, exhibited perfect discriminatory power to discriminate between the CRC population and healthy controls whereas LRG + A1AT + AGP1 was likely to be the best panel to discriminate the metastatic stages in both cohorts.

CONCLUSIONS

This study identified and quantified distinct plasma proteome profiles of CRC patients. Selected CRC biomarker candidates including FN, LRG, C9, A1AT, and AGP1 may be further applied for screening larger cohorts including disease groups from other types of cancer or other diseases.

Role of liver parameters in diabetes mellitus - a narrative review

Diabetes mellitus is characterized by hyperglycemia and abnormalities in insulin secretion and function. This review article focuses on various liver parameters, including albumin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), alpha fetoprotein (AFP), alpha 1 antitrypsin (AAT), ammonia, bilirubin, bile acid, gamma-glutamyl transferase (GGT), immunoglobulin, lactate dehydrogenase (LDH), and total protein. These parameters play significant roles in the development of different types of diabetes such as type 1 diabetes (T1DM), type 2 diabetes (T2DM) and gestational diabetes (GDM). The article highlights that low albumin levels may indicate inflammation, while increased ALT and AST levels are associated with liver inflammation or injury, particularly in non-alcoholic fatty liver disease (NAFLD). Elevated ALP levels can be influenced by liver inflammation, biliary dysfunction, or bone metabolism changes. High bilirubin levels are independently linked to albuminuria in T1DM and an increased risk of T2DM. Elevated GGT levels are proposed as markers of oxidative stress and liver dysfunction in T2DM. In GDM, decreased serum AFP levels may indicate impaired embryo growth. Decreased AFP levels in T2DM can hinder the detection of hepatocellular carcinoma. Hyperammonemia can cause encephalopathy in diabetic ketoacidosis, and children with T1DM and attention deficit hyperactivity disorder often exhibit higher ammonia levels. T2DM disrupts the regulation of nitrogen-related metabolites, leading to increased blood ammonia levels. Bile acids affect glucose regulation by activating receptors on cell surfaces and nuclei, and changes in bile acid metabolism are observed in T2DM. Increased LDH activity reflects metabolic disturbances in glucose utilization and lactate production, contributing to diabetic complications. Poor glycemic management may be associated with elevated levels of IgA and IgG serum antibodies, and increased immunoglobulin levels are also associated with T2DM.

Comparison of COVID-19 Outcomes With Alpha-1 Antitrypsin Deficiency Prevalence in Europe: A Cross-Sectional Study

Introduction We hypothesized that the geographic distributions of COVID-19 and alpha-1 antitrypsin alleles prevalence are similar. We investigate whether there is a relationship between the geographical density of the COVID-19 pandemic and the distributions of alpha-1 antitrypsin alleles. Methods This research is a cross-sectional study. Alpha-1 antitrypsin PI*MS, PI*MZ, PI*SS, PI*SZ, and PI*ZZ genotypes frequencies of European countries were compared with the case and death data related to the COVID-19 pandemic as of March 1, 2022.  Results A significant relationship was found between the rates of COVID-19 cases and the rates of individuals with alpha-1 antitrypsin PI*MS, PI*MZ, PI*SS, PI*SZ, and PI*ZZ genotypes allele in European countries. Conclusions The findings showed that the prevalence distribution of the alleles of the gene defect that causes alpha-1 antitrypsin insufficiency is related to the prevalence of COVID-19 pandemic data.

COVID-19 Pathology Sheds Further Light on Balance between Neutrophil Proteases and Their Inhibitors

Excessive neutrophil influx and activation in lungs during infections, such as manifest during the ongoing SARS CoV-2 pandemic, have brought neutrophil extracellular traps (NETs) and the concomitant release of granule contents that damage surrounding tissues into sharp focus. Neutrophil proteases, which are known to participate in NET release, also enable the binding of the viral spike protein to cellular receptors and assist in the spread of infection. Blood and tissue fluids normally also contain liver-derived protease inhibitors that balance the activity of proteases. Interestingly, neutrophils themselves also express the protease inhibitor alpha-1-antitrypsin (AAT), the product of the SERPINA-1 gene, and store it in neutrophil cytoplasmic granules. The absence of AAT or mutations in the SERPINA-1 gene promotes lung remodeling and fibrosis in diseases such as chronic obstructive pulmonary disease (COPD), and acute respiratory distress syndrome (ARDS) and increases the risk of allergic responses. Recent observations point to the fact that reduced activity of AAT presents a major susceptibility factor for severe COVID-19. Here, we focus attention on the mechanism of neutrophil elastase (NE) in NET release and its inhibition by AAT as an additional factor that may determine the severity of COVID-19.

The role of lung macrophages in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) as a common, preventable and treatable chronic respiratory disease in clinic, gets continuous deterioration and we can't take effective intervention at present. Lung macrophages (LMs) are closely related to the occurrence and development of COPD, but the specific mechanism is not completely clear. In this review we will focus on the role of LMs and potential avenues for therapeutic targeting for LMs in COPD.

Proteolysis and Deficiency of α1-Proteinase Inhibitor in SARS-CoV-2 Infection

The SARS-CoV-2 pandemic had stimulated the emergence of numerous publications on the α1-proteinase inhibitor (α1-PI, α1-antitrypsin), especially when it was found that the regions of high mortality corresponded to the regions with deficient α1-PI alleles. By analogy with the data obtained in the last century, when the first cause of the genetic deficiency of α1-antitrypsin leading to elastase activation in pulmonary emphysema was proven, it can be supposed that proteolysis hyperactivation in COVID-19 may be associated with the impaired functions of α1-PI. The purpose of this review was to systematize the scientific data and critical directions for translational studies on the role of α1-PI in SARS-CoV-2-induced proteolysis hyperactivation as a diagnostic marker and a therapeutic target. This review describes the proteinase-dependent stages of viral infection: the reception and penetration of the virus into a cell and the imbalance of the plasma aldosterone-angiotensin-renin, kinin, and blood clotting systems. The role of ACE2, TMPRSS, ADAM17, furin, cathepsins, trypsin- and elastase-like serine proteinases in the virus tropism, the activation of proteolytic cascades in blood, and the COVID-19-dependent complications is considered. The scientific reports on α1-PI involvement in the SARS-CoV-2-induced inflammation, the relationship with the severity of infection and comorbidities were analyzed. Particular attention is paid to the acquired α1-PI deficiency in assessing the state of patients with proteolysis overactivation and chronic non-inflammatory diseases, which are accompanied by the risk factors for comorbidity progression and the long-term consequences of COVID-19. Essential data on the search and application of protease inhibitor drugs in the therapy for bronchopulmonary and cardiovascular pathologies were analyzed. The evidence of antiviral, anti-inflammatory, anticoagulant, and anti-apoptotic effects of α1-PI, as well as the prominent data and prospects for its application as a targeted drug in the SARS-CoV-2 acquired pneumonia and related disorders, are presented.

α1-Antitrypsin Binds to the Glucocorticoid Receptor with Anti-Inflammatory and Antimycobacterial Significance in Macrophages

α1-Antitrypsin (AAT), a serine protease inhibitor, is the third most abundant protein in plasma. Although the best-known function of AAT is irreversible inhibition of elastase, AAT is an acute-phase reactant and is increasingly recognized to have a panoply of other functions, including as an anti-inflammatory mediator and a host-protective molecule against various pathogens. Although a canonical receptor for AAT has not been identified, AAT can be internalized into the cytoplasm and is known to affect gene regulation. Because AAT has anti-inflammatory properties, we examined whether AAT binds the cytoplasmic glucocorticoid receptor (GR) in human macrophages. We report the finding that AAT binds to GR using several approaches, including coimmunoprecipitation, mass spectrometry, and microscale thermophoresis. We also performed in silico molecular modeling and found that binding between AAT and GR has a plausible stereochemical basis. The significance of this interaction in macrophages is evinced by AAT inhibition of LPS-induced NF-κB activation and IL-8 production as well as AAT induction of angiopoietin-like 4 protein, which are, in part, dependent on GR. Furthermore, this AAT-GR interaction contributes to a host-protective role against mycobacteria in macrophages. In summary, this study identifies a new mechanism for the gene regulation, anti-inflammatory, and host-defense properties of AAT.

Novel insights into the relationship between α-1 anti-trypsin with the pathological development of cardio-metabolic disorders

According to the previous studies, chronic low-grade systemic inflammatory response has been shown to be significantly associated with the pathological development of cardio-metabolic disorder diseases, including atherosclerosis, type 2 diabetes mellitus, and non-alcoholic fatty liver disease (NAFLD). On the other hand, auto-immunity process could also facilitate the pathogenesis of type 1 diabetes mellitus importantly. Concerning on this notion, the anti-inflammatory therapeutic strategy is demonstrated to embrace an essential function in those cardio-metabolic disorders in clinical practice. The α-1 anti-trypsin, also named Serpin-A1 and as an acute phase endogenous protein, has been verified to have several modulatory effects such as anti-inflammatory response, anti-apoptosis, and immunomodulatory functions. In addition, it is also used for therapeutic strategy of a rare genetic disease caused by the deficiency of α-1 anti-trypsin. Recent emerging evidence has indicated that the serum concentrations of α-1 anti-trypsin levels and its biological activity are significantly changed in those inflammatory and immune related cardio-metabolic disorder diseases. Nevertheless, the underlying mechanism is still not elucidated. In the current review, the basic experiments and clinical trials which provided the evidence revealing the potential therapeutic function of the α-1 anti-trypsin in cardio-metabolic disorder diseases were well-summarized. Furthermore, the results which indicated that the α-1 anti-trypsin presented the possibility as a novel serum biomarker in humans to predict those cardio-metabolic disorder diseases were also elucidated.

Alpha-1 antitrypsin in autoimmune diseases: Roles and therapeutic prospects

Alpha-1 antitrypsin (A1AT) is a protease inhibitor in the serum. Its primary function is to inhibit the activity of a series of proteases, including proteinase 3, neutrophil elastase, metalloproteases, and cysteine-aspartate proteases. In addition, A1AT also has anti-inflammatory, anti-apoptotic, anti-oxidative stress, anti-viral, and anti-bacterial activities and plays essential roles in the regulation of tissue repair and lymphocyte differentiation and activation. The overactivation of the immune system characterizes the pathogenesis of autoimmune diseases. A1AT treatment shows beneficial effects on patients and animal models with autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus. This review summarizes the functions and therapeutic prospects of A1AT in autoimmune diseases.

Common genetic variation associated with Mendelian disease severity revealed through cryptic phenotype analysis

Clinical heterogeneity is common in Mendelian disease, but small sample sizes make it difficult to identify specific contributing factors. However, if a disease represents the severely affected extreme of a spectrum of phenotypic variation, then modifier effects may be apparent within a larger subset of the population. Analyses that take advantage of this full spectrum could have substantially increased power. To test this, we developed cryptic phenotype analysis, a model-based approach that infers quantitative traits that capture disease-related phenotypic variability using qualitative symptom data. By applying this approach to 50 Mendelian diseases in two cohorts, we identify traits that reliably quantify disease severity. We then conduct genome-wide association analyses for five of the inferred cryptic phenotypes, uncovering common variation that is predictive of Mendelian disease-related diagnoses and outcomes. Overall, this study highlights the utility of computationally-derived phenotypes and biobank-scale cohorts for investigating the complex genetic architecture of Mendelian diseases.

Quantitative glycoproteomics of high-density lipoproteins

In this work, we developed a targeted glycoproteomic method to monitor the site-specific glycoprofiles and quantities of the most abundant HDL-associated proteins using Orbitrap LC-MS for (glyco)peptide target discovery and QqQ LC-MS for quantitative analysis. We conducted a pilot study using the workflow to determine whether HDL protein glycoprofiles are altered in healthy human participants in response to dietary glycan supplementation.

Specific Cerebrospinal Fluid SerpinA1 Isoform Pattern in Alzheimer's Disease

SerpinA1 (α1-antitrypsin) is a soluble glycoprotein, the cerebrospinal fluid (CSF) isoforms of which showed disease-specific changes in neurodegenerative disorders that are still unexplored in Alz-heimer’s disease (AD). By means of capillary isoelectric focusing immunoassay, we investigated six serpinA1 isoforms in CSF samples of controls (n = 29), AD-MCI (n = 29), AD-dem (n = 26) and Lewy body disease (LBD, n = 59) patients and correlated the findings with CSF AD core biomarkers (Aβ42/40 ratio, p-tau, t-tau). Four CSF serpinA1 isoforms were differently expressed in AD patients compared to controls and LBD patients, especially isoforms 2 and 4. AD-specific changes were found since the MCI stage and significantly correlated with decreased Aβ42/40 (p < 0.05) and in-creased p-tau and t-tau levels in CSF (p < 0.001). Analysis of serpinA1 isoform provided good di-agnostic accuracy in discriminating AD patients versus controls (AUC = 0.80) and versus LBD patients (AUC = 0.92), with best results in patients in the dementia stage (AUC = 0.97). SerpinA1 isoform expression is altered in AD patients, suggesting a common, albeit disease-specific, in-volvement of serpinA1 in most neurodegenerative disorders.