Alpha-1 Antitrypsin Treatment Research Articles

Alpha-1 antitrypsin targeted neutrophil elastase protects against sepsis-induced inflammation and coagulation in mice via inhibiting neutrophil extracellular trap formation

AimsSepsis pathophysiology is complex and identifying effective treatments for sepsis remains challenging. The study aims to identify effective drugs and targets for sepsis through transcriptomic analysis of sepsis patients, repositioning analysis of compounds, and validation by animal models. Main methodsGSE185263 obtained from the GEO database that includes gene expression profiles of 44 healthy controls and 348 sepsis patients categorized by severity. Bioinformatic algorithms revealed the molecular, function, and immune characteristics of the sepsis, and constructed sepsis-related protein-protein interaction networks. Subsequently, Random Walk with Restart analysis was applied to identify candidate drugs for sepsis, which were tested in animal models for survival, inflammation, coagulation, and multi-organ damage. Key findingsOur analysis found 1862 genes linked to sepsis development, enriched in functions like neutrophil extracellular trap formation (NETs) and complement/coagulation cascades. With disease progression, immune activation-associated cells were inhibited, while immune suppression-associated cells were activated. Next, the drug repositioning method identified candidate drugs, such as alpha-1 antitrypsin, that may play a therapeutic role by targeting neutrophil elastase (NE) to inhibit NETs. Animal experiments proved that alpha-1 antitrypsin treatment can improve the survival rate, reduce sepsis score, reduce the levels of inflammation markers in serum, and alleviate muti-organ morphological damage in mice with sepsis. The further results showed that α-1 antitrypsin can inhibit the NETs by suppressing the NE for the treatment of sepsis. SignificanceAlpha-1 antitrypsin acted on the NE to inhibit NETs thereby protecting mice from sepsis-induced inflammation and coagulation.

KF4 Anti-Chymotrypsin-like Elastase 1 Antibody and Purified Alpha-1 Antitrypsin Have Similar but Not Additive Efficacy in Preventing Emphysema in Murine Alpha-1 Antitrypsin Deficiency.

Alpha-1 antitrypsin (AAT) deficiency is the most common genetic cause of emphysema. Chymotrypsin-like Elastase 1 (CELA1) is a serine protease neutralized by AAT and is important in emphysema progression. Cela1-deficiency is protective in a murine models of AAT-deficient emphysema. KF4 anti-CELA1 antibody prevented emphysema in porcine pancreatic elastase (PPE) and cigarette smoke models in wild type mice. We evaluated potential toxicities of KF4 and its ability to prevent emphysema in AAT deficiency. We found Cela1 protein expression in mouse lung, pancreas, small intestine, spleen, and bone marrow. In toxicity studies, mice treated with KF4 25 mg/kg weekly for four weeks showed an elevation in blood urea nitrogen and slower weight gain compared to lower doses or equivalent dose IgG. By histologic grading of tissue injury of the lung, kidney, liver, and heart, there was some evidence of liver injury with KF4 25 mg/kg, but in all tissues, injury was less than in control mice subjected to cecal ligation and puncture. In efficacy studies, KF4 doses as low as 0.5 mg/kg reduced the lung elastase activity of AAT-/- mice treated with 0.2 units of PPE. In this injury model, AAT-/- mice treated with KF4 1 mg/kg weekly, human purified AAT 60 mg/kg weekly, and combined KF4 and AAT treatment had less emphysema than mice treated with IgG 1 mg/kg weekly. However, the efficacy of KF4, AAT, or KF4 & AAT was similar. While KF4 might be an alternative to AAT replacement, combined KF4 and AAT replacement does not confer additional benefit.

201.2: No differences in long-term diabetes outcomes with etanercept or alpha-1 antitrypsin treatment in total pancreatectomy and islet autotransplantation: A randomized controlled pilot study

201.2: No differences in long-term diabetes outcomes with etanercept or alpha-1 antitrypsin treatment in total pancreatectomy and islet autotransplantation: A randomized controlled pilot study

Alpha-1 antitrypsin deficiency: epidemiology, etiology, pathophysiology, clinical manifestation, diagnosis, treatment (literature review)

Gabija Žemgulytė1, Aistė Šidlauskaitė1, Miglė Jurgelėnaitė2 1 Lithuanian University of Health Sciences, Faculty of Medicine, Kaunas, Lithuania 2 Lithuanian University of Health Sciences Kaunas Clinics, Department of Pulmonology, Kaunas, Lithuania Abstract Introduction. Alpha-1 antitrypsin (A1AT) is a glycoprotein that protects the body’s tissues from damage caused by substances released by the immune system. It’s deficiency is one of the most common genetic diseases that is underdiagnosed. The main clinical manifestations of A1AT deficiency involve damage to the lungs, liver and rarely the skin. Lung damage can put people at risk for obstructive pulmonary disease (COPD), while liver damage can be manifested by cholestasis, cirrhosis, and increased risk of hepatocellular carcinoma. Aim: to review the epidemiology, etiology, pathophysiology, clinic, diagnosis and treatment options of alpha-1 antitrypsin deficiency. Materials and methods: a literature review was performed using PubMed, Science direct and other databases. Keywords used in the search: alpha-1 antitrypsin; alpha-1 antitrypsin deficiency; AATD; SERPINA1; COPD; hepatic cirrhosis. Articles and clinical case publications up to five years old were selected for analysis. The results are described in terms of etiology, pathophysiology, clinical presentation, diagnosis and treatment. Results: approximately 1 in 2,500 people worldwide suffer from alpha-1 antitrypsin deficiency, but most of them are undiagnosed. This genetic disorder can cause damage to the lungs, liver or, less commonly, to the skin. Conclusions: alpha-1 antitrypsin deficiency remains largely undiagnosed because the clinical symptoms of this pathology are not specific. To confirm the diagnosis, blood levels of alpha-1 antitrypsin protein should be determined. Specific treatment is only available for patients with lung damage. Keywords: alpha-1 antitrypsin deficiency, COPD, cirrhosis, A1AT diagnosis, A1AT treatment.

Improving the Lives of Patients with Alpha-1 Antitrypsin Deficiency.

Alpha-1 Antitrypsin Deficiency (AATD) is a rare genetic condition that predisposes patients to lung and liver disease and is often underdiagnosed due to incomplete diagnosis of chronic obstructive pulmonary disease (COPD) and asthma. Improvements in physician awareness have been made, but better strategies for both diagnosis and management are still required. The only current disease-modifying therapy for AATD is the infusion of the missing Alpha-1 Antitrypsin (AAT) protein, which can slow progression of emphysema. However, AAT treatment can impact patient freedom and quality of life due to the need for weekly intravenous infusions. A symposium was held to discuss patient-centric aspects of care that have impact on the lives of patients with AATD, including exacerbations of their lung disease, self-administration of intravenous AAT therapy and pulmonary rehabilitation. Intravenous self-infusion of drugs is an established treatment strategy for patients with a variety of conditions and can improve patient quality of life, freedom and mental well-being. Experience from these areas show that patients typically manage their treatment well and without complications. When applied to AATD, training patients to self-infuse therapy can be successful, but formal guidelines would be beneficial. In addition to pharmacological intervention, individualized pulmonary rehabilitation, exercise and educational programs can encourage health-enhancing patient behavior and further improve patient quality of life. However, differences in skeletal muscle adaptations to pulmonary rehabilitation exercise regimens have been observed between patients with AATD and non-AATD COPD, highlighting the need to develop training programs specifically designed for patients with AATD.

Human-Derived α1-Antitrypsin is Still Efficacious in Heavily Pretreated Patients with Steroid-Resistant Gastrointestinal Graft-versus-Host Disease.

Almost one-half of patients developing graft-versus-host disease (GVHD) will not respond to standard first-line steroid treatment. Alpha-1 antitrypsin (AAT) is able to induce tolerance in preclinical models of GVHD. AAT alters the cytokine milieu, promotes a tolerogenic shift of dendritic cells, and skews effector T cells toward regulatory T cells. Gastrointestinal steroid-refractory (SR)-GVHD is a protein-losing enteropathy that might represent the optimal setting in which to use AAT. Here we analyze the outcomes of 16 patients treated with human-derived AAT in advanced-stage gut SR-GVHD, with two-thirds of the patients having failed at least 1 treatment for SR-GVHD. The overall response rate (ORR) was 44%, with a complete response (CR) rate of 27%. Gastrointestinal response was observed in 61% of patients. The median time to best response was 21 days (range, 6 to 26 days). At day 56 after AAT treatment, all CRs were maintained, and the ORR was 39%. The 1-year overall survival was 48% (95% confidence interval, 26% to 74%). Ancillary studies showed that AAT serum levels were in the normal range at the beginning of treatment, whereas fecal loss was elevated. AAT levels consistently rose after exogenous administration, but no correlation was found between serum levels and response. REG3α and IL-33 levels were associated with response while, in contrast to previous reports, regulatory T cells decreased during AAT treatment. This retrospective analysis supports a previous report of AAT as a promising agent in the management of gut SR-GVHD and should prompt its evaluation at an earlier stage.

Improving engraftment of hepatocyte transplantation using alpha-1 antitrypsin as an immune modulator

For patients with non-cirrhotic liver-based metabolic disorders, hepatocyte transplantation can be an effective treatment. However, long-term function of transplanted hepatocytes following infusion has not been achieved due to insufficient numbers of hepatocytes reaching the liver cell plates caused by activation of the instant blood-mediated inflammatory reaction (IBMIR). Our aim was to determine if the natural immune modulator, alpha-1 antitrypsin (AAT), could improve engraftment of transplanted hepatocytes and investigate its mechanism of action. A tubing loop model was used to analyse activation of the IBMIR when human hepatocytes were in contact with ABO-matched blood and 4 mg/ml AAT. Platelet and white cell counts, complement and cytokine expression were analysed. To determine if AAT could improve short-term engraftment, female rats underwent tail vein injection of AAT (120 mg/kg) or water (control) prior to the intrasplenic transplantation of 2 × 107 male hepatocytes. At 48 h and 1 week, livers were collected for analysis. In our loop model, human hepatocytes elicited a significant drop in platelet count with thrombus formation compared to controls. Loops containing AAT and hepatocytes showed no platelet consumption and no thrombus formation. Further, AAT treatment resulted in reduced IL-1β, IL-6 and IFN-γ and increased IL-1RA compared to untreated loops. In vivo, AAT significantly improved engraftment of rat hepatocytes compared to untreated at 48 h. AAT infusion may inhibit the IBMIR, thus improving short-term engraftment of donor hepatocytes and potentially improve the outcomes for patients with liver-based metabolic disease.Key messages• Alpha-1 antitrypsin (AAT) acts as an immune modulator to improve the efficacy of hepatocyte transplantation.• Treatment with AAT decreased thrombus formation and pro-inflammatory cytokine expression in a tubing loop model.• AAT significantly improved engraftment of donor hepatocytes within the first 48 h post transplantation.

Therapeutic potential of alpha-1 antitrypsin in human disease.

Alpha-1 antitrypsin (AAT), an alpha globulin glycoprotein, is a member of the serine protease inhibitor (serpin) superfamily. The clinical significance of AAT is highlighted by AAT deficiency. Genetic deficiency of AAT can present as several neutrophilic diseases associated with emphysema, liver cirrhosis, panniculitis, and systemic vasculitis. Recently, animal and human studies have shown that AAT can control inflammatory, immunological, and tissue-protective responses. In addition, AAT treatment can prevent overt hyperglycemia, increase insulin secretion, and reduce cytokine-mediated apoptosis of pancreatic β-cells in diabetes. These multifunctional roles of AAT draw attention to the glycoprotein’s therapeutic potential for many inflammatory and autoimmune diseases beyond AAT deficiency. As underlying mechanisms, recent studies have suggested the importance of serine protease inhibitory activity of AAT in obesity-associated insulin resistance, chronic obstructive pulmonary disease, and cystic fibrosis. In this review, we explore the multiple functions of AAT, in particular, the anti-inflammatory and serine protease inhibitory functions, and AAT’s therapeutic potential in a variety of human diseases through published literature.

Targeting Dendritic Cells with Alpha 1 Antitrypsin has Therapeutic Potentials in Lupus

Abstract Increasing evidence indicate that dendritic cells (DCs) play a critical role in the development and pathogenesis of systemic lupus erythematosus (SLE). Targeting DCs in lupus may be beneficial, but it has not been yet achieved effectively. Alpha 1 antitrypsin (AAT) is a multifunctional protein with anti-inflammatory activity and immunoregulatory functions. In this study, we tested the effects of AAT on DCs and B cells in vitro and its therapeutic potential in vivo in two spontaneous mouse models of lupus. We demonstrated that AAT treatment significantly inhibited DC maturation, induced from C57BL/6 or B6.Sle1.Sle2.Sle3 lupus-prone mice, (using MHC-II IA, CD80, CD86 and CD40 as markers) and function (IFN-I, IL-1β, TNF-α, and IL-12 secretion) in response to TLR4 and TLR9 stimulation. Interestingly, the inhibitory effect of AAT on DCs inhibited B cell proliferation and antibody production induced in DC – B cell co-cultures. Importantly, in vivo AAT treatment prevented the development of kidney disease in MRL/lpr mice and AAT treatment delivered with an AAV-gene therapy vector extended the life span of NZM2410 mice, with 70% mice that received AAT remaining alive at 72 weeks of age vs. all control animals died by 46 weeks of age. In all studies, AAT treatment significantly reduced lupus-associated autoantibody levels, including anti-dsDNA IgG and anti-nuclear autoantibodies. Considering the well-known safety profile of AAT, our results strongly suggest a therapeutic potential of AAT for the treatment of SLE in humans. This work was supported by grants from University of Florida Research Foundation and Grifols Inc.

Alpha 1-antitrypsin inhibits microglia activation and facilitates the survival of iPSC grafts in hypertension mouse model

This study was conducted to investigate the use of Alpha 1-antitrypsin (AAT) to inhibit microglia activation in chronic hypertension model and provide a permissive environment for stem cell transplantation. Chronic ocular hypertension of C57BL/6 mice using magnetic microbead injection was induced 3 weeks prior to iPSCs transplantation. The ocular hypertension model was assessed histologically and intraocular pressure was measured. Survival of grafted cells and microglia activation were examined by flow cytometry and immunofluorescence in AAT and PBS treated hosts. Retinal cytokines expression was also detected by real-time PCR. Chronic ocular hypertension resulted in persistent microglia activation and stem cell grafts loss. AAT treatment significantly inhibited microglia activation and facilitated the survival of transplant iPSCs 4w post transplantation compared to PBS treatment. AAT holds tremendous potential for the clinical application to control neuroinflammation factor in glaucoma and improve the stem cell replacement therapy of retinal neurodegenerative disease.

Epidemiology, Diagnosis and Available Treatment for Alpha 1 Antitrypsin Deficiency-related Emphysema in Europe

Alpha 1 antitrypsin (AAT) deficiency (AATD) is a rare genetic risk factor that predisposes an individual to develop early-onset emphysema. While accurate diagnosis of severe AATD is an important goal of clinical care, a minority of individuals with AATD are diagnosed and lack of awareness about the disease is the major suspected cause for this. Since the 1980s, therapy with human plasma-derived AAT has been the only specific treatment for AATD aiming to slow emphysema progression. The first randomised controlled trial to demonstrate this slowing of disease progression with AAT was the Randomized, placebo-controlled trial of augmentation therapy in Alpha1 Proteinase Inhibitor Deficiency (RAPID) study. The RAPID programme, consisting of the initial trial plus its open-label extension (OLE), is the largest completed clinical study of AAT therapy in AATD and the only trial designed specifically to explore the disease-modifying effect of AAT treatment. The RAPID-OLE data substantiate those of the RAPID trial, establishing the sustained efficacy and good tolerability for AAT treatment, providing evidence that AAT treatment modifies the disease course, and supporting the importance of early intervention.

Alpha 1-antitrypsin ameliorates ventilator-induced lung injury in rats by inhibiting inflammatory responses and apoptosis.

Mechanical ventilation is extensively used to treat patients with lung injury but may result in ventilator-induced lung injury (VILI). The present study investigated the protective effect of alpha 1-antitrypsin (AAT) on VILI. Adult male rats were subjected to sham, ventilation + saline, or ventilation + AAT treatment and lung injuries were evaluated. Peripheral blood and bronchoalveolar lavage fluid (BALF) were obtained to assess systemic and local inflammatory responses, respectively. Mechanical ventilation resulted in lung injury, as evidenced by histological abnormalities as well as elevations in PaO2/FiO2 ratio, the wet-to-dry weight ratio, and the BALF level of proteins. The intravenous administration of AAT significantly improved these parameters of lung function, suggesting a protective role of AAT in VILI. Mechanistically, ventilator-induced inflammation was effectively reduced by AAT, as evidenced by decreases in BALF neutrophil counts, BALF cytokines, and serum adhesion factors. In contrast, anti-inflammatory interleukin-10 in BALF was increased in response to AAT. AAT treatment also inhibited the expression of nuclear factor-κB, Bax, and cleaved caspase-3 while promoting Bcl-2 expression in ventilator-injured lung tissues. AAT treatment can ameliorate VILI by inhibiting inflammatory mediator production and apoptosis. Impact statement Mechanical ventilation has been commonly used to treat patients with lung injury but may result in ventilator-induced lung injury (VILI). Few effective treatment options are currently available to reduce VILI. Alpha 1-antitrypsin (AAT) is an inhibitor of serine protease with anti-inflammatory and antiapoptotic properties, suggesting a possible role in attenuating lung injury. The present study demonstrates that AAT inhibits the development of VILI by modulating inflammation- and apoptosis-related protein expression. Therefore, AAT may be a novel therapeutic agent for acute respiratory distress syndrome patients undergoing mechanical ventilation.

Alpha-1 antitrypsin supplementation improves alveolar macrophages efferocytosis and phagocytosis following cigarette smoke exposure.

Cigarette smoking (CS), the main risk factor for COPD (chronic obstructive pulmonary disease) in developed countries, decreases alveolar macrophages (AM) clearance of both apoptotic cells and bacterial pathogens. This global deficit of AM engulfment may explain why active smokers have worse outcomes of COPD exacerbations, episodes characterized by airway infection and inflammation that carry high morbidity and healthcare cost. When administered as intravenous supplementation, the acute phase-reactant alpha-1 antitrypsin (A1AT) reduces the severity of COPD exacerbations in A1AT deficient (AATD) individuals and of bacterial pneumonia in murine models, but the effect of A1AT on AM scavenging functions has not been reported. Apoptotic cell clearance (efferocytosis) was measured in human AM isolated from patients with COPD, in primary rat AM or differentiated monocytes exposed to CS ex vivo, and in AM recovered from mice exposed to CS. A1AT (100 μg/mL, 16 h) significantly ameliorated efferocytosis (by ~50%) in AM of active smokers or AM exposed ex vivo to CS. A1AT significantly improved AM global engulfment, including phagocytosis, even when cells were simultaneously challenged with apoptotic and Fc-coated (bacteria-like) targets. The improved efferocytosis in A1AT-treated macrophages was associated with inhibition of tumor necrosis factor-α converting enzyme (TACE) activity, decreased mannose receptor shedding, and markedly increased abundance of efferocytosis receptors (mannose- and phosphatidyl serine receptors and the scavenger receptor B2) on AM plasma membrane. Directed airway A1AT treatment (via inhalation of a nebulized solution) restored in situ airway AM efferocytosis after CS exposure in mice. The amelioration of CS-exposed AM global engulfment may render A1AT as a potential therapy for COPD exacerbations.

84. Alpha 1 Antitrypsin Protein & Gene Therapies for the Treatment of Lupus in Animal Models

Systemic lupus erythematosus (SLE) is an autoimmune rheumatic disorder. Although the pathogenesis of SLE remains elusive, over-reactive dendritic cells (DCs), which promote B cell activation and autoantibodies secretion, play critical roles in the disease development. Alpha-1 antitrypsin (AAT) is a multifunctional protein with anti-inflammatory, cytoprotective and immunoregulatory properties. We has shown that AAT has protective effect in autoimmune disease models including type 1 diabetes and rheumatoid arthritis. In this study, we tested therapeutic potentials of AAT in controlling DC and B cells function and the development of SLE in a spontaneous lupus mouse model. Using bone marrow cells from normal (C57BL/6) and lupus prone (B6. TC, MRL/lpr) mice, we showed that AAT treatment significantly inhibited lipopolysaccharide (LPS) (TLR4 agonist) or CpG (TLR9 agonist) induced DC (cDC and pDC) maturation. In this in vitro system, AAT significantly inhibited the production of IFN-I, IL-1β, IL-6 and TNF-α from DCs. AAT treated DC also have significantly lower potential in stimulating B cell proliferation and functions. Based on these results, performed following experiments using spontaneous lupus mouse models. In order to test this therapeutic potential, we treated female MRL/lpr mice (at 7-weeks of age, n=10) with clinical grade of AAT (2 mg/mouse, every 3 days) or PBS for 11 weeks. Consistent with our in vitro observations, results from this experiment showed that AAT treatment significantly inhibited DC maturation and reduced DC susceptibility to LPS stimulation. Importantly, AAT treatment significantly lowered serum antibody (anti-dsDNA IgG and anti-nuclear antibodies, ANAs) levels and urine albumin levels. Detailed pathological examinations showed that AAT treatment prevented kidney disease development. To confirm this observations and test the long-term effect of AAT treatment, we performed second experiment using both AAT protein and gene therapies. In this experiment, we treated adult female NZM2410 (another commonly used spontaneous lupus model) mice with AAT protein and rAAV8-CB-AAT vector (1×1011 vg/mouse, single IP injection). While 100% mice in control group develop lupus and died at 46 week of age, 50% mice in AAT protein treatment group remain lupus free at 55 weeks of age. Intriguingly, AAT gene therapy (rAAV8-CB-AAT) significantly prevent lupus development (70% mice remain lupus free at 63 weeks of age, P=0.0059). These results clearly demonstrated the therapeutic effect of AAT protein and gene therapy in lupus mouse model. Our results also indicated the advantage of rAAV8 mediated gene therapy for the chronic autoimmune diseases. In summary, we showed AAT inhibited the activation and function of DCs and B cells in vitro and in vivo. We also showed AAT treatment (protein therapy and gene therapy) prevent lupus development in spontaneous lupus mouse models. Considering the safety profile of AAT and rAAV, our results may be translated into clinical application and lead to a novel (safe and effective) therapy for SLE in humans. This work was supported by grants from University of Florida and Grifols, Inc.

Alpha-1 antitrypsin therapy is safe and well tolerated in children and adolescents with recent onset type 1 diabetes mellitus.

Alpha-1 antitrypsin (AAT) has been shown to reduce pro-inflammatory markers and protect pancreatic islets from autoimmune responses in recent studies. Our aim was to evaluate its safety and tolerability in three different doses, in a pediatric population with recent onset type 1 diabetes mellitus (T1DM). A 37-wk prospective, open-label, phase I/II interventional trial, comprised of 24 recently diagnosed subjects (12 males; age 12.9 ± 2.4 yr), who received 18 infusions of 40, 60, or 80 mg/kg/dose high-purity, liquid, ready to use AAT over 28 wk (Glassia(®) ; Kamada Ltd., Ness Ziona, Israel). safety and tolerability; secondary outcomes: glycemic control, C-peptide reserve, and autoantibody levels. Possible responders were defined as individuals with peak C-peptide that declined less than 7.5% below baseline. No serious adverse events, diabetic ketoacidosis (DKA), or severe hypoglycemic episodes were reported. Adverse events were dose-independent and transient. Glycemic control parameters improved during the study in all groups, independent of dosage. Hemoglobin A1c (HbA1c) decreased from 8.43 to 7.09% (mean, p < 0.001). At the end of the study, 18 subjects (75%) had a peak C-peptide ≥0.2 pmol/mL. Eight subjects (33.3%) were considered possible responders and were characterized by shorter duration of T1DM at screening (54.5 ± 34.3 vs. 95.9 ± 45.7 d, p = 0.036) and greater decrease in their HbA1c during the study period (-2.94 ± 1.55 vs.-0.95 ± 1.83%, p = 0.016). AAT treatment was safe and well tolerated in pediatric subjects with recently diagnosed autoimmune diabetes. Placebo-controlled studies with larger cohorts and dose range are warranted in order to assess efficacy in maintaining pancreatic beta cell reserve and glycemic control.

α1 Anti-Trypsin (AAT) Mitigates Hematopoietic Injury and Enhances Bone Marrow Recovery After Total Body Irradiation (TBI)

Abstract 4142 Background:Injury to healthy (non-target) tissues still is a major limitation of radiation therapy, at least in part related to release of cytokines, including TNFα and IL-1β, which amplify tissue damage. Cytokine release is particularly prominent in patients who receive total body irradiation (TBI) before hematopoietic cell transplantation (HCT), as interactions of allogeneic donor cells with patient tissue contribute to the resulting “cytokine storm” and the development of graft versus-host-disease (GVHD). In murine models, administration of alpha-1 anti-trypsin (AAT) in the peri-transplant period decreased GVHD incidence and mortality. AAT, a member of the serine protease inhibitor (serpin) family, is a major protective protein in the circulation and has been used successfully in the clinic for other indications. Methods:We were interested in determining the potential benefits of AAT in preventing toxicity related to the transplant conditioning regimen, specifically TBI. AAT inhibits proteinase-3 (PR3) which, among other targets, cleaves IL-32 thereby leading to activation of TNFa and enhancing the cytokine storm. Since others have also suggested that AAT, via enhanced expression of heme oxygenase-1 (HMOX-1), leads to activation of Nrf2, thereby enhancing transcription of anti-inflammatory cytokines such as IL10 and the IL-1 receptor antagonist (IL1Ra), we determined the overall shift in the cytokine milieu and cell death. Thus, we irradiated male C3H/HeN mice (n = 5 mice per group; 6–8 weeks old) with sub-lethal doses (500, 600 and 700 cGy) of TBI from a 137Cs source. AAT (300 μg/animal) was administered intra-peritoneally 1 hour before and every 48 hours after TBI for a total of 6 doses. The effect of TBI/AAT on hematopoiesis was analyzed by growing granulocyte-macrophage colony forming units (GM-CFU) from bone marrow cells, on days 3, 7 and 14 after TBI. Results:Results were compared to those with cells from albumin-treated controls. Marrows (days 3 and 7) from AAT-treated mice generated higher GM-CFU counts than those from controls (mean = 25 vs. 5 colonies per 25 × 103 cells plated after 500cGy, and 15 vs. 3 colonies per 25 × 103 cells after 600 cGy). Peripheral blood and unsorted bone marrow from AAT-treated mice showed up-regulation of HMOX-1 and Nrf2 (30 and 50 log2 increase, respectively), and enhanced transcription of IL-10 and IL-1Ra (50 and 10 log2, respectively) compared to albumin treated donors. PR3 and TNFα, in contrast, were down-regulated (5 log2 and 7 log2 decrease in comparison to albumin treated controls).The cytokine mitigating effects of AAT were accompanied by attenuation of ATM-p53-dependent DNA damage responses in bone marrow cells (determined on days 3, 7, and 14), showing a 3-fold decrease in p53 protein levels, and a 6-fold decrease in phospho-ATM in comparison to albumin treated controls (peak day 7). In addition, protein levels of caspase 3 and caspase 9 were decreased (2-fold and 5-fold, respectively; peak on day 7) in unsorted marrow cells and spleen lysates of AAT treated mice in comparison to albumin treated controls. Bone marrow histopathology revealed normo-cellularity and a decrease in cleaved caspase 3 staining in AAT-treated mice compared to albumin treated animals. Summary and conclusions:AAT treatment significantly mitigated the hematopoietic toxicity induced by sub-lethal TBI. The mechanism involves cytokine suppression, associated with attenuation of ATM-p53 mediated DNA damage response. Taken together, these data suggest that AAT treatment pre-TBI provides protection against radiation injury. Disclosures:No relevant conflicts of interest to declare.

Alpha 1-antitrypsin reduces inflammation and enhances mouse pancreatic islet transplant survival

The promise of islet cell transplantation cannot be fully realized in the absence of improvements in engraftment of resilient islets. The marginal mass of islets surviving the serial peritransplant insults may lead to exhaustion and thereby contribute to an unacceptably high rate of intermediate and long-term graft loss. Hence, we have studied the effects of treatment with alpha 1-antitrypsin (AAT) in a syngeneic nonautoimmune islet graft model. A marginal number of syngeneic mouse islets were transplanted into nonautoimmune diabetic hosts and islet function was analyzed in control and AAT treated hosts. In untreated controls, marginal mass islet transplants did not restore euglycemia. Outcomes were dramatically improved by short-term AAT treatment. Transcriptional profiling identified 1,184 differentially expressed transcripts in AAT-treated hosts at 3 d posttransplantation. Systems-biology-based analysis revealed AAT down-regulated regulatory hubs formed by inflammation-related molecules (e.g., TNF-α, NF-κB). The conclusions yielded by the systems-biology analysis were rigorously confirmed by QRT-PCR and immunohistology. These data suggest that short-term AAT treatment of human islet transplant recipients may be worthy of a clinical trial.

Alpha‐1 antitrypsin reduces ovariectomy‐induced bone loss in mice

Bone loss occurs in menopause due to the decreased estrogen and increased proinflammatory cytokine production. Alpha‐ 1antitrypsin (AAT) is a multifunctional protein with proteinase inhibitor and anti‐inflammatory activities. To determine whether AAT mitigates bone loss induced by estrogen deficiency, thirty‐eight female C57BL/6J mice (7‐wk‐old), were either ovariectomized or sham‐operated. Ovariectomized animals were randomly assigned to AAT‐injected (n=13; 2 mg/mouse, every 3 days for 30 days) or phosphate buffered saline (PBS)‐injected group (n=12), while sham‐operated mice (Sham; n=13) were injected with PBS and used as controls. Ovariectomy resulted in decreased wet uterus weight (P&lt;0.01), bone loss, increased serum leptin concentrations, and higher body weight (P&lt;0.01) compared to sham. AAT treatment increased tibial trabecular bone volume/total volume and trabecular thickness relative to PBS treatment in ovariectomized mice (P&lt;0.01). Ovariectomized mice with AAT‐injection had higher uterus weight (P&lt;0.01), lower serum osteocalcin levels (P&lt;0.05), fewer bone marrow TRAP‐positive osteoclasts (P&lt;0.05) and less expression of calcitonin receptor (P&lt;0.01) in bone than mice injected PBS. These data demonstrate that AAT reduces ovariectomy‐induced bone loss in mice possibly through inhibiting osteoclast activity and bone resorption.

Alpha‐1 antitrypsin reduces ovariectomy‐induced bone loss in mice

Proinflammatory cytokines are primary mediators of bone loss in estrogen deficiency. This study determined whether alpha-1 antitrypsin (AAT), a multifunctional protein with proteinase inhibitor and anti-inflammatory activities, mitigates bone loss induced by estrogen deficiency. Mice were either sham-operated or ovariectomized and injected with either AAT or phosphate buffered saline (PBS). Ovariectomy resulted in decreased wet uterus weight, significant bone loss, increased serum leptin concentrations, and higher body weight compared to sham. AAT injection increased tibial trabecular bone volume/total volume and trabecular thickness compared to PBS injection in ovariectomized mice. Ovariectomized mice with AAT treatment had higher uterus weight, lower serum osteocalcin levels, fewer bone marrow tartrate-resistant acid phosphatase-positive osteoclasts, and less expression of calcitonin receptor in bone than that in PBS-injected mice. These data demonstrate that AAT mitigates ovariectomy-induced bone loss in mice possibly through inhibiting osteoclast activity and bone resorption.