Search Results (142)

Objectives: Previous studies have suggested differences in vasculitic and eosinophilic phenotypes based on anti-neutrophil cytoplasmic antibody (ANCA) positivity in eosinophilic granulomatosis with polyangiitis (EGPA). However, their relevance under the 2022 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) classification criteria remains unclear. We aimed to evaluate the clinical features and outcomes of EGPA according to myeloperoxidase (MPO)-ANCA status in a Korean cohort. Methods: We conducted a retrospective cohort study that included 57 patients with EGPA without proteinase 3-ANCA positivity who fulfilled the 2022 ACR/EULAR classification criteria. Patients were classified into MPO-ANCA-positive (n = 25) and MPO-ANCA-negative (n = 32) groups. Clinical manifestations, laboratory findings, and outcomes, including all-cause mortality, relapse, end-stage kidney disease (ESKD), cerebrovascular accident (CVA), and acute coronary syndrome (ACS), were compared between the two groups. Results: MPO-ANCA-positive patients exhibited higher Five-Factor Scores (1.0 [0.0–1.0] vs. 0.0 [0.0–1.0], p = 0.038), lower Short Form 36 Physical Component Summary scores (35.0 [19.7–56.3] vs. 52.5 [43.5–69.7], p = 0.048), and elevated systemic inflammation markers (higher erythrocyte sedimentation rate: 58.0 [16.0–97.5] mm/hr vs. 25.5 [7.0–63.8] mm/hr, p = 0.026). Constitutional symptoms were more frequent among MPO-ANCA-positive patients (n = 14 [56.0%] vs. n = 3 [9.4%], p < 0.001), whereas no significant differences were found in vasculitic or eosinophilic manifestations. Kaplan–Meier analysis revealed no differences in the overall (p = 0.36), relapse-free (p = 0.80), ESKD-free (p = 0.87), CVA-free (p = 0.26), or ACS-free (p = 0.94) survival rates between the two groups. Conclusions: In Korean patients with EGPA classified under the 2022 ACR/EULAR classification criteria, MPO-ANCA positivity, as compared to ANCA-negative status, was associated with a higher disease burden and poorer quality of life but not with distinct vasculitic or eosinophilic manifestations and adverse outcomes. Full article

Background: Anti-PAR 1 (protease-activated receptor 1) and anti-ACE 2 (angiotensin 2-converting enzyme 2) antibodies are a kind of non-HLA (human leukocyte antigens) antibodies postulated to be of significance in autoimmunological diseases and organ transplantation. Methods: We assessed anti-PAR 1 and anti-ACE 2 antibody levels in patients with membranous nephropathy n= 18, focal and segmental glomerulosclerosis (FSGS) n = 25, lupus nephritis (LN) n = 17, IgA nephropathy n = 14, mesangial proliferative (non-IgA) glomerulonephritis n = 6, c-ANCA (cytoplasmic anti-neutrophil cytoplasmic antibodies) vasculitis n = 40, p (perinuclear)-ANCA vasculitis n = 16, and compared them with a healthy control group n = 22. Next, we observed the clinical course of the patients (creatinine, total protein, and albumin) up to 2 years and correlated the results with the level of antibodies. Results: The anti-PAR 1 antibody level was lower in membranous nephropathy and FSGS compared to the control group. Anti-PAR 1 antibody levels were higher in secondary compared to primary glomerulonephritis. Both anti-PAR 1 and anti-ACE 2 antibody levels correlated positively (in focal and segmental glomerulosclerosis) or negatively (in lupus nephritis) with total protein and albumin at different time points of observation. Anti-PAR 1 and anti-ACE 2 antibody levels correlated also with creatinine level at one time point of observation in IgA nephropathy. Anti-PAR 1 and anti-ACE 2 antibodies correlated with each other in membranous nephropathy, FSGS, and p- and c-ANCA vasculitis (p < 0.05). Conclusions: The anti-PAR 1 antibody level was lower in membranous nephropathy and focal and segmental glomerulosclerosis compared to the control group. Anti-PAR 1 antibody levels tend to be higher in secondary compared to primary glomerulonephritis. Full article

Flavonoids, like Hesperetin, have been shown to be an ACE2 receptor agonists with antioxidant and pro-apoptotic activity and can induce apoptosis in cancer cells. ACE2 receptors are abundant in lung cancer cells. Here, we explored the application of Hesperetin bound to PegPLGA-coated nanoparticles (Hesperetin nanoparticles, HNPs) and anti-CD40 antibody as an aerosol treatment for lung tumor-bearing mice. The Hesperetin nanoparticles (HNPs) were engineered using a nano-formulation microfluidic technique and polymeric nanoparticles. The in vitro studies were performed in human A549 (ATCC) and murine LL/2-Luc2 (ATCC) lung cancer cell lines. A syngeneic orthotopic murine model of lung cancer was generated in wild (+/+) C57/BL6 background mice with luciferase-positive cell line LL/2-Luc2 cells. Lung tumor-bearing mice were treated via aerosol inhalation with HNP, anti-CD40 antibody, or both. Survival was used to analyze the efficacy of the aerosol treatment. The cohorts were also analyzed for body condition score, weight, and liver and kidney function. Analysis of an orthotopic murine lung cancer model demonstrated a differential uptake of the HNPs and anti-CD40 by the cancer cells. A higher survival rate was observed when the combination of aerosol treatment with HNPs was added with the treatment with anti-CD40 (p < 0.001), as compared to anti-CD40 alone (p < 0.01). Moreover, two tumor-bearing mice survived long-term with the combination treatment, and their tumors were diminished. Subsequently, these two mice were shown to be refractory to the development of subcutaneous tumors, indicating systemic resilience to developing new tumors. Using an inhalation-based administration, we successfully established a treatment model of increased therapeutic efficacy with HNPs and anti-CD40 in an orthotopic murine lung cancer model. Our findings open the possibility of improved lung cancer treatment using nanoparticles like flavonoids and immunoadjuvants. Full article

Background: Oxidative stress, inflammation, and endothelial dysfunction are important processes in the progression of atherosclerosis and the occurrence of acute coronary syndromes (ACSs). Omega-3 polyunsaturated fatty acids (Omega-3 PUFAs) are present in marine organisms and have the capacity to reduce all these processes and, at the same time, the progression of atherosclerosis and the emergence of ACSs. Aim: To evaluate the role of Omega-3 PUFAs therapy on parameters of oxidative stress, inflammatory syndrome, endothelial dysfunction, and long-term prognosis in acute coronary syndromes. Methods: One thousand one hundred forty patients were admitted to Clinic County Emergency Hospital Brasov with ACS and were enrolled in a prospective study. The study was divided into four groups related to the type of ACS and treatment with Omega-3 PUFAs added to the optimal medical therapy (OMT). The effect of Omega-3 PUFAs therapy associated with the OMT was determined by measuring the dynamics of the following parameters: (a) oxidative stress—total antioxidant status (TAS), oxidated low density lipoprotein cholesterol antibodies (Ab anti-ox-LDL), IgG anti-Myeloperoxidase antibodies (IgG type Ab anti-MPO); (b) inflammatory syndrome—C-reactive protein and fibrinogen; (c) endothelial dysfunction—flow mediated dilation (FMD) and von Willebrand factor (vWf) activity, from baseline to 6 months of follow-up. Clinical events followed at 5 years were cardiovascular and sudden death, Non-ST and ST segment elevation ACS, in stent thrombosis and restenosis, stroke, readmission in hospital for ACS and for heart failure. Results: In ACS groups, treatment with Omega-3 PUFAs added to the OMT significantly decreased the parameters of oxidative stress, inflammatory syndrome, and endothelial dysfunction at 6 months of follow-up. Regarding the clinical events, a significant reduction in the risk of cardiovascular and sudden death and a decreased incidence of Non-ST and ST segment elevation ACS, in-stent restenosis, readmission for ACS and heart failure, was observed in Omega-3 PUFA-treated groups in comparison to control groups. Conclusions: In acute coronary syndromes, therapy with Omega-3 PUFAs added to the OMT resulted in a significant decrease of parameters of oxidative stress, inflammation, and endothelial dysfunction at 6 months and also a significant improvement in the long-term prognosis. Full article

Background/Objectives: Novel mRNA vaccines have been successfully utilized to curtail the SARS-CoV-2 pandemic. However, the immunology underlying CoV2 vaccinations, particularly with repeated boosting, has not been properly characterized due to limitations in the preclinical modeling of SARS-CoV-2 infection/vaccinations as well as constantly changing vaccine formulations. The immunoregulatory aspects involved in such vaccine approaches remain unclear. Antibodies, due to inherent immunogenicity by VDJ gene rearrangement, have the potential to induce antibodies directed towards them called anti-idiotype antibodies, which can play a downregulatory role in responses. The paratope of some of these anti-idiotype antibodies can also act as a mirror to the original antigen, which, in the case of SARS-CoV-2 vaccines, would be to the spike protein and, therefore, also be capable of binding its target, ACE2, potentially causing adverse effects. Methods: To investigate if sequential SARS-CoV-2 mRNA vaccination can induce anti-idiotype antibody responses, K18 hACE2 transgenic mice were serially vaccinated with a SARS-CoV-2 mRNA construct to determine the kinetics of anti-spike and anti-ACE2 responses via custom-made ELISAs. Results: While sequential vaccination produced robust anti-spike responses, anti-ACE2 levels were also detected and gradually amplified with each boost. These anti-ACE2 antibodies persisted for 3 months after the final vaccination and showed evidence of hACE2 binding, as levels were lower in K18 mice in comparison to the wild type. Conclusions: These data would suggest that sequential SARS-CoV-2 mRNA vaccination has the potential to induce anti-ACE2 antibodies in mice, with each boost amplifying the amount of antibody. Full article

Background/Objectives: Premature ovarian insufficiency (POI) is a disorder that affects women under the age of 40. It is characterized by decreased ovarian function, elevated gonadotropin levels, and decreased estradiol. SARS-CoV-2 disrupts ovarian function largely through oxidative stress, inflammation, and immunological dysregulation, which are enhanced by its entrance into ovarian tissues via ACE2 receptors. The purpose of this comprehensive review was to investigate the molecular pathways that link SARS-CoV-2 infection to POI and analyze their consequences for ovarian reserve and fertility. Methods: We searched databases such as PubMed, Scopus, EMBASE, and Google Scholar for papers published between 2020 and 2024. Eligible studies investigated the effects of SARS-CoV-2 on ovarian function, including the hormonal indicators anti-Müllerian hormone (AMH) and follicle-stimulating hormone (FSH), oocyte quality, and ovarian reserve. The data were compiled into a complete examination of molecules and clinical findings. Increased inflammatory indicators, such as interleukin-6 and NLRP3 inflammasome activation, impaired ovarian homeostasis. Anti-SARS-CoV-2 antibodies in follicular fluid could have impaired oocyte quality. Observational studies showed transitory decreases in AMH and changed FSH levels following infection, with variable effects on antral follicle count and IVF results. Changes in lipid profiles and VEGF expression emphasized the virus’s influence on ovarian angiogenesis and the ovarian microenvironment. Conclusions: SARS-CoV-2 infection impairs ovarian function by causing oxidative stress, inflammation, and hormonal disruption, thereby increasing the incidence of POI. While most alterations are temporary, the long-term reproductive consequences remain unknown. Continuous monitoring and specific treatments are required to reduce the reproductive risks associated with COVID-19. Full article

The first infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes the coronavirus disease 2019 (COVID-19), occurred in December 2019. Within a single month, the disease reached other countries, spreading in a rapid and generalized manner worldwide to cause the COVID-19 pandemic. In Brazil, the number of COVID-19 cases surpassed 38 million. This study was conducted to produce antibodies against SARS-CoV-2 and investigate the immunogenic potential of synthetic peptides containing partial sequences of the main proteins (spike, membrane, and nucleocapsid proteins). In addition, we evaluated the ability of the antibodies to impair the interaction between the spike S1 protein and human ACE-2 protein, which is the main route of entry of the virus into host cells. By immunizing horses with synthetic peptides, we obtained hyperimmune sera with specific anti-SARS-CoV-2 antibodies, which were fragmented to release the F(ab’)2 portion that binds to the different SARS-CoV-2 proteins as a recombinant S1-protein and proteins from a viral lysate. The other F(ab’)2 samples also impaired the interaction between S1 protein and ACE-2 proteins, showing high potential to prevent viral spreading. Full article

Background/Objectives: While post-acute COVID-19 syndrome is well known and extensively studied, the post-acute COVID vaccination syndrome (PACVS) is a more recent nosological entity that is poorly defined at the immunopathological level, although it shares many symptoms with the sequelae of viral infections. Methods: This single-center retrospective study reports a case series of 17 subjects vaccinated with mRNA or adenoviral vector vaccines who were healthy before vaccination and had never been infected with SARS-CoV-2 but who presented with symptoms similar to PACVS for a median time of 20 months (min 4, max 32). The medical records of all patients referred to our outpatient clinic over a one-year period were retrospectively analyzed. Results: In this group, serological tests showed that, in addition to positivity for anti-spike protein antibodies, a high percentage of subjects were positive for antibodies against G protein-coupled receptors and molecules involved in the response to SARS-CoV-2. In a panel of 16 autoantibodies tested, a few were positively associated with some of the symptoms reported by patients: anti-ATR1 with lymphadenopathy and/or tonsillitis; anti-ACE2 with skin symptoms such as ecchymosis, skin oedema, and rash; anti-MAS1 with widespread burning sensation; and anti-STAB1 with skin oedema and rash. Anti-ADRA2A were negatively associated with memory loss and/or mental fog. ACE2 correlated with the serum levels of anti-S antibodies, supporting the hypothesis of an anti-idiotype mechanism in the immunopathogenesis of PACVS. Conclusions: This exploratory analysis suggests that the levels of autoantibodies directed against ACE2, and probably also MAS1 and STAB1, may serve as biomarkers for PACVS. Full article

The extremely rapid development of understanding and technology that led to the containment of the COVID-19 pandemic resulted from collaborative efforts in the fields of Betacoronavirus pandemicum (SARS-CoV-2) biology, pharmacology, vaccinology, and medicine. Perhaps surprisingly, much of the research was conducted using simple and efficient yeast models. In this manuscript, we describe how yeast, eukaryotic microorganisms, have been used to research this global challenge, focusing on the therapeutic potential of the studies discussed herein. Thus, we outline the role of yeast in studying viral protein interactions with the host cell proteome, including the binding of the SARS-CoV-2 virus spike protein to the human ACE2 receptor and its modulation. The production and exploration of viral antigens in yeast systems, which led to the development of two approved COVID-19 vaccines, are also detailed. Moreover, yeast platforms facilitating the discovery and production of single-domain antibodies (nanobodies) against SARS-CoV-2 are described. Methods guiding modern and efficient drug discovery are explained at length. In particular, we focus on studies designed to search for inhibitors of the main protease (Mpro), a unique target for anti-coronaviral therapies. We highlight the adaptability of the techniques used, providing opportunities for rapid modification and implementation alongside the evolution of the SARS-CoV-2 virus. Approaches introduced in yeast systems that may have universal potential application in studies of emerging viral diseases are also described. Full article

The action of mRNA-based vaccines requires the expression of the antigen in cells targeted by lipid nanoparticle–mRNA complexes. When the vaccine antigen is not fully retained by the producer cells, its local and systemic diffusion can have consequences depending on both the levels of antigen expression and its biological activity. A peculiarity of mRNA-based COVID-19 vaccines is the extraordinarily high amounts of the Spike antigen expressed by the target cells. In addition, vaccine Spike can be shed and bind to ACE-2 cell receptors, thereby inducing responses of pathogenetic significance including the release of soluble factors which, in turn, can dysregulate key immunologic processes. Moreover, the circulatory immune responses triggered by the vaccine Spike is quite powerful, and can lead to effective anti-Spike antibody cross-binding, as well as to the emergence of both auto- and anti-idiotype antibodies. In this paper, the immunologic downsides of the strong efficiency of the translation of the mRNA associated with COVID-19 vaccines are discussed together with the arguments supporting the idea that most of them can be avoided with the advent of next-generation, mucosal COVID-19 vaccines. Full article

Background: Long-lived, re-activatable immunity to SARS-CoV-2 and its emerging variants will rely on T cells recognizing conserved regions of viral proteins across strains. Heterologous prime–boost regimens can elicit elevated levels of circulating CD8+ T cells that provide a reservoir of first responders upon viral infection. Although most vaccines are currently delivered intramuscularly (IM), the initial site of infection is the nasal cavity. Methods: Here, we tested the hypothesis that a heterologous prime and boost vaccine regimen delivered intranasally (IN) will generate improved immune responses locally at the site of virus infection compared to intramuscular vaccine/booster regimens. Results: In a transgenic human ACE2 murine model, both a Spike-expressing single-cycle adenovirus (SC-Ad) and an IFNß safety-enhanced replication-competent Vesicular Stomatitis Virus (VSV) platform generated anti-Spike antibody and T-cell responses that diminished with age. Although SC-Ad-Spike boosted a prime with VSV-Spike-mIFNß, SC-Ad-Spike alone induced maximal levels of IgG, IgA, and CD8+ T-cell responses. Conclusions: There were significant differences in T-cell responses in spleens compared to lungs, and the intranasal boost was significantly superior to the intramuscular boost in generating sentinel immune effectors at the site of the virus encounter in the lungs. These data show that serious consideration should be given to intranasal boosting with anti-SARS-CoV-2 vaccines. Full article

Background/Objectives: Pancreatic cancer is the third leading cause of death related to cancer. The only possible cure presently is complete surgical resection; however, this is limited by difficulty in clearly defining tumor margins. Enhancement of the visualization of pancreatic ductal adenocarcinoma (PDAC) tumor margins using near-infrared dye-conjugated tumor-specific antibodies was pioneered by using anti-CEA, anti-CA19.9, and anti-MUC5AC in orthotopic mouse models of pancreatic cancer. Recently, an antibody to Mucin 4 (MUC4) conjugated to a fluorescent probe has shown promise in targeting colon tumors in orthotopic mouse models. Methods: In the present study, we targeted pancreatic cancer using an anti-MUC4 antibody conjugated to IRDye800 (anti-MUC4-IR800) in orthotopic mouse models. Two pancreatic cancer human cell lines were used, SW1990 and CD18/HPAF. Results: Anti-MUC4-IR800 targeted the two pancreatic cancer cell line tumors in orthotopic mouse models with high tumor-to-pancreas ratios and high tumor-to-liver ratios, with greater targeting seen in SW1990. Conclusions: The present results suggest anti-MUC4-IR800’s potential to be used in fluorescence-guided surgical resection of pancreatic cancer. Full article

The interaction of the SARS-CoV-2 spike protein with membrane-bound angiotensin-converting enzyme-2 (ACE-2) receptors in epithelial cells facilitates viral entry into human cells. Despite this, ACE-2 exerts significant protective effects against coronaviruses by neutralizing viruses in circulation and mitigating inflammation. While SARS-CoV-2 reduces ACE-2 expression, vitamin D increases it, counteracting the virus’s harmful effects. Vitamin D’s beneficial actions are mediated through complex molecular mechanisms involving innate and adaptive immune systems. Meanwhile, vitamin D status [25(OH)D concentration] is inversely correlated with severity, complications, and mortality rates from COVID-19. This study explores mechanisms through which vitamin D inhibits SARS-CoV-2 replication, including the suppression of transcription enzymes, reduced inflammation and oxidative stress, and increased expression of neutralizing antibodies and antimicrobial peptides. Both hypovitaminosis D and SARS-CoV-2 elevate renin levels, the rate-limiting step in the renin-angiotensin-aldosterone system (RAS); it increases ACE-1 but reduces ACE-2 expression. This imbalance leads to elevated levels of the pro-inflammatory, pro-coagulatory, and vasoconstricting peptide angiotensin-II (Ang-II), leading to widespread inflammation. It also causes increased membrane permeability, allowing fluid and viruses to infiltrate soft tissues, lungs, and the vascular system. In contrast, sufficient vitamin D levels suppress renin expression, reducing RAS activity, lowering ACE-1, and increasing ACE-2 levels. ACE-2 cleaves Ang-II to generate Ang_(1–7), a vasodilatory, anti-inflammatory, and anti-thrombotic peptide that mitigates oxidative stress and counteracts the harmful effects of SARS-CoV-2. Excess ACE-2 molecules spill into the bloodstream as soluble receptors, neutralizing and facilitating the destruction of the virus. These combined mechanisms reduce viral replication, load, and spread. Hence, vitamin D facilitates rapid recovery and minimizes transmission to others. Overall, vitamin D enhances the immune response and counteracts the pathological effects of SARS-CoV-2. Additionally, data suggests that widely used anti-hypertensive agents—angiotensin receptor blockers and ACE inhibitors—may lessen the adverse impacts of SARS-CoV-2, although they are less potent than vitamin D. Full article

Acute adverse reactions to COVID-19 mRNA vaccines are a major concern, as autopsy reports indicate that deaths most commonly occur on the same day of or one day following vaccination. These acute reactions may be due to cytokine storms triggered by lipid nanoparticles (LNPs) and anaphylaxis induced by polyethene glycol (PEG), both of which are vital constituents of the mRNA-LNP vaccines. Kounis syndrome, in which anaphylaxis triggers acute coronary syndrome (ACS), may also be responsible for these cardiovascular events. Furthermore, COVID-19 mRNA-LNP vaccines encompass adjuvants, such as LNPs, which trigger inflammatory cytokines, including interleukin (IL)-1β and IL-6. These vaccines also produce spike proteins which facilitate the release of inflammatory cytokines. Apart from this, histamine released from mast cells during allergic reactions plays a critical role in IL-6 secretion, which intensifies inflammatory responses. In light of these events, early reduction of IL-1β and IL-6 is imperative for managing post-vaccine cytokine storms, ACS, and myocarditis. Corticosteroids can restrict inflammatory cytokines and mitigate allergic responses, while colchicine, known for its IL-1β-reducing capabilities, could also prove effective. The anti-IL-6 antibody tocilizumab also displays promising treatment of cytokine release syndrome. Aside from its significance for treating anaphylaxis, epinephrine can induce coronary artery spasms and myocardial ischemia in Kounis syndrome, making accurate diagnosis essential. The upcoming self-amplifying COVID-19 mRNA-LNP vaccines also contain LNPs. Given that these vaccines can cause a cytokine storm and allergic reactions post vaccination, it is crucial to consider corticosteroids and measure IL-6 levels for effective management. Full article

In the spring of 2020, the SARS-CoV-2 pandemic presented a formidable challenge to national and global healthcare systems. Immunocompromised individuals or those with relevant pre-existing conditions were particularly at risk of severe coronavirus disease 2019 (COVID-19). Thus, understanding the immunological processes in these patient groups is crucial for current research. This study aimed to investigate humoral immunity following vaccination and infection in liver transplant recipients. Humoral immunity analysis involved measuring IgG against the SARS-CoV-2 spike protein (anti-S IgG) and employing a surrogate virus neutralization test (sVNT) for assessing the hACE2 receptor-binding inhibitory capacity of antibodies. The study revealed that humoral immunity post-vaccination is well established, with positive results for anti-S IgG in 92.9% of the total study cohort. Vaccinated and SARS-CoV-2-infected patients exhibited significantly higher anti-S IgG levels compared to vaccinated, non-infected patients (18,590 AU/mL vs. 2320 AU/mL, p < 0.001). Additionally, a significantly elevated receptor-binding inhibitory capacity was observed in the cPass^TMTM sVNT (96.4% vs. 91.8%, p = 0.004). Furthermore, a substantial enhancement of anti-S IgG levels (p = 0.034) and receptor-binding inhibition capacity (p < 0.001) was observed with an increasing interval post-transplantation (up to 30 years), calculated by generalized linear model analysis. In summary, fully vaccinated liver transplant recipients exhibit robust humoral immunity against SARS-CoV-2, which significantly intensifies following infection and with increasing time after transplantation. These findings should be considered for booster vaccination schemes for liver transplant recipients. Full article