Serum IgG Levels Research Articles

Hard-to-treat autoimmune hepatitis and primary biliary cholangitis: The dawn of a new era of pharmacological treatment.

Patients with hard-to-treat autoimmune hepatitis (AIH) or primary biliary cholangitis (PBC) are defined a posteriori as those who do not show a sufficient response or are intolerant to pharmacological treatments, thus not achieving biochemical surrogate endpoints that are associated with long-term liver-related-event-free survival. The absence of a recently harmonized definition of 'complete biochemical response within 6 months (CBR≤6M)', which is defined as the normalization of serum transaminase and IgG levels below the upper limit of normal (ULN) at ≤6 months after treatment initiation is regarded as hard-to-treat AIH. The implementation of CBR≤6M, in turn, has been facilitating clinical trials, e.g., between azathioprine and mycophenolate mofetil, to reconsider appropriate first-line steroid sparing agents, leading to a reduction in the number of hard-to-treat AIH cases. Regarding PBC, one of the disseminated definitions of hard-to-treat patients is the absence of POISE criteria, which are evaluated at 12 months with serum alkaline phosphatase and bilirubin levels, after the introduction of ursodeoxycholic acid. Hard-to-treat PBC not meeting the POISE criteria has very recently been the target population for the U.S. FDA-approved second-line drugs, elafibranor and seladelpar. In future pharmacological treatment of AIH and PBC, the primary objective for AIH is likely to focus on lowering the number of hard-to-treat patients with personalized steroid sparing treatment regimens. A challenging goal in PBC treatment is the further optimization of treatment surrogate endpoints, even to the stricter ALP normalization, with which an indication of second- or later-line drugs might be expanded, but could ultimately lengthen patients' long-term survival.

T. Muris Infection Dynamics of a Fresh, Wild Isolate: Is the Established E Isolate Still Relevant?

For decades, parasitic worms such as Trichuris muris have been maintained in laboratory animals, providing insights into host-parasite interactions and host immune responses. The most used T. muris isolate is the E isolate, established in the laboratory in 1954. However, one concern with these model systems is the potential for laboratory-induced selection and therefore changes in host-parasite interactions. To address these concerns, we compare the E isolate with a recently isolated T. muris isolate (M isolate), established from wild house mice (Mus musculus domesticus, Isle of May, UK), in their capacity to infect laboratory mice. High dose infection of C57BL/6 mice revealed that significantly more parasites of the M isolate survived to the adult stage compared to the E isolate. Worm persistence was associated with heightened TNF-α and IL-10 secretion upon parasite-specific re-stimulation, and higher serum IgG1 and IgG2c levels, concomitant with an increase in T-bet+ and ICOS+ CD4+ T effector-memory cells. Differences in host response to the isolates were not as pronounced during low dose infection. Our study highlights the need for regular evaluation of lab-maintained parasite isolates against freshly isolated parasites to understand whether the established lab strains remain relevant model systems for our understanding of parasitic infections.

The immune responses elicited by six recombinant antigens of Mycoplasma hyopneumoniae in mice

Mycoplasma hyopneumoniae (M. hyopneumoniae) is the causative agent of swine enzootic pneumonia, resulting in substantial economic losses in global pig farming. Although vaccination is the primary strategy for controlling M. hyopneumoniae infection, current vaccines fall short in preventing transmission of this pathogen or protecting the body from secondary infection. This study aimed to assess the immunogenicity of six recombinant antigens (P97R1, P46, GAPDH, PdhA, DnaK, and EF-Tu) of M. hyopneumoniae through intramuscular immunization in mice. The results showed that the six antigens elicited high levels of serum IgG. Among them, P97R1, P46, PdhA, and DnaK stimulated robust antigen-specific IgA mucosal immune responses. CCK-8 assays revealed that both P97R1 and DnaK significantly increased the proliferation of mononuclear cells from spleen and lung, and DnaK also promoted the proliferation of blood mononuclear cells. Additionally, PdhA induced Th17-type immune response with a high level of IL-17 level in serum. Flow cytometry analysis indicated that P97R1 and PdhA increased the ratio of CD8+/CD4+ T lymphocyte, favoring cytotoxic T lymphocyte (CTL) immune responses. Notably, P97R1 immunization significantly decreased the percentages of CD4+ T cells while increased the percentages of CD8+ T cells. The present findings demonstrate that the candidate antigens P97R1, PdhA, and DnaK of M. hyopneumoniae induce specific humoral and mucosal immunity; P97R1 and DnaK also stimulated intense cellular immunity, and PdhA induced CTL and Th17-type immune responses. In conclusion, P97R1, PdhA, and DnaK emerge as potential candidate antigens for the future development of a more effective subunit vaccine against M. hyopneumoniae.

Clinical characteristics, imaging diagnostic accuracy, and prognosis of autoimmune pancreatitis: A real-world study in China.

In this study we aimed to comprehensively evaluate the clinical features and treatment outcomes of Chinese patients with autoimmune pancreatitis (AIP) through a single-center real-world study. Patients diagnosed with AIP in Changhai Hospital, Naval Medical University from January 2014 to December 2021 were included. Baseline characteristics, laboratory test results, cross-sectional imaging and endoscopic ultrasound (EUS) findings, and long-term follow-up data were obtained. The differences in these characteristics between type 1 and type 2 AIP patients were analyzed. Among all 320 patients, 271 (84.7%) and 49 (15.3%) had type 1 and type 2 AIP, respectively. The most common initial symptom was abdominal discomfort (58.1%), followed by obstructive jaundice (32.5%). Extrapancreatic organ involvement was identified in 126 (39.4%) patients, with the biliary system being the most commonly involved (36.6%). Elevated serum IgG4 level was rare in type 2 AIP patients. The diagnostic accuracy of computed tomography (CT), magnetic resonance imaging (MRI), and EUS for definitive and probable AIP were 78.0%, 68.7%, and 80.5%, respectively. EUS-guided tissue acquisition with immunohistochemical staining helped establish a final diagnosis in 39.7% of patients. During the follow-up period of 60 months, 18.6% of patients experienced relapse. The 1-, 3-, and 5-year relapse rates were higher in type 1 AIP patients, with an accumulated rate of 8.0%, 12.6%, and 15.1%, when compared with those with type 2 AIP. Type 2 AIP is not uncommon in Chinese population. The diagnostic accuracy of CT and EUS for AIP might be superior to that of MRI.

Expert consensus on the diagnosis and treatment of immunoglobulin-G4 related ophthalmic disease (2024 edition)

Immunoglobulin-G4 related ophthalmic disease (IgG4-ROD) is an immune-mediated fibroin flammatory condition characterized by ocular mass lesions and elevated plasma IgG4 level. Since all the ocular tissues can be involved, and it can be accompanied by multiple organ and systemic diseases, the diagnosis and treatment require multidisciplinary collaboration. The Oculoplastic and Orbital Disease Group of Chinese Ophthalmological Society of Chinese Medical Association and the Chinese Rheumatology Association convened experts in ophthalmology, and rheumatology and immunology, and formulated "Expert consensus on the diagnosis and treatment of immunoglobulin-G4 related ophthalmic disease (2024 edition)" for the diagnosis and treatment of IgG4-ROD based on domestic and international studies and experience. The consensus mainly standardized the diagnostic criteria of IgG4-ROD from the aspects of ocular imaging, serum IgG4 level and ocular histopathology, and recommended the methods and indications of drug therapy (glucocorticoids, immunosuppressants and biologics) and surgical treatment.

Intrathecal IgG and IgM synthesis correlates with neurodegeneration markers and corresponds to meningeal B cell presence in MS

Intrathecal synthesis of immunoglobulins (Igs) is a key hallmark of multiple sclerosis (MS). B cells are known to accumulate in the leptomeninges of MS patients and associate with pathology in the underlying cortex and a more severe disease course. However, the role of locally produced antibodies in MS brain pathology is poorly understood. Here, we quantified the protein levels of IgA, IgM, IgG and albumin in serum and cerebrospinal fluid (CSF) samples of 80 MS patients and 28 neurological controls to calculate Ig indices. In addition, we quantified presence of meningeal IgA+, IgM+ and IgG+ B cells in post-mortem brain tissue of 20 MS patients and 6 controls using immunostainings. IgM and IgG, but not IgA, indices were increased in CSF of MS patients compared to controls, with no observed differences between MS disease types. Both IgM and IgG indices correlated significantly with neurofilament light (NfL) levels in CSF, but not with clinical or radiological parameters of disease. Similarly, IgG+ and IgM+ B cells were increased in MS meninges compared to controls, whereas IgA+ B cells were not. Neuronal loss did not differ between sections with low or high IgA+, IgM+ and IgG+ B cells, but was increased in sections with high numbers of all CD19+ meningeal B cells. Similarly, high presence of CD19+ meningeal B cells and IgG+ meningeal B cells associated with increased microglial density in the underlying cortex. Taken together, intrathecal synthesis of IgG and IgM is elevated in MS, which corresponds to an increased number of IgG+ and IgM+ B cells in MS meninges. The significant correlation between intrathecal IgG and IgM production and NfL levels, and increased microglial activation in cortical areas adjacent to meningeal infiltrates with high levels of IgG+ B cells indicate a role for intrathecal IgM- and IgG-producing B cells in neuroinflammatory and degenerative processes in MS.

Recombinant Lactiplantibacilllus plantarum modulate gut microbial diversity and function

BackgroundGut microbes are important regulators of host health and can also function as disease indicators. Lactiplantibacilllus plantarum(L. plantarum)used as express and delivery vaccines for mucosal immunity have been shown to activate specific immune responses in numerous studies.ResultsThe interaction between recombinant L. plantarum and the gut microbiota was investigated in this study. The results indicated a change in the amount of gut OTU by recombinant L. plantarum. Recombinant L. plantarum dramatically boosted the species diversity of gut bacteria based on the Shannon-Wiener index. Beta diversity analysis showed that microbial structure was changed by recombinant L. plantarum. Furthermore, recombinant NC8 L. plantarum expressing a fusion between the P14.5 protein of the African swine fever virus and IL-33 enhanced the functions of gut bacteria in metabolism and immune regulation. Increased levels of IgG and IgG1 in serum and sIgA in feces, as well as enrichment of CD4+ T cells and IgA+ B cells, indicated that the gut microbiota exerted an immunomodulatory role when mediated by recombinant L. plantarum.ConclusionsThese results revealed that recombinant L. plantarum exerted its potential role in the gut microbiota and gut immunity.These fndings contribute to a broader understanding and utilization of L. plantarum bacteria in various therapeutic applications.

Effects of Bacterial Lysates on TLRs/NF-κB Pathway, Immune Function, and Prognosis in Children with Pulmonary Infection Caused by Streptococcus pneumoniae

Background: Bacterial lysates, as immunomodulators, may play a role in regulating the host immune response. Objectives: This study aimed to investigate the effects of bacterial lysates OM85-BV in treating pulmonary infections caused by Streptococcus pneumoniae in children. Methods: A total of 120 children with S. pneumoniae pulmonary infection were divided into two groups: The control group and the OM85-BV group, with a 1: 1 ratio. The control group received intravenous mezlocillin at 100 mL/kg/d, while the OM85-BV group, in addition to mezlocillin, received OM85-BV orally at 3.5 mg per dose. The improvement of clinical symptoms and pulmonary function indexes—including respiratory rate, tidal volume, volume to peak expiratory flow as a proportion of exhaled volume, and time to peak tidal expiratory flow as a proportion of expiratory time—were compared. Additionally, levels of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), soluble interleukin-2 receptor (sIL-2R), T lymphocyte subsets, and immunoglobulins in serum were analyzed. Results: Compared to the control group, the OM85-BV group showed a significant decrease in respiratory rate and an increase in tidal volume, volume to peak expiratory flow, and time to peak tidal expiratory flow (P < 0.05 for all). The OM85-BV group also had significantly lower levels of serum inflammatory factors such as CRP, TNF-α, IL-6, and sIL-2R. In terms of immune function, the OM85-BV group showed increased levels of T lymphocyte subsets CD3+, CD4+, and CD4+/CD8+ ratios, with a decrease in CD8+, as well as elevated serum IgA and IgG levels. The total effective rate of treatment in the OM85-BV group was significantly higher than in the control group (P < 0.05). Conclusions: The addition of OM85-BV to the treatment of S. pneumoniae pulmonary infection in children significantly improves clinical symptoms, lung function, and immune function, while reducing the inflammatory response. OM85-BV appears to inhibit the activation of the toll-like receptors (TLRs) and nuclear factor kappa-B (NF-κB) pathway.

Assessment of the Impact of Dietary Supplementation with Epigallocatechin Gallate (EGCG) on Antioxidant Status, Immune Response, and Intestinal Microbiota in Post-Weaning Rabbits.

This study was conducted to investigate the impact of EGCG on antioxidant stress, immune response, and intestinal microbiota flora in post-weaning rabbits. A total of 144 40 d Ira rabbits (equally divided by sex), were randomly allocated to six treatments. with five groups receiving doses of 200, 400, 600, 800, and 1000 mg/kg of EGCG, while one group served as a control without EGCG. Over 48 days, this study the assessed growth performance, antioxidant capacity, immune system, intestinal morphology, and cecal microbiota in the rabbits. The results showed that EGCG did not affect growth performance; however, significant linear and quadratic correlations were observed between the MDA, T-AOC, and GSH-Px activities in the liver and jejunum (p < 0.05). Quadratic effects were observed for the spleen and thymus indexes and serum IgG levels with increasing EGCG dosages (p < 0.05). Additionally, positive linear and quadratic effects were found on the ileal villus height and the villus height/crypt depth ratio. The relative abundances of Euryarchaeota, Patescibacteria, and Synergistota were significantly enriched in rabbits fed with high dosages (600-1000 mg/kg) of EGCG. Conclusively, the addition of large doses of EGCG (400-800 mg/kg) can effectively suppress oxidative stress and alleviate weaning stress, thereby contributing to the protection of post-weaning rabbits.

Advanced chelate technology-based trace minerals reduce inflammation and oxidative stress in Eimeria-infected broilers by modulating NF-kB and Nrf2 pathways

This study investigated the effects of substituting inorganic trace minerals (ITM) with advanced chelate technology-based TM (ACTM) in broiler chicken feed on productive performance, metabolic profile, humoral immunity, antioxidant status, and modulation of NF-kB and Nrf2 signaling pathways in mixed Eimeria species exposure. The study involved 480 newly hatched male broiler chickens, which were divided into 5 treatment groups, each with 6 replicate cages and 16 chickens per replicate. The experimental treatments included an uninfected negative control group fed a basal diet with recommended inorganic TM levels (NC), an infected positive control group fed the same diet (PC), a PC group supplemented with salinomycin (SAL), and two PC groups in which the basal diet was replaced with 50% and 100% ACTM instead of inorganic TM (ACTM50 and ACTM100, respectively). All groups, except for the NC group, were orally challenged with mixed Eimeria species oocysts on day 14. According to the results, the PC group showed lower feed intake, breast yield, low-density lipoprotein-cholesterol concentration, lactobacillus spp. counts, and serum IgG levels, but higher jejunal TGF-β expression versus the NC group. The broilers in the NC, SAL, and ACTM100 groups showed higher body weight gain, carcass yield, and TGF-β expression, but lower serum alkaline phosphatase activity, ileal E. coli count, and jejunal expression levels of IL-1β, IL-6, IFN-γ, Nrf2, and SOD1 compared to the PC group, with the NC group having the highest body weight gain and lowest IL-1β and Nrf2 expression levels. Furthermore, the administration of ACTM100 treatment improved feed efficiency, increased serum iron, zinc, manganese, and copper levels, enhanced total antioxidant capacity and different antioxidant enzyme activities, and reduced malondialdehyde concentration. In conclusion, complete replacement of ITM with ACTM effectively protects broilers from Eimeria infection, with similar positive effects to SAL treatment in terms of productive performance and anti-inflammatory responses and better antioxidant responses and mineral availability.

Association of Celiac Disease and H. pylori Infection with ATG5 Polymorphism and Interleukin-33

Background: Celiac disease (CD) is an inflammatory small intestine autoimmune disease. The study aims to investigate the association and the detection of ATG5 polymorphism between celiac disease (CD) and H. pylori infection, and the association with Interleukin-33 (IL-33).Methods: The study groups included patients from Iraq, ages 4 to 35. Two primary patient groups were created: sixteen had positive H. pylori and celiac disease, and thirty had positive CD and negative H. pylori disease. The levels of tissue transglutaminase IgA (TTG IgA), H. pylori IgG, and IL-33 were measured using the ELISA method. The primers were amplified using PCR.Results: With celiac disease, the patient group's TTG IgA levels increased dramatically. The test also showed significant variations (P=0.054) in the H. pylori IgG levels between the patient and control groups. The H. pylori seropositivity test showed a statistically significant difference (p ≤0.033) between seropositive and seronegative individuals, while the patient group's IL-33 levels did not significantly differ (P ≤0.299) from the control group.Conclusions: Our results showed that CD is more common in women and occurs in the age range of 24-35 years. It also showed that the mutant variant of ATG5 is associated with CD, and the significance of H. pylori IgG serum levels in the patient group may indicate that the bacteria involved in CD. Furthermore, H. pylori infection is more strongly linked to serum IL-33 levels than CD.Keywords: Celiac disease; H. pylori; PCR; IL-33; ATG5 polymorphism

Responses of Intestinal Antioxidant Capacity, Morphology, Barrier Function, Immunity, and Microbial Diversity to Chlorogenic Acid in Late-Peak Laying Hens.

This study examined the influence of chlorogenic acid (CGA) on gut antioxidant status, morphology, barrier function, immunity, and cecal microbiota in late-peak laying hens. A total of 240 Hy-Line Brown hens, aged 43 weeks, were randomly assigned to four groups, the basal diet +0, 400, 600, and 800 mg/kg CGA, for 12 weeks. The results revealed that CGA significantly reduced ileal H2O2 and malondialdehyde levels; increased duodenal height, ileal villus height, and villus height-to-crypt depth ratio; while decreasing jejunal crypt depth. The 600 and 800 mg/kg CGA significantly upregulated the duodenal, jejunal, and ileal ZO-1 and occludin gene expression; increased IgG levels in serum and ileum; and upregulated ileal IgA gene expression. The 600 mg/kg CGA significantly upregulated CD3D and CD4 gene expression, while downregulating IL-1β gene expression in duodenum, jejunum, and ileum. Moreover, CGA changed the gut microbiota structure. The SCFA-producing bacteria unclassified_f__Peptostreptococcaceae, unclassified_f_Oscillospiraceae, Pseudoflavonifractor, Lachnospiraceae_FCS020_group, Oscillospira, Elusimicrobium, Eubacterium_ventriosum_group, Intestinimonas, and norank_f_Coriobacteriales_Incertae_Sedis were significantly enriched in the 400, 600, and/or 800 mg/kg CGA groups. The bacteria Lactobacillus, Bacillus, and Akkermansia were significantly enriched in the 600 mg/kg CGA group. Conclusively, dietary CGA (600-800 mg/kg) improved intestinal antioxidant status, morphology, barrier and immune function, and beneficial microbiota growth in late-peak laying hens.

Inactivated vaccine dosage and serum IgG levels correlate with persistent COVID-19 infections in hematologic malignancy patients during the Omicron Surge in China

PurposeThe essence of this scholarly work was to carefully outline the key factors intensifying the virulence and protracted contagion of COVID-19, particularly among individuals afflicted with hematologic malignancies (HM), in an epoch predominantly governed by the Omicron variant.MethodsAdults with HM diagnosed with COVID-19 from November 2022 to February 2023 were monitored in this retrospective study. Patient blood samples yielded biochemical data, and COVID-19 was confirmed through RNA or antigen testing. The factors affecting severity and infection duration were examined using both univariate and multivariate logistic regression analyses. For calculating the overall survival probabilities, the Kaplan–Meier product limit approach was employed.ResultsIn the examined cohort, 133 individuals diagnosed with HM and concomitantly infected with COVID-19 were scrutinized. Of the participants, 29.3% (39 patients) were classified as Severe/Critical, while the other 70.7% (94 patients) were categorized as Non-severe. A significant difference was observed in vaccination status: 61.7% of patients in the Non-severe group had received at least a two-dose vaccine regimen, whereas 61.5% of the Severe/Critical group had either minimal or only one dose of vaccination. The data analysis revealed that elevated C-reactive protein levels (≥ 100 mg/L) significantly raised the risk of severe/critical conditions in HM patients with COVID-19, as determined by advanced multivariate logistic regression. The odds ratio was 3.415 with a 95% confidence interval of 1.294–9.012 (p = 0.013). Patients who continued to have positive nucleic acid tests and ongoing symptoms beyond 30 days were categorized as having a persistent infection, whereas those who achieved infection control within this timeframe were categorized as having infection recovery. Of the HM cohort, 11 did not survive beyond 30 days after diagnosis. The results from a competing risk model revealed that increased interleukin-6 levels (HR: 2.626, 95% CI: 1.361–5.075; p = 0.004) was significantly associated with persistent infection. Conversely, receiving more than two vaccine doses (HR: 0.366, 95% CI: 0.158–0.846; p = 0.019), and having high IgG levels (≥ 1000 mg/dl) (HR: 0.364, 95% CI: 0.167–0.791; p = 0.011), were associated with infection recovery. There was a notable disparity in survival rates between patients with persistent infections and infection recovery, with those in the non-persistent group demonstrating superior survival outcomes (P < 0.001).ConclusionsIn conclusion, the study determined that HM patients with COVID-19 and increased C-reactive protein levels had a higher likelihood of severe health outcomes. Persistent infection tended to be more prevalent in those with vaccine dosages (< 2 doses), lower IgG levels, and higher interleukin-6 levels.

Evaluation of Antibody Response and Reinfection in Improved Hypertensive, Cardiac, and Diabetic Patients with COVID-19 for Six Months in Unvaccinated Outpatients

Background: This study presents a unique investigation into the relationship between the persistence of IgG antibody levels and reinfection in recovered coronavirus disease 2019 (COVID-19) patients. By shedding light on this aspect, we aim to address concerns about the risk of reinfection in unvaccinated patients, offering a fresh perspective in the current COVID-19 research landscape. Objectives: This study takes a novel approach by focusing on the antibody response and reinfection in COVID-19 patients who were treated in outpatient settings for six months. This approach distinguishes our research within the broader context of COVID-19 studies. Methods: Our comprehensive and rigorous prospective cohort study included 149 COVID-19 outpatients referred to Imam Ali Clinic in Dezfoul City, Khuzestan province, Iran. Data was meticulously collected from September 2021 to February 2022. All unvaccinated patients underwent RT-PCR testing, and their anti-SARS-CoV-2 IgM/IgG levels were measured at the onset of illness. Serum IgG levels were then measured again after three and six months using ELISA. Results: All COVID-19 patients had their IgG antibody levels tested three times (on days two to four of the illness, at three months, and at six months). Significant differences in IgG antibody levels were observed between the vaccinated and unvaccinated groups during each period (P &lt; 0.05). Additionally, there were substantial differences between the hypertension and non-hypertension groups (P = 0.032). Importantly, our findings reaffirm the impartiality of our research, as no significant differences were found between reinfection rates and various demographic or disease-related factors. Conclusions: The findings of this study suggest that high levels of IgG antibodies in unvaccinated patients could potentially reduce the risk of reinfection. This insight could have important implications for public health strategies and the management of COVID-19 in unvaccinated populations, providing valuable information for decision-makers in the field.

Experience in treating patients with autoimmune pancreatitis

Objective — to establish the main diagnostic signs of autoimmune pancreatitis and aspects of patient treatment. Materials and methods. The study analyzed the results of examination and treatment of 17 patients with autoimmune pancreatitis (AIP) from 2010 to 2022. Among the total number of patients with AIP, there were 11 men (65%) and 6 women (35%). The average age of the patients was 52.4 years. Among all patients with AIP, focal involvement of the pancreas was found in 3 (18%) patients, with a predominant involvement of the head of the pancreas. Segmental form of AIP was diagnosed in 6 (35%) patients, while diffuse form was found in 8 (47%) patients. Type 1 AIP was identified in 13 (76%) patients, and type 2 AIP in 4 (24%) patients. For all patients suspected of AIP, the HISORt criteria were assessed: instrumental visualization, serological and histological verification, determination of the volume of pancreatic involvement, and response to steroid therapy. Results. Recurrence of AIP was observed in 8 (47.0%) patients with type 1 AIP and 1 (5.8%) patient with type 2 AIP. AIP recurred in patients with proximal bile duct involvement, diffuse pancreatic involvement, persistently elevated IgG4 levels after steroid induction, delayed radiological remission, and damage to more than two organs. Increased serum levels of IgG, IgG4, apnd eosinophilia indicated a recurrence of IgG4‑RD. A repeat induction of steroids was performed in patients with recurrent AIP, which proved to be very effective, resulting in high remission rates, specifically in 7 (70%) patients with type 1 AIP and in 1 (100%) patient with type 2 AIP. Among all AIP patients that were operated on, 3 (40%) underwent Roux‑en‑Y hepaticojejunostomies, 1 (20%) pancreaticoduodenectomy, and 1 (20%) a Frey procedure. Conclusions. The low incidence of AIP necessitates the use of a clear diagnostic algorithm, and the peculiarities of the disease’s course require compliance with all the principles of conservative treatment and surgical interventions in case of surgical complications.

Palygorskite improves growth performance and prevents liver damage in avian pathogenic Escherichia coli-challenged broiler chickens at an early age.

Avian pathogenic Escherichia coli (APEC) is a major bacterial infection that causes economic losses in the global poultry industry. Palygorskite (PAL) has been shown to enhance growth performance while improving antioxidative and anti-inflammatory properties of broilers. This study evaluated the protective effects of PAL on growth performance and liver function in broilers subjected to APEC challenge. A total of 320 one-day-old male Arbor Acres chicks were divided into four groups with eight replicates of ten birds each, based on a 2×2 factorial arrangement (basal diet or 5g/kg PAL-supplemented diet) and inoculation (bacterial culture medium or APEC). PAL increased body weight gain (BWG) prior to APEC challenge (P < 0.05). However, APEC caused losses in BWG, feed intake (FI), and feed efficiency, along with increased relative hepatic weight, hepatic pathology scores, and hepatic-cell apoptosis rate (P < 0.05). Compared to normal birds, APEC increased interleukin (IL)-1β, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), and nitric oxide (NO) levels, as well as lysozyme (LZM) and myeloperoxidase (MPO) activities, while decreasing total antioxidant capacity (T-AOC) and IL-10 levels, and total superoxide dismutase (T-SOD) and catalase (CAT) activities in both serum and liver, APEC also raised alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, but reduced total protein (TP), albumin (ALB), immunoglobulin (Ig) A, IgG, and IgM levels in serum (P < 0.05). Moreover, APEC increased hepatic mRNA level of IL-1β, IFN-γ, TNF-α, nuclear factor kappa B, and inducible nitric oxide synthase (iNOS), while inhibited mRNA level of IL-10 (P < 0.05). In contrast, PAL increased BWG and FI, alleviated hepatic-cell apoptosis rate during the challenge period (P < 0.05). An incorporation of PAL reduced triglyceride and NO contents, ALT and AST activities, while increasing TP, ALB, IL-10, IgG, and IgM levels in serum, enhancing serum T-SOD and CAT activities, elevating hepatic T-AOC and CAT activities, inhibiting hepatic MDA accumulation, and reducing IL-1β levels and LZM activity in both liver and serum (P < 0.05). An interactive effect was found for hepatic TNF-α and iNOS mRNA expression, in which PAL inhibited their mRNA expression in APEC-challenged birds (P < 0.05). Overall, PAL addition partially mitigated the negative impact of APEC challenge on growth performance and liver function of broiler chicks at an early age.

High Prevalence of Anti-Prothrombin IgM and IgG Autoantibodies in Women With Unexplained Recurrent Pregnancy Loss.

To investigate the association between anti-prothrombin IgM and IgG antibodies and recurrent pregnancy loss (RPL) in a cohort of Lebanese women, and their impact on pregnancy outcomes. This was a retrospective case-control study involving 207 women with RPL and 179 age-matched multiparous controls. Quantitative sandwich ELISA assayed anti-prothrombin IgM and IgG antibodies. Univariate and multivariate logistic regression were employed to assess the risk imparted by anti-prothrombin antibodies, while ROC analysis was used to determine their sensitivity and specificity. Our study revealed that women with RPL had significantly higher serum levels of anti-prothrombin IgM and IgG than controls. Univariate regression analysis demonstrated that elevated anti-prothrombin IgM (OR = 1.13; 95% CI = 1.07, 1.19; P < 0.001) and IgG (OR = 1.05; 95% CI = 1.03, 1.08; P < 0.001) were associated with increased RPL risk. Multivariate analysis confirmed these findings, indicating that anti-prothrombin IgM (aOR = 1.13; 95% CI = 1.05, 1.20; P < 0.001) and IgG (aOR = 1.08; 95% CI = 1.05, 1.11; P < 0.001) are independent risk factors. ROC analysis yielded an AUC of 0.720 for IgM and 0.649 for IgG, underscoring their predictive value and offering hope for improved risk assessment and management of RPL. Elevated levels of anti-prothrombin IgM and IgG are significantly associated with RPL, suggesting an autoimmune component to pregnancy loss. These findings highlight the importance of screening for these antibodies in women with unexplained RPL to guide management and therapeutic strategies.

8301 A Rare Case of IgG4-Related Hypophysitis

Abstract Disclosure: P. Kesavan Chary: None. J.M. Silverstein: None. Background: IgG4-related disease (IgG4-RD) is an immune-mediated condition that presents as systemic inflammation and fibrosis of tissues, often affecting multiple organs. Isolated IgG4-related Hypophysitis is rare and characterized by lymphoplasmacytic infiltration of the pituitary gland by IgG4-positive plasma cells. A combination of clinical, serologic, radiologic, and histopathologic findings is used for diagnosis of IgG4-RD and approximately two-thirds of all patients have elevated serum IgG4 levels. We report a case of isolated IgG4-related Hypophysitis in a middle-aged woman serologically negative for IgG4-related disease. Case Report: A 52 year old female with history of steroid dependent severe persistent asthma, allergic rhinitis, and chronic sinusitis presented with one month of headache, polyuria, and polydipsia. MRI Brain demonstrated an enlarged, rounded pituitary gland 16 x 11 x 9 mm, with homogeneous enhancement, extension into the suprasellar cistern, and mild thickening of the infundibulum suspected to represent a pituitary adenoma. Lab evaluation revealed mild hyperprolactinemia (prolactin 83.2, normal 4.8-23.3 ng/mL) and secondary adrenal insufficiency based on an abnormal high-dose cosyntropin stimulation test in the setting of a low adrenocorticotrophic hormone (ACTH) level (&amp;lt;2.0 pg/mL). Remaining pituitary hormone levels were normal. Inpatient work-up for polyuria and polydipsia showed a low urine specific gravity of 1.003. An overnight water deprivation test was performed. Baseline urine osmolality (UOsm) was 95 mOsm/kg and serum sodium was 144 mmol/L; after 3 hours of water deprivation, serum Osm increased to 301 mOsm/kg (275-300 mOsm/kg) and UOsm only to 215 mOsm/kg, while her sodium increased to 145 mmol/L. Results were felt to be consistent with AVP deficiency (Central Diabetes Insipidus) and the patient was started on desmopressin. Because of the presence of AVP deficiency, further work-up was done to evaluate for an infiltrative process or malignancy. ANA, RPR, ESR, CRP, CBC, ACE level, T-SPOT, and IgG subclasses were unremarkable. Further imaging studies yielded a negative nuclear bone scan and PET/CT scan. For diagnostic purposes, the patient underwent biopsy via an endoscopic endonasal transsphenoidal approach. Pathology showed the presence of &amp;gt;10 IgG4+ plasma cells in a single high-power field, consistent with a diagnosis of IgG4-related Hypophysitis. Conclusion: Isolated IgG4-related Hypophysitis is the least common clinical presentation of IgG4-RD, which is itself a rare and relatively newly recognized condition. IgG4-related Hypophysitis should be suspected in patients presenting with AVP deficiency and pituitary stalk enlargement with an otherwise negative work up. Presentation: 6/2/2024

Humoral signatures of Caspr2-antibody spectrum disorder track with clinical phenotypes and outcomes.

Immunoglobulin (Ig) G4 auto-antibodies (Abs) against contactin-associated protein-like 2 (Caspr2), a transmembrane cell adhesion protein expressed in the central and peripheral nervous system, are found in patients with a broad spectrum of neurological symptoms. While the adoptive transfer of Caspr2-specific IgG induces brain pathology in susceptible rodents, the mechanisms by which Caspr2-Abs mediate neuronal dysfunction and translate into clinical syndromes are incompletely understood. We use a systems-level approach combined with high-dimensional characterization of Ab-associated immune features to deeply profile humoral biosignatures in patients with Caspr2-Ab-associated neurological syndromes. We identify two signatures strongly associated with two major clinical phenotypes, limbic encephalitis (LE) and predominant peripheral nerve hyperexcitability without LE (non-LE). Caspr2-IgG Fc-driven pro-inflammatory features, characterized by increased binding affinities for activating Fcγ receptors (FcγRs) and C1q, along with a higher prevalence of IgG1-class Abs, in addition to IgG4, are strongly associated with LE. Both the occurrence of Caspr2-specific IgG1 and higher serum levels of interleukin (IL)-6 and IL-15, along with increased concentrations of biomarkers reflecting neuronal damage and glial cell activation, are associated with poorer clinical outcomes at 1-year follow-up. The presence of IgG1 isotypes and Fc-mediated effector functions control the pathogenicity of Caspr2-specific Abs to induce LE. Biologics targeting FcR function might potentially restrain Caspr2-Ab-induced pathology and improve clinical outcomes. This study was funded by a German-French joint research program supported by the German Research Foundation (DFG) and the Agence Nationale de la Recherche (ANR) and by the Interdisciplinary Centre for Clinical Research (IZKF) Münster.

Interleukin 9 mediates T follicular helper cell activation to promote antibody responses.

Antigen-specific humoral responses are orchestrated through complex interactions among immune cells in lymphoid tissues, including the collaboration between B cells and T follicular helper (Tfh) cells. Accumulating evidence indicates a crucial role for interleukin-9 (IL-9) in the formation of germinal centers (GCs), enhancing the generation of class-switched high-affinity antibodies. However, the exact function of IL-9 in Tfh cell regulation remains unclear. In this study, we examined the humoral immune responses of CD4Cre/+Il9rafl/fl mice, which lack an IL-9-specific receptor in Tfh cells. Upon intraperitoneal immunization with sheep red blood cells (SRBCs), CD4Cre/+Il9rafl/fl mice displayed diminished levels of SRBC-specific IgG antibodies in their sera, along with reduced levels of GC B cells and plasma cells. Notably, Il9ra-deficient Tfh cells in the spleen exhibited decreased expression of their signature molecules such as B-cell lymphoma 6, C-X-C chemokine receptor 5, IL-4, and IL-21 compared to control mice. In models of allergic asthma induced by house dust mite (HDM) inhalation, CD4Cre/+Il9rafl/fl mice failed to elevate serum levels of HDM-specific IgE and IgG. This was accompanied by reductions in Tfh cells, GC B cells, and plasma cells in mediastinal lymph nodes. Furthermore, group 2 innate lymphoid cells (ILC2s) were identified as producers of IL-9 under immunizing conditions, possibly induced by leukotrienes released by activated IgD+ B cells around the T-B border. These observations may indicate the critical role of IL-9 receptor signaling in the activation of Tfh cells, with ILC2s potentially capable of supplying IL-9 in organized lymphoid tissues.