Interdisciplinary Approach Is Essential for Sufficient Diagnosis and Therapy in Igg4-Related Disease Involving Multiple Organs

Introduction: IgG4-related disease (IgG4-RD) is a systemic, chronic inflammatory syndrome, with enlargement of involved organs, elevated serum levels of IgG4, dense lymphoplasmocytic infiltrates, rich in IgG4-positive plasma cells, and fibrosis in involved organs. The most frequently involved organs are the pancreato-hepatobiliary tract, salivary and lacrimal glands, the retroperitoneum, kidneys, lungs, and aorta. Often multiple organ systems are involved. As an initial treatment, glucocorticoids are recommended. In patients with relapse along with glucocorticoid dose reduction, various immunosuppressive agents have been reported. Aims & Methods: We reviewed 98 patients (2019-now) who were treated in the special outpatient unit for IgG4-RD at the University Hospital of Essen and identified 10 patients with IgG4-RD involving multiple organ systems. Result(s): The first patient is a 65-year-old male diagnosed with an IgG4- RD involving parotitis, lymphadenitis, sialadenitis with orbitopathy and elevated IgG4 serum level (7400 mg/l). Clinically response to therapy with steroids was documented. The second patient is a 63-year-old man with an IgG4-positive pancreatitis, sialadentis, lymphadenopathy, and elevated IgG4 serum level (3960 mg/l). Immunosuppression with tacrolimus leaded to clinical benefit. As the third patient, we report a 48-year-old man with IgG4-related inflammatory condition in pancreas and kidneys with high IgG4 serum levels. The patient was successfully treated with azathioprine and prednisolone. As the fourth patient, we demonstrate a 34-year-old man with IgG4-related autoimmune hepatitis, lymphadenitis, and pancreatitis. After treatment with tacrolimus in combination with rituximab, a significant decrease of IgG4-level was detected. The fifth patient, a 65-year-old man, was diagnosed with IgG4-related fibro- inflammatory pseudotumors in the liver, esophagitis, and lymphadenopathy combined with high serum levels of IgG4 (12000 mg/l). Clinically response to therapy with steroids and azathioprine was reported. As the sixth patient we demonstrate a 29-year-old male with IgG4-related lymphadenopathy, recurrent myocarditis, and pancreatitis. The patient has symptom-free episodes under low-dose prednisolone. We also found an IgG4-RD with multiple organ involvement in our seventh patient. A 54-year-old man with IgG4-related cholangitis, pancreatitis, prostatitis, and very high serum level of IgG4 (26700 mg/l) were treated with steroids and azathioprine. As our eight case, we present a 23-year-old man with congenital hepatic fibrosis, after living-donor liver transplantation, who developed an IgG4- related disease with high IgG4 serum levels (45300 mg/l) after infection with SARS-CoV-2. Pathologically enlarged lymph nodes were detected. In a biopsy of retroperitoneal lymph nodes, IgG4-positive plasma cells were detectable. Intestinal biopsies have shown numerous positive plasma cells in the IgG4-staining (40 IgG4 positive plasma cells/HPF). Treatment with rituximab is planned. The ninth patient is a 56-year-old woman with lymphadenitis and cholangitis, who clinically responded to a treatment with budesonide. As the last patient we present a 59-year-old man with an IgG4-related aortitis, cardiac fibrosis, cholangitis, hepatitis, exocrine pancreatic insufficiency and Hashimoto's thyroiditis responding very sufficient to rituximab. Conclusion(s): An interdisciplinary approach is essential for a sufficient diagnosis and therapy in IgG4-RD involving multiple organs. This collective is extremely heterogeneous, and treatment is often based on individual concepts.

Tongue immune compartment analysis reveals spatial macrophage heterogeneity.

The tongue is a unique muscular organ situated in the oral cavity where it is involved in taste sensation, mastication, and articulation. As a barrier organ, which is constantly exposed to environmental pathogens, the tongue is expected to host an immune cell network ensuring local immune defence. However, the composition and the transcriptional landscape of the tongue immune system are currently not completely defined. Here, we characterised the tissue-resident immune compartment of the murine tongue during development, health and disease, combining single-cell RNA-sequencing with in situ immunophenotyping. We identified distinct local immune cell populations and described two specific subsets of tongue-resident macrophages occupying discrete anatomical niches. Cx3cr1+ macrophages were located specifically in the highly innervated lamina propria beneath the tongue epidermis and at times in close proximity to fungiform papillae. Folr2+ macrophages were detected in deeper muscular tissue. In silico analysis indicated that the two macrophage subsets originate from a common proliferative precursor during early postnatal development and responded differently to systemic LPS in vivo. Our description of the under-investigated tongue immune system sets a starting point to facilitate research on tongue immune-physiology and pathology including cancer and taste disorders.

Low antibody titers after second SARSCoV- 2 vaccination in patients with autoimmune hepatitis

Aims/Background Patients with autoimmune hepatitis (AIH) require immunosuppressive treatment, which might impair the immune response to vaccination. In this prospective cohort study, we assessed the humoral immune response of AIH patients to SARS-CoV-2 vaccination. Methods Anti-SARS-CoV-2 antibody titers of 96 consecutive patients with AIH (78 % female, median age 53y, range 19-83y, 34 % with liver cirrhosis) were included 1-6 months after the second SARS-CoV-2 vaccination. Vaccination responses were explored for their association with prescribed immunosuppression, comorbidities and laboratory values. These data/findings were compared to 56 healthy controls. Results 93 (97 %) patients achieved a seroconversion with median anti-SARSCoV- 2 titers of 660 BAU/ml (range 20-11400 BAU/ml). A low or no response defined as antibody-titers < 100 BAU/ml was detected in 10 % (N = 10) of the patients, of which all were under immunosuppression (N = 4 azathioprine, 3 prednisone, 2 MMF + prednisone, 1 azathioprine + Tacrolimus). Antibody levels were significantly lower in AIH patients than in healthy controls (1700 BAU/ ml). Interestingly, antibody-titers of AIH patients without immunosuppression (n = 10) were comparably low to AIH patients with immunosuppression. No additional, individual risk factors for impaired response to vaccination could be identified in this cohort. Conclusion Despite high seroconversion rates, AIH patients show a significantly reduced magnitude of the humoral immune response. Therefore, these data suggest that AIH patients should be recommended an early third booster shot in agreement with recent advice by the German STIKO.