Tryptase Levels Research Articles

Deciphering the function of Xiangsha-Liujunzi-Tang in enhancing duodenal mucosal barrier by inhibiting MC/Tryptase/PAR-2 signaling pathway in functional dyspepsia rats

Ethnopharmacological relevanceXiangsha-Liujunzi-Tang (XSLJZT) is a classical formula for treating the diseases of digestive system, which can effectively and significantly improve the symptoms of functional dyspepsia (FD) patients. The main function of XSLJZT is to benefit Qi and spleen, and harmonize stomach. Aim of the studyThe purpose of this study was to investigate the intervention effect of XSLJZT on duodenal mucosal injury in FD rats and the response mechanism of MC/Tryptase/PAR-2 signal pathway. Materials and methodsUltra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was employed to qualitatively and quantitatively identify the chemical component of XSLJZT. A comprehensive modeling method (iodoacetamide infusion + irregular diet + swimming exhaustion) was used to construct the FD rat model. XSLJZT decoction was given to intervene FD rats for 2 weeks. The indicators of digestive function including body mass, 3-h food intake, visceral sensitivity, gastric emptying rate and intestinal propulsion rate were routinely measured for FD rats. The pathological changes of duodenum and microstructure of intestinal epithelial cells were observed by HE staining and transmission electron microscopy respectively. The inflammatory factors (VCAM-1, IL-6, TNF-α, and ICAM-1) and histamine content were evaluated by enzyme-linked immunosorbent assay (ELISA). The expression levels of Tryptase, PAR-2, ZO-1, β-catenin, p–NF–κBp65 and p-ERK1/2 in duodenal tissues were measured by Western blot (WB) and immunofluorescence colony-staining (IFC). ResultsXSLJZT administration significantly improved the survival of FD rats, increased body mass and 3-h food intake, improved visceral sensitivity, and restored gastric emptying rate and intestinal propulsion rate. HE staining showed that XSLJZT recovered the structure of duodenal mucosal and reduced inflammatory infiltration. ELISA revealed that XSLJZT reduced the content of inflammatory factors (VCAM-1, IL-6, TNF-α, and ICAM-1) and histamine. In addition, WB and IFC uncovered that the protein levels of ZO-1 and β-catenin were up-regulated and MC/Tryptase/PAR-2 signaling pathway was inhibited by XSLJZT. ConclusionXSLJZT significantly improved the integrity of duodenal mucosa and decreased the inflammation in FD rats through the inhibition of MC/Tryptase/PAR-2 signaling pathway response.

Avapritinib versus Placebo in Indolent Systemic Mastocytosis

BackgroundIndolent systemic mastocytosis (ISM) is a clonal mast-cell disease driven by the KIT D816V mutation. We assessed the efficacy and safety of avapritinib versus placebo, both with best supportive care, in patients with ISM.MethodsWe randomized patients with moderate to severe ISM (total symptom score [TSS] of ≥28; scores range from 0 to 110, with higher numbers indicating more severe symptoms) two to one to avapritinib 25 mg once daily (n=141) or placebo (n=71). The primary end point was mean change in TSS based on the 14-day average of patient-reported severity of 11 symptoms. Secondary end points included reductions in serum tryptase and blood KIT D816V variant allele fraction (≥50%), reductions in TSS (≥50% and ≥30%), reduction in bone marrow mast cells (≥50%), and quality of life measures.ResultsFrom baseline to week 24, avapritinib-treated patients had a decrease of 15.6 points (95% CI, −18.6 to −12.6) in TSS compared to a decrease of 9.2 points (−13.1 to −5.2) in the placebo group; P<0.003. From baseline to Week 24, 76/141 patients (54%; 45% to 62%) in the avapritinib group compared to 0/71 patients in the placebo group achieved a ≥50% reduction in serum tryptase level; P<0.001. Edema and increases in alkaline phosphatase were more common with avapritinib than placebo; there were few treatment discontinuations because of adverse events.ConclusionsIn this trial, avapritinib was superior to placebo in reducing uncontrolled symptoms and mast-cell burden in patients with ISM. The long-term safety and efficacy of this approach for patients with ISM remain the focus of the ongoing trial. (Funded by Blueprint Medicines Corporation; ClinicalTrials.gov number, NCT03731260.)

Anaphylatoxin Complement 5a in Pfizer BNT162b2-Induced Immediate-Type Vaccine Hypersensitivity Reactions.

The underlying immunological mechanisms of immediate-type hypersensitivity reactions (HSR) to COVID-19 vaccines are poorly understood. We investigate the mechanisms of immediate-type hypersensitivity reactions to the Pfizer BNT162b2 vaccine and the response of antibodies to the polyethylene glycol (PEG)ylated lipid nanoparticle after two doses of vaccination. Sixty-seven participants, median age 35 and 77.3% females who tolerated two doses of the BNT162b2 vaccine (non-reactors), were subjected to various blood-sampling time points. A separate group of vaccine reactors (10 anaphylaxis and 37 anonymised tryptase samples) were recruited for blood sampling. Immunoglobulin (Ig)G, IgM and IgE antibodies to the BNT162b2 vaccine, biomarkers associated with allergic reaction, including tryptase for anaphylaxis, complement 5a(C5a), intercellular adhesion molecule 1 (ICAM-1) for endothelial activation and Interleukin (IL)-4, IL-10, IL-33, tumour necrosis factor (TNF) and monocyte chemoattractant protein (MCP-1), were measured. Basophil activation test (BAT) was performed in BNT162b2-induced anaphylaxis patients by flow cytometry. The majority of patients with immediate-type BNT162b2 vaccine HSR demonstrated raised C5a and Th2-related cytokines but normal tryptase levels during the acute reaction, together with significantly higher levels of IgM antibodies to the BNT162b2 vaccine (IgM 67.2 (median) vs. 23.9 AU/mL, p < 0.001) and ICAM-1 when compared to non-reactor controls. No detectable IgE antibodies to the BNT162b2 vaccine were found in these patients. The basophil activation tests by flow cytometry to the Pfizer vaccine, 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol (DMG-PEG) and PEG-2000 were negative in four anaphylaxis patients. Acute hypersensitivity reactions post BNT162b2 vaccination suggest pseudo-allergic reactions via the activation of anaphylatoxins C5a and are independent of IgE-mechanisms. Vaccine reactors have significantly higher levels of anti-BNT162b2 IgM although its precise role remains unclear.

Systemic mastocytosis in adults: 2023 update on diagnosis, risk stratification and management.

Systemic mastocytosis (SM) results from clonal proliferation of mast cells (MC) in extracutaneous organs. The major criterion is presence of multifocal MC clusters in the bone marrow and/or extracutaneous organs. Minor diagnostic criteria include elevated serum tryptase level, MC CD25/CD2/CD30 expression, and presence of activating KIT mutations. Establishing SM subtype as per the International Consensus Classification/World Health Organization classification systems is an important first step. Patients either have indolent/smoldering SM (ISM/SSM) or advanced SM, including aggressive SM (ASM), SM with associated myeloid neoplasm (SM-AMN), and mast cell leukemia. Identification of poor-risk mutations (i.e., ASXL1, RUNX1, SRSF2, NRAS) further refines the risk stratification. Several risk models are available to help assign prognosis in SM patients. Treatment goals for ISM patients are primarily directed toward anaphylaxis prevention/symptom control/osteoporosis treatment. Patients with advanced SM frequently need MC cytoreductive therapy to reverse disease-related organ dysfunction. Tyrosine kinase inhibitors (TKI) (midostaurin, avapritinib) have changed the treatment landscape in SM. While deep biochemical, histological and molecular responses have been documented with avapritinib treatment, its efficacy as monotherapy against a multimutated AMN disease component in SM-AMN patients remains unclear. Cladribine continues to have a role for MC debulking, whereas interferon-α has a diminishing role in the TKI era. Treatment of SM-AMN primarily targets the AMN component, particularly if an aggressive disease such as acute leukemia is present. Allogeneic stem cell transplant has a role in such patients. Imatinib has a therapeutic role only in the rare patient with an imatinib-sensitive KIT mutation.

Mast cell deficiency prevents BCR::ABL1 induced splenomegaly and cytokine elevation in a CML mouse model

The persistence of leukemic stem cells (LSCs) represents a problem in the therapy of chronic myeloid leukemia (CML). Hence, it is of utmost importance to explore the underlying mechanisms to develop new therapeutic approaches to cure CML. Using the genetically engineered ScltTA/TRE-BCR::ABL1 mouse model for chronic phase CML, we previously demonstrated that the loss of the docking protein GAB2 counteracts the infiltration of mast cells (MCs) in the bone marrow (BM) of BCR::ABL1 positive mice. Here, we show for the first time that BCR::ABL1 drives the cytokine independent expansion of BM derived MCs and sensitizes them for FcεRI triggered degranulation. Importantly, we demonstrate that genetic mast cell deficiency conferred by the Cpa3Cre allele prevents BCR::ABL1 induced splenomegaly and impairs the production of pro-inflammatory cytokines. Furthermore, we show in CML patients that splenomegaly is associated with high BM MC counts and that upregulation of pro-inflammatory cytokines in patient serum samples correlates with tryptase levels. Finally, MC-associated transcripts were elevated in human CML BM samples. Thus, our study identifies MCs as essential contributors to disease progression and suggests considering them as an additional target in CML therapy.Mast cells play a key role in the pro-inflammatory tumor microenvironment of the bone marrow. Shown is a cartoon summarizing our results from the mouse model. BCR::ABL1 transformed MCs, as part of the malignant clone, are essential for the elevation of pro-inflammatory cytokines, known to be important in disease initiation and progression.

Altered interictal serum histamine and immunoglobulin E but unchanged tryptase levels in individuals with episodic and chronic migraine

Serum histamine, immunoglobulin E, and tryptase are markers of allergic diseases. Despite the reported association between migraine and allergic diseases, differences in these marker levels between episodic and chronic migraines remain unelucidated. We investigated serum histamine, immunoglobulin E, and tryptase levels in 97 and 96 participants with episodic migraine and chronic migraine, respectively, and 56 controls according to the presence of allergic diseases. Serum histamine levels in episodic migraine (median and interquartile ranges, 0.78 [0.65-1.25] ng/mL, p < 0.001) and chronic migraine (0.89 [0.67-1.28] ng/mL, p < 0.001) participants were significantly lower than those in healthy controls (1.19 [0.81-2.08] ng/mL) among the 160 participants without allergic diseases. Serum immunoglobulin E levels in episodic migraine and chronic migraine participants with allergic diseases negatively correlated with headache frequency (correlation coefficient = -0.263, p = 0.017). Serum histamine levels in participants with allergic diseases and serum immunoglobulin E levels in participants without allergic diseases were not significantly different among episodic migraine, chronic migraine, and control groups. Serum tryptase levels did not significantly differ among episodic migraine, chronic migraine, and control participants with and without allergic diseases. Altered serum histamine and immunoglobulin E levels in episodic migraine and chronic migraine and different profiles concerning allergic diseases suggest the involvement of allergic mechanisms in migraine pathogenesis.

T-cell chronic active EBV diagnosed in a 65-year-old male presenting as idiopathic hypereosinophilic syndrome

A 65-year-old male from Nigeria, admitted with dehydration and painful oral ulcers, is seen by allergy/immunology for hypereosinophilia.The patient had idiopathic eosinophilia (mean 5,000 cells/uL) ongoing for nine years. There were no evident drug or infectious causes. The eosinophilia peaked at 28,000 cells/µL, accompanied by parotid swelling, pustular skin rash, and elevated serum-IgG4 level (400 mg/dL). Rheumatology evaluated for IgG4-related disease and hypereosinophilic syndrome. This work-up demonstrated elevated IgE (39,000 IU/mL) and tryptase (40 ng/mL) levels. Bone marrow biopsy showed a hypercellular marrow with erythroid hyperplasia and eosinophilia. Submandibular gland, skin, and excisional lymph node biopsies demonstrated IgGsecreting plasma cells, lymphocytic/eosinophilic infiltrates, and lymphoid hyperplasia, respectively. All biopsies stained negative for IgG4. Treatment for idiopathic hypereosinophilia was initiated with corticosteroids, rituximab, and mycophenolate mofetil (MMF). Symptomatic improvement was attained on MMF (1000 mg twice daily) with the addition of mepolizumab (300 mg every 4 weeks).He unfortunately progressed to high fevers with elevated ferritin (7,286 ug/L) and soluble IL-2Ra (31,276.7 pg/mL) levels. He did not meet full criteria for hemophagocytic lymphohistiocytosis and improved after corticosteroids. EBV PCR from blood was >220,000 IU/mL.Dedicated immune work-up showed a non-specific population of lymphocyte-like cells without clear lineage markers (CD2dim/- surface CD3-CD4-CD8-CD7-CD56-CD49d-CD294dim) on peripheral blood flow cytometry, with otherwise normal T, B, and NK cell enumeration. There was reduced cytotoxic killing function of CD8+ T cells and NK cells by chromium-51 release assay. Sorted peripheral blood mononuclear cells demonstrated positive EBV viral load in B cells (1,018,239 IU/mL), T cells (857,418 IU/mL),NK cells (237,459), and myeloid cells (532,641 IU/mL). EBV-encoded RNA was positive within lymph node T cells, most consistent with a diagnosis of T-cell CA-EBV. The Invitae 407 gene immunodeficiency panel was sent; however, a pathogenic variant was not identified. The patient was seen by hematology/oncology with plans for hematopoietic stem cell transplant. Unfortunately, he succumbed to complications from CA-EBV and multiorgan failure.We describe a male with lymphocytic-variant hypereosinophilic syndrome and a longstanding constellation of inflammatory and lymphoproliferative symptoms due to CA-EBV. His course initially eluded his care team and only after careful multidisciplinary discussion was a diagnosis reached.

Avapritinib for the Treatment of Indolent Systemic Mastocytosis

Indolent systemic mastocytosis (ISM) is a disorder characterized by an accumulation of mast cells in subdermal tissue that leads to exaggerated immune response after release of mast cells mediators. Routinely administered treatments include H1 and H2 receptor antagonists, mast cell stabilizers, corticosteroids, and more recently anti-IgE antibody therapies. Our case presentation explores the treatment of indolent mastocytosis with avapritinib, an antineoplastic, after routine treatment options failed.A 64-year-old female with history of obesity presented to a community-based Allergy/Immunology clinic with chief complaints of recurrent throat tightness, fatigue, headaches, brain fog. She was found to have high tryptase levels which remained persistently elevated from 46 to 55 (include units) over 13-month span. Physical exam was grossly unremarkable.Bone marrow biopsy showed mast cell aggregates highly suspicious for ISM. PCR for KIT (D816V) mutation was positive. Initial treatment included fexofenadine 180 mg and famotidine 20 mg both twice daily. Overall, she had less frequent episode of throat tightness over 9 months, but itchiness, fatigue, brain fog persisted. Monthlyomalizumab 300 mg was added on but was eventually discontinued to lack of benefit. She was referred to a tertiary center where avapritinib 25 mg daily was started. Four months after initiation, occurrences of throat tightness, stomach cramps, and vomiting resolved, and came off all other therapies for mastocytosis. Eight months after avapritinib initiation tryptase had decreased to 19.Avapritinib is a selective kinase inhibitor used to avoid resistance in patients undergoing chemotherapy with indications in those with advanced systemic mastocytosis and neoplastic complications. The mechanism of action of avapritinib includes inhibition of KIT and PDGFRA mutations. Treatment in our patient resulted in the successful symptomatic treatment of indolent systemic mastocytosis targeting KIT (D816V). This case demonstrates a new treatment which may improve the quality of life of individuals with ISM.

Genetically defined individual reference ranges for tryptase limit unnecessary procedures and unmask myeloid neoplasms.

Serum tryptase is a biomarker used to aid in the identification of certain myeloid neoplasms, most notably systemic mastocytosis, where basal serum tryptase (BST) levels>20ng/mL are a minor criterion for diagnosis. Although clonal myeloid neoplasms are rare, the common cause for elevated BST levels is the genetic trait hereditary α-tryptasemia (HαT) caused by increased germline TPSAB1 copy number. To date, the precise structural variation and mechanism(s) underlying elevated BST in HαT and the general clinical utility of tryptase genotyping, remain undefined. Through cloning, long-read sequencing, and assembling of the human tryptase locus from an individual with HαT, and validating our findings invitro and in silico, we demonstrate that BST elevations arise from overexpression of replicated TPSAB1 loci encoding canonical α-tryptase protein owing to coinheritance of a linked overactive promoter element. Modeling BST levels based on TPSAB1 replication number, we generate new individualized clinical reference values for the upper limit of normal. Using this personalized laboratory medicine approach, we demonstrate the clinical utility of tryptase genotyping, finding that in the absence of HαT, BST levels >11.4 ng/mL frequently identify indolent clonal mast cell disease. Moreover, substantial BST elevations (eg, >100 ng/mL), which would ordinarily prompt bone marrow biopsy, can result from TPSAB1 replications alone and thus be within normal limits for certain individuals with HαT.

Interpreting serum tryptase levels in cases of anaphylaxis and concomitant bacterial infection

Interpreting serum tryptase levels in cases of anaphylaxis and concomitant bacterial infection

E031 A rare case of diffuse osteosclerosis

Abstract Background/Aims Diffuse skeletal fluorosis is a common condition in countries with high content of fluoride in the ground water like India and China. Skeletal fluorosis in the UK is rare and presents with non-specific findings such as back pain, elevated ALP or bone sclerosis. We describe a case referred from haematology for investigation of osteosclerosis. Methods 74-year-old female presented to the emergency department on several occasions with recurrent abdominal pain, severe low back pain and swelling of her lower limbs. Her mobility had been reduced due to previous femoral nerve injury. Blood tests on admission showed mild macrocytic anaemia. Alkaline phosphatase, renal, liver function tests and electrolytes were within normal range. Furthermore, calcium, phosphate, vitamin D and parathyroid hormone levels were within normal limits. CT CAP was done and no obvious or sinister cause for abdominal pain was found. However, it showed diffuse bony sclerosis. Bone densitometry DXA scan results as follows: T-score of + 1.6 in the hip and +1.7 in the neck of femur, they were unable to scan the lumbar spine as the patient was unable to tolerate positioning for the scan. This confirmed relatively raised bone density for patient’s age despite having risk factors for osteoporosis like previous wrist fracture, strong family history of osteoporosis, early menopause following total hysterectomy at age 41, coeliac disease and multiple falls due to poor mobility. Results A bone marrow aspirate and trephine biopsy and immunophenotyping were carried out and did not demonstrate any evidence of myeloid or lymphoid neoplasm. The next line of investigations included an isotope bone scan and blood tests including serum tryptase, uric acid and fluoride levels. Fluoride level came back as 411 which is 8-times more than the normal value. Patient mentioned that she uses fluoride toothpaste and brushed her teeth at least 10-14 times/day. X-ray of the hands showed no evidence of periosteal reactions or sclerosis. We recommended that she use fluoride free toothpaste and referred her for a dental opinion. While there is no effective therapeutic agent to reduce fluoride levels, patient was encouraged to use fluoride free toothpaste and also consult with her dentist for further evaluation. Conclusion This case emphasises the need for a comprehensive history and maintaining a high index of suspicion of skeletal fluorosis when encountered with a patient with a high bone mineral density (BMD) score on the DXA scan or diffuse skeletal sclerosis. The increase in bone mineral density is thought to be related to fluoride’s enhanced osteoblastic activity. Disclosure S. Mohamed: None. A. Phillips: None. J. Thomas: None. D. Makkuni: None.

Expression of SARS-CoV-2 receptor angiotensin-converting enzyme 2 by activating protein-1 in human mast cells.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection activates mast cells and induces a cytokine storm, leading to severe Coronavirus disease in 2019 (COVID-19). SARS-CoV-2 employs angiotensin-converting enzyme 2 (ACE2) for cell entry. In the present study, the expression of ACE2 and its mechanism in activated mast cells were studied utilizing the human mast cell line, HMC-1 cells and it was elucidated whether dexamethasone used as a treatment for COVID-19 could regulate ACE2 expression. Here we documented for the first time that levels of ACE2 were increased by stimulation of phorbol 12-myristate 13-acetate and A23187 (PMACI) in HMC-1 cells. Increased levels of ACE2 were significantly diminished by treatment with Wortmannin, SP600125, SB203580, PD98059, or SR11302. The expression of ACE2 was most significantly reduced by the activating protein (AP)-1 inhibitor SR11302. PMACI stimulation enhanced the expression of the transcription factor AP-1 for ACE2. In addition, levels of transmembrane protease/serine subfamily member 2 (TMPRSS2) and tryptase were increased in PMACI-stimulated HMC-1 cells. However, dexamethasone significantly lowered levels of ACE2, TMPRSS2, and tryptase generated by PMACI. Treatment with dexamethasone also reduced activation of signaling molecules linked to ACE2 expression. According to these findings, levels of ACE2 were up-regulated through activation of AP-1 in mast cells, suggesting that suppressing ACE2 levels in mast cells would be a therapeutic approach to lessen the harm caused by COVID-19.

Skin and bones: systemic mastocytosis and bone.

We report the case of a 69-year-old female with systemic mastocytosis, diagnosed based on widespread pigmented papules and macules, elevated serum tryptase levels and confirmatory skin and bone marrow biopsy, on a background of osteoporosis. A CT demonstrated multiple sclerotic lesions within lumbar vertebral bodies, sacrum and ileum, with surrounding osteolysis but no obvious compression fractures. She was treated with the RANK-L inhibitor denosumab, resulting in significant bone mineral density gain over the following 5 years. However, her serum tryptase levels gradually increased during this period despite treatment with the multikinase inhibitor, midostaurin. It is thus conceivable that her rapid increase in bone mineral density may be partly contributed by a predominance of pro-osteoblastic mediators released by abnormal mast cells, suggestive of more advanced disease. This case highlights the complexities of systemic mastocytosis-related bone disease and the interplay of numerous mediators contributing to a phenotype of both increased bone resorption and formation. Systemic mastocytosis is a neoplastic disease of mast cells characterized by abnormal proliferation and accumulation in the skin and other organs. It is most frequently associated with the somatic gain-of-function KIT D816V mutation. Systemic mastocytosis should be suspected in patients presenting with not only cutaneous symptoms suggestive of mast cell degranulation such as anaphylaxis, flushing or urticaria but also unexplained osteoporosis and gastrointestinal and constitutional symptoms. The prevalence of osteoporosis in systemic mastocytosis is high. Mast cell activation leads to the secretion of numerous chemical mediators which either promote or inhibit osteoclastic and/or osteoblastic activity, with the balance usually in favour of increased bone resorption. However, in advanced diseases with high mast cell burden, mast-cell-derived cytokines and mediators may promote osteoblastic activity, leading to osteosclerosis and apparent increases in bone mineral density. Treatment of osteoporosis in systemic mastocytosis involves antiresorptive therapy with bisphosphonates and more recently, denosumab. There are limited data on the role of osteoanabolic agents.

What to expect from KIT D816 V mutation in peripheral blood according to serum tryptase levels?

What to expect from KIT D816 V mutation in peripheral blood according to serum tryptase levels?

LBA01-08 EFFICACY OF TARGETED MAST CELL INHIBITION THERAPY IN CHRONIC PROSTATITIS/CHRONIC PELVIC PAIN SYNDROME

You have accessJournal of UrologyCME1 Apr 2023LBA01-08 EFFICACY OF TARGETED MAST CELL INHIBITION THERAPY IN CHRONIC PROSTATITIS/CHRONIC PELVIC PAIN SYNDROME Praveen Thumbikat, Goutham Pattabiraman, Catherine Osborn, Stephen Murphy, and Anthony Schaeffer Praveen ThumbikatPraveen Thumbikat More articles by this author , Goutham PattabiramanGoutham Pattabiraman More articles by this author , Catherine OsbornCatherine Osborn More articles by this author , Stephen MurphyStephen Murphy More articles by this author , and Anthony SchaefferAnthony Schaeffer More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003360.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a component of urologic chronic pelvic pain syndrome (UCPPS) and affects men, leading to chronic pain in the pelvic region or genitalia that is often accompanied by increased urinary frequency and urgency as well as sexual dysfunction. CPPS has an estimated prevalence rate of 6-12% of the male population with most diagnoses between the ages of 35-45. We have previously demonstrated that mast cells can be critical mediators of both chronic pelvic pain and lower urinary tract symptoms (LUTS). In this pilot clinical study, we therefore sought to identify subtypes of CP/CPPS characterized by mast cell dysfunction and evaluate the therapeutic efficacy of functional mast cell targeting on mast cell tryptase levels as well as on symptoms of pain and voiding dysfunction. METHODS: Men with CP/CPPS were recruited and evaluated in an open label, interventional uncontrolled trial after therapy with cromolyn sodium and cetirizine hydrochloride. The primary endpoint was a change in mast cell tryptase concentrations after treatment while secondary endpoints were changes in the NIH-CPSI and AUA-SI. Isolated cells from post-prostatic massage urine were evaluated for immune changes using mRNA expression analysis. RESULTS: 31 patients with a diagnoses of Category III CP/CPPS were consented, 25 patients qualified and 20 completed the study after meeting a prespecified threshold for active tryptase in expressed prostatic secretions. After treatment with cromolyn sodium and cetirizine dihydrochloride for 3-weeks, active tryptase concentrations were significantly reduced from 49.03±14.05 ug/ml to 25.49±5.48 ug/ml (p<0.05). The NIH-CPSI total score was reduced with a mean difference of 5.2±1 along with reduction in the pain, urinary and quality of life sub scores (p<0.001). A reduction in the AUA-SI was observed following treatment (p<0.05). NanoString mRNA analysis of isolated cells revealed downregulation of immune related pathways including Th1 and Th17 T cell differentiation and TLR signaling. Marked reduction in CD45+ cells and specifically macrophages and neutrophil abundance was observed. CONCLUSIONS: This pilot study presents a method to identify CP/CPPS patients with mast cell dysfunction and target them for therapeutic intervention using a novel, safe combination therapeutic approach. The resulting subgroup of CP/CPPS patients were shown to have a therapeutic response as measured primarily by a reduction in mast cell tryptase, a potential surrogate biomarker and reduction in CP/CPPS symptoms. These pilot studies will form the basis for future randomized placebo-controlled studies to evaluate these agents as CP/CPPS therapies. Source of Funding: This work was supported by the National Institute of Diabetes and Digestive and Kidney (NIDDK) grant R01DK083609 to Praveen Thumbikat. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of this abstract © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1179 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Praveen Thumbikat More articles by this author Goutham Pattabiraman More articles by this author Catherine Osborn More articles by this author Stephen Murphy More articles by this author Anthony Schaeffer More articles by this author Expand All Advertisement PDF downloadLoading ...

Effect of a protease-activated receptor-2 antagonist (GB88) on inflammation-related loss of alveolar bone in periodontal disease.

Protease-activated receptor-2 (PAR2 ), a pro-inflammatory G-protein coupled receptor, has been associated with pathogenesis of periodontitis and the resulting bone loss caused by oral pathogens, including the keystone pathogen Porphyromonas gingivalis (P. gingivalis). We hypothesised that administration of a PAR2 antagonist, GB88, might prevent inflammation and subsequent alveolar bone resorption in a mouse model of periodontal disease. Periodontitis was induced in mice by oral inoculations with P. gingivalis for a total of eight times over 24 days. The infected mice were treated with either GB88 or vehicle for the duration of the trial. Following euthanasia on day 56, serum was collected and used for the detection of mast cell tryptase. The right maxillae were defleshed and stained with methylene blue to measure the exposed cementum in molar teeth. The left maxillae were prepared for cryosections followed by staining for tartrate-resistant acid phosphatase to identify osteoclasts or with toluidine blue to identify mast cells. Reverse transcription quantitative PCR (RT-qPCR) was used to quantify the expression of inflammatory cytokines in the gingival tissue. Supernatants of T-lymphocyte cultures isolated from the regional lymph nodes were assayed using a cytometric bead array to measure the Th1/Th2/Th17 cytokine levels. Measurement of the exposed cementum showed that GB88 reduced P. gingivalis-induced alveolar bone loss by up to 69%. GB88 also prevented the increase in osteoclast numbers observed in the infected mice. Serum tryptase levels were significantly elevated in both the infected groups, and not altered by treatment. RT-qPCR showed that GB88 prevented the upregulation of Il1b, Il6, Ifng and Cd11b. In T-lymphocyte supernatants, only IFNγ and IL-17A levels were increased in response to infection, but this was prevented by GB88 treatment. GB88 significantly reduced osteoclastic alveolar bone loss in mice infected with P. gingivalis, seemingly by preventing the upregulation of several inflammatory cytokines. PAR2 antagonism may be an effective treatment strategy for periodontal disease.

The Japanese Epidemiologic Study for Perioperative Anaphylaxis, a prospective nationwide study: allergen exposure, epidemiology, and diagnosis of anaphylaxis during general anaesthesia

BackgroundDiagnosis of perioperative anaphylaxis is often challenging. This study describes the utility of a newly developed tool for identifying patients with a high possibility of anaphylaxis, and aimed to investigate the frequency of anaphylaxis with each drug during the perioperative period in Japan. MethodsThis study included patients with anaphylaxis of Grade 2 or higher severity during general anaesthesia at 42 facilities across Japan in 2019 and 2020. We developed and adopted a unique objective evaluation tool yielding a composite score for diagnosing anaphylaxis, which includes the results of skin tests and basophil activation tests, and clinical scores for perioperative anaphylaxis. The number of cases using each drug and the total number of anaphylaxis cases were investigated to calculate the frequency of anaphylaxis. ResultsGeneral anaesthesia was performed in 218 936 cases, which included 55 patients with suspected perioperative anaphylaxis. The developed composite score diagnosed 43 of them with a high probability of anaphylaxis. The causative agent was identified in 32 cases. Plasma histamine levels showed high diagnostic accuracy for anaphylaxis. The top causative agents were rocuronium (10 cases in 210 852 patients, 0.005%), sugammadex (7 cases in 150 629 patients, 0.005%), and cefazolin (7 cases in 106 005 patients, 0.007%). ConclusionsWe developed a composite tool to diagnose anaphylaxis, and found that the combination of tryptase levels, skin testing, and basophil activation testing results and clinical score improved the certainty of anaphylaxis diagnosis. The incidence of perioperative anaphylaxis in our study was 1 in about 5000 general anaesthesia cases. Clinical trial registrationUMIN000035350.

Defining hereditary alpha-tryptasemia as a risk/modifying factor for anaphylaxis: are we there yet?

Hereditary α-tryptasemia (HαT) is a common autosomal dominant genetic trait with variable penetrance associated with increased serum baseline tryptase (SBT) levels. Clinical manifestations may range from an absence of symptoms to overtly severe and recurrent anaphylaxis. Symptoms have been claimed to result from excessive activation of EGF-like module-containing mucin-like hormone receptor-like 2 (EMR2) and protease-activated receptor 2 (PAR-2) receptors by α/β-tryptase heterotetramers. Herein, we aimed to review the evidence on whether HαT can be considered a hereditary risk factor or a modifying factor for anaphylaxis.Increased SBT levels have been linked to an increased risk of anaphylaxis. Likewise, recent studies have shown that HαT might be associated with a higher risk of developing anaphylaxis and more severe anaphylaxis. The same has also been shown for patients with clonal mast cell disorders, in whom the co-existence of HαT might lead to a greater propensity for severe, potentially life-threatening anaphylaxis. However, studies leading to such conclusions are generally limited in sample size, while other studies have shown opposing results. As such, further studies investigating the potential association of HαT with anaphylaxis caused by different triggers, and different severity grades, in both patients with clonal mast cell activation syndromes and the general population are still needed.

Ten-year outcomes of Perioperative Anaphylaxis Workup Study in Hong Kong (PAWS-HK): Performance of diagnostic modalities

BackgroundStudies on perioperative anaphylaxis (PA) in Asia are lacking. Furthermore, allergy workup for PA has largely been limited to the “silver standard” of skin tests (ST). Using in vitro tests as an adjunct to ST may improve and overcome these diagnostic challenges. ObjectiveTo evaluate the clinical characteristics and diagnostic tests of patients with suspected PA through the Perioperative Anaphylaxis Workup Study in Hong Kong cohort. MethodsPatients with a diagnosis of PA over a 10-year period were recruited into the Perioperative Anaphylaxis Workup Study in Hong Kong. We reviewed the medical records, tryptase elevation, and diagnostic tests including ST, specific immunoglobulin E, and basophil activation tests (BAT). ResultsIn 151 patients with PA, diagnosis was reached in three-fourths of the cases (113/151, 74.8%). The most common culprits identified were neuromuscular blocking agents (25.8%), β lactams (17.2%) and chlorhexidine (13.9%). Severe anaphylaxis was associated with female sex, older age, elevated acute tryptase levels, and more cardiovascular manifestations during induction. Skin tests remained the most sensitive diagnostic modality overall (66.2%). BAT showed better performance for chlorhexidine and gelofusine anaphylaxis, with sensitivity of 80.0% and 79.6%, respectively. Specific Immunoglobulin E indicated even higher sensitivity (95.2%) than did ST (85.0%) and BAT (80.0%) for chlorhexidine anaphylaxis but performed poorly for other drugs. ConclusionNeuromuscular blocking agents remain the most common culprit in PA. There was a higher prevalence of gelofusine anaphylaxis in our cohort than was seen in the literature. Skin tests remain the most sensitive testing modality. In vitro tests for chlorhexidine and gelofusine showed promising results, but more studies to further elucidate its use are warranted.

Proteomic and transcriptomic screening demonstrates increased mast cell–derived CCL23 in systemic mastocytosis

Systemic mastocytosis (SM) is a heterogeneous group of mast cell-driven diseases diagnosed by bone marrow sampling. However, there are a limited number of available blood disease biomarkers. Our aim was to identify mast cell-derived proteins that could potentially serve as blood biomarkers for indolent and advanced forms of SM. We performed a plasma proteomics screening coupled with single-cell transcriptomic analysis in SM patients and healthy subjects. Plasma proteomics screening identified 19 proteins upregulated in indolent disease compared to healthy, and 16 proteins in advanced disease compared to indolent. Among these, 5 proteins, CCL19, CCL23, CXCL13, IL-10, and IL-12Rβ1, were higher in indolent relative to healthy and in advanced disease compared to indolent. Single-cell RNA sequencing demonstrated that CCL23, IL-10, and IL-6 were selectively produced by mast cells. Notably, plasma CCL23 levels correlated positively with known markers of SM disease severity, namely tryptase levels, percentage bone marrow mast cell infiltration, and IL-6. CCL23 is produced predominantly by mast cellsin SM, and CCL23 plasma levels are associated withdisease severity, correlating positively with established markers ofdisease burden, thus suggesting that CCL23 is a specificSMbiomarker. In addition, the combination of CCL19, CCL23, CXCL13, IL-10, and IL-12Rβ1 may be useful fordefining disease stage.