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1.
Clin Transplant ; 38(5): e15312, 2024 May.
Article in English | MEDLINE | ID: mdl-38678586

ABSTRACT

INTRODUCTION: Solid organ transplantation (SOT) is a lifesaving treatment for end-stage organ failure. Although many factors affect the success of organ transplantation, recipient and donor sex are important biological factors influencing transplant outcome. However, the impact of the four possible recipient and donor sex combinations (RDSC) on transplant outcome remains largely unclear. METHODS: A scoping review was carried out focusing on studies examining the association between RDSC and outcomes (mortality, graft rejection, and infection) after heart, lung, liver, and kidney transplantation. All studies up to February 2023 were included. RESULTS: Multiple studies published between 1998 and 2022 show that RDSC is an important factor affecting the outcome after organ transplantation. Male recipients of SOT have a higher risk of mortality and graft failure than female recipients. Differences regarding the causes of death are observed. Female recipients on the other hand are more susceptible to infections after SOT. CONCLUSION: Differences in underlying illnesses as well as age, immunosuppressive therapy and underlying biological mechanisms among male and female SOT recipients affect the post-transplant outcome. However, the precise mechanisms influencing the interaction between RDSC and post-transplant outcome remain largely unclear. A better understanding of how to identify and modulate these factors may improve outcome, which is particularly important in light of the worldwide organ shortage. An analysis for differences of etiology and causes of graft loss or mortality, respectively, is warranted across the RDSC groups. PRACTITIONER POINTS: Recipient and donor sex combinations affect outcome after solid organ transplantation. While female recipients are more susceptible to infections after solid organ transplantation, they have higher overall survival following SOT, with causes of death differing from male recipients. Sex-differences should be taken into account in the post-transplant management.


Subject(s)
Organ Transplantation , Tissue Donors , Humans , Organ Transplantation/adverse effects , Organ Transplantation/mortality , Female , Male , Tissue Donors/supply & distribution , Prognosis , Graft Rejection/etiology , Graft Rejection/mortality , Sex Factors , Graft Survival , Transplant Recipients/statistics & numerical data , Risk Factors , Postoperative Complications
2.
Sci Rep ; 13(1): 16417, 2023 09 29.
Article in English | MEDLINE | ID: mdl-37775538

ABSTRACT

Polarimetry is an optical characterization technique capable of analyzing the polarization state of light reflected by materials and biological samples. In this study, we investigate the potential of Müller matrix polarimetry (MMP) to analyze fresh pancreatic tissue samples. Due to its highly heterogeneous appearance, pancreatic tissue type differentiation is a complex task. Furthermore, its challenging location in the body makes creating direct imaging difficult. However, accurate and reliable methods for diagnosing pancreatic diseases are critical for improving patient outcomes. To this end, we measured the Müller matrices of ex-vivo unfixed human pancreatic tissue and leverage the feature-learning capabilities of a machine-learning model to derive an optimized data representation that minimizes normal-abnormal classification error. We show experimentally that our approach accurately differentiates between normal and abnormal pancreatic tissue. This is, to our knowledge, the first study to use ex-vivo unfixed human pancreatic tissue combined with feature-learning from raw Müller matrix readings for this purpose.


Subject(s)
Diagnostic Imaging , Humans , Diagnostic Imaging/methods , Spectrum Analysis
3.
Allergy ; 78(7): 1980-1996, 2023 07.
Article in English | MEDLINE | ID: mdl-36883475

ABSTRACT

BACKGROUND: Allergy to peanut is one of the leading causes of anaphylactic reactions among food allergic patients. Immunization against peanut allergy with a safe and protective vaccine holds a promise to induce durable protection against anaphylaxis caused by exposure to peanut. A novel vaccine candidate (VLP Peanut), based on virus-like particles (VLPs), is described here for the treatment of peanut allergy. METHODS AND RESULTS: VLP Peanut consists of two proteins: a capsid subunit derived from Cucumber mosaic virus engineered with a universal T-cell epitope (CuMVTT ) and a CuMVTT subunit fused with peanut allergen Ara h 2 (CuMVTT -Ara h 2), forming mosaic VLPs. Immunizations with VLP Peanut in both naïve and peanut-sensitized mice resulted in a significant anti-Ara h 2 IgG response. Local and systemic protection induced by VLP Peanut were established in mouse models for peanut allergy following prophylactic, therapeutic, and passive immunizations. Inhibition of FcγRIIb function resulted in a loss of protection, confirming the crucial role of the receptor in conferring cross protection against peanut allergens other than Ara h 2. CONCLUSION: VLP Peanut can be delivered to peanut-sensitized mice without triggering allergic reactions, while remaining highly immunogenic and offering protection against all peanut allergens. In addition, vaccination ablates allergic symptoms upon allergen challenge. Moreover, the prophylactic immunization setting conferred the protection against subsequent peanut-induced anaphylaxis, showing the potential for preventive vaccination. This highlights the effectiveness of VLP Peanut as a prospective break-through immunotherapy vaccine candidate toward peanut allergy. VLP Peanut has now entered clinical development with the study PROTECT.


Subject(s)
Anaphylaxis , Peanut Hypersensitivity , Mice , Animals , Peanut Hypersensitivity/prevention & control , Prospective Studies , Antigens, Plant , Allergens , Arachis
4.
PLoS One ; 18(3): e0281822, 2023.
Article in English | MEDLINE | ID: mdl-36989207

ABSTRACT

Systemic AA-amyloidosis is a protein-misfolding disease characterized by fibril deposition of serum amyloid-A protein (SAA) in several organs in humans and many animal species. Fibril deposits originate from abnormally high serum levels of SAA during chronic inflammation. A high prevalence of AA-amyloidosis has been reported in captive cheetahs and a horizontal transmission has been proposed. In domestic cats, AA-amyloidosis has been mainly described in predisposed breeds but only rarely reported in domestic short-hair cats. Aims of the study were to determine AA-amyloidosis prevalence in dead shelter cats. Liver, kidney, spleen and bile were collected at death in cats from 3 shelters. AA-amyloidosis was scored. Shedding of amyloid fibrils was investigated with western blot in bile and scored. Descriptive statistics were calculated. In the three shelters investigated, prevalence of AA-amyloidosis was 57.1% (16/28 cats), 73.0% (19/26) and 52.0% (13/25), respectively. In 72.9% of cats (35 in total) three organs were affected concurrently. Histopathology and immunofluorescence of post-mortem extracted deposits identified SAA as the major protein source. The duration of stay in the shelters was positively associated with a histological score of AA-amyloidosis (B = 0.026, CI95% = 0.007-0.046; p = 0.010). AA-amyloidosis was very frequent in shelter cats. Presence of SAA fragments in bile secretions raises the possibility of fecal-oral transmission of the disease. In conclusion, AA-amyloidosis was very frequent in shelter cats and those staying longer had more deposits. The cat may represent a natural model of AA-amyloidosis.


Subject(s)
Acinonyx , Amyloidosis , Immunoglobulin Light-chain Amyloidosis , Humans , Cats , Animals , Amyloidosis/epidemiology , Amyloidosis/veterinary , Amyloid , Serum Amyloid A Protein/metabolism
5.
Front Immunol ; 14: 1339171, 2023.
Article in English | MEDLINE | ID: mdl-38274816

ABSTRACT

The rising global incidence of IgE-mediated allergic reactions poses a significant challenge to the quality of life of affected individuals and to healthcare systems, with current treatments being limited in effectiveness, safety, and disease-modifying capabilities. IgE acts by sensitizing the high-affinity IgE receptor FcεRI expressed by mast cells and basophils, tuning these cells for inflammatory degranulation in response to future allergen encounters. In recent years, IgG has emerged as an essential negative regulator of IgE-dependent allergic inflammation. Mechanistically, studies have proposed different pathways by which IgG can interfere with the activation of IgE-mediated inflammation. Here, we briefly summarize the major proposed mechanisms of action by which IgG controls the IgE-FcεRI inflammatory axis and how those mechanisms are currently applied as therapeutic interventions for IgE-mediated inflammation.


Subject(s)
Immunoglobulin E , Quality of Life , Humans , Immunoglobulin E/metabolism , Basophils/metabolism , Immunoglobulin G/metabolism , Inflammation/metabolism
6.
Liver Int ; 42(10): 2247-2259, 2022 10.
Article in English | MEDLINE | ID: mdl-35686702

ABSTRACT

BACKGROUND AND AIMS: Patients with cirrhotic refractory ascites ineligible for transjugular intrahepatic shunt (TIPSS) have limited treatment options apart from repeated large volume paracentesis. The alfapump® is an implantable device mobilizing ascites from the peritoneal cavity to the bladder, from where it can be excreted. The aim of this observational cohort study was to prospectively investigate safety and efficacy of the device in a real-world cohort with cirrhotic refractory ascites and contraindications for TIPSS. METHODS: A total of 106 patients received an implant at 12 European centres and were followed up for up to 24 months. Complications, device deficiencies, frequency of paracentesis, clinical status and survival were recorded prospectively. RESULTS: Approximately half of the patients died on-study, about a quarter was withdrawn because of serious adverse events leading to explant, a sixth were withdrawn because of liver transplant or recovery, and nine completed follow-up. The most frequent causes of on-study death and complication-related explant were progression of liver disease and infection. The device reduced the requirement for large-volume paracentesis significantly, with more than half of patients not having required any post-implant. Survival benefits were not observed. Device-related reinterventions were predominantly caused by device deficiencies. A post-hoc comparison of the first 50 versus the last 50 patients enrolled revealed a decreased reintervention rate in the latter, mainly related to peritoneal catheter modifications. CONCLUSIONS: The device reduced paracentesis frequency in a real-world setting. Technical complications were successfully decreased by optimization of management and device modification (NCT01532427).


Subject(s)
Liver Transplantation , Portasystemic Shunt, Transjugular Intrahepatic , Ascites/etiology , Ascites/therapy , Humans , Liver Cirrhosis , Liver Transplantation/adverse effects , Paracentesis/adverse effects , Portasystemic Shunt, Transjugular Intrahepatic/adverse effects , Portasystemic Shunt, Transjugular Intrahepatic/methods , Registries
7.
Molecules ; 27(12)2022 Jun 20.
Article in English | MEDLINE | ID: mdl-35745058

ABSTRACT

Ascites is a common complication of decompensated liver cirrhosis, and yet relatively little is known about its biochemical composition. We conducted two metabolomic investigations, comparing the profile of ascites from 33 cirrhotic patients and postoperative peritoneal drainage fluid from 33 surgical patients (Experiment 1). The profile of paired ascites and plasma was also compared in 17 cirrhotic patients (Experiment 2). Gas chromatography−mass spectrometry-based metabolomics identified 29 metabolites that significantly characterized ascites fluid, whether postoperative drainage fluid or plasma were used as controls. Ten elevated amino acids (glutamine, proline, histidine, tyrosine, glycine, valine, threonine, methionine, lysine, phenylalanine) and seven diminished lipids (laurate, myristate, palmitate, oleate, vaccenate, stearate, cholesterol) largely comprised the cirrhotic ascites metabolomic phenotype that differed significantly (adjusted p < 0.002 to 0.03) from peritoneal drainage fluid or plasma. The pattern of upregulated amino acids in cirrhotic ascites did not indicate albumin proteolysis by peritoneal bacteria. Bidirectional clustering showed that the more severe the cirrhosis, the lower the lipid concentration in ascitic fluid. The metabolomic compartment of ascites in patients with decompensated cirrhosis is characterized by increased amino acids and decreased lipids. These novel findings have potential relevance for diagnostic purposes.


Subject(s)
Ascites , Liver Cirrhosis , Amino Acids , Ascites/metabolism , Cholesterol , Humans , Liver Cirrhosis/metabolism , Metabolomics
8.
J Clin Monit Comput ; 36(4): 1109-1119, 2022 08.
Article in English | MEDLINE | ID: mdl-34247307

ABSTRACT

Numerous patient-related clinical parameters and treatment-specific variables have been identified as causing or contributing to the severity of peritonitis. We postulated that a combination of clinical and surgical markers and scoring systems would outperform each of these predictors in isolation. To investigate this hypothesis, we developed a multivariable model to examine whether survival outcome can reliably be predicted in peritonitis patients treated with open abdomen. This single-center retrospective analysis used univariable and multivariable logistic regression modeling in combination with repeated random sub-sampling validation to examine the predictive capabilities of domain-specific predictors (i.e., demography, physiology, surgery). We analyzed data of 1,351 consecutive adult patients (55.7% male) who underwent open abdominal surgery in the study period (January 1998 to December 2018). Core variables included demographics, clinical scores, surgical indices and indicators of organ dysfunction, peritonitis index, incision type, fascia closure, wound healing, and fascial dehiscence. Postoperative complications were also added when available. A multidomain peritonitis prediction model (MPPM) was constructed to bridge the mortality predictions from individual domains (demographic, physiological and surgical). The MPPM is based on data of n = 597 patients, features high predictive capabilities (area under the receiver operating curve: 0.87 (0.85 to 0.90, 95% CI)) and is well calibrated. The surgical predictor "skin closure" was found to be the most important predictor of survival in our cohort, closely followed by the two physiological predictors SAPS-II and MPI. Marginal effects plots highlight the effect of individual outcomes on the prediction of survival outcome in patients undergoing staged laparotomies for treatment of peritonitis. Although most single indices exhibited moderate performance, we observed that the predictive performance was markedly increased when an integrative prediction model was applied. Our proposed MPPM integrative prediction model may outperform the predictive power of current models.


Subject(s)
Open Abdomen Techniques , Peritonitis , Abdomen/surgery , Adult , Female , Humans , Laparotomy , Male , Peritonitis/surgery , Retrospective Studies
9.
Ther Umsch ; 78(10): 615-621, 2021.
Article in German | MEDLINE | ID: mdl-34844434

ABSTRACT

Neuroendocrine tumor of the pancreas: What is new? Abstract. Neuroendocrine neoplasms are a rare and heterogeneous group of tumors with very different clinical presentations. Accordingly, they are initially difficult to recognize in clinical practice and diagnosis is often delayed. The necessary diagnostic steps include radiological and functional / nuclear medicine examinations to determine the extent of the primary tumor on the one hand and the presence of metastases on the other. If indicated, tissue sampling / biopsy is indicated. The resulting treatments include surgical resection, treatment with somatostatin analogues or multimodal therapy concepts, depending on the type and spread of the tumor and the symptoms. The therapy of patients with NET must be discussed at an interdisciplinary tumor board at a specialized center.


Subject(s)
Neuroendocrine Tumors , Pancreatic Neoplasms , Combined Modality Therapy , Humans , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/therapy , Pancreas , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/therapy
10.
J Allergy Clin Immunol ; 147(4): 1430-1441, 2021 04.
Article in English | MEDLINE | ID: mdl-33309740

ABSTRACT

BACKGROUND: IgE causes anaphylaxis in type I hypersensitivity diseases by activating degranulation of effector cells such as mast cells and basophils. The mechanisms that control IgE activity and prevent anaphylaxis under normal conditions are still enigmatic. OBJECTIVE: We aimed to unravel how anti-IgE autoantibodies are induced and we aimed to understand their role in regulating serum IgE level and allergic anaphylaxis. METHODS: We immunized mice with different forms of IgE and tested anti-IgE autoantibody responses and their specificities. We then analyzed the effect of those antibodies on serum kinetics and their in vitro and in vivo impact on anaphylaxis. Finally, we investigated anti-IgE autoantibodies in human sera. RESULTS: Immunization of mice with IgE-immune complexes induced glycan-specific anti-IgE autoantibodies. The anti-IgE autoantibodies prevented effector cell sensitization, reduced total IgE serum levels, protected mice from passive and active IgE sensitization, and resulted in cross-protection against different allergens. Furthermore, glycan-specific anti-IgE autoantibodies were present in sera from subjects with allergy and subjects without allergy. CONCLUSION: In conclusion, this study provided the first evidence that in the murine model, the serum level and anaphylactic activity of IgE may be downregulated by glycan-specific IgG anti-IgE autoantibodies.


Subject(s)
Antibodies, Anti-Idiotypic/immunology , Autoantibodies/immunology , Hypersensitivity/immunology , Immunoglobulin G/immunology , Polysaccharides/immunology , Allergens/administration & dosage , Animals , Disease Models, Animal , Glycoproteins/administration & dosage , Humans , Immunoglobulin E/administration & dosage , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout
11.
Nat Metab ; 2(8): 688-702, 2020 08.
Article in English | MEDLINE | ID: mdl-32694825

ABSTRACT

Adipose tissue eosinophils (ATEs) are important in the control of obesity-associated inflammation and metabolic disease. However, the way in which ageing impacts the regulatory role of ATEs remains unknown. Here, we show that ATEs undergo major age-related changes in distribution and function associated with impaired adipose tissue homeostasis and systemic low-grade inflammation in both humans and mice. We find that exposure to a young systemic environment partially restores ATE distribution in aged parabionts and reduces adipose tissue inflammation. Approaches to restore ATE distribution using adoptive transfer of eosinophils from young mice into aged recipients proved sufficient to dampen age-related local and systemic low-grade inflammation. Importantly, restoration of a youthful systemic milieu by means of eosinophil transfers resulted in systemic rejuvenation of the aged host, manifesting in improved physical and immune fitness that was partially mediated by eosinophil-derived IL-4. Together, these findings support a critical function of adipose tissue as a source of pro-ageing factors and uncover a new role of eosinophils in promoting healthy ageing by sustaining adipose tissue homeostasis.


Subject(s)
Adipose Tissue/physiology , Eosinophils/physiology , Immunity , Inflammation/pathology , Physical Fitness/physiology , Adipose Tissue/pathology , Adipose Tissue, White/pathology , Adipose Tissue, White/physiology , Adult , Aged , Aging , Animals , Eosinophils/immunology , Eosinophils/pathology , Gene Expression Regulation , Glucose Tolerance Test , Homeostasis , Humans , Interleukin-4/immunology , Interleukin-4/physiology , Mice , Mice, Inbred C57BL , Middle Aged , Muscle Strength , Satellite Cells, Skeletal Muscle/metabolism , Young Adult
12.
Vaccines (Basel) ; 8(1)2020 Mar 02.
Article in English | MEDLINE | ID: mdl-32131431

ABSTRACT

Type 2 diabetes mellitus (T2DM) is a chronic progressive disease characterized by insulin resistance and insufficient insulin secretion to maintain normoglycemia. The majority of T2DM patients bear amyloid deposits mainly composed of islet amyloid polypeptide (IAPP) in their pancreatic islets. These-originally ß-cell secretory products-extracellular aggregates are cytotoxic for insulin-producing ß-cells and are associated with ß-cell loss and inflammation in T2DM advanced stages. Due to the absence of T2DM preventive medicaments and the presence of only symptomatic drugs acting towards increasing hormone secretion and action, we aimed at establishing a novel disease-modifying therapy targeting the cytotoxic IAPP deposits in order to prevent the development of T2DM. We generated a vaccine based on virus-like particles (VLPs), devoid of genomic material, coupled to IAPP peptides inducing specific antibodies against aggregated, but not monomeric IAPP. Using a mouse model of islet amyloidosis, we demonstrate in vivo that our vaccine induced a potent antibody response against aggregated, but not soluble IAPP, strikingly preventing IAPP depositions, delaying onset of hyperglycemia and the induction of the associated pro-inflammatory cytokine Interleukin 1ß (IL-1ß). We offer the first cost-effective and safe disease-modifying approach targeting islet dysfunction in T2DM, preventing pathogenic aggregates without disturbing physiological IAPP function.

13.
Int Arch Allergy Immunol ; 181(5): 334-341, 2020.
Article in English | MEDLINE | ID: mdl-32155619

ABSTRACT

BACKGROUND: Peanut allergy is the most prevalent and dangerous food allergy. Peanuts consist of a large number of different allergens and peanut-allergic patients are frequently sensitized to multiple allergens. Hence, conventional desensitization approaches aim at targeting as many allergens as possible. METHODS: The monoclonal anti-Ara h 2 antibody (mAb) was produced by hybridoma cells derived from WT BALB/c mice after immunization with a vaccine based on virus-like particles coupled to Ara h 2. BALB/c mice were sensitized intraperitoneally with peanut extract absorbed to alum and mAbs were applied i.v. Challenge was performed the next day with the whole peanut extract intravenously and via skin prick test. RESULTS: Here we show in peanut-allergic mice that a single high-affinity mAb specific for Ara h 2 is able to block systemic and local allergic reactions induced by the complex peanut extract. We confirm in vitro binding of the mAb to the inhibitory low-affinity FcγRIIb receptor using a sensitive biosensor and demonstrate in vivo that protection was dependent on FcγRIIb. CONCLUSION: A single mAb specific for Ara h 2 is able to improve local and systemic allergic symptoms induced by the whole allergen mixture.


Subject(s)
2S Albumins, Plant/immunology , Antibodies, Monoclonal/immunology , Antigens, Plant/immunology , Peanut Hypersensitivity/immunology , Animals , Antibody Affinity , Female , Immunization , Mice , Mice, Inbred BALB C
14.
Article in English | MEDLINE | ID: mdl-35402957

ABSTRACT

Goal: Non-anatomical resections of liver tumors can be very challenging as the surgeon cannot use anatomical landmarks on the liver surface or in the ultrasound image for guidance. This makes it difficult to achieve negative resection margins (R0) and still preserve as much healthy liver tissue as possible. Even though image-guided surgery systems have been introduced to overcome this challenge, they are still rarely used due to their inaccuracy, time-effort and complexity in usage and setup. Methods: We have developed a novel approach, which allows us to create an intra-operative resection plan using navigated ultrasound. First, the surface is scanned using a navigated ultrasound, followed by tumor segmentation on a midsection ultrasound image. Based on this information, the navigation system calculates an optimal resection strategy and displays it along with the tracked surgical instruments. In this study, this approach was evaluated by three experienced hepatobiliary surgeons on ex-vivo porcine models. Results: Using this technique, an R0 resection could be achieved in 22 out of 23 (95.7% R0 resection rate) cases with a median resection margin of 5.9 mm (IQR 3.5-7.7 mm). The resection margin between operators 1, 2 and 3 was 7.8 mm, 4.15 mm and 5.1 mm respectively (p = 0.054). Conclusions: This approach could represent a useful tool for intra-operative guidance in non-anatomical resection alongside conventional ultrasound guidance. However, instructions and training are essential especially if the operator has not used an image-guidance system before.

15.
J Allergy Clin Immunol ; 145(4): 1240-1253.e3, 2020 04.
Article in English | MEDLINE | ID: mdl-31866435

ABSTRACT

BACKGROUND: Peanut allergy is a severe and increasingly frequent disease with high medical, psychosocial, and economic burden for affected patients and wider society. A causal, safe, and effective therapy is not yet available. OBJECTIVE: We sought to develop an immunogenic, protective, and nonreactogenic vaccine candidate against peanut allergy based on virus-like particles (VLPs) coupled to single peanut allergens. METHODS: To generate vaccine candidates, extracts of roasted peanut (Ara R) or the single allergens Ara h 1 or Ara h 2 were coupled to immunologically optimized Cucumber Mosaic Virus-derived VLPs (CuMVtt). BALB/c mice were sensitized intraperitoneally with peanut extract absorbed to alum. Immunotherapy consisted of a single subcutaneous injection of CuMVtt coupled to Ara R, Ara h 1, or Ara h 2. RESULTS: The vaccines CuMVtt-Ara R, CuMVtt-Ara h 1, and CuMVtt-Ara h 2 protected peanut-sensitized mice against anaphylaxis after intravenous challenge with the whole peanut extract. Vaccines did not cause allergic reactions in sensitized mice. CuMVtt-Ara h 1 was able to induce specific IgG antibodies, diminished local reactions after skin prick tests, and reduced the infiltration of the gastrointestinal tract by eosinophils and mast cells after oral challenge with peanut. The ability of CuMVtt-Ara h 1 to protect against challenge with the whole extract was mediated by IgG, as shown via passive IgG transfer. FcγRIIb was required for protection, indicating that immune complexes with single allergens were able to block the allergic response against the whole extract, consisting of a complex allergen mixture. CONCLUSIONS: Our data suggest that vaccination using single peanut allergens displayed on CuMVtt may represent a novel therapy against peanut allergy with a favorable safety profile.


Subject(s)
Antigens, Plant/genetics , Desensitization, Immunologic/methods , Membrane Proteins/genetics , Peanut Hypersensitivity/therapy , Plant Proteins/genetics , Vaccines/genetics , Virion/genetics , Animals , Antigens, Plant/immunology , Arachis/genetics , Cucumovirus/genetics , Genetic Engineering , Humans , Immunodominant Epitopes/immunology , Immunoglobulin E/metabolism , Membrane Proteins/immunology , Mice , Mice, Inbred BALB C , Plant Proteins/immunology , Receptors, IgG/metabolism , Vaccines/immunology , Virion/immunology
16.
Diseases ; 6(4)2018 Nov 21.
Article in English | MEDLINE | ID: mdl-30469323

ABSTRACT

Vaccination remains the most effective and essential prophylactic tool against infectious diseases. Enormous efforts have been made to develop effective vaccines against malaria but successes remain so far limited. Novel adjuvants may offer a significant advantage in the development of malaria vaccines, in particular if combined with inherently immunogenic platforms, such as virus-like particles (VLP). Dioleoyl phosphatidylserine (DOPS), which is expressed on the outer surface of apoptotic cells, represents a novel adjuvant candidate that may confer significant advantage over existing adjuvants, such as alum. In the current study we assessed the potential of DOPS to serve as an adjuvant in the development of a vaccine against malaria either alone or combined with VLP using Plasmodium falciparum thrombospondin-related adhesive protein (TRAP) as a target antigen. TRAP was chemically coupled to VLPs derived from the cucumber mosaic virus fused to a universal T cell epitope of tetanus toxin (CuMVtt). Mice were immunized with TRAP alone or formulated in alum or DOPS and compared to TRAP coupled to CuMVtt formulated in PBS or DOPS. Induced immune responses, in particular T cell responses, were assessed as the major protective effector cell population induced by TRAP. The protective capacity of the various formulations was assessed using a transgenic Plasmodium berghei expressing PfTRAP. All vaccine formulations using adjuvants and/or VLP increased humoral and T cell immunogenicity for PfTRAP compared to the antigen alone. Display on VLPs, in particular if formulated with DOPS, induced the strongest and most protective immune response. Thus, the combination of VLP with DOPS may harness properties of both immunogenic components and optimally enhance induction of protective immune responses.

18.
Surg Oncol ; 27(1): 100-105, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29549896

ABSTRACT

BACKGROUND: The 8th edition of the AJCC TNM staging system presents for the first time a specific classification for esophageal carcinomas treated with neoadjuvant therapy (yTNM8). In this single center study, we applied the novel staging system in a "real life" case series and compared the prognostic value of yTNM8 with the preceding 7th edition (TNM7). METHODS: Out of 272 consecutive esophageal carcinomas that were treated during a 15-year period in one surgical center, all 198 cases that had undergone neoadjuvant therapy were reviewed and classified according to TNM7 and yTNM8. RESULTS: 50 ypT0 cases that had no specific staging in TNM7 were included into stages I (ypT0N0M0; n = 42), IIIA (ypT0N1M0; n = 6), IVA (ypT0N3M0; n = 1) and IVB (ypT0N0M1; n = 1) in yTNM8. Both systems showed significant prognostic impact (p < 0.0001 each). yTNM8 was superior regarding prognostication with lower values for goodness-of-fit criteria (Akaike Information Criterion 1589.331 vs 1593.239; and Schwarz Bayesian Criterion 1605.487 vs.1619.088). However, in TNM7, stage IIB tumors had better prognosis than stage IIA tumors, and likewise, stage IIIA tumors better compared to stage II in yTNM8. CONCLUSIONS: yTNM8 allows accurate staging of esophageal carcinomas treated by neoadjuvant therapy, with slightly improved prognostication compared to TNM7. Additional data acquisition will be necessary for further improvement of staging for esophageal carcinomas after neoadjuvant treatment.


Subject(s)
Adenocarcinoma/pathology , Carcinoma, Squamous Cell/pathology , Esophageal Neoplasms/pathology , Esophagectomy , Neoplasm Staging/standards , Adenocarcinoma/surgery , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/surgery , Cohort Studies , Esophageal Neoplasms/surgery , Female , Follow-Up Studies , Humans , Male , Middle Aged , Survival Rate
19.
J Allergy Clin Immunol ; 142(5): 1529-1536.e6, 2018 11.
Article in English | MEDLINE | ID: mdl-29391255

ABSTRACT

BACKGROUND: Induction of allergen-specific IgG antibodies is a critical parameter for successful allergen-specific immunotherapy. IgG antibodies can inhibit IgE-mediated mast cell activation through direct allergen neutralization or through the inhibitory receptor FcγRIIb. The affinity of IgE antibodies to the allergen has been shown to be critical for cellular activation. OBJECTIVE: Here we addressed the question of affinity thresholds of allergen-specific IgG antibodies for inhibition of mast cell activation using 2 different mAbs against the major cat allergen Fel d 1 both in vitro and in vivo in mice. METHODS: Sequences of the 2 high-affinity mAbs were back-mutated to germline, resulting in low-affinity (10-7 mol/L) antibodies of the exact same specificity. RESULTS: Using these newly generated recombinant antibodies, we demonstrate that low-affinity antibodies are still able to inhibit mast cell activation through FcγRIIb but do not neutralize the allergen. CONCLUSION: Antibody affinity dictates the mechanism of mast cell inhibition, and IgG antibodies triggering the inhibitory FcγRIIb pathway can show a broader cross-reactivity pattern than previously thought. This indicates that allergen-specific immunotherapy generates a larger protective umbrella of inhibitory IgG antibodies than previously appreciated.


Subject(s)
Allergens/immunology , Antibodies, Monoclonal/immunology , Glycoproteins/immunology , Immunoglobulin G/immunology , Mast Cells/immunology , Receptors, IgG/immunology , Animals , Desensitization, Immunologic , Female , Mice, Inbred BALB C
20.
NPJ Vaccines ; 2: 30, 2017.
Article in English | MEDLINE | ID: mdl-29263885

ABSTRACT

Monoclonal antibodies are widely used to treat non-infectious conditions but are costly. Vaccines could offer a cost-effective alternative but have been limited by sub-optimal T-cell stimulation and/or weak vaccine responses in recipients, for example, in elderly patients. We have previously shown that the repetitive structure of virus-like-particles (VLPs) can effectively bypass self-tolerance in therapeutic vaccines. Their efficacy could be increased even further by the incorporation of an epitope stimulating T cell help. However, the self-assembly and stability of VLPs from envelope monomer proteins is sensitive to geometry, rendering the incorporation of foreign epitopes difficult. We here show that it is possible to engineer VLPs derived from a non human-pathogenic plant virus to incorporate a powerful T-cell-stimulatory epitope derived from Tetanus toxoid. These VLPs (termed CMVTT) retain self-assembly as well as long-term stability. Since Th cell memory to Tetanus is near universal in humans, CMVTT-based vaccines can deliver robust antibody-responses even under limiting conditions. By way of proof of concept, we tested a range of such vaccines against chronic inflammatory conditions (model: psoriasis, antigen: interleukin-17), neurodegenerative (Alzheimer's, ß-amyloid), and allergic disease (cat allergy, Fel-d1), respectively. Vaccine responses were uniformly strong, selective, efficient in vivo, observed even in old mice, and employing low vaccine doses. In addition, randomly ascertained human blood cells were reactive to CMVTT-VLPs, confirming recognition of the incorporated Tetanus epitope. The CMVTT-VLP platform is adaptable to almost any antigen and its features and performance are ideally suited for the design of vaccines delivering enhanced responsiveness in aging populations.

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