BNT162b2 Booster Vaccination Elicits Cross-Reactive Immunity Against SARS-CoV-2 Variants B.1.1.529 and B.1.617.2 in Convalescents of All Ages.

In this prospective observational cohort study we analyzed cellular and serological immune response parameters against SARS-CoV-2 and current variants of concern (VOC) in 147 COVID-19-convalescent and 39 COVID-19-naïve individuals before and after BNT162b2 booster vaccination. No significant differences regarding immunological response parameters were observed between younger and older individuals. Booster vaccination induced full recovery of both cellular and serological response parameters including IFN-γ secretion and anti-spike antibody titers with strong neutralization capacities against wild type SARS-COV-2 and Delta. Surprisingly, even serological neutralization capacity against Omicron was detectable one month after second vaccination and four months before it had been first observed in South Africa. As a result, more than 90% of convalescent individuals exhibited detectable and 75% strong Omicron neutralization capacity after booster vaccination, compared with 72% and 46% of COVID-19-naïve individuals. Our results support the notion that broad and cross-reactive immune memory against SARS-CoV-2 including currently known VOCs can be established by booster vaccination with spike-based mRNA vaccines like BNT162b2, particularly in COVID-19-convalescent individuals of all ages. Nevertheless, especially in COVID-19-naïve individuals future variants escaping the memory immune response may require vaccine approaches such as inactivated whole virus vaccines, which include all antigenic components of the virus.

BNT162b2 Vaccination Elicits Strong Serological Immune Responses Against SARS-CoV-2 Including Variants of Concern in Elderly Convalescents.

Elderly residents of long-term care facilities (LTCFs) have long been underrepresented in studies on vaccine efficacy, particularly in light of currently emerging variants of concern (VOCs). In this prospective observational cohort study, we analyzed serological immune responses in 190 individuals before, 3 weeks after 1st and 3 weeks after 2nd vaccination with BNT162b2. Unvaccinated COVID-19-convalescent subjects served as reference. End points comprised serum anti-spike IgG and IgA titers as well as neutralization capacities against unmutated and mutated SARS-CoV-2 receptor binding domains including B.1.1.7, B.1.351 and P.1. We found that antibody titers and neutralization capacities up to 3 weeks after 2nd vaccination with BNT162b2 were significantly higher in COVID-19-convalescent as compared to COVID-19-naive vaccinees. Moreover, pre-vaccination anti-NCP IgG titers, but not age or gender, had a high impact on the strength and kinetics of post-vaccination neutralization capacity development. Most importantly, BNT162b2-induced neutralization capacity was cross-reactive with VOCs. In contrast to unvaccinated convalescents, vaccinated convalescent individuals of all ages acquired strong neutralizing capacities against current VOCs. The present study suggests that COVID-19-convalescent individuals with a broad age range between 18 and 98 years benefit from BNT162b2 vaccination by developing strong and broad neutralizing immune responses against SARS-CoV-2 including current VOCs.

mRNA Vaccines Enhance Neutralizing Immunity against SARS-CoV-2 Variants in Convalescent and ChAdOx1-Primed Subjects.

To identify the most efficient methods of immunological protection against SARS-CoV-2, including the currently most widespread variants of concern (VOCs)-B.1.1.7, B.1.351 and P.1-a simultaneous side-by-side-comparison of available vaccination regimes is required. In this observational cohort study, we compared immunological responses in 144 individuals vaccinated with the mRNA vaccines BNT162b2 or mRNA-1273 and the vector vaccine ChAdOx1-nCoV-19, either alone, in combination, or in the context of COVID-19-convalescence. Unvaccinated COVID-19-convalescent subjects served as a reference. We found that cellular and serological immune responses, including neutralizing capacity against VOCs, were significantly stronger with mRNA vaccines as compared with COVID-19-convalescent individuals or vaccinated individuals receiving the vector vaccine ChAdOx1-nCoV-19. Booster immunizations with mRNA vaccines triggered strong and broadly neutralizing antibody and IFN-γ responses in 100% of vaccinated individuals investigated. This effect was particularly strong in COVID-19-convalescent and ChAdOx1-nCoV-19-primed individuals, who were characterized by comparably moderate cellular and neutralizing antibody responses before mRNA vaccine booster. Heterologous vaccination regimes and convalescent booster regimes using mRNA vaccines may allow enhanced protection against SARS-CoV-2, including current VOCs. Furthermore, such regimes may facilitate rapid (re-)qualification of convalescent plasma donors with high titers of broadly neutralizing antibodies.

[Development and implementation of an outpatient clinic at an initial reception centre for asylum seekers in the German federal state of Baden-Wuerttemberg]. / Entwicklung und Implementierung einer Medizinischen Ambulanz in einer Erstaufnahmeeinrichtung für Asylsuchende des Landes Baden-Württemberg.

In 2015, more than 890,000 asylum seekers were registered in Germany. The provision of medical and psychosocial care for asylum seekers is facing numerous obstacles. Access to health care is mostly insufficient, particularly in initial reception centres. The present article describes the development and implementation of an interdisciplinary outpatient clinic for asylum seekers at the main registration authority in the state of Baden-Wuerttemberg operated by physicians of the University Hospital of Heidelberg and the local Medical Association in Heidelberg. A steering committee was appointed to plan and implement the interdisciplinary outpatient clinic. Semi-structured interviews with nine steering committee members were conducted to elucidate perceived barriers during the planning and implementation phase. The steering committee's strong personal commitment and the health authorities' impartial management were cited as the main contributing factors to the success of the implementation process. Significant barriers were seen in the funding of personnel, equipment, and language mediation as well as in legal liability and billing-related aspects. Results are discussed with a focus on financing, administrative and legal framework as well as language mediation, documentation and further matters that are essential to ensure high-quality care.

Phosphorylation and turnover of paxillin in focal contacts is controlled by force and defines the dynamic state of the adhesion site.

Micro-environmental clues are critical to cell behavior. One of the key elements of migration is the generation and response to forces. Up to now there is no definitive concept on how the generation and responses to cellular forces influence cell behavior. Here, we show that phosphorylation of paxillin is a crucial event in the response to exogenous forces. Application of force induced growth of adhesion sites and this phenomenon was accompanied by a downregulation of Src family kinase activity, which in turn led to a decrease in the phosphorylation of paxillin at the tyrosine residues Y31 and Y118. The force-dependent growth of adhesion sites is mediated by a decrease in the turnover-rate of paxillin in focal contacts. This turnover critically depended on the phosphorylation state of paxillin at Y31/118. Paxillin is an important regulator in the control of the aggregate state of the whole adhesion site since the turnover of other adhesion site proteins such as vinculin is influenced by the phosphorylation state of paxillin as well. Taken together these data suggest that SFK dependent phosphorylation of paxillin is a crucial event in the regulation of adhesion site function in response to force.

Hepatocytes contribute to immune regulation in the liver by activation of the Notch signaling pathway in T cells.

The "liver tolerance effect" has been attributed to a unique potential of liver-resident nonprofessional APCs including hepatocytes (HCs) to suppress T cell responses. The exact molecular mechanism of T cell suppression by liver APCs is still largely unknown. In mice, IL-10-dependent T cell suppression is observed after Th1-mediated hepatitis induced by Con A. In this study, we show that HCs, particularly those from regenerating livers of Con A-pretreated mice, induced a regulatory phenotype in naive CD4(+) T cells in vitro. Using reporter mice, we observed that these T regulatory cells released substantial amounts of IL-10, produced IFN-γ, failed to express Foxp3, but suppressed proliferation of responder T cells upon restimulation with anti-CD3 mAb. Hence, these regulatory cells feature a similar phenotype as the recently described IL-10-producing Th1 cells, which are generated upon activation of Notch signaling. Indeed, inhibition of γ-secretase and a disintegrin and metalloproteinase 17 but not a disintegrin and metalloproteinase 10, respectively, which blocked Notch activation, prevented IL-10 secretion. HCs from Con A-pretreated mice showed enhanced expression of the Notch ligand Jagged1 and significantly increased receptor density of Notch1 on CD4(+) T cells. However, HCs from Con A-pretreated IFN regulatory factor 1(-/-) mice, which cannot respond to IFN-γ, as well as those from IFN-γ(-/-) mice failed to augment IL-10 production by CD4(+) T cells. In conclusion, it seems that HCs fine-tune liver inflammation by upregulation of Jagged1 and activation of Notch signaling in Th1 cells. This mechanism might be of particular importance in the regenerating liver subsequent to Th1-mediated hepatitis.

The phosphatase of regenerating liver 3 (PRL-3) promotes cell migration through Arf-activity-dependent stimulation of integrin α5 recycling.

The formation of metastasis is one of the most critical problems in oncology. The phosphatase of regenerating liver 3 (PRL-3) is a new target in colorectal cancer, mediating metastatic behavior through a promigratory function. However, detailed explanations for this effect have remained elusive. Here we show that PRL-3 interacts with the ADP-ribosylation factor 1 (Arf1). PRL-3 colocalizes with Arf1 in an endosomal compartment and associates with transmembrane proteins such as the transferrin receptor and α5 integrins. PRL-3 interacts with Arf1 through a distinct motif and regulates activation of Arf1. PRL-3-mediated migration depends on expression and activation of Arf1 and is sensitive to treatment with Brefeldin A. We also demonstrate that PRL-3 modulates recycling of α5 integrins and that its phosphatase activity as well as Arf activation and compartmentalization with Arf1 are required for this effect. In summary our data identify a new function for PRL-3 and show that Arf1 is a new PRL-3-dependent mediator of enhanced migration of cancer cells through enhanced recycling of matrix receptors.

Hepcidin is localised in gastric parietal cells, regulates acid secretion and is induced by Helicobacter pylori infection.

BACKGROUNDS AND AIMS: Hepcidin is an antimicrobial peptide and the central regulator of iron metabolism. Given that hepcidin was shown to be expressed in a variety of extrahepatic tissues and that stomach plays a role in iron absorption and in defence against infections, this study analysed the importance of hepcidin in the stomach. METHODS: Expression and localisation of gastric hepcidin was studied by quantitative RT-PCR, western blot, immunofluorescence and in situ hybridisation. Regulation of gastric hepcidin expression was analysed both in vitro and in vivo. Hepcidin wild-type (WT) and knockout (KO) animals were used to determine the impact of hepcidin on gastric bacterial overgrowth as well as gastric acid secretion. RESULTS: Hepcidin was abundantly expressed in the gastric fundus and corpus of all tested species. Treatment of AGS cells with ferric nitrilotriacetate solution downregulated hepcidin expression levels, while desferroxamine, interleukin 6 and Helicobacter pylori infection upregulated it. In humans, gastric hepcidin expression was elevated during H pylori infection and normalised after successful eradication. Gastric hepcidin is localised in parietal cells that are indispensable for gastric acid secretion. Comparisons of WT and hepcidin KO mice revealed that acid secretion in hepcidin-deficient mice is markedly reduced and is associated with gastric bacterial overgrowth, expression changes in multiple factors involved in acid secretion (Atp4a, Cck2r,Gas, Sst and Sst2r) and with reduced circulating gastrin levels. In WT mice, pantoprazole activated and histamine downregulated hepcidin expression levels. CONCLUSIONS: Hepcidin is a product of parietal cells regulating gastric acid production and may contribute to development of gastric ulcers under stress conditions.

B and T lymphocyte attenuator restricts the protective immune response against experimental malaria.

The immune response against the blood stage of malaria has to be tightly regulated to allow for vigorous antiplasmodial activity while restraining potentially lethal immunopathologic damage to the host like cerebral malaria. Coinhibitory cell surface receptors are important modulators of immune activation. B and T lymphocyte attenuator (BTLA) (CD272) is a coinhibitory receptor expressed by most leukocytes, with the highest expression levels on T and B cells, and is involved in the maintenance of peripheral tolerance by dampening the activation of lymphocytes. The function of BTLA is described in several models of inflammatory disorders and autoimmunity, but its function in infectious diseases is less well characterized. Also, little is known about the influence of BTLA on non-T cells. In this study, we analyzed the function of BTLA during blood-stage malaria infection with the nonlethal Plasmodium yoelii strain 17NL. We show that BTLA knockout mice exhibit strongly reduced parasitemia and clear the infection earlier compared with wild-type mice. This increased resistance was seen before the onset of adaptive immune mechanisms and even in the absence of T and B cells but was more pronounced at later time points when activation of T and B cells was observed. We demonstrate that BTLA regulates production of proinflammatory cytokines in a T cell-intrinsic way and B cell intrinsically regulates the production of P. yoelii 17NL-specific Abs. These results indicate that the coinhibitory receptor BTLA plays a critical role during experimental malaria and attenuates the innate as well as the subsequent adaptive immune response.

Prevalence of Helicobacter pylori in the adolescent oral cavity: dependence on orthodontic therapy, oral flora and hygiene.

BACKGROUND: Helicobacter pylori (HP) infection usually occurs in childhood. While there are various studies on the prevalence of HP in dental plaque, ours is the first to analyze its prevalence during orthodontic therapy and its interaction with competitive bacteria in adolescents. SUBJECTS AND METHODS: The prevalence of HP was examined before and during the first 12 weeks of orthodontic therapy with fixed appliances in 11 patients with a mean age of 12.7 years. A total of 93 plaque samples were analyzed using PCR. The data acquired at every consultation were the following: PCR analysis of dental plaque and (13)C urea breath tests for HP, quantitative analyses of saliva for Lactobacilli and Streptococcus mutans, the interproximal plaque index (API), and sulcus bleeding index (SBI). RESULTS: The prevalence of HP in plaque was 82% before orthodontic therapy, dropping to 54% during therapy (t test, p≤0.05). In contrast to HP's prevalence, the Lactobacilli count rose (p≤0.05). The number of Streptococcus mutans bacteria in saliva decreased during orthodontic therapy (p≤0.05). CONCLUSION: The prevalence of HP in dental plaque amounted to 82%. Orthodontic treatment did not reduce its prevalence. The prevalence of Lactobacilli was inversely proportional to that of HP.

Protein kinase D2 is a novel regulator of glioblastoma growth and tumor formation.

Glioblastoma multiforme, a highly aggressive tumor of the central nervous system, has a dismal prognosis that is due in part to its resistance to radio- and chemotherapy. The protein kinase C (PKC) family of serine threonine kinases has been implicated in the formation and proliferation of glioblastoma multiforme. Members of the protein kinase D (PKD) family, which consists of PKD1, -2 and, -3, are prominent downstream targets of PKCs and could play a major role in glioblastoma growth. PKD2 was highly expressed in both low-grade and high-grade human gliomas. The number of PKD2-positive tumor cells increased with glioma grading (P < .001). PKD2 was also expressed in CD133-positive glioblastoma stem cells and various glioblastoma cell lines in which the kinase was found to be constitutively active. Inhibition of PKDs by pharmacological inhibitors resulted in substantial inhibition of glioblastoma proliferation. Furthermore, specific depletion of PKD2 by siRNA resulted in a marked inhibition of anchorage-dependent and -independent proliferation and an accumulation of glioblastoma cells in G0/G1, accompanied by a down-regulation of cyclin D1 expression. In addition, PKD2-depleted glioblastoma cells exhibited substantially reduced tumor formation in vivo on chicken chorioallantoic membranes. These findings identify PKD2 as a novel mediator of glioblastoma cell growth in vitro and in vivo and thereby as a potential therapeutic target for this devastating disease.

Intravenous ibandronate or sodium-fluoride--a 3.5 years study on bone density and fractures in Crohn's disease patients with osteoporosis.

BACKGROUND AND AIM: Osteoporosis commonly afflicts Crohn's disease (CD) patients. Management remains unclear, with limited results for intravenous (i.v.) bisphosphonates and a follow-up longer than one year. Intravenous bisphosphonates bypass gastrointestinal-tract irritation offering an interesting alternative suitable for CD patients. We tested the long-term efficacy and safety of colecalciferol and calcium with sodium-fluoride or i.v. ibandronate for osteoporosis in CD. METHODS: 66 CD patients with lumbar osteoporosis (T-score<-2.5) were randomized to receive colecalciferol (1000 IU), calcium-citrate (800 mg) and intermittent sustained-release sodium-fluoride (50 mg) [groupA, n=33] or i.v. ibandronate (1 mg/3-monthly) [groupB, n=33]. Dual-energy X-ray absorptiometry of the lumbar-spine and right femur and X-rays of the spine were performed at baseline and after 1.0, 2.25 and 3.5 years. Fracture-assessment included visual reading and quantitative morphometry of X-rays. RESULTS: 55 (83.3%) patients completed at least the 1st year available for intention-to-treat (ITT) analysis, 42 (63.6%) completed the 2nd and 35 (53.0%) the 3rd year available for per-protocol analysis. Lumbar T-score increased by +0.23±0.43 (95%CI: 0.057-0.407, p<0.05), +0.71±1.05 (95%CI: 0.193-1.232, p<0.001) and +0.73±0.82 (95%CI: 0.340-1.336, p<0.001) (group A), and +0.28±0.41 (95%CI: 0.132-0.459, p<0.05), +0.43±0.55 (95%CI: 0.184-0.671, p<0.01) and +0.51±0.74 (95%CI: 0.145-0.882, p<0.001) (group B) during 1.0, 2.25 and 3.5 years follow-up time. In 2.71 years of follow-up, with the ITT analysis, the lumbar T-score increased by +0.66±0.97 (group A, p<0.001) and +0.46±0.67 (group B, p<0.001). One vertebral fracture with sodium-fluoride was not enough to detect differences between groups and the study was not powered for this. Study medication was well-tolerated and safe. CONCLUSIONS: Sodium-fluoride and i.v. ibandronate improved osteoporosis. Keeping in mind bisphosphonates as a standard of osteoporosis care that reduce fracture-rate, data we do not have for sodium-fluoride, CD patients with osteoporosis can be treated safely with i.v. ibandronate.

Inflammation, regeneration, and transformation in the pancreas: results of the Collaborative Research Center 518 (SFB 518) at the University of Ulm.

The primary diseases of the pancreas include diabetes mellitus, acute and chronic pancreatitis, as well as pancreatic carcinoma. This review presents findings and emerging questions on the diseases of the pancreas obtained by the consortium of the Collaborative Research Center 518 (SFB 518), "Inflammation, Regeneration, and Transformation in the Pancreas" at the University of Ulm. During the last 12 years, the SFB 518 contributed considerably to the understanding of the cellular and molecular basis of pancreatic diseases and established the basis for the development of new strategies for prevention and causal therapy for diabetes, pancreatitis, and pancreatic cancer.

Regeneration of the exocrine pancreas is delayed in telomere-dysfunctional mice.

INTRODUCTION: Telomere shortening is a cell-intrinsic mechanism that limits cell proliferation by induction of DNA damage responses resulting either in apoptosis or cellular senescence. Shortening of telomeres has been shown to occur during human aging and in chronic diseases that accelerate cell turnover, such as chronic hepatitis. Telomere shortening can limit organ homeostasis and regeneration in response to injury. Whether the same holds true for pancreas regeneration in response to injury is not known. METHODS: In the present study, pancreatic regeneration after acute cerulein-induced pancreatitis was studied in late generation telomerase knockout mice with short telomeres compared to telomerase wild-type mice with long telomeres. RESULTS: Late generation telomerase knockout mice exhibited impaired exocrine pancreatic regeneration after acute pancreatitis as seen by persistence of metaplastic acinar cells and markedly reduced proliferation. The expression levels of p53 and p21 were not significantly increased in regenerating pancreas of late generation telomerase knockout mice compared to wild-type mice. CONCLUSION: Our results indicate that pancreatic regeneration is limited in the context of telomere dysfunction without evidence for p53 checkpoint activation.

Protein kinase D2 is an essential regulator of murine myoblast differentiation.

Muscle differentiation is a highly conserved process that occurs through the activation of quiescent satellite cells whose progeny proliferate, differentiate, and fuse to generate new myofibers. A defined pattern of myogenic transcription factors is orchestrated during this process and is regulated via distinct signaling cascades involving various intracellular signaling pathways, including members of the protein kinase C (PKC) family. The protein kinase D (PKD) isoenzymes PKD1, -2, and -3, are prominent downstream targets of PKCs and phospholipase D in various biological systems including mouse and could hence play a role in muscle differentiation. In the present study, we used a mouse myoblast cell line (C2C12) as an in vitro model to investigate the role of PKDs, in particular PKD2, in muscle stem cell differentiation. We show that C2C12 cells express all PKD isoforms with PKD2 being highly expressed. Furthermore, we demonstrate that PKD2 is specifically phosphorylated/activated during the initiation of mouse myoblast differentiation. Selective inhibition of PKCs or PKDs by pharmacological inhibitors blocked myotube formation. Depletion of PKD2 by shRNAs resulted in a marked inhibition of myoblast cell fusion. PKD2-depleted cells exhibit impaired regulation of muscle development-associated genes while the proliferative capacity remains unaltered. Vice versa forced expression of PKD2 increases myoblast differentiation. These findings were confirmed in primary mouse satellite cells where myotube fusion was also decreased upon inhibition of PKDs. Active PKD2 induced transcriptional activation of myocyte enhancer factor 2D and repression of Pax3 transcriptional activity. In conclusion, we identify PKDs, in particular PKD2, as a major mediator of muscle cell differentiation in vitro and thereby as a potential novel target for the modulation of muscle regeneration.