Targeted delivery of a vaccine protein to Langerhans cells in the human skin via the C-type lectin receptor Langerin

Human skin is a preferred vaccination site as it harbors multiple dendritic cell (DC) subsets, which display distinct C-type lectin receptors (CLR) that recognize pathogens. Antigens can be delivered to CLR by antibodies or ligands to boost antigen-specific immune responses. This concept has been established in mouse models but detailed insights into the functional consequences of antigen delivery to human skin DC in situ are sparse. In this study, we cloned and produced an anti-human Langerin antibody conjugated to the EBV nuclear antigen 1 (EBNA1). We confirmed specific binding of anti-Langerin-EBNA1 to Langerhans cells (LC). This novel LC-based vaccine was then compared to an existing anti-DEC-205-EBNA1 fusion protein by loading LC in epidermal cell suspensions before coculturing them with autologous T cells. After restimulation with EBNA1-peptides, we detected elevated levels of IFN-γ- and TNF-α-positive CD4+ T cells with both vaccines. When we injected the fusion proteins intradermally into human skin explants, emigrated skin DC targeted via DEC-205-induced cytokine production by T cells, whereas the Langerin-based vaccine failed to do so. In summary, we demonstrate that antibody-targeting approaches via the skin are promising vaccination strategies, however, further optimizations of vaccines are required to induce potent immune responses

Aberrant Lck Signal via CD28 Costimulation Augments Antigen-Specific Functionality and Tumor Control by Redirected T Cells with PD-1 Blockade in Humanized Mice

Combination therapy of adoptively transferred redirected T cells and checkpoint inhibitors aims for higher response rates in tumors poorly responsive to immunotherapy like malignant pleural mesothelioma (MPM). Only most recently the issue of an optimally active chimeric antigen receptor (CAR) and the combination with checkpoint inhibitors is starting to be addressed. Fibroblast activation protein (FAP)-specific CARs with different costimulatory domains, including CD28, Δ-CD28 (lacking lck binding moiety), or 4-1BB were established. CAR-T cells were characterized and antitumor efficacy was tested in a humanized mouse model in combination with PD-1 blockade. Finally, the Δ-CD28 CAR was tested clinically in a patient with MPM. All the three CARs demonstrated FAP-specific functionality Gene expression data indicated a distinct activity profile for the Δ-CD28 CAR, including higher expression of genes involved in cell division, glycolysis, fatty acid oxidation, and oxidative phosphorylation. only T cells expressing the Δ-CD28 CAR in combination with PD-1 blockade controlled tumor growth. When injected into the pleural effusion of a patient with MPM, the Δ-CD28 CAR could be detected for up to 21 days and showed functionality. Overall, anti-FAP-Δ-CD28/CD3ζ CAR T cells revealed superior functionality, better tumor control in combination with PD-1 blockade in humanized mice, and persistence up to 21 days in a patient with MPM. Therefore, further clinical investigation of this optimized CAR is warranted

Outcome quality of Herbst-Multibracket appliance treatment in Class II:1 patients

Das Ziel der vorliegenden Studie war es die Versorgungsqualität aller Klasse II:1 Patienten, die im Zeitraum von 1986 bis 2014 in der Poliklinik für Kieferorthopädie des Zentrums für Zahn-, Mund- und Kieferheilkunde der Justus-Liebig-Universität Gießen mit der Herbst- und unmittelbar danach mit einer Multibracket-Apparatur behandelt wurden, zu beurteilen. Die PAR-Punktwert-Reduzierung (RICHMOND et al. 1992 a, 1992b) und die Ergebniskategorien nach AHLGREN (1988) dienten als Hauptzielparameter. Zusätzlich wurden die okklusalen Variablen, das Auftreten von Rezessionen, das Bestehen von Habits und Funktionsstörungen zu Behandlungsbeginn sowie der Einfluss der skelettalen Reife und der Ausprägungsgrad der Distalokklusion auf die Versorgungsqualität als Nebenzielparameter definiert. Es wurde das Ergebnis der aktiven Behandlung als auch das der entsprechenden Kurzzeitstabilität berücksichtigt. Folgende Einschlusskriterien wurden formuliert: • Angle-Klasse II:1 bei Behandlungsbeginn • Herbst-Multibracket-Behandlung • Aktive Behandlung bis maximal Ende 2014 • Optional: größer gleich 24 monatige Nachbeobachtungsphase Das Patientengut umfasste 508 Patienten zu Behandlungsbeginn (T1). Nach erfolgter Herbst-Multibracket-Behandlung (T2: 24,2 ± 7,8 Monate) standen jedoch lediglich Modelle von 490 Patienten zur Auswertung bereit. Diese Zahl reduzierte sich erneut im Hinblick auf die Auswertung der Kurzzeitstabilität, da nur 232 Patienten eine mindestens 24 monatige Retentionsphase (T3: 32,6 ± 15,8 Monate) durchlaufen hatten. Hinsichtlich der Versorgungsqualität wurden folgende Ergebnisse festgestellt: • Der anfängliche PAR-Wert konnte im Mittel von 32,4 ± 8,8 Punkten auf 8,0 ± 4,5 Punkte reduziert werden und blieb auch zu T3 weitestgehend stabil (8,8 ± 5,1 Punkte). • Die subjektive Beurteilung der Versorgungsqualität zu T3 mit der Methode nach AHLGREN (1988) stufte 16,8% als ausgezeichnetes, 34,9% als gutes, 44,0% als akzeptables, 2,2% als inakzeptables und 2,2% als nicht beurteilbares Behandlungsergebnis ein. • Der anfängliche Overjet konnte im Mittel von 7,1 ± 2,4 mm (rechts) bzw. 7,0 ± 2,3 mm (links) auf 2,0 ± 0,9 mm (beidseitig) reduziert werden und stieg auf 2,6 ± 0,9 mm (rechts) bzw. 2,7 ± 0,9 mm (links) an (T3). • Der Overbite konnte von durchschnittlich 4,0 ± 2,0 mm (rechts) bzw. 4,1 ± 1,9 mm (links) auf 1,5 ± 0,9 mm (beidseitig) reduziert werden und stieg zu T3 auf 2,0 ± 1,2 mm (beidseitig) an. • Zu T1 lag sowohl im Molaren- als auch im Eckzahnbereich durchschnittlich eine Distalokklusion von einer ¾ Prämolarenbreite vor. Durch die Herbst-Multibracket-Behandlung konnte mehrheitlich eine neutrale oder überkorrigierte Molarenverzahnung erzielt werden, die auch zu T3 stabil blieb. Im Eckzahnbereich stellte sich sowohl zu T2 als auch zu T3 eine leichte Distalokklusion von ¼ Prämolarenbreite ein. • Es konnte kein Zusammenhang zwischen der skelettalen Reife und der PAR-Wert-Reduktion (T2: r=0,057; T3: r=0,031) und kein (T2: r=0,154) bzw. lediglich ein leichter Zusammenhang zwischen dem Ausprägungsgrad der Malokklusion und der PAR-Wert-Reduktion (T3: r=0,23) festgestellt werden. • Zu T1 wiesen 13,6% der Patienten Rezessionen auf. Dieser Anteil stieg auf 43,1% zu T3. Zu T3 zeigten insgesamt 5,2% der untersuchten Zähne Rezessionen. Darunter waren am häufigsten die unteren Inzisivi betroffen (2,1%). • Zu T1 wiesen 79,3% der untersuchten Patienten mindestens ein Habit bzw. eine Dysfunktion auf. Hierbei traten die Mundatmung (17,3%), das atypische Schluckmuster (14,9%) und das Bestehen eines Lutschhabits (12,4%) unter den Patienten mit Habit respektive Dysfunktion am häufigsten auf. Zusammenfassend lässt sich sagen, dass die kombinierte Herbst-Multibracket-Behandlung eine effektive Behandlungsmethode für die Angle-Klasse II:1 Dysgnathie darstellt, die zudem unabhängig von der skelettalen Reife und weitestgehend unabhängig vom Ausprägungsgrad der Distalokklusion ist.The aim of the present study was to evaluate the outcome quality of all Class II:1 patients, who received Herbst and subsequent Multibracket appliance treatment at the Department of Orthodontics, University of Giessen, between 1986 and 2014. The PAR score reduction (RICHMOND et al. 1992a, 1992b) as well as the outcome rating according to AHLGREN (1988) were the main study parameters. In addition, secondary study parameters (occlusal variables, prevalence of recessions, habits and dysfunctions which existed before the start of treatment) and the impact of skeletal maturity and severity of Class II relationship on the treatment outcome were analyzed. Both the results of active treatment and the corresponding short-term stability were considered. The following inclusion criteria were defined: • Class II:1 at the start of treatment • Herbst-Multibracket treatment • Active treatment finished before the end of 2014 • Optional: greater or equal 24 months follow-up observation period The sample comprised 508 at the start of treatment (T1). However, after Herbst-Multibracket treatment (T2: 24.2 ± 7.8 months) study casts of only 490 patients were available for evaluation. Intents of short-term stability study casts of 232 patients who had fulfilled an observation period of at least 24 months (T3: 32.6 ± 15.8 months) were available. In terms of outcome quality the following results were determined: • During treatment the initial PAR score was reduced from 32.0 ± 8.8 to 8.0 ± 4.5 points and remained mostly stable during the follow-up period (8.8 ± 5.1 points). • The outcome ratings according to AHLGREN (1988) at T3 classified 16.8% as excellent, 34.9% as good, 44.0% as acceptable, 2.2% as not acceptable and 2.2% as not assessable treatment outcome. • The initial overjet was reduced from 7.1 ± 2.4 mm (right) respectively 7.0 ± 2.3 mm (left) to 2.0 ± 0.9 mm (on both sides). During the follow-up period the overjet increased to 2.6 ± 0.9 mm (right) respectively 2.7 ± 0.9 mm (left). • The overbite was reduced from 4.0 ± 2.0 mm (right) respectively 4.1 ± 1.9 mm (left) to 1.5 ± 0.9 mm (on both sides) during treatment and increased to 2.0 ± 1.2 mm (on both sides) during the post-treatment observation period. • Before treatment the average Class II relationship was ¾ cusp widths. Due to Herbst-Multibracket treatment a Class I or overcorrected Class I relationship was achieved in most cases and remained more or less stable during the follow-up period. For the canines a slight Class II relationship of ¼ cusp widths was present at T2 as well as T3. • No correlation was found between skeletal maturity and PAR score reduction (T2: r=0.057; T3: r=0.031) as well as between severity of Class II relationship after treatment and PAR score reduction (T2: r=0.154). A low association was found between the severity of Class II relationship after the follow-up period and PAR score reduction (T3: r=0.23). • The prevalence of gingival recessions was 13.6% (of all patients) before treatment. This amount increased to 43.1% after the follow-up period. Overall 5.2% of all examined teeth showed recessions at T3 with the lower incisors being most frequently (2.1%) affected. • At T1 79.3% of all examined patients had at least one habit or dysfunction: mouth breathing (17.3%), tongue thrust swallowing (14.9%) and the existence of a sucking habit (12.4%) were the most common ones. In summary Herbst-Multibracket treatment can be considered as a successful treatment option for Class II:1 patients irrespective of pre-treatment severity of the Class II relationship or pre-treatment skeletal maturity

Vaccination against the Epstein–Barr virus

Epstein–Barr virus (EBV) was the first human tumor virus being discovered and remains to date the only human pathogen that can transform cells in vitro. 55 years of EBV research have now brought us to the brink of an EBV vaccine. For this purpose, recombinant viral vectors and their heterologous prime-boost vaccinations, EBV-derived virus-like particles and viral envelope glycoprotein formulations are explored and are discussed in this review. Even so, cell-mediated immune control by cytotoxic lymphocytes protects healthy virus carriers from EBV-associated malignancies, antibodies might be able to prevent symptomatic primary infection, the most likely EBV-associated pathology against which EBV vaccines will be initially tested. Thus, the variety of EBV vaccines reflects the sophisticated life cycle of this human tumor virus and only vaccination in humans will finally be able to reveal the efficacy of these candidates. Nevertheless, the recently renewed efforts to develop an EBV vaccine and the long history of safe adoptive T cell transfer to treat EBV-associated malignancies suggest that this oncogenic γ-herpesvirus can be targeted by immunotherapies. Such vaccination should ideally implement the very same immune control that protects healthy EBV carriers

MicroRNAs of Epstein-Barr Virus Attenuate T-Cell-Mediated Immune Control In Vivo

The human persistent and oncogenic Epstein-Barr virus (EBV) was one of the first viruses that were described to express viral microRNAs (miRNAs). These have been proposed to modulate many host and viral functions, but their predominant role in vivo has remained unclear. We compared recombinant EBVs expressing or lacking miRNAs during in vivo infection of mice with reconstituted human immune system components and found that miRNA-deficient EBV replicates to lower viral titers with decreased frequencies of proliferating EBV-infected B cells. In response, activated cytotoxic EBV-specific T cells expand to lower frequencies than during infection with miRNA-expressing EBV. However, when we depleted CD8$^{+}$ T cells the miRNA-deficient virus reached similar viral loads as wild-type EBV, increasing by more than 200-fold in the spleens of infected animals. Furthermore, CD8$^{+}$ T cell depletion resulted in lymphoma formation in the majority of animals after miRNA-deficient EBV infection, while no tumors emerged when CD8$^{+}$ T cells were present. Thus, miRNAs mainly serve the purpose of immune evasion from T cells in vivo and could become a therapeutic target to render EBV-associated malignancies more immunogenic.IMPORTANCE Epstein-Barr virus (EBV) infects the majority of the human population and usually persists asymptomatically within its host. Nevertheless, EBV is the causative agent for infectious mononucleosis (IM) and for lymphoproliferative disorders, including Burkitt and Hodgkin lymphomas. The immune system of the infected host is thought to prevent tumor formation in healthy virus carriers. EBV was one of the first viruses described to express miRNAs, and many host and viral targets were identified for these in vitro However, their role during EBV infection in vivo remained unclear. This work is the first to describe that EBV miRNAs mainly increase viremia and virus-associated lymphomas through dampening antigen recognition by adaptive immune responses in mice with reconstituted immune responses. Currently, there is no prophylactic or therapeutic treatment to restrict IM or EBV-associated malignancies; thus, targeting EBV miRNAs could promote immune responses and limit EBV-associated pathologies

Attenuated immune control of Epstein-Barr virus in humanized mice is associated with the multiple sclerosis risk factor HLA-DR15

Immune responses to Epstein-Barr virus (EBV) infection synergize with the main genetic risk factor HLA-DRB1*15:01 (HLA-DR15) to increase the likelihood to develop the autoimmune disease multiple sclerosis (MS) at least sevenfold. In order to gain insights into this synergy, we investigated HLA-DR15 positive human immune compartments after reconstitution in immune-compromised mice (humanized mice) with and without EBV infection. We detected elevated activation of both CD4$^{+}$ and CD8$^{+}$ T cells in HLA-DR15 donor-reconstituted humanized mice at steady state, even when compared to immune compartments carrying HLA-DRB1*04:01 (HLA-DR4), which is associated with other autoimmune diseases. Increased CD8$^{+}$ T cell expansion and activation was also observed in HLA-DR15 donor-reconstituted humanized mice after EBV infection. Despite this higher immune activation, EBV viral loads were less well controlled in the context of HLA-DR15. Indeed, HLA-DR15-restricted CD4$^{+}$ T cell clones recognized EBV-transformed B cell lines less efficiently and demonstrated cross-reactivity toward allogeneic target cells and one MS autoantigen. These findings suggest that EBV as one of the main environmental risk factors and HLA-DR15 as the main genetic risk factor for MS synergize by priming hyperreactive T-cell compartments, which then control the viral infection less efficiently and contain cross-reactive CD4$^{+}$ T cell clones

Chikungunya virus envelope protein E2 provides a vector for targeted antigen delivery to human dermal CD14 + dendritic cells

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Changes of variables during the study period.

<p>Columns show the median. Parameters with significant changes between visit 1 and visit 4 are listed. P values indicate the changes of visits 2–4 compared to visit 1. *indicates highly significant changes of p<0.005.</p