Naturally circulating pertactin-deficient Bordetella pertussis strains induce distinct gene expression and inflammatory signatures in human dendritic cells

Respiratory infections caused by Bordetella pertussis are reemerging despite high pertussis vaccination coverage. Since the introduction of the acellular pertussis vaccine in the late twentieth century, circulating B. pertussis strains increasingly lack expression of the vaccine component pertactin (Prn). In some countries, up to 90% of the circulating B. pertussis strains are deficient in Prn. To better understand the resurgence of pertussis, we investigated the response of human monocyte-derived dendritic cells (moDCs) to naturally circulating Prn-expressing (Prn-Pos) and Prn-deficient (Prn-Neg) B. pertussis strains from 2016 in the Netherlands. Transcriptome analysis of moDC showed enriched IFNα response-associated gene expression after exposure to Prn-Pos B. pertussis strains, whereas the Prn-Neg strains induced enriched expression of interleukin- and TNF-signaling genes, as well as other genes involved in immune activation. Multiplex immune assays confirmed enhanced proinflammatory cytokine secretion by Prn-Neg stimulated moDC. Comparison of the proteomes from the Prn-Pos and Prn-Neg strains revealed, next to the difference in Prn, differential expression of a number of other proteins including several proteins involved in metabolic processes. Our findings indicate that Prn-deficient B. pertussis strains induce a distinct and stronger immune activation of moDCs than the Prn-Pos strains. These findings highlight the role of pathogen adaptation in the resurgence of pertussis as well as the effects that vaccine pressure can have on a bacterial population.

Specific memory B cell response in humans upon infection with highly pathogenic H7N7 avian influenza virus

H7 avian influenza viruses represent a major public health concern, and worldwide outbreaks raise the risk of a potential pandemic. Understanding the memory B cell response to avian (H7) influenza virus infection in humans could provide insights in the potential key to human infection risks. We investigated an epizootic of the highly pathogenic A(H7N7) in the Netherlands, which in 2003 led to infection of 89 persons and one fatal case. Subtype-specificity of antibodies were determined for confirmed H7N7 infected individuals (cases) (n = 19), contacts of these cases (n = 21) and a comparison group controls (n = 16), by microarray, using recombinant hemagglutinin (HA)1 proteins. The frequency and specificity of memory B cells was determined by detecting subtype-specific antibodies in the culture supernatants from in vitro stimulated oligoclonal B cell cultures, from peripheral blood of cases and controls. All cases (100%) had high antibody titers specific for A(H7N7)2003 (GMT > 100), whereas H7-HA1 antigen binding was detected in 29% of contacts and 31% of controls, suggesting that some of the H7 reactivity stems from cross reactive antibodies. To unravel homotypic and heterotypic responses, the frequency and specificity of memory B cells were determined in 2 cases. Ten of 123 HA1 reactive clones isolated from the cases bound to only H7- HA1, whereas 5 bound both H7 and other HA1 antigens. We recovered at least four different epitopal reactivities, though none of the H7 reactive antibodies were able to neutralize H7 infections in vitro. Our study serologically confirms the infection with H7 avian influenza viruses, and shows that H7 infection triggers a mixture of strain -specific and cross-reactive antibodies.

Whole-Inactivated Influenza Virus Is a Potent Adjuvant for Influenza Peptides Containing CD8+ T Cell Epitopes

Influenza peptide antigens coding for conserved T cell epitopes have the capacity to induce cross-protective influenza-specific immunity. Short peptide antigens used as a vaccine, however, often show poor immunogenicity. In this study, we demonstrate that whole-inactivated influenza virus (WIV) acts as an adjuvant for influenza peptide antigens, as shown by the induction of peptide-specific CD8⁺ T cells in HLA-A2.1 transgenic mice upon vaccination with the influenza-M1-derived GILGFVFTL peptide (GIL), formulated with WIV. By screening various concentrations of GIL and WIV, we found that both components contributed to the GIL-specific T cell response. Whereas co-localization of the peptide antigen and WIV adjuvant was found to be important, neither physical association between peptide and WIV nor fusogenic activity of WIV were relevant for the adjuvant effect of WIV. We furthermore show that WIV may adjuvate T cell responses to a variety of peptides, using pools of either conserved wild-type influenza peptides or chemically altered peptide ligands. This study shows the potential of WIV as an adjuvant for influenza peptides. The simple formulation process and the solid safety record of WIV make this an attractive adjuvant for T cell peptides, and may also be used for non-influenza antigens.

Die perivaskuläre Sympathektomie beim Pferd – neue anatomisch-histologische Erkenntnisse

Gegenstand: In der vorliegenden Arbeit wurden Abschnitte der A., V. und des N. digitalis palmaris medialis der linken Schultergliedmaße eines gesunden Pferdes im Vergleich zu einem vier Wochen nach der perivaskulären Sympathektomie (PVS) aus anderen Gründen euthanasierten Pferdes untersucht und verglichen. Die PVS wird in der Pferdeklinik Barkhof als Therapieform des Podotrochlose-Sesamoidose-Syndroms seit 1987 erfolgreich eingesetzt. An den untersuchten operierten Gefäßen sollte das Ausmaß (die Vollständigkeit) der Sympathektomie ermittelt werden. Material und Methoden: Das Untersuchungsmaterial wurde immunhistochemisch auf das Vorhandensein sensibler (CGRP-positiver) und autonomer sympathischer (Tyrosin-Hydroxylase-positiver) Nervenfasern untersucht. Ergebnisse: Die Gefäße der gesunden Pferdegliedmaße waren sowohl autonom als auch sensibel innerviert, wobei die sympathischen Nervenfasern bis in das äußere Mediadrittel reichten, während die CGRP-positiven Fasern nur bis in die Adventitia zogen. Nach der perivaskulären Operation nach Jacobi ließen sich immunhistochemisch weder Tyrosin- Hydroxylase- noch CGRP-positive Nervenfasern in den Gefäßwänden nachweisen. Damit wurde das Ziel der Operation, die vasokonstriktiven Bahnen auszuschalten, erreicht. Schlussfolgerung und klinische Relevanz: Die gleichzeitige Entfernung der sensiblen afferenten Gefäßinnervation trägt auch einen Teil zur Unterbrechung des Circulus vitiosus, bestehend aus Schmerz – Gefäßverengung – Ischämie – Funktionsstörung – Schmerz, bei. Da die Schmerzreize nicht mehr ins ZNS weitergeleitet werden können, wird somit die schmerzbedingte reflektorische Engstellung der arteriellen Endstrombahnen als Schmerzursache unterbrochen. Ein multifaktoriell ausgelöstes pathogenes Geschehen wie die Minderdurchblutung der Sesambeine mit nachfolgender Degeneration des Gewebes kann durch eine chirurgische Maßnahme, die mehr als eine Gewebskomponente betrifft, mit guten klinischen Erfolgen gestoppt und in vielen Fällen dauerhaft gebessert werden.

Rapid reconstitution of CD4 T cells and NK cells protects against CMV-reactivation after allogeneic stem cell transplantation

BACKGROUND

Epstein-Barr virus and Cytomegalovirus reactivations frequently occur after allogeneic stem cell transplantation (SCT).

METHODS

Here we investigated the role of immune cell reconstitution in the onset and subsequent severity of EBV- and CMV-reactivation. To this end, 116 patients were prospectively sampled for absolute T cell (CD4 and CD8), B-cell (CD19) and NK-cell (CD16 and CD56) numbers weekly post-SCT during the first 3 months and thereafter monthly until 6 months post-SCT. Viral load was monitored in parallel.

RESULTS

In contrast to the general belief, we found that early T-cell reconstitution does not play a role in the onset of viral reactivation. CMV reactivation in the first 7 weeks after SCT however resulted in higher absolute CD8(+) T-cell numbers 6 months post-SCT in patients with high-level reactivation, many of which were CMV-specific. Interestingly, rapid reconstitution of CD4(+) T-cells, as well as NK cells and the presence of donor KIR3DL1, are associated with the absence of CMV-reactivation after SCT, suggestive of a protective role of these cells. In contrast, EBV-reactivations were not affected in any way by the level of immune reconstitution after SCT.

CONCLUSION

In conclusion, these data suggest that CD4(+) T-cells and NK cells, rather than CD8(+) T-cells, are associated with protection against CMV-reactivation.

Discriminative expression of whole blood genes in HIV patients with latent and active TB in Ethiopia

BACKGROUND

Transcriptomic host biomarkers could assist in developing effective diagnostics, vaccines and therapeutics for tuberculosis (TB). However, different biomarkers may be discriminatory in different populations depending on the host and bacillary genetics and HIV infection, and need to be addressed.

METHODS

The expression levels of 45 genes that are known to be involved in or affected by TB pathogenesis were analyzed using dual color Reverse Transcriptase Multiplex Ligation-dependent Probe Amplification (dcRT-MLPA) assay in whole blood of 106 HIV positive individuals including active TB patients (TB(+)HIV(+), n = 29), and non TB patients that are tuberculin skin test positive (TST+) (TST(+)HIV(+), n = 26), or TST negative (TST(-)HIV(+), n = 51).

RESULTS

Between the two clinical groups (TB(+)HIV(+) vs. TST(-)HIV(+)) 8 genes were differently expressed (CCL19, CD14, CD8A, FPR1, IL7R, CCL22, TNFRSF1A, and FCGR1A); between TB(+)HIV(+) vs. TST(+)HIV(+), 6 genes (CD14, IL7R, TIMP2, CCL22, TNFRSF1A, and FCGR1A) were differently expressed. Since no difference in gene expression was revealed between TST(+)HIV(+) vs. TST(-)HIV(+), we clustered both the TST(+)HIV(+) and TST(-)HIV(+) individuals as one group (TST(+/-)HIV(+)) and compared gene expression with TB(+)HIV(+) patients. Thus, the results revealed that the levels of five genes (CD8A, TIMP2, CCL22, FCGR1A and TNFRSF1A) were the most accurate single gene markers for differentiation between TB(+)HIV(+) and TST(+/-)HIV(+), with AUCs of 0.71, 0.71, 0.79, 0.83 and 0.73, respectively. However, the combination of two genes (CCL22 + FCGR1A) and FCGR1A alone were the most accurate marker for differentiation between the two groups (TB(+)HIV(+) and TST(+/-)HIV(+)) with AUC of 0.85 and 0.83, respectively.

CONCLUSIONS

We showed that five genes (CD8A, TIMP2, CCL22, FCGR1A and TNFRSF1A), specifically FCGR1A and CCL22 have the potential to discriminate active TB from non-active TB in HIV patients in Ethiopia and could be used to improve diagnostic tools for active TB in HIV patients, and to understand the pathogenesis of TB/HIV coinfection.

Increased proportion of perforin-expressing CD8+T-cells indicates control of herpesvirus reactivation in children after stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) is frequently complicated by viral reactivations. Early diagnosis of viral reactivations and preemptive therapy relies on frequent viralload monitoring. An easy marker of effective cytotoxicity in lymphopenia is lacking and therefore we studied perforin-expression in CD8+T-cells in children following HSCT. Prospectively, we weekly monitored viral loads and perforin-expression of CD8+T-cells in whole blood by FACS, until 4months after HSCT in children. 27 patients were included (median age 4,3, range 0.3-20,1years) of whom 19 developed viral reactivations. These patients showed higher percentages of perforin-expressing CD8+T-cells (17,2%, range 0-63%) than those without (6,8%; range 0-16%) (p=0.001). The increased percentage of perforin-expressing CD8+T-cells coincided with a decrease in viral load with a median interval between maximum viral load and maximum level of perforin-expression of 0,4weeks (range 0.1-7.1). We conclude that perforin-expression in CD8+T-cells may be a marker for effective antiviral T-cell reconstitution early after HSCT in children.

Isotope evidence for the intensive use of marine foods by Late Upper Palaeolithic humans

We report here on direct evidence for the intensive consumption of marine foods by anatomically modern humans at approximately 12,000 years ago. We undertook isotopic analysis of bone collagen from three humans, dating to the late Palaeolithic, from the site of Kendrick's Cave in North Wales, UK. The isotopic measurements of their bone collagen indicated that ca. 30% of their dietary protein was from marine sources, which we interpret as likely being high trophic level marine organisms such as marine mammals. This indicates that towards the end of the Pleistocene modern humans were pursuing a hunting strategy that incorporated both marine and terrestrial mammals. This is the first occurrence of the intensive use of marine resources, specifically marine mammals, that becomes even more pronounced in the subsequent Mesolithic period.

Perivaskuläre Sympathektomie, eine Therapiemöglichkeit beim Podotrochlose-/Sesamoidose-Syndrom

Es wird kurz zur Geschichte der periarteriellen Sympathektomie Stellung genommen. Aufbauend auf der Ischämie- und Belastungstheorie bei der Pathogenese der Podotrochlose und auf der Arteriosklerosetheorie bei der Sesamoidose wird zur Therapie mit Cumarinderivaten und Vasodilatanzien Stellung genommen. Anstelle einer konservativen Therapie wird die von Kulczycki 1958 (15) empfohlene periarterielle Sympathektomie, verbunden mit einer Fasziotomie (9) als chirurgische Behandlungsmethode mit schnellem Wirkungseintritt und lang anhaltender funktioneller Heilung empfohlen. Diese Methode wurde 1983 (7) als Alternative zur medikamentösen Therapie bei Podotrochlose und Sesamoidose eingeführt. Der angiographische Nachweis der Gefäßweitstellung und Durchblutungssteigerung wurde 1992 geführt (19). Als Nachweismethoden einer erfolgreichen perivaskulären Sympathektomie werden die Thermographie, das beschleunigte Hornwachstum und die vorläufigen Resultate einer klinischen Studie angeführt. Weitere Untersuchungen befassen sich mit 11 Patienten, die an Podotrochlose und Sesamoidose litten, mit perivaskulärer Sympathektomie und Fasziotomie behandelt und ein bis vier Jahre p. op. röntgenologisch nachuntersucht wurden. Die Fasziotomie/perivaskuläre Sympathektomie hat sich als erfolgreiche Behandlungsmethode bei Podotrochlose und Sesamoidose des Pferdes bewährt.

Pins, dowels, and other retentive devices in posterior teeth

Devices used to increase retention of restorations to severely damaged posterior teeth are described, with an emphasis on pins and dowels. Advantages and disadvantages of different techniques and measures to help prevent and correct problems are presented.

A comparison of the abrasiveness of six ceramic surfaces and gold

A type III gold alloy and six different ceramic surfaces were secured in an abrasion machine opposing extracted teeth to determine their relative abrasiveness and resistance to wear. The rankings of restorative materials from least abrasive to most abrasive were: gold alloy, polished; cast ceramic, polished; porcelain, polished; cast ceramic, polished and shaded; porcelain, polished and glazed; cast ceramic, cerammed skin shaded; and cast ceramic, cerammed skin unshaded. The ranking of materials from most wear-resistant to least wear-resistant was: gold alloy, cast ceramic cerammed, cast ceramic cerammed and shaded, porcelain polished, porcelain glazed, cast ceramic polished and shaded, and cast ceramic polished.

The ceramic reverse three-quarter crown for anterior teeth: laboratory procedures

The laboratory procedures for making a Hi-ceram porcelain anterior reserve three-quarter crown are described. A core of high-fusing aluminum oxide is used as a coping on which tooth contours are restored with a compatible porcelain. Standard dental laboratory equipment is used and the technique can be quickly learned by any experienced ceramics technician.

The ceramic reverse three-quarter crown for anterior teeth: preparation design

A new preparation design of the ceramic reverse three-quarter crown for anterior teeth offers a way to improve the appearance of anterior teeth with slight to moderate structural damage. Advantages and indications of the new design are discussed.

An intraoral lift technique for refining porcelain margins

A method has been described by which a paste of shoulder porcelain and light-curing resin is used to correct deficient porcelain margins. The resin-bonded porcelain is fired in an oven for final hardening.

Effect of abutment mobility, site, and angle of impact on retention of fixed partial dentures

Fixed partial dentures cemented to dies of adjustable mobility were subjected to repeated impacts at three different sites. Immobile abutments retained their prostheses longer than mobile abutments. Impacts that fell between the centers of rotation of the abutments were withstood longer than impacts that fell nearer the ends of the prostheses. This study failed to show a significant difference between the effect of impacts perpendicular to the occlusal plane and impacts angled 45 degrees toward the lingual plane. The results of this study suggest that (1) crowns that anchor rigid prostheses to mobile teeth require greater retentive ability than crowns on relatively immobile abutments and (2) occlusal impacts are best withstood when they fall on the areas of the fixed partial denture over and between the centers of rotation of the abutment teeth. If a fixed partial denture must withstand loading outside these areas, as is the case with cantilevered pontics and some tilted abutments, the retainer furthermost from the anticipated eccentric load must have exceptionally good retention.

Preparation modifications for damaged vital posterior teeth

The preservation of a severely damaged tooth with a cast restoration requires that the preparation be modified to make use of remaining tooth structure. Preexisting preparation features, such as boxes and isthmuses, and new ones, such as boxes, grooves, and pin holes, are employed to provide adequate retention and resistance. When destruction of coronal tooth structure exceeds one-half of the clinical crown, a pin-retained amalgam or composite resin core should be used to build up the tooth to receive a cast restoration.