No man is an island; no island is an island: does the immune network extend beyond the limits of skin?

Now that we are moving towards a post-antibiotic era, it may be necessary to reevaluate our concept of immunology. A long-standing handicap may be that, thus far, we have focused exclusively on the individual and his own immune machinery. A search for community interactions, also involving microflora, may provide clues for our survival under the extremely unhygienic conditions of the past as well as the present. Among the many adverse factors, could there also be hidden beneficial effects as well? If so, the development of such factors to therapeutic significance would be a worthwhile challenge. Diverse historical chronicles and a certain resistance shown by infants in shanty towns, after the maternal immune protection has faded and until their own immune system is fully developed, led us to postulate that adaptation is a prerequisite for any subject in order to benefit from unhygienic crowded conditions.     

Does the development of the perigeniculate nucleus support the notion of a hierarchical progression within the visual pathway?

The development of the visual pathway has been extensively studied. However, despite of the importance of the perigeniculate nucleus within this pathway, there is a lack of information concerning its development. The present study examined the dendritic development of perigeniculate nucleus cells using single cell injections in 400-500 microm thick fixed brain slices from kittens of different ages between postnatal day 0 and postnatal day 125. A total of 189 perigeniculate nucleus cells were reconstructed from serial sections for qualitative and quantitative analysis. Cells during the first month were characterized by an abundance of branch points and appendages. There was a significant (P>0.05), albeit variable, increase in the number of branch points and appendages up to about postnatal day 12 after which the numbers were rapidly reduced over the next two weeks. Similarly, appendage numbers significantly increased over the first two weeks until postnatal day 17 and then fell to near adult levels by postnatal day 34. The majority of branch points and appendages occur within 100-200 microm of the soma (10-30% of the dendritic diameter). The data indicate that perigeniculate nucleus dendritic maturation lags shortly behind that of the retina but may precede that of its dorsal thalamic target, the lateral geniculate nucleus. Thus, it may be that the earlier maturation of the perigeniculate nucleus and its inhibitory input is a necessary requirement for the proper development of retinogeniculate and corticothalamic topographic maps within the dorsal lateral geniculate nucleus and perigeniculate nucleus.     

Evaluation of the clinical performance of OncoPredict HPV® SCR assay within the VALGENT-2 framework

Human papillomavirus (HPV) assays used in cervical cancer screening should be clinically validated according to international criteria. OncoPredict HPV® Screening (SCR) is a partial genotyping multiplex real-time PCR assay targeting E6/E7 genes of 13 high-risk (hr) HPVs. OncoPredict HPV® SCR (index assay) identifies HPV-16 and HPV-18 separately, 11 other hrHPV in aggregate and includes quality controls for sample adequacy, DNA extraction efficiency and PCR inhibition. 1300 VALGENT-2 study samples (from women aged 20–60 attending the Scottish cervical cancer screening program) were tested with the index assay and the GP5+/6+ PCR enzyme immunoassay (standard comparator assay). Non-inferior accuracy detecting cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) of the index versus comparator was verified. Intra- and interlaboratory reproducibility of the index was evaluated by overall concordance and Cohen's kappa, using a sub-population (n = 526). Relative sensitivity and specificity for CIN2+ of the index versus comparator were 1.01 (95% confidence interval [CI]: 0.99–1.03) and 1.02 (95% CI: 1.0–1.04), respectively. Noninferiority p values were all ≤0.05, except for CIN3+ in patients ≥30 years. Excellent intra- and interlaboratory reproducibility was shown with concordance >98% and kappas >0.95. OncoPredict HPV® SCR fulfills the three international validation criteria for hrHPV DNA tests in cervical cancer screening.     

How are the cardiomyocytes aggregated together within the walls of the left ventricular cone?

The manner of packing together of the cardiomyocytes within the walls of the cardiac ventricles has now been investigated for over half a millennium. In 1669, Lower dissected the ventricular mass, likening the arrangement to skeletal musculature, in the form of a myocardial band extending between the right and left atrioventricular junctions. Pettigrew subsequently showed obvious helical arrangements to be evident within the ventricular walls, but emphasised that the cardiomyocytes were attached to each other, and could not justifiably be compared with skeletal cardiomyocytes. Torrent‐Guasp then reactivated the notion that the ventricular mass was formed of a solitary band. Unlike Lower, he dissected the band as extending between the pulmonary to the aortic roots. Multiple investigations conducted using gross dissection and histology, and more recently diffusion tensor magnetic resonance imaging and computed tomographic analysis, have shown an absence of any anatomical boundaries within the walls that might permit the mass uniformly to be dissected so as to reveal the band. A response to a recent letter to the Journal, nonetheless, claimed that the dissections had been validated by clinicians interpreting the findings so as to provide an explanation for ventricular cardiodynamics, arguing that the findings provided a suitable anatomical model for this purpose. Anatomical models, however, are of no value unless they are anatomically correct. In this review, therefore, we summarise the evidence showing that the cardiomyocytes making up the ventricular walls, rather than forming a ventricular myocardial band, are instead aggregated together to form a three‐dimensional myocardial mesh.     

The replication of the association of the rs9355610 within 6p27 with Graves’ disease

Abstract

The etiology of the autoimmune thyroid diseases (AITDs), Graves’ disease (GD) and Hashimoto’s thyroiditis (HT) is largely unknown. However, genetic susceptibility is believed to play a major role. Recently, Chu et al. conducted a genome-wide association study in a Chinese Han population and identified two novel GD susceptibility loci within 4p14 (rs6832151) and 6q27 (rs9355610). The objective of the study was to replicate these associations in a Japanese population. We analyzed rs6832151 and rs9355610 genotypes in a case-control study based on 457 Japanese AITD patients (286 GD and 171 HT patients) and 222 matched Japanese controls using the high-resolution melting and unlabeled probe methods. Case-control association studies were performed using the c² and Fisher’s exact tests with Yates correction. We found a significant allelic association between AITD and rs9355610 located in 6q27 (p?=?0.023). GD was significantly associated with this SNP (p?=?0.0055), while HT showed no significant associations with any SNPs. Moreover, when patients with GD were stratified according to Graves’ ophthalmopathy (GO), there were no allelic associations with GO. These findings suggest the presence of AITD susceptibilty genes, especially in distinct subgroups of GD, in or near 6q27.     

Determinants of the voltage dependence of G protein modulation within calcium channel β subunits

Ca_Vβ subunits of voltage-gated calcium channels contain two conserved domains, a src-homology-3 (SH3) domain and a guanylate kinase-like (GK) domain with an intervening HOOK domain. We have shown in a previous study that, although Gβγ-mediated inhibitory modulation of Ca_V2.2 channels did not require the interaction of a Ca_Vβ subunit with the Ca_Vα1 subunit, when such interaction was prevented by a mutation in the α1 subunit, G protein modulation could not be removed by a large depolarization and showed voltage-independent properties (Leroy et al., J Neurosci 25:6984–6996, 2005). In this study, we have investigated the ability of mutant and truncated Ca_Vβ subunits to support voltage-dependent G protein modulation in order to determine the minimal domain of the Ca_Vβ subunit that is required for this process. We have coexpressed the Ca_Vβ subunit constructs with Ca_V2.2 and α₂δ-2, studied modulation by the activation of the dopamine D2 receptor, and also examined basal tonic modulation. Our main finding is that the Ca_Vβ subunit GK domains, from either β1b or β2, are sufficient to restore voltage dependence to G protein modulation. We also found that the removal of the variable HOOK region from β2a promotes tonic voltage-dependent G protein modulation. We propose that the absence of the HOOK region enhances Gβγ binding affinity, leading to greater tonic modulation by basal levels of Gβγ. This tonic modulation requires the presence of an SH3 domain, as tonic modulation is not supported by any of the Ca_Vβ subunit GK domains alone. Andriy V. Dresviannikov and Karen M. Page contributed equally to this work.     

Microfluidic Platforms for Studies of Angiogenesis,Cell Migration,and Cell–Cell Interactions

Recent advances in microfluidic technologies have opened the door for creating more realistic in vitro cell culture methods that replicate many aspects of the true in vivo microenvironment. These new designs (i) provide enormous flexibility in controlling the critical biochemical and biomechanical factors that influence cell behavior, (ii) allow for the introduction of multiple cell types in a single system, (iii) provide for the establishment of biochemical gradients in two- or three-dimensional geometries, and (iv) allow for high quality, time-lapse imaging. Here, some of the recent developments are reviewed, with a focus on studies from our own laboratory in three separate areas: angiogenesis, cell migration in the context of tumor cell-endothelial interactions, and liver tissue engineering.     

Polymorphism within the nuclear and 2μm genomes of Saccharomyces cerevisiae

Summary Seven strains of bakers' yeast were obtained as a representative sample of the Spanish baking industry. The nuclear genome was monitored for polymorphism by transverse alternating field electrophoresis (TAFE) and restriction maps of 2 m DNA were produced. All seven strains were uniquely different when evaluated by their total chromosomal lengths whereas only two 2 m variants were defined. There was no apparent correlation between chromosomal and plasmid polymorphism. The extensive chromosomal polymorphism within one 2 m DNA type indicates the rapid and relatively recent evolution of the nuclear genome. The hybrid origin (S. cerevisiae-S.monacensis) of lager yeast was critically evaluated by TAFE analysis of S. cerevisiae and S. carlsbergensis chromosomes. The absence of corresponding S. cerevisiae chromosomes III and XIII in S. carlsbergensis argued against the hybrid origin of lager strains. We discuss limitations of the hybrid origin hypothesis of industrial yeasts and propose that the molecular coevolution observed in 2 m DNA serves as a useful additional mechanism for rationalization of some of the structural polymorphism of the nuclear genome.     

Genetic characterization of Tribeč virus and Kemerovo virus, two tick-transmitted human-pathogenic Orbiviruses

We determined the complete genome sequences of Tribe? virus (TRBV) and Kemerovo virus (KEMV), two tick-transmitted Orbiviruses that can cause diseases of the central nervous system and that are currently classified into the Great Island virus serogroup. VP2 proteins of TRBV and KEMV show very low sequence similarity to the homologous VP4 protein of tick-transmitted Great Island virus (GIV). The new sequence data support previous serological classification of these Orbiviruses into the Kemerovo serogroup, which is different from the Great Island virus serogroup. Genome segment 9 of TRBV and KEMV encodes several overlapping ORF's in the +1 reading frame relative to VP6(Hel). A co-phylogenetic analysis indicates a host switch from insect-borne Orbiviruses toward Ixodes species, which is in disagreement with previously published data.     

The role of serotonin within the microbiota-gut-brain axis in the development of Alzheimer’s disease: A narrative review

Alzheimer’s disease (AD) is the most common cause of dementia, accounting for more than 50 million patients worldwide. Current evidence suggests the exact mechanism behind this devastating disease to be of multifactorial origin, which seriously complicates the quest for an effective disease-modifying therapy, as well as impedes the search for strategic preventative measures. Of interest, preclinical studies point to serotonergic alterations, either induced via selective serotonin reuptake inhibitors or serotonin receptor (ant)agonists, in mitigating AD brain neuropathology next to its clinical symptoms, the latter being supported by a handful of human intervention trials. Additionally, a substantial amount of preclinical trials highlight the potential of diet, fecal microbiota transplantations, as well as pre- and probiotics in modulating the brain’s serotonergic neurotransmitter system, starting from the gut. Whether such interventions could truly prevent, reverse or slow down AD progression likewise, should be initially tested in preclinical studies with AD mouse models, including sufficient analytical measurements both in gut and brain. Thereafter, its potential therapeutic effect could be confirmed in rigorously randomized controlled trials in humans, preferentially across the Alzheimer’s continuum, but especially from the prodromal up to the mild stages, where both high adherence to such therapies, as well as sufficient room for noticeable enhancement are feasible still. In the end, such studies might aid in the development of a comprehensive approach to tackle this complex multifactorial disease, since serotonin and its derivatives across the microbiota-gut-brain axis might serve as possible biomarkers of disease progression, next to forming a valuable target in AD drug development. In this narrative review, the available evidence concerning the orchestrating role of serotonin within the microbiota-gut-brain axis in the development of AD is summarized and discussed, and general considerations for future studies are highlighted.