Genetic and Environmental Determinants of Variation of Soluble Adhesion Molecules

In our research we examined the contribution of putative genetic sources on interindividual variation and cross-sectional correlations of several adhesion molecules, including intracellular (ICAM-1) and vascular cell adhesion molecules (VCAM-1) and E-selectin, in a population-based sample of ethnically homogeneous families of European origin. The plasma levels of these molecules were measured in 947 apparently healthy individuals from 217 nuclear families. Quantitative statistical-genetic analysis implementing the model fitting technique revealed significant parent/offspring and sibling correlations (p < 0.01) for all three molecules. The putative genetic effects explained 55.2 ± 7.2% (VCAM-1), 63.3 ± 7.5% (ICAM) and 63.8 ± 8.1% (E-selectin) of the variation. Common family environmental factors also significantly influenced the variation of E-selectin (13%) and VCAM-1 (28.6%). The main results of our bivariate analysis showed that the observed phenotypic correlations between ICAM-1 and VCAM-1, and between ICAM-1 and E-selectin, were mostly attributable to shared environmental factors (  r_E= 0.896  and 0.737, respectively; p < 0.01). However, the correlation between VCAM-1 and E-selectin was likely caused by common genetic effects  (r_G= 0.334, p < 0.05)  . Our results show that familial clustering of adhesion molecules is likely due to strong genetic effects, supplemented with shared environmental factors.     

SWAP-70-like adapter of T cells,an adapter protein that regulates early TCR-initiated signaling in Th2 lineage cells

We describe the isolation of a protein, SWAP-70-like adapter of T cells (SLAT), which is expressed at high levels in thymocytes and differentiated Th2 cells. SLAT expression was upregulated in differentiating Th2 cells and downregulated in Th1 cells. Ectopic SLAT expression exerted positive or negative effects on IL-4 versus IFNgamma induction, respectively. TCR signaling induced translocation of SLAT to the immunological synapse and its association with ZAP-70 kinase. SLAT reduced the association of ZAP-70 with TCR-zeta and interfered with ZAP-70 but not Lck signaling. Consistent with these results, pharmacological inhibition of ZAP-70 also induced Th2 skewing. Thus, SLAT is a protein which plays a role in Th2 development and/or activation, perhaps by interfering with ZAP-70 signaling.     

EMAS position statement: Managing obese postmenopausal women

Introduction

Obesity is a public health problem, with overweight individuals representing approximately 20% of the adult world population. Postmenopausal status is associated with higher prevalence of obesity, as 44% of postmenopausal women are overweight, among whom 23% are obese. Obesity often co-exists with other diseases, the most important being diabetes mellitus, dyslipidemia and hypertension. Furthermore, obesity increases the risk of gynecologic cancer, cardiovascular disease, venous thromboembolism, osteoarthritis and chronic back pain.

Aim

To formulate a position statement on the management of the menopause in obese women.

Materials and methods

Literature review and consensus of expert opinion.

Results and conclusions

Obese women seeking hormone therapy should be evaluated for their individual baseline risk of developing breast cancer, cardiovascular disease and venous thromboembolism. These risks should be weighed against expected benefit from symptom relief, improved quality of life and osteoporosis prevention. The lowest effective estrogen dose should be used (CEE 0.300–0.400 mg or estradiol 0.5–1 mg orally daily or 25–50 μg estradiol transdermally). With regard to progestogens, although no RCT data exist, there are observational studies showing that micronized progesterone or dydrogesterone may have a better risk profile with respect to breast cancer risk. There are no RCT data comparing various progestogens with regard to VTE risk. There are observational data, however, suggesting that micronized progesterone or pregnane derivatives may be associated with a lower VTE risk in postmenopausal women taking HT compared to nonpregnane derivatives. There is a rationale in suggesting the use of transdermal HT in obese women, since this route of administration has been associated with a lesser risk of venous thromboembolism than oral therapy.     

ATP depletion inhibits Ca2+ release, influx and extrusion in pancreatic acinar cells but not pathological Ca2+ responses induced by bile

Here, we describe novel mechanisms limiting a toxic cytosolic Ca²⁺ rise during adenosine 5′-triphosphate (ATP) depletion. We studied the effect of ATP depletion on Ca²⁺ signalling in mouse pancreatic acinar cells. Measurements of ATP in isolated cells after adenovirus-mediated expression of firefly luciferase revealed that the cytosolic ATP concentration fell from approximately 1 mM to near zero after treatment with oligomycin plus iodoacetate. ATP depletion resulted in the inhibition of Ca²⁺ extrusion, which was accompanied by a remarkably synchronous inhibition of store-operated Ca²⁺ influx. Alternative inhibition of Ca²⁺ extrusion by carboxyeosin had a much smaller effect on Ca²⁺ influx. The coordinated metabolic inhibition of Ca²⁺ influx and extrusion suggests the existence of a common ATP-dependent master regulator of both processes. ATP-depletion also suppressed acetylcholine (ACh)-induced Ca²⁺ oscillations, which was due to the inhibition of Ca²⁺ release from internal stores. This could be particularly important for limiting Ca²⁺ toxicity during periods of hypoxia. In contrast, metabolic control of Ca²⁺ influx and Ca²⁺ release from internal stores spectacularly failed to prevent large toxic Ca²⁺ responses induced by bile acids—activators of acute pancreatitis (a frequent and often fatal disease of the exocrine pancreas). The bile acids taurolithocholic acid 3-sulphate (TLC-S), taurochenodeoxycholic acid (TCDC) and taurocholic acid (TC) were used in our experiments. Neither Ca²⁺ release from internal stores nor Ca²⁺ influx triggered by bile acids were inhibited by ATP depletion, emphasising the danger of these pathological mechanisms. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

CD28 costimulation is critical for experimental allergic asthma in HLA-DQ8 transgenic mice

The objective of this study was to investigate the contribution of the CD28 costimulatory molecules to allergen-induced primary and chronic inflammatory responses. To this end, we have developed and characterized a short ragweed allergen-induced asthma model involving sensitization of HLA-DQ transgenic mice followed by intranasal challenge with allergen. Forty-eight hours after primary challenge, sensitized DQ8 mice developed pulmonary eosinophilic inflammation, airway hyperreactivity, Th2 cytokines, and IgE/IgG1 Ab. This allergic inflammatory response was absent in H-2Abeta(0) and DQ8/CD28(0) mice. Secondary rechallenge with allergen 4 weeks later induced even greater inflammatory changes in the airways of DQ8 mice with eosinophils being the predominant inflammatory cells while only pulmonary lymphocytosis was observed in DQ8/CD28(0) mice. No inflammation was detected in H-2Abeta(0) mice. Proliferation and cytokine profile studies demonstrated that CD28 regulates T-cell activation and effector function. Therefore, CD28 is essential for the extrinsic asthma and can be a target for immunotherapy.     

Glycosylphosphatidylinositol (GPI) anchored protein deficiency serves as a reliable reporter of Pig‐a gene Mutation: Support from an in vitro assay based on L5178Y/Tk+/− cells and the CD90.2 antigen

Lack of cell surface glycosylphosphatidylinositol (GPI)‐anchored protein(s) has been used as a reporter of Pig‐a gene mutation in several model systems. As an extension of this work, our laboratory initiated development of an in vitro mutation assay based on the flow cytometric assessment of CD90.2 expression on the cell surface of the mouse lymphoma cell line L5178Y/Tk^+/?. Cells were exposed to mutagenic and nonmutagenic compounds for 24 hr followed by washout and incubation for an additional 7 days. Following this mutant manifestation time, cells were labeled with fluorescent antibodies against CD90.2 and CD45 antigens. These reagents indicated the presence of GPI‐anchored proteins and general cell surface membrane receptor integrity, respectively. Instrument set‐up was aided by parallel processing of a GPI anchor‐deficient subclone. Results show that the mutagens reproducibly caused increased frequencies of mutant phenotype cells, while the nonmutagens did not. Further modifications to the method, including application of a viability dye and an isotype control for instrument set‐up, were investigated. As a means to verify that the GPI‐anchored protein‐negative phenotype reflects bona fide Pig‐a gene mutation, sequencing was performed on 38 CD90.2‐negative L5178Y/Tk^+/? clones derived from cultures treated with ethyl methanesulfonate. All clones were found to have mutation(s) within the Pig‐a gene. The continued investigation of L5178Y/Tk^+/? cells, CD90.2 labeling, and flow cytometric analysis as the basis of an in vitro mutation assay is clearly supported by this work. These data also provide evidence of the reliability of using GPI anchor‐deficiency as a valid reporter of Pig‐a gene mutation. Environ. Mol. Mutagen. 59:18–29, 2018. © 2017 Wiley Periodicals, Inc.     

Word onset phonetic properties and motor artifacts in speech production EEG recordings

Electrophysiological research using verbal response paradigms faces the problem of muscle artifacts that occur during speech production or in the period preceding articulation. In this context, this paper has two related aims. The first is to show how the nature of the first phoneme influences the alignment of the ERPs. The second is to further characterize the EEG signal around the onset of articulation, both in temporal and frequency domains. Participants were asked to name aloud pictures of common objects. We applied microstate analyses and time‐frequency transformations of ERPs locked to vocal onset to compare the EEG signal between voiced and unvoiced labial plosive word onset consonants. We found a delay of about 40 ms in the set of stable topographic patterns for /b/ relative to /p/ onset words. A similar shift was observed in the power increase of gamma oscillations (30–50 Hz), which had an earlier onset for /p/ trials (～150 ms before vocal onset). This 40‐ms shift is consistent with the length of the voiced proportion of the acoustic signal prior to the release of the closure in the vocal responses. These results demonstrate that phonetic features are an important parameter affecting response‐locked ERPs, and hence that the onset of the acoustic energy may not be an optimal trigger for synchronizing the EEG activity to the response in vocal paradigms. The indexes explored in this study provide a step forward in the characterization of muscle‐related artifacts in electrophysiological studies of speech and language production.     

Suppression of Mamu-AG by RNA Interference

Problem  The role of placental major histocompatibility complex (MHC) class I molecules in pregnancy is not well understood. Mamu-AG, the rhesus monkey homology of human leukocyte antigen (HLA)-G expressed in the human placenta, was targeted for degradation by RNA interference (RNAi), a powerful tool to aid in determining gene function, to determine the effect that this knockdown has on NK cell function.
Method of study  A series of potential target short hairpin RNA (shRNA) sequences to suppress Mamu-AG expression was screened, which identified an optimal sequence to use in transfection experiments. Knockdown in two different Mamu-AG-expressing cell lines was measured by flow cytometry. Cytotoxicity assays were performed to correlate Mamu-AG expression with NK cell cytotoxicity.
Results  Decreased expression of Mamu-AG by short interfering RNA (siRNA) (70–80%) in cell types tested was associated with increased lysis of Mamu-AG target cells.
Conclusion  Target sequences have been identified that knocked down Mamu-AG expression by RNAi and increased lysis by NK cells. This supports the concept that NK cell receptors recognize this placental non-classical MHC class I molecule.