Progression of Alzheimer's disease and effect of scFv-h3D6 immunotherapy in the 3xTg-AD mouse model: An in vivo longitudinal study using Magnetic Resonance Imaging and Spectroscopy

Alzheimer's disease (AD) is an incurable disease that affects most of the 47 million people estimated as living with dementia worldwide. The main histopathological hallmarks of AD are extracellular β-amyloid (Aβ) plaques and intracellular neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau protein. In recent years, Aβ-immunotherapy has been revealed as a potential tool in AD treatment. One strategy consists of using single-chain variable fragments (scFvs), which avoids the fragment crystallizable (Fc) effects that are supposed to trigger a microglial response, leading to microhemorrhages and vasogenic edemas, as evidenced in clinical trials with bapineuzumab. The scFv-h3D6 generated by our research group derives from this monoclonal antibody, which targets the N-terminal of the Aβ peptide and recognizes monomers, oligomers and fibrils. In this study, 3xTg-AD mice were intraperitoneally and monthly treated with 100 μg of scFv-h3D6 (a dose of ~3.3 mg/kg) or PBS, from 5 to 12 months of age (-mo), the age at which the mice were sacrificed and samples collected for histological and biochemical analyses. During treatments, four monitoring sessions using magnetic resonance imaging and spectroscopy (MRI/MRS) were performed at 5, 7, 9, and 12 months of age. MRI/MRS techniques are widely used in both human and mouse research, allowing to draw an in vivo picture of concrete aspects of the pathology in a non-invasive manner and allowing to monitor its development across time. Compared with the genetic background, 3xTg-AD mice presented a smaller volume in almost all cerebral regions and ages examined, an increase in both the intra and extracellular Aβ_1-42 at 12-mo, and an inflammation process at this age, in both the hippocampus (IL-6 and mIns) and cortex (IL-6). In addition, treatment with scFv-h3D6 partially recovered the values in brain volume, and Aβ, IL-6, and mIns concentrations, among others, encouraging further studies with this antibody fragment.

Abstract P2-03-09: Comparison of the mutational landscape of breast cancer during pregnancy and non-pregnant controls

Background:Currently, breast cancer during pregnancy (BCP) is not believed to be biologically different from breast cancer unrelated to pregnancy based on limited datasets mainly obtained by immunohistochemistry. However, some groups report that BCP patients have an inferior survival compared to young non-pregnant breast cancer patients. The largest analysis based on the BCP registry by the German Breast Group (GBG) revealed however, no difference between pregnant and non-pregnant breast cancer patients, indicating that treatment rather than biology might be the reason for the inferior survival reported by others.

Methods: The BCP study (GBG 29/BIG 03-02) is a multicentre observational study for breast cancer during pregnancy. In tumour tissue collected within this study from pregnant M0 patients we investigated the following genes: AKT1, ATM, BRAF, CBFB, CCND1, CDH1, CDKN2A, CTCF, EGFR, ERBB2, ESR1, FGFR2, GATA3, KRAS, MAP2K4, MAP3K1, MDM2, MED12, MYC, PIK3CA, PIK3R1, PTEN, RB1, RUNX1, and TP53 by massive parallel sequencing (MPS). This included patients with all molecular subtypes: HR+/-, HER2+/-. Sequencing was done on an IonTorrent Proton using a custom designed Breast Cancer Panel (BCPv2). This panel comprises 236 amplicons split into two primer pools and covers hotspot regions of 138 exons of the 25 genes.

To test the hypothesis that breast cancer diagnosed during pregnancy is biologically not different from breast cancer diagnosed in young non-pregnant women, we compared the molecular profiles obtained, with genetic data from M0 patients not known to be pregnant from TCGA with age <= 45. TCGA data were pre-processed to be compatible to the targeted MPS datasets from pregnant patient.

Results: Material from 141 patients from the BCP study was available from which ultimately 109 fully evaluable MPS datasets could be obtained. In the TCGA data set 114 breast cancer patients <= 45 years could be identified. Pregnant patients with breast cancer were significantly younger, had more often HR- tumours (59.6% vs 30.1%) but had less frequently grade 3 tumours (30.6% vs 48.2%). All other clinical variables showed no significant differences between pregnant and non-pregnant patients. In the BCP data, overall 106 mutations could be found. The most frequent mutations were detected in TP53 (62%) and in PIK3CA (11.1%). In non-pregnant patients the mutation rates were different with 32.5% in TP53 and 21.1% in PIK3CA.

Exact matching by variables age, HR, HER2 and grade yielded 40 patients from both datasets. In these subcohorts, still divergent mutational rates for TP53 and PIK3CA between pregnant and non-pregnant women were noted, however, the differences failed to reach statistical significance.

Conclusions: Overall the mutational landscapes do not seem to be overtly different between pregnant patients and no-pregnant controls, although slight imbalances in mutational rates occurred, which might be partly explained by a selection bias and a small sample size after matching. Further comparisons using other datasets, looking into survival and regarding copy number variation are currently conducted.

This research is been funded by the German Cancer Consortium-DKTK and the BANSS Foundation.

Citation Format: Loibl S, Pfarr N, Weber K, Neunhöffer T, Villegas S, Stenzinger A, Furlanetto J, Aktas B, Budczies J, Marmé F, Kahmann L, Denkert C, Weichert W. Comparison of the mutational landscape of breast cancer during pregnancy and non-pregnant controls [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-03-09.

3% Hypertonic Saline Versus Normal Saline in Inpatient Bronchiolitis: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Bronchiolitis, the most common reason for hospitalization in children younger than 1 year in the United States, has no proven therapies effective beyond supportive care. We aimed to investigate the effect of nebulized 3% hypertonic saline (HS) compared with nebulized normal saline (NS) on length of stay (LOS) in infants hospitalized with bronchiolitis.

METHODS

We conducted a prospective, randomized, double-blind, controlled trial in an urban tertiary care children's hospital in 227 infants younger than 12 months old admitted with a diagnosis of bronchiolitis (190 completed the study); 113 infants were randomized to HS (93 completed the study), and 114 to NS (97 completed the study). Subjects received 4 mL nebulized 3% HS or 4 mL 0.9% NS every 4 hours from enrollment until hospital discharge. The primary outcome was median LOS. Secondary outcomes were total adverse events, subdivided as clinical worsening and readmissions.

RESULTS

Patient characteristics were similar in groups. In intention-to-treat analysis, median LOS (interquartile range) of HS and NS groups was 2.1 (1.2-4.6) vs 2.1 days (1.2-3.8), respectively, P = .73. We confirmed findings with per-protocol analysis, HS and NS groups with 2.0 (1.3-3.3) and 2.0 days (1.2-3.0), respectively, P = .96. Seven-day readmission rate for HS and NS groups were 4.3% and 3.1%, respectively, P = .77. Clinical worsening events were similar between groups (9% vs 8%, P = .97).

CONCLUSIONS

Among infants admitted to the hospital with bronchiolitis, treatment with nebulized 3% HS compared with NS had no difference in LOS or 7-day readmission rates.

[Birth weight and later nutritional status, cognitive development and job status: a critical revision]

The impact of prenatal nutritional status, assessed through birth weight (BW) and their effects in the short, medium and long-term on nutritional status, cognitive development and job status in the adult life, has been a problem of interest for several researchers; as regards, some of these report a positive and significant association between these variables and others do not find any relation. Children with insufficient, low or very low BW despite the early more deteriorate nutritional status should present higher risk for brain maturation, failure cognitive development and lowered head circumference which implies both lowered brain volume and intellectual development. In the short and medium-term, this situation damages the learning process at school-age, while in the long-term this might condition the quality of jobs. At present, the body of knowledge pinpoints that findings related to these associations is not conclusive verifying a great controversy in these matters. This review article has the purpose of analyzing the current evidence, in order to stimulate research about to these aspects which are relevant for child development and their future life.

Comparative study of the dissolution profiles of a commercial theophylline product after storage

The purpose of this work was to study the effect of storage time and temperature on the in vitro release kinetics of a commercial sustained-release dosage form of theophylline, at different pHs of the dissolution medium. The formulation was stored at 35 degrees C for 16 months and at 45 degrees C for 8 months, with a relative humidity of 60%. The in vitro release tests were performed at pHs 2, 4, 6 and 7.4. The mean values of the transport coefficient n, were close to 0.5 in all the conditions tested, which indicates that the transport system is not modified after storage of the formulation at 35 degrees C and 45 degrees C. The mean values of the dissolution rate constant ranged from 0.036 to 0.043 min(-n), under all the conditions tested. Significant differences (alpha = 0.05) were found between pHs 2, 4 and 6, 7.4 for all the model-independent parameters studied. When the formulation was kept at 35 degrees C for 16 months, the mean percentage of drug dissolved at 8 hours was 25.61% (pHs 2, 4) and, 36.12% (pHs 6, 7.4), representing a 26% and 24% reduction, respectively. Similar results were obtained after storing the formulation at 45 degrees C for 8 months, corresponding to 33.3% (pHs 2, 4) and, 22.5% (pHs 6, 7.4) diminution, respectively. The values of the similarity factor, f2, obtained were lower than 50, which indicates the lack of similarity among the dissolution profiles, after storing the formulation under the experimental conditions tested.

Thyroid hormone-induced stimulation of the sarcoplasmic reticulum Ca(2+) ATPase gene is inhibited by LIF and IL-6

We investigated the effects of the leukemia inhibitory factor (LIF) and interleukin-6 (IL-6) on 3,3', 5-triiodo-L-thyronine, or thyroid hormone (T(3))-stimulated sarcoplasmic reticulum Ca(2+) ATPase (SERCA2) gene expression on cultured neonatal rat cardiac myocytes. A reduction of T(3) induced increases in SERCA2 mRNA levels after co-treatment with LIF or IL-6. To investigate for the molecular mechanism(s) responsible for the blunted gene expression, a 3.2-kb SERCA2 promoter construct containing a reporter gene was transfected into cardiac myocytes. T(3) treatment stimulated transcriptional activity twofold, whereas co-treatment with T(3) and either of the cytokines caused an inhibition of T(3)-induced SERCA2 transcriptional activity. A T(3)-responsive 0.6-kb SERCA2 construct also showed a similar inhibition by cytokines. Cytokine inhibition of SERCA2 transcriptional activity was also evident when a 0.6-kb SERCA2 mutant, T(3)-unresponsive promoter construct was used. Treatment with T(3) and cytokines showed a significant decrease in transcription when a reporter construct was used that was comprised of direct repeats of SERCA2 thyroid response element I. These data provide evidence for cytokine-mediated inhibitory effects on the SERCA2 promoter that may be mediated by interfering with T(3) action.

Leukemia Inhibitory Factor and Interleukin-6 downregulate sarcoplasmic reticulum Ca2+ ATPase (SERCA2) in cardiac myocytes

Alterations in gene expression are a hallmark of cardiac hypertrophy and heart failure. Among these, the decreased expression of the sarcoplasmic reticulum calcium ATPase (SERCA2) has been described. Elevated levels of cytokines in particular, Leukemia Inhibitory Factor (LIF) and Interleukin-6 (IL-6) have been shown to have the capacity to elicit hypertrophic responses in cultured cardiac myocytes. In this study, we investigated the effects of these cytokines (LIF & IL-6) on the regulation of SERCA2 levels in cardiac myocytes. Cultured neonatal rat ventricular myocytes were transfected with a 3.2 kb promoter plasmid construct containing the SERCA2 promoter linked to a chloramphenicol acetyltransferase (CAT) reporter gene, and subsequently treated with 10 ng/ml LIF or 10 ng/ml IL-6. LIF and IL-6 independently caused a significant (p < or = 0.05) 23-36% inhibition in SERCA2 promoter activity. LIF and IL-6 induced inhibition was also evident in SERCA2 mRNA levels as assessed by Northern analysis. Time course of inhibition of SERCA2 mRNA levels showed the most prominent decrease occurring after 48 hours of treatment, with both cytokines having a dose dependent effect on the inhibitory response. Western analysis using a polyclonal antibody to SERCA2 protein indicate a significant, 60% decrease in the amount of total SERCA2 protein in cultured myocytes treated with 10 ng/ml LIF or IL-6. In conclusion, the cytokines LIF and IL-6 downregulate SERCA2 gene expression and protein levels. The molecular mechanism responsible for cytokine induced downregulation of SERCA2 is at least partly transcriptional.

Identification of G protein-coupled signaling pathways in cardiac fibroblasts: cross talk between G(q) and G(s)

Cardiac fibroblasts (CFs) are an important cellular component of myocardial responses to injury and to hypertrophic stimuli. We studied G protein-coupled receptors to understand how CFs integrate signals that activate G(q), G(s), and G(i). We predicted that the second messenger pathways present in CFs were distinct from those in cardiac myocytes and that unique signaling interactions existed in the CFs. ANG II, bradykinin, ATP, and UTP stimulated inositol phosphate (IP) production 2.2- to 7-fold. Each of these agonists elevated intracellular Ca(2+) concentration ([Ca(2+)](i)) via release from the intracellular Ca(2+) storage compartment. Endothelin-1 (ET-1), carbachol, and norepinephrine failed to increase either IP production or [Ca(2+)](i). Although agonists that activated IP and Ca(2+) transients had no effect on cAMP production when administered alone, these agents potentiated the beta(2)-adrenergic response two- to fourfold. Hormones known to inhibit adenylyl cyclase activity in cardiac myocytes, such as ET-1 and carbachol, failed to lower the beta-adrenergic response in fibroblasts. Order of potency and inhibitor data indicate that the functional receptor subtypes in these cells are beta(2), P2Y(2), and AT(1) for isoproterenol, ATP, and ANG II, respectively. We conclude that CFs express functional G protein-linked receptors that couple to G(q) and G(s), with little or no coupling to G(i). The expression of receptors and their coupling to G(q)- but not to G(i)-linked responses distinguishes the signaling in CFs from that in myocytes. Furthermore, agonists that activate G(q) in CFs potentiate stimulation of G(s), an example of signaling cross talk not observed in adult myocytes. These data suggest that G protein-mediated signaling in CFs is unique and may contribute to the specificity of hormone and drug action on individual cell types within the heart.

Evaluation of a fluorescence-polarization assay for the diagnosis of bovine brucellosis in México

A homogeneous fluorescence-polarization assay (FPA) was used for the serological diagnosis of bovine brucellosis in México. The assay uses O-polysaccharide prepared from Brucella abortus lipoplysaccharide (20-30 kDa) conjugated with fluorescein isothiocyanate as a tracer. To measure the fluorescence polarization, a FPM-1 fluorescence-polarization analyzer was used with the procedure described by Nielsen et al. (1996b). A cut-off value of 90 millipolarization (mP) units was used for testing 560 bovine sera from different areas of México. (305 positive sera and 255 negative sera according to the complement fixation test; CFT.) Some were tested with the Rose Bengal plate (RB) test (n = 490) and some with the rivanol-agglutination (RIV) test (n = 190). Sensitivities were 98.3%, 99.3% and 99.0%, and specificities were 68.8%, 55.4% and 96.9%, respectively, for RB, RIV and FPA. The FPA gave a kappa coefficient of agreement with respect to CFT of 0.96, while RB and RIV (relative to the CFT) gave coefficients of 0.70 and 0.61, respectively. Finally, ROC analysis suggested a cut-off value which agreed with the one recommended in the test procedure. We concluded that FPA is a suitable test to be used instead of the CFT in Mexican conditions.

Regulation of cardiac fibroblast extracellular matrix production by bradykinin and nitric oxide

The beneficial effects of angiotensin-converting enzyme inhibitors on ameliorating cardiac fibrosis have been partially attributed to their ability to prevent the degradation of kinins. The potential role of bradykinin and the related signaling molecule nitric oxide (NO) in modulating extracellular matrix (ECM) production was examined in primary cultures of adult rat cardiac fibroblasts. Treatment of fibroblasts with 5 nM bradykinin for 24 h led to a reduction in steady-state mRNA levels for fibronectin (34 +/- 7%) and collagens type I (19 +/- 8%) and type III (48 +/- 4%), as determined by Northern blot analysis. The NO synthase inhibitor L-NAME attenuated the reduction observed in fibronectin and collagen mRNA levels in response to bradykinin. The NO donor DETA NONOate (100 microM) mimicked the effects of bradykinin on ECM mRNA levels. Protein levels of soluble fibronectin, assessed in conditioned medium by ELISA, were decreased by 14 +/- 4% and 21 +/- 4% after 48 h treatment with 1 microM bradykinin and 100 microM DETA NONOate, respectively. Bradykinin stimulated intracellular cGMP accumulation 73.7 +/- 10.3% after 10 min of treatment. Cell proliferation rates at 48 h were unaffected by bradykinin, but were reduced by 26 +/- 12% by 100 microM DETA NONOate. These data indicate that bradykinin downregulates ECM protein production in cardiac fibroblasts and suggest that NO and the related signaling molecule cGMP may play an important role in mediating this response.

Cardiac fibroblasts arrest at the G1/S restriction point in response to interleukin (IL)-1beta. Evidence for IL-1beta-induced hypophosphorylation of the retinoblastoma protein

Although responsible for only approximately one-third of the overall myocardial mass, the interstitial fibroblasts of the heart serve a fundamental role in establishing the functional integrity of myocardium and are the major source of myocardial extracellular matrix production. Their importance in clinical medicine is underscored by the observation that fibroblast numbers increase in response to several pathologic circumstances that are associated with an increase in extracellular matrix production, such as long standing hypertension and myocardial injury/infarction. Up to the present time, however, there has been little information available on either the kinetics of the cardiac fibroblast cell cycle, or the fundamental mechanisms that regulate its entry into and exit from the cell cycle. Previous work from our laboratory examining the effects of interleukin (IL)-1beta on myocardial growth and gene expression in culture indicated that cardiac fibroblasts have a diminished capacity to synthesize DNA in response to mitogen in the presence of this cytokine. The mechanism of IL-1beta action was not clear, however, and could have resulted from action at several different points in the cell cycle. The investigations described in this report indicate that IL-1beta exerts its effect on the fibroblast cell cycle at multiple levels through altering the expression of cardiac fibroblast cyclins, cyclin-dependent kinases, and their inhibitors, which ultimately affect the phosphorylation of the retinoblastoma gene product.

Application of an immunoassay to determine risk factors associated with porcine cysticercosis in rural areas of Yucatan, Mexico

A Western blot assay for identification of 26 kDa and/or 8 kDa antigens in a crude saline extract (CSE) of Taenia solium metacestodes, previously developed for human cysticercosis, was evaluated for use with pigs. The test population used for assay standardisation consisted of 45 cysticercotic pigs (5 pigs positive by necropsy and 40 selected by tongue palpation and LL-Gp immunoblot but not confirmed by necropsy), 48 pigs with heterologous infections and 40 negative controls from endemic and non-endemic areas. The test detected 93% of the cysticercotic group and was 100% specific. In a field study this antigen preparation was compared by immunoblot with antibody recognition for Gp13-50 antigens in a lentil-lectin semi-purified glycoprotein extract of T. solium (LL-Gp). The seroprevalence to CSE antigen was slightly lower (26/75) when compared to LL-Gp (29/75) and this represented a non-significant difference. The CSE Western blot assay was used to assess seroprevalence of T. solium cysticercosis in pig populations in the state of Yucatan, Mexico. A total of 1099 pigs sampled at random from 25 villages revealed a seroprevalence of 23% (253/1099). Seroprevalence in intensively reared, farmed pigs was 2% (7/228). In comparison with farmed pigs, the seroprevalence was 33% (172/513) in free-roaming backyard pigs (OR=13.86, CI=4.0747.22, p<10(-6)) and 25% (74/98) in semi-confined backyard pigs (OR=14.03, CI=5.60-35.16, p<10(-6)). There was no significant difference in seroprevalence by sex (p=0.23). Seroprevalence decreased with age (chi(2)-test for linear trend=7.803, p<0.006). Results of this study demonstrate that the CSE Western blot can be applied for reliable immunodiagnosis of T. solium cysticercosis in pigs. Furthermore, variation in pig husbandry in Yucatan indicated significantly higher exposure to cysticercosis in free-roaming backyard pigs compared to intensively reared animals from the same area.

The quasi-irreversible nature of endothelin binding and G protein-linked signaling in cardiac myocytes

In experiments on neonatal and adult rat ventricular myocytes, endothelin (ET) binding and the effects of ET on transmembrane signaling are quasi-irreversible. The ET(A) receptor antagonist BQ123 competes for binding and biochemical effects if added simultaneously with ET; when added after ET, the antagonist prevents neither binding nor activation of the Gi and Gq pathways. At 4 degrees C, at which internalization of the ligand should be minimized, the interaction of [125I]ET is still irreversible. After binding of radio-labeled ligand at either 4 degrees C or 37 degrees C, only 50% of ligand is removed by acid washing. Permeabilization of the cells with Triton X-100 fails to release irreversibly bound ligand. Binding experiments in cell membranes mimic this irreversible binding. At 37 degrees C, the addition of mercaptoethanol or dithiothreitol inhibits concurrent ET binding but does not cause the dissociation of previously bound ligand or the reversal of previously activated signaling. We conclude that ET binds irreversibly to myocytes, that this irreversibility is reflected in the biochemical responses of the cells to ET and that the irreversibility is more complex than the formation of S-S bonds between surface receptors and ET or internalization of bound ET. We interpret these findings and others in the literature in light of a testable model of ET(A) receptor/G protein/effector interaction in which quasi-irreversible binding of ET to the ET(A) receptor occurs before the interaction of the ligand/receptor complex with G protein and in which irreversible binding contributes to the prolonged effects of ET and is a prelude to refractoriness and to the slow regeneration of free ET(A) receptor.

Endothelin ETA receptor regulates signaling and ANF gene expression via multiple G protein-linked pathways

We have characterized the interaction of endothelin (ET) with cultured neonatal rat ventricular myocytes. Binding studies indicate a single population of ETA receptors [53,000 sites/cell, apparent dissociation constant (Kd) for ET-1 approximately 0.07 nM]. Analysis of mRNA levels for ET receptors using 35 cycles of reverse transcriptase-polymerase chain reaction demonstrates the presence of only ETA-receptor message. Studies with ET-1 and a variety of congeners and antagonists indicate that ETA receptors couple to both the stimulation of phosphoinositide turnover and the inhibition of adenylyl cyclase. In myocytes transfected with an atrial natriuretic factor (ANF) promoter linked to a luciferase reporter gene, ET-1 stimulates luciferase expression through an ETA receptor. These data indicate that the ETA receptor is the exclusive receptor on neonatal ventricular myocytes and that this receptor couples to both phosphoinositide hydrolysis and adenylyl cyclase. ET-1 also induces a threefold increase in mitogen-activated protein kinase (MAPK) activity, an effect that is not sensitive to pertussis toxin (PTx). By contrast, ET-stimulated ANF-luciferase expression is partially inhibited by treatment of cells with PTx, suggesting that both PTx-sensitive (Gi) and PTx-insensitive (Gq) pathways mediate the effects of ET-1 on ANF gene expression in neonatal myocytes and that hormonal regulation of ANF expression may utilize pathways in addition to the activation of MAPK.