Real-time investigation of an influenza A(H3N2) virus outbreak in a refugee community, November 2022

OBJECTIVES

To report epidemiological and virological results of an outbreak investigation of influenza-like illness (ILI) among refugees in Northern Italy.

STUDY DESIGN

Outbreak investigation of ILI cases observed among nearly 100 refugees in Northern Italy unvaccinated for influenza.

METHODS

An epidemiological investigation matched with a differential diagnosis was carried out for each sample collected from ILI cases to identify 10 viral pathogens (SARS-CoV-2, influenza virus type A and B, respiratory syncytial virus, metapneumovirus, parainfluenza viruses, rhinovirus, enterovirus, parechovirus, and adenovirus) by using specific real-time PCR assays according to the Centers for Disease Control and Prevention (CDC) protocols. In cases where the influenza virus type was identified, complete hemagglutinin (HA) gene sequencing and the related phylogenetic analysis were conducted.

RESULTS

The outbreak was caused by influenza A(H3N2): the attack rate was 83.3% in children aged 9-14 years, 84.6% in those aged 15-24 years, and 28.6% in adults ≥25 years. Phylogenetic analyses uncovered that A(H3N2) strains were closely related since they segregated in the same cluster, showing both a high mean nucleotide identity (100%), all belonging to the genetic sub-group 3C.2a1b.2a.2, as those mainly circulating into the general population in the same period.

CONCLUSIONS

The fact that influenza outbreak strains as well as the community strains were genetically related to the seasonal vaccine strain suggests that if an influenza prevention by vaccination strategy had been implemented, a lower attack rate of A(H3N2) and ILI cases might have been achieved.

Speed of in vitro embryo development affects the likelihood of foaling and the foal sex ratio

The success of invitro embryo production (IVEP) in horses has increased considerably during recent years, but little is known about the effect of the speed of invitro embryo development. Blastocysts (n=390) were produced by intracytoplasmic sperm injection of IVM oocytes from warmblood mares, cryopreserved, thawed and transferred into recipient mares on Days 3, 4, 5 or 6 after ovulation. The time required for invitro-produced (IVP) embryos to reach the blastocyst stage was recorded (Day 7 vs Day 8). The likelihood of foaling was affected by the speed of invitro embryo development and recipient day after ovulation at transfer. The odds ratio for foaling was ~0.63 for transfer of Day 8 (46%) compared with Day 7 (56%) IVP blastocysts. The highest likelihood of pregnancy (72%) and foaling (60%) was observed when IVP blastocysts were transferred to recipient mares on Day 4 after ovulation. Finally, the sex (colt:filly) ratio was higher after transfer of Day 7 (71%:29%) than Day 8 (54%:46%) IVP blastocysts, suggesting that the speed of embryo development is sex dependent. In conclusion, the speed of invitro embryo development in our IVEP system affects the likelihood of foaling and the sex of the foal.

Serological diagnosis and prevalence of HIV-1 infection in Russian metropolitan areas

BACKGROUND

HIV infection is a major health problem in Russia. We aimed to assess HIV prevalence in different population groups and to compare the characteristics of 4th generation immunoassays from Abbott, Bio-Rad, Vector-Best, Diagnostic Systems, and Medical Biological Unit.

METHODS

The study included 4452 individuals from the general population (GP), 391 subjects at high risk of HIV infection (HR) and 699 with potentially interfering conditions. HIV positivity was confirmed by immunoblot and by HIV RNA, seroconversion and virus diversity panels were also used. HIV avidity was employed to assess recent infections.

RESULTS

The prevalence in GP was 0.40%, higher in males (0.62%) and in people aged < 40 years (0.58%). Patients attending dermo-venereal centers and drug users had a high prevalence (34.1 and 58.8%). Recent infections were diagnosed in 20% of GP and in 4.2% of HR. Assay sensitivity was 100% except for one false negative (99,54%, MBU). Specificity was 99.58-99.89% overall, but as low as 93.26% on HR (Vector-Best). Small differences on early seroconversion were recorded. Only the Abbott assay detected all samples on the viral diversity panel.

CONCLUSION

HIV infection rate in the high-risk groups suggests that awareness and screening campaigns should be enhanced. Fourth generation assays are adequate but performance differences must be considered.

Influenza surveillance system and Covid-19

The clinical presentation of symptomatic SARS-CoV-2 not only includes viral pneumonia, but also milder illness overlapping with influenza-like illness (ILI), allowing a potential tracking of the infection in the framework of the national influenza surveillance system (SS). By comparing the data recorded by the influenza SS in 2019-20 season to those collected for the previous years, we want to evaluate whether the implementation of ILI SS could succeed in early detection and monitoring of Covid-19 diffusion.

We analyzed the data recorded by the influenza SS and we compared the distribution of ILI incidence rate by week for 2017-18, 2018-19 and 2019-20 season in order to understand whether the SS detected any abnormality coinciding with Covid-19 outbreak.

The distribution of ILI cases in the three seasons presented a similar pattern up to the 9th week; after then, a reduction in the ILI incidence rate was observed in the 2017-18 and the 2018-19 season while an increase was detected for 2019-20. During 2019-20 season, three major characteristics stand out: i) at the beginning of Covid-19 epidemic (7th-9th week) 9,17/1000 cases were reported; ii) during the recognition of the COVID-19 outbreak (9th-10th week) 6,36/1000 cases; iii) during the spread of Covid-19 (10th-11th week) an unexpected increase to 7,72/1000 cases. Additionally, their geographical distribution was concentrated in the areas known to be most affected by the epidemic.

The influenza SS enabled us to detect the introduction and distribution of COVID-19. Implementation of the system should be prioritized in order to early identify new waves of Covid-19 but also any future novel respiratory pathogen. In order to empower the SS, it would be advisable to increase the population coverage about 2% which is the actual standard.

Time course of the upper limb motor recovery in subacute stroke patients undergoing conventional or robotic rehabilitation. A preliminary report

Upper limb recovery is a complex process and a strong challenge in the rehabilitation of patients after stroke. Several studies have been conducted to compare the efficacy of conventional and robotic rehabilitation to restore the upper limb motor impairment following a stroke. However, the evolution of the upper limb motor ability during an intervention, as well as the time point when the patient stops improving (the so call plateau), are rarely measured, and never compared between the two approaches. These latter aspects are very important considering the need for an optimization of the economic resources. In this study, the time course of the upper limb motor recovery of 24 subacute stroke patients undergoing a 30-session robotic or conventional treatment was analyzed through the upper extremity portion of the Fugl-Meyer Assessment scale (FMA-UE). The FMA-UE was administered before the treatment, and after 10, 20, and 30 rehabilitation sessions. Statistical analysis showed that, according to the FMA-UE, the time course in the two groups was similar: patients did not change between the baseline and the 10-session assessment, while they improved between 10 and 20 sessions, and between 20 and 30 sessions, with most of the gain observed between 10 and 20 sessions. This result suggests that 30-session robotic or conventional rehabilitation programs induce a similar curve trend in the upper limb motor recovery of patients with subacute stroke, with an important increase in the middle of the program and without reaching a clear plateau in the analyzed time interval.

Primary papillary epithelial tumour of the sella: expanding the spectrum of TTF-1-positive sellar lesions

AIM

To describe four novel primary epithelial tumours of the sella with papillary architecture and Thyroid Transcription Factor 1 (TTF-1) expression.

METHODS

Paraffin-embedded tissue from the four cases and recurrence of patient 1 was investigated with haematoxylin-eosin, special histochemical stains, immunohistochemistry with a broad panel of antibodies and next-generation sequencing. The ultrastructure of one tumour was studied in tissue retrieved from paraffin.

RESULTS

The lesions occurred in three females aged 20, 26 and 42 years and a male aged 49 years. They presented with signs and symptoms secondary to pituitary stalk compression. Preoperative neuroimaging documented mixed solid and cystic, enhancing sellar masses with suprasellar extension. Histologically, the tumours showed thin papillae lined by a single layer of cytokeratin and TTF-1-positive cuboidal and cylindrical cells with mildly atypical nucleus. Next-generation sequencing performed in three cases did not identify any mutations. The main differential diagnosis included metastasis from lung or thyroid carcinoma, extraventricular choroid plexus papilloma and sellar ependymoma.

CONCLUSION

We suggest the descriptive term of primary papillary epithelial tumour of the sella (PPETS) for this entity and propose that it could represent the intracranial equivalent of thyroid-like low-grade nasopharyngeal papillary adenocarcinoma. The cell of origin of PPETS remains undetermined although the intense and ubiquitous expression of TTF-1 may suggest a derivation from the infundibulum or ventricular recess. Our study expands the spectrum of sellar TTF-1-positive tumour and challenges the view that they all derive from pituicytes.

The Response of Osteoblasts and Bone to Sinusoidal Electromagnetic Fields: Insights from the Literature

Electromagnetic fields (EMFs) have been proposed as a tool to ameliorate bone formation and healing. Despite their promising results, however, they have failed to enter routine clinical protocols to treat bone conditions where higher bone mass has to be achieved. This is no doubt also due to a fundamental lack of knowledge and understanding on their effects and the optimal settings for attaining the desired therapeutic effects. This review analysed the available in vitro and in vivo studies that assessed the effects of sinusoidal EMFs (SEMFs) on bone and bone cells, comparing the results and investigating possible mechanisms of action by which SEMFs interact with tissues and cells. The effects of SEMFs on bone have not been as thoroughly investigated as pulsed EMFs; however, abundant evidence shows that SEMFs affect the proliferation and differentiation of osteoblastic cells, acting on multiple cellular mechanisms. SEMFs have also proven to increase bone mass in rodents under normal conditions and in osteoporotic animals.

Titanium Dioxide Nanowires Grown on Titanium Disks Create a Nanostructured Surface with Improved In Vitro Osteogenic Potential

Current biomedical research is centered on the study of nanomaterials and their effects in biological environments. In particular, there is an increasing interest on TiO₂ nanostructures for biomedical applications such as drug delivery or implant materials. In this framework, we present a Chemical Vapour Deposition process to synthesize titanium dioxide nanowires (NWs) on a commercially pure titanium substrate and we test the material In Vitro as a culture substrate for murine osteoblast-like MC3T3-E1 cells. A physical-morphological, structural and optical-characterization of the inorganic samples is performed by Electron Microscopy techniques and X-ray Diffraction, showing that a mat of crystalline rutile TiO₂ NWs is obtained over the commercial substrate. In Vitro biological tests are performed by seeding MC3T3-E1 cells on the material and studying cell morphology, the cellmaterial interface and the osteoblast gene expression. These experiments show good cell adhesion to the nano-structured surface and a higher degree of early osteoblastic differentiation compared to control titanium surfaces, indicating that the present nano-structured material has good osteogenic potential for biomedical applications.

Cellular xenotransplantation of animal cells into people: benefits and risk

The main benefit of xenotransplantation is its potential to overcome the worldwide organ shortage experienced in allotransplantation. Allogeneic transplantation is the only successful therapy for several life-threatening diseases, with cell, tissue or organ donation only partially meeting the demand and many patients dying while waiting for treatment. With supply falling short of demand, it is foreseen that the use of porcine material may at some stage overcome the existing gap between organ availability and clinical need. Recently, pig islet cells have been utilised in clinical trials, with safety being demonstrated. Indeed, pig-derived cells present several advantages: i) porcine cells have a stable function and differentiation pattern and are not tumorigenic; ii) pig cells have been shown to meet the physiological needs in large animal models; iii) the source of pig cells can be scaled up to meet demands in a highly standardised manner, and with respect to animal welfare regulations; iv) 'designated-pathogen-free' (DPF) pig lines can be produced, which could result in a higher safety profile than allotransplantation itself; v) the risk of zoonosis, which was raised years ago as the major hurdle, has been recently circumvented and is actually viewed as a controlled risk; and vi) immune risks are being circumvented via the use of genetically modified donor animals and encapsulation of porcine cells, particularly for the treatment of diabetes. Overall, the benefit appears to outweigh potential risks with respect to cellular xenotransplantation and this is discussed further in this review.

SURF1 knockout cloned pigs: Early onset of a severe lethal phenotype

Leigh syndrome (LS) associated with cytochrome c oxidase (COX) deficiency is an early onset, fatal mitochondrial encephalopathy, leading to multiple neurological failure and eventually death, usually in the first decade of life. Mutations in SURF1, a nuclear gene encoding a mitochondrial protein involved in COX assembly, are among the most common causes of LS. LSSURF1 patients display severe, isolated COX deficiency in all tissues, including cultured fibroblasts and skeletal muscle. Recombinant, constitutive SURF1-/- mice show diffuse COX deficiency, but fail to recapitulate the severity of the human clinical phenotype. Pigs are an attractive alternative model for human diseases, because of their size, as well as metabolic, physiological and genetic similarity to humans. Here, we determined the complete sequence of the swine SURF1 gene, disrupted it in pig primary fibroblast cell lines using both TALENs and CRISPR/Cas9 genome editing systems, before finally generating SURF1-/- and SURF1-/+ pigs by Somatic Cell Nuclear Transfer (SCNT). SURF1-/- pigs were characterized by failure to thrive, muscle weakness and highly reduced life span with elevated perinatal mortality, compared to heterozygous SURF1-/+ and wild type littermates. Surprisingly, no obvious COX deficiency was detected in SURF1-/- tissues, although histochemical analysis revealed the presence of COX deficiency in jejunum villi and total mRNA sequencing (RNAseq) showed that several COX subunit-encoding genes were significantly down-regulated in SURF1-/- skeletal muscles. In addition, neuropathological findings, indicated a delay in central nervous system development of newborn SURF1-/- piglets. Our results suggest a broader role of sSURF1 in mitochondrial bioenergetics.

A Case of Malignant Phyllodes Tumor with Muscular and Fatty Differentiations

A 50-year-old female underwent surgical removal of a mammary phyllodes tumor, whose peculiar histologic feature was the coexistence of areas of liposarcoma and leiomyosarcoma. The morphologic differential diagnosis is briefly discussed.

Suramin in Combination with 5-Fluorouracil (5-FU) and Leucovorin (LV) in Metastatic Colorectal Cancer Patients Resistant to 5-FU+LV-Based Chemotherapy

AIMS AND BACKGROUND

Suramin has been shown to be of interest as a potential new anticancer agent because of its capacity to inhibit the binding of several growth factors to their receptors and to inhibit the growth of cancer cells in vitro. Since multi-autocrine loops involving growth factors which are antagonized by suramin have been demonstrated in colorectal cancer, we previously evaluated the activity of suramin in patients with advanced colorectal cancer. Interestingly, in this study three patients who had received 5-FU+LV after suramin, although heavily pretreated with fluoropyrimidines, obtained an objective response. This observation was intriguing as it might have been that suramin had changed the biology of the tumor, making it sensitive to 5-FU+LV. We therefore conducted the present study to investigate the possibility that suramin might overcome the resistance to 5-FU+LV.

METHODS AND STUDY DESIGN

Only colorectal cancer patients with metastatic and progressive disease during 5-FU+LV-based chemotherapy were eligible for this study. Suramin was administered for eight weeks at doses determined by means of a computer-assisted dosing algorithm that used Bayesian pharmacokinetics to maintain suramin plasma concentrations of 200-250 microg/ml. 5-FU was administered weekly at a dosis of 450 mg/m2 halfway through a two-hour infusion of I-LV 250 mg/m2 starting one week after the initiation of suramin for a maximum of 26 weeks.

RESULTS

Treatment was relatively well tolerated, but no objective responses were observed after the accrual of 13 patients in the first stage of the trial. Consequently, the trial was interrupted according to the initial two-stage sampling design.

CONCLUSIONS

The present study does not support the hypothesis that suramin might overcome resistance to 5-FU+LV and its use in colorectal cancer is not recommended.

Interobserver Reproducibility of Immunohistochemical Her-2/Neu Assessment in Human Breast Cancer: An Update from INQAT round III

The clinical interest in HER-2/neu is related to trastuzumab, a drug used to treat patients with invasive breast carcinoma overexpressing the HER-2/neu protein. It is very important to correctly identify those patients who may benefit from trastuzumab by accurate assessment of the HER-2/neu status. Of the various methods available, the Dako Herceptest for immunohistochemical assay is considered the most reliable to reach this goal. The aim of this study was to investigate within a group of Italian laboratories the reproducibility of the results of HER-2/neu assessment by means of the Dako scoring system on slides stained with the Herceptest kit. This study was also conceived as the continuation of one of our previous studies, which was similar in its aims but different in the classification criteria adopted. Our results show that, whereas the intra-observer reproducibility was generally satisfactory, the interobserver reproducibility was not. Moreover, our findings confirm that the two extreme classes (0 and 3+) are more easy to identify than the other two and that the Herceptest does not allow to discriminate optimally between scoring classes 2+ and 3+. These findings are relevant in clinical practice where the treatment choice is based on categories defined by this assay, suggesting the need of adopting educational programs and/or new reference materials to improve the assay performance.

112 Identification of Solute Carrier Family 5 Member 9 (SLC5A9) as Biomarker of In Vivo and In Vitro Oocyte Developmental Competence

The transcriptome associated with the ability of oocytes to support embryogenesis and development remains unclear. The aim of this study was to compare the mRNA expression pattern between oocytes collected from fertile heifers (H) and repeat breeders (RB) using RNAseq. Oocytes were collected by ovum pick-up from Italian Simmental (IS) and Holstein Friesian (HF) heifers that became pregnant at the following oestrus, and from cows of the same breeds classified as RB after they failed to become pregnant for a minimum of 3 consecutive AI. Oocytes from each animal (5 for HF_RB, 3 each for all other groups) were pooled and sequenced using Illumina HiSEqn 2000 (Illumina Inc., San Diego, CA, USA). Principal component analysis showed that HF oocytes clustered away from those of IS, irrespective of the fertility status. However, within breeds, H and RB always clustered apart from each other. This suggests that differences in the transcriptional blueprint between breeds was more prominent than differences related to fertility. However, these were still strong when considering breeds separately, therefore we treated breeds as independent groups and performed differential expression analysis on H v. RB in IS and HF. DESEqn 2 identified 135 differentially expressed genes when we compared H and RB in IS and 2124 in HF. This difference in number of DE genes between the 2 breeds reflects the fact that the variance between H and RB transcriptional patterns in HF is larger than in IS. We looked for genes that were differentially and consistently expressed between H and RB in both breeds and identified 10 genes: histone H2B, exo/endonuclease G, solute carrier family 5 member 9, BH3 interacting domain death agonist, TBK1 binding protein 1, purine-rich element binding protein A, tRNA-yW synthesising protein 1 homologue, Jun oncogene, FRA10AC1 homologue, and SKI oncogene. To validate their potential use as biomarkers, we performed a preliminary in vitro validation by RT-qPCR. As described in the literature, oocytes collected from ovaries with more than 10 follicles of 2 to 6 mm were classified as high quality, while those collected from ovaries with fewer than 10 follicles were classified as low quality (Gandolfi et al. 1997 Theriogenology 48, 1153-1160). Gene expression analysis confirmed SLC5A9, a membrane-bound protein involved in sodium-dependent transport of glucose, as a potential biomarker to discriminate between a competent and incompetent oocyte. Altogether, our data provide a detailed overview of the mRNA pattern defining the differences between a competent and incompetent oocyte in vivo, and identified a new potential marker able to differentiate fertile and infertile oocyte both in vivo and in vitro. Study supported by PRIN 08–09, EU-Quantomics no. 222664 and Carraresi Foundation.

35 Interspecies Somatic Cell Nuclear Transfer Embryos that Form Nucleoli do not Always Activate Mitochondrial Functional Differentiation at the Time of Embryonic Genome Activation

Embryonic genome activation (EGA) is a complex process that needs a good orchestration of all biochemical processes at the time of maternal-to-embryonic transition. Mitochondria are strictly dependent on the nucleus for their correct activity as ~1500 mitochondrial genes have nuclear localisation. The finding of transcriptional activation and accumulation of mRNAs related to mitochondrial biogenesis (Mtango et al. 2008 Reprod. Fertil. Dev. 20, 846-859) around the time of EGA confirmed the role of nucleus in this process. Studying mitochondria behaviour in interspecies somatic cell nuclear transfer (iSCNT) embryos (Lagutina et al. 2010 Reproduction 140, 273-285), we have found that at the time of EGA, mitochondria activation could be demonstrated by JC-1 accumulation. We suggested that comparison of the mean green fluorescence intensity (FI) that corresponds to the fluorescence of the monomeric form of the dye and correlates to relative mitochondrial mass (Mancini et al. 1997) in iSCNT and control nuclear transfer (NT) could serve as a test to assess EGA in iSCNT embryos. The aim of this study was to estimate nuclear-cytoplasmic interaction in iSCNT embryos that formed nucleoli at the time of EGA (Lagutina et al. 2011 Reproduction 141, 453-465) such as embryos derived from bovine oocytes and bovine (control), buffalo or ovine donor nuclei, and from porcine oocytes and porcine (control), horse, or rabbit nuclei. Embryos 72 h after activation were stained with 2 μM JC-1 in SOF-HEPES with 10% FCS at 37°C for 1 h. Images were collected using a fluorescein isothiocyanate (FITC) filter and analysed with Adobe Photoshop Elements 2 (Adobe Systems, San Jose, CA, USA). The data are presented as mean FI of the embryo. To demonstrate the effect of EGA inhibition on mitochondria, bovine and porcine NT embryos were cultured in medium supplemented with 25 μg/mL α-amanitin (AA) from 48 to 72 h after activation. The analyses of mean FI of the embryos showed that ovine and buffalo nuclei were able to support mitochondrial mass accumulation in iSCNT embryos with bovine oocytes equal to control bovine NT embryos (35 ± 11.2; 41.9 ± 14.8; 36.2 ± 7.6, respectively) that was significantly higher than in bovine embryos treated with AA (15.4 ± 4.9; P < 0.05). In the iSCNT embryos composed of porcine oocytes and equine or rabbit nuclei, mean FI values (20 ± 13.4; 18.3 ± 5.5, respectively) were comparable with those in porcine NT embryos treated with AA (16.2 ± 6.2), and were significantly lower than in porcine control (91 ± 47.7; P < 0.05) NT embryos, demonstrating the inability of equine and rabbit nuclei to properly govern the porcine mitochondria mass growth at the time of EGA. In conclusion, nucleolus formation and activation of nuclear encoded mitochondrial genes at the time of EGA cannot serve, per se, as a marker of correct embryonic genome activation in iSCNT embryos, because, in our conditions, no iSCNT embryos developed to blastocyst (Lagutina et al. 2010 Reproduction 140, 273-285). This knowledge about behaviour of different embryo compartments at the time of EGA could extend our understanding of the whole process. This work was funded by Translink (EU FP7 no. 603049) and Xenoislet projects (EU FP7 no. 601827).

171 Protective Effect of Sodium Pyruvate Against H2O2-Induced Oxidative Stress in Bovine and Swine Oocytes

A previous study from our laboratory (Ramos-Ibeas et al. 2017 Mol. Cell. Biochem. 429, 137-150, 10.1007/s11010-017-2942-z) described the protective effect of sodium pyruvate (SP) against H2O2-induced oxidative stress in somatic and embryonic stem cells. In this study, we tested the same experimental conditions on bovine and swine oocytes during in vitro maturation (IVM). To this aim, cumulus-enclosed oocytes (COC) recovered from bovine and swine ovaries were treated for 1 h with different concentrations of H2O2 and then matured in serum-free TCM-199 with and without SP supplementation. All experiments were done in 3 replicates using 12 to 20 oocytes per experimental group; data were analysed by two-way ANOVA. As a first step, we determined the dose-response curve of H2O2 treatment during IVM, using the reaching of metaphase 2 as endpoint. We found that swine COC were more sensitive to H2O2 damage than bovine COC: indeed, they tolerated a range of concentrations from 128 to 512 μM, whereas the range for bovine COC was between 1024 and 4096 μM. The COC from both species were treated for 1 h with 128 μM (swine) or 2048 μM (bovine) H2O2 and then matured with or without different concentrations of SP. Control COC, unexposed to H2O2, were also matured with and without SP supplementation. We found that the addition of 25 mM SP to swine COC reduced the maturation rate both in control and H2O2-treated groups. Instead, reducing the addition of SP to 10 mM we observed a beneficial effect because the metaphase II level in treated oocytes increased from 38% (15/40) to 67% (24/36) and the difference was statistically significant. In bovine COC, the addition of 25 mM SP did not affect control oocytes during IVM but decreased maturation rate in treated oocytes, whereas 10 mM SP had no effect on the control group and showed a tendency to increase maturation rate in treated oocytes. In a second set of experiments, to determine if cumulus cells acted as a barrier for SP to reach the oocyte, the COC were denuded after H2O2 treatment and matured with or without SP. In swine denuded oocytes (DO) matured with SP, the rate of metaphase II increased significantly both in control [from 71% (34/48) to 92% (44/48)] and in treated groups [from 48% (23/48) to 72% (36/50)]. In bovine DO, the supplementation of SP did not increase the maturation rate significantly (25/41 v. 29/41 in control groups, 12/36 v. 18/40 in treated groups). In conclusion, we found that toxic H2O2 concentrations were approximately 10-fold higher for bovine than for swine, indicating that bovine COC were more resistant to oxidative stress. This could explain why SP supplementation had a significant protective effect in swine but only a minor effect in bovine. Moreover, the difference in SP effect between bovine and swine COC could be due to their morphology because bovine cumulus is often larger and more compact than swine cumulus and this difference could influence how SP reaches the inner oocyte and how it is metabolized. This work was funded by projects EpiHealth FP7 n. 278418, EpiHealthNet FP7-PEOPLE-2012-ITN n. 317146 and Fecund FP7 n. 312097.

Anti-fibronectin aptamers improve the colonization of chitosan films modified with D-(+) Raffinose by murine osteoblastic cells

The aim of the present study was to investigate how the enrichment of chitosan films with anti-fibronectin aptamers could enhance scaffold colonization by osteoblasts, by improving their adhesion and accelerating their proliferation. Chitosan discs were enriched with excess of anti-fibronectin aptamer. Aptamer adsorption on chitosan was monitored by measuring aptamer concentration in the supernatant by spectrophotometry, as well as its release, while functionalization was confirmed by labelling aptamers with a DNA intercalating dye. Chitosan samples were then characterized morphologically with atomic force microscopy and physically with contact angle measurement. Chitosan enrichment with fibronectin was then investigated by immunofluorescence and Bradford assay. 2% chitosan discs were then enriched with increasing doses of aptamers and used as culture substrates for MC3T3-E1 cells. Cell growth was monitored by optical microscopy, while cell viability and metabolic activity were assessed by chemiluminescence and by Resazurin Sodium Salt assay. Cell morphology was investigated by cytofluorescence and by scanning electron microscopy. Chitosan films efficiently bound and retained aptamers. Aptamers did not affect the amount of adsorbed fibronectin, but affected osteoblasts behavior. Cell growth was proportional to the amount of aptamer used for the functionalization, as well as aptamers influenced cell morphology and their adhesion to the substrate. Our results demonstrate that the enrichment of chitosan films with aptamers could selectively improve osteoblasts behavior. Furthermore, our results support further investigation of this type of functionalization as a suitable modification to ameliorate the biocompatibility of biomaterial for hard tissue engineering applications.

Stanozolol-soaked grafts enhance new bone formation in rat calvarial critical-size defects

Androgen hormones play a significant role in regulating bone morphogenesis and in maintaining bone homeostasis throughout life. This study aimed to investigate the local effects of the non-aromatizable androgen stanozolol (ST) on bone regeneration in rats. Bilateral critical-size defects were created in the parietal bone of 26 male Wistar rats: the defect on one side was filled with a deproteinized bovine bone scaffold (DBB) soaked in ST solution (test) and the contralateral with DBB alone (control). Samples were collected at one month and three months. Histomorphometry revealed a significantly higher new bone formation (NB) (24.41% ± 4.14% versus 15.01% ± 2.43%, p < 0.05) and mineral apposition rate (MAR) (9.20 μm/day ± 0.37 versus 6.50 μm/day ± 1.09, p < 0.05) in the test versus control group at one month. Accordingly, real time-polymerase chain reaction revealed a consistently higher Runx2 expression in test samples (fold change test/control: 4.50 ± 1.17, p ≤ 0.05). No morphometrical differences between groups were detected at three months (p > 0.05). However, test samples were characterized by an increase in blood capillary density from one month (11.43 n mm^-2 ± 2.01) to three months (28.26 n mm^-2 ± 5.62), providing evidence of a vital remodeling tissue. Control samples presented a decrease of anti-Osterix (SP7)/anti-osteocalcin (BGLAP) (3.9 n mm^-2 ± 0.32 versus 1.01 n mm^-2 ± 0.20) and alkaline phosphatase (ALP) (12.14 n mm^-2 ± 6.29 versus 6.29 n mm^-2 ± 2.73) immunohistochemical-positive elements, which was suggestive of a stabilized healing phase. Based on these observations, local ST administration boosted bone regeneration in rat calvarial critical-size defects at one month. This study showed the potential of local steroid delivery in bone regeneration.

Study of GSK3b inhibitors SB415286 and SB216763 to improve osteoblastic differentiation on microstructured titanium

Rough titanium surfaces enhance cell response to activation of Wnt canonical signalling, a pathway required for osteoblast differentiation. The present study investigated the effects of GSK3β-inhibitors SB216763 and SB415286 on osteoblastic differentiation on titanium surfaces with different topography and wettability. Osteoblastic MC3T3 cells were plated on smooth (Pickled), sand-blasted/acid-etched (SLA) or hyper hydrophilic SLA (modSLA) titanium discs and transfected with a reporter vector sys-tem for Wnt canonical signalling. Cells were also seeded in the presence or in the absence of GSK3b-inhibitors SB216763 or SB415286 and their viability, morphology and the expression of Wnt target and osteoblast specific genes was assessed by Real Time PCR. Inhibitors altered cell morphology and mostly reduced cell viability at high concentration. SB415286 markedly increased the expression of ALP in MC3T3 cells on rough surfaces at the concentration of 100 nM before decreasing its expression at higher concentrations. OCN expression was unaffected. Increasing concentrations of SB216763 increased the expression of ALP in MC3T3 cells on rough surfaces but OCN expression was not changed at any con-centration. SB216763 and SB415286 inhibitors should be further investigated as potential tools to improve cell differentiation on titanium surfaces for endosseous implants.

126 EXPRESSION OF THE RECEPTOR FOR ADVANCED GLYCATION END PRODUCTS IN BOVINE OOCYTES AND EMBRYOS CULTURED IN LOW AND HIGH OXYGEN

The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily that binds a broad repertoire of advanced glycation end products ligands. It is constitutively expressed at a high level during embryonic development, but its levels decrease in adult tissues. The RAGE-ligand interaction induces a series of signal transduction cascades and leads to the activation of several inflammatory signalling pathways. This is why RAGE is frequently associated with pro-inflammatory responses and it is implicated as an underlying condition in immune disorders, cardiovascular diseases, diabetes, Alzheimer’s disease, and cancer. However, the physiological function of RAGE during embryogenesis and in aging is largely undefined. The aim of this work was to determine the basal levels on RAGE expression in bovine oocytes (germinal vesicle, GV, and in vitro-matured metaphase II) and in vitro-derived embryos developed in SOF medium, by qPCR (3 replicates each containing pooled RNA from 20 oocytes or embryos, t-test P < 0.05) and immunostaining. The expression of RAGE was similar in bovine oocytes, in cleaving embryos up to morula, and afterward declined at the blastocyst stage. However, a more detailed investigation, by the separation of the inner cell mass (ICM) from the trophoblast, indicated that expression decreased only in the trophoblast (over 5-fold) while it was maintained high in the isolated ICM. In the trophoblast, compared to the ICM, this finding coincided with an elevated expression of PSMA6 gene, which encodes for the 20S proteasome subunit, and ubiquitin (UBB) gene, suggesting a link between proteasome activity and RAGE expression. Then we investigated the expression of RAGE and the proteasome-ubiquitin system in embryos cultured under different oxygen concentrations [i.e. physiological (5%) or high (20%) O2 levels]. Preliminary results showed that RAGE expression was lower in embryos cultured in 20% O2 and conversely the expression of PSMA6 and UBB genes was higher. Thus, these results indicate that the activity of RAGE-mediated stress response pathway in pre-implantation bovine embryos is affected by O2 tension during in vitro culture. This work was funded by projects Epihealth FP7 n. 278418, EpiHealthNet FP7-PEOPLE-2012-ITN n. 317146, and Fecund FP7 n. 312097.

203 SINGLE-STEP GENE EDITING OF 3 XENOANTIGENS IN PORCINE FIBROBLASTS USING PROGRAMMABLE NUCLEASES

Programmable nucleases (ZFN, Tal Effector Nucleases, and CRISPR) opened a new era for mammal genome editing, in particular for the pigs used for xenotransplantation. Multiple gene editing events are required both for knockout (KO) of xenoantigens and for targeted integration of human protective genes (Perota et al. 2016 J. Genet. Genomics 43, 233–23). The objective of the present work was to edit selected pig lines to KO the enzymes coding for the most relevant xenoantigens (i.e. GGTA1, CMAH, and B4GalNT2), combining Talens and CRISPR/Cas9 technologies to magnetic beads selection (Li et al. 2013 Xenotransplantation 22, 20–31). Primary porcine adult fibroblasts were transfected using Nucleofector (V-024 program). In a single reaction 2 × 106 fibroblasts were co-transfected using 2 different sets of TALENS (4 μg/set) specific for CMAH (Conchon et al., 2013) and GGTA1 (Perota et al., 2015) genes together with B4GalNT2-specific CRISPR/Cas9 expression vector (2 μg; pX330-B4GalNT2; Estrada et al., 2015). Eight days post-transfection (DPT), Gal–/– cells were selected initially using biotin-conjugated IB4 lectin (Sigma, St. Louis, MO, USA) and magnetic beads (Dynabeads M-280, Thermo Fisher Scientific, Waltham, MA, USA). The selected cells were then plated on 150-mm Petri dishes (200 cells/dish) and cultured for 10 days. Selected colonies were expanded for PCR analysis and cryopreserved for somatic cell nuclear transfer (SCNT). All colonies were analysed by PCR for CMAH gene and their resulting products were digested with HindIII (HindIII-RFLP). Colonies that lost wild-type HindIII as a consequence of Talens effected deletion were PCR characterised for GGTA1, selecting those that had detectable Indels after gel electrophoresis and finally analysed by PCR for B4GalNT2. All PCR products were validated by sequencing for all the 3 genes of interest (TopoTA, Thermo Fisher Scientific). Selected colonies were used as nuclear donors for SCNT (Lagutina et al., 2006). Eight DPT we obtained 3.45 ×106 cells. About 6.0 × 103 Gal-negative cells (0.17%) were collected from the supernatant after magnetic beads separation. Eighteen DPT, 120 colonies were picked up and their HindIII-RFLP analyses on CMAH gene revealed that 22 colonies (18.3%) were KO for both CMAH alleles. Of these 22 colonies following electrophoretic analyses of GGTA1-PCR products, 13 colonies had detectable Indels. These 13 colonies were finally PCR analysed and sequenced for B4GalNT2 and sequenced. Final sequencing results confirmed that 2 colonies (1.6%) resulted in KO for the 3 genes. Three different zona-free SCNT experiments were done and 579 reconstructed embryos were obtained. On Day 7, 322 morulae or blastocysts (56%) were transferred in 3 synchronised sows and 2 (66%) became pregnant. In conclusion, after gene editing with programmable nucleases, combining beads-mediated selection with well-designed molecular analyses, we developed a multistep assay that can be used efficiently to detect desired gene edited events in cell colonies suitable for the SCNT. Embryos generated after SCNT were able to establish pregnancies at a high rate. This work is supported by European FP7 grants Translink (n° 603049) and Xenoislet (n° 601827).

Blood fatty acid composition in relation to allergy in children aged 2-9 years: results from the European IDEFICS study

BACKGROUND/OBJECTIVES

Blood polyunsaturated fatty acids (PUFA) are involved in allergy development, but the etiological role of n-6 and n-3 PUFA is still controversial. A European multicenter study of children (IDEFICS) provided the opportunity to explore the cross-sectional association between fatty acids (FA) and allergy.

SUBJECTS/METHODS

Blood FA levels were measured in 2600 children aged 2-9 years and were recorded as the percentage of weight of all FA detected. Logistic regression of allergy status on FA components was adjusted for age, sex, country, body mass index, family history of allergic disease, breast-feeding, and number of siblings. The results were given as odds ratios (OR) for current vs no allergy ever and an increase in FA by 1 s.d.

RESULTS

Overall, higher proportions of n-6 PUFA were associated with higher odds of allergy (OR=1.21 (1.05, 1.40)). Monounsaturated FA (MUFA) were associated with reduced risk for allergy (OR=0.75 (0.65, 0.87)), whereas saturated FA did not differ by allergy status. The strongest associations were observed in children <4 years old, with ORs of allergy given as 1.62 (1.15, 2.29) for n-3 PUFA and 0.63 (0.42, 0.95) for MUFA. With regard to individual FA, these associations were independently observed for docosapentaenoic acid (22:5 n-3) and oleic acid (18:1 n-9).

CONCLUSIONS

Both PUFA subtypes were positively associated with allergy in an age-dependent manner, whereas MUFA was associated with less allergy. The observation of high proportions of n-3 PUFA in allergic children younger than 4 years might help to understand the nature of early onset of atopic disease.

Improved scaffold biocompatibility through anti-Fibronectin aptamer functionalization

Protein adsorption is the first and decisive step to define cell-biomaterial interaction. Guiding the adsorption of desired protein species may represent a viable approach to promote cell activities conducive to tissue regeneration. The aim of the present study was to investigate whether immobilized anti-Fibronectin aptamers could promote the attachment and growth of osteoblastic cells. Polyethyleneglycole diacrylate/thiolated Hyaluronic Acid hydrogels (PEGDA/tHA) were coated with anti-Fibronectin aptamers. Hydrogel loading and Fibronectin bonding were investigated, through spectrophotometry and Bradford assay. Subsequently, human osteoblasts (hOBs) were cultured on hydrogels for 10days in 2D and 3D cultures. Cells were monitored through microscopy and stained for focal adhesions, microfilaments and nuclei using fluorescence microscopy. Samples were also included in paraffin and stained with Hematoxylin-Eosin. Cell number on hydrogels was quantitated over time. Cell migration into the hydrogels was also studied through Calcein AM staining. Aptamers increased the number of adherent hOBs and their cytoplasm appeared more spread and richer in adhesion complexes than on control hydrogels. Viability assays confirmed that significantly more cells were present on hydrogels in the presence of aptamers, already after 48h of culture. When hOBs were encapsulated into hydrogels, cells were more numerous on aptamer-containing PEGDA-tHA. Cells migrated deeper in the gel in the presence of DNA aptamers, appearing on different focus planes. Our data demonstrate that anti-Fibronectin aptamers promote scaffold enrichment for this protein, thus improving cell adhesion and scaffold colonization.

STATEMENT OF SIGNIFICANCE

We believe aptamer coating of biomaterials is a useful and viable approach to improve the performance of scaffold materials for both research and possibly clinical purposes, because different medical devices could be envisaged able to capture bioactive mediators from the patients' blood and concentrate them where they are needed, on the biomaterial itself. At the same time, this technology could be used to confer 3D cell culture scaffold with the ability to store proteins, such as Fibronectin, taking it from the medium and capture what is produced by cells. This is an improvement of traditional biomaterials that can be enriched with exogenous molecules but are not able to selectively capture a desired molecule.

Hepatitis C virus outbreak in a haemodialysis unit: learning from failures

The investigation of an outbreak of hepatitis C virus in an Italian haemodialysis (HD) centre showed that three patients acquired infection with the same strain, affecting a chronically hepatitis C virus (HCV)-infected patient receiving HD in the same room and during the same shifts. Through our observational analysis many possible modes of transmission were identified, but none could be definitively identified as the route of HCV spread in this small cluster. This outbreak confirms that repeated opportunities for nosocomial HCV transmission may occur among HD patients due to several breaches in the standard precautions for bloodborne infections by healthcare staff.

The response of osteoblastic MC3T3-E1 cells to micro- and nano-textured, hydrophilic and bioactive titanium surfaces

The aim of the present work was to investigate the morphology and activity of the murine osteoblastic cell line MC3T3 on control smooth (Machined), commercially available rough (ZT) titanium discs, and on titanium samples obtained by modifying the ZT treatment protocol, and herein labelled as ZTF, ZTM and ZTFM. Cells were evaluated at SEM and immunofluorescence for morphology and cell-to-cell interactions and by MTT assay and real time PCR for cell growth and function. Microscopy showed that ZT modified protocols could differently affect cell shape and distribution. All the tested surfaces showed good biocompatibility by viability assay. However, cells on smoother surfaces appeared to express higher levels of transcript for Collagen 1a1, the main component of extracellular matrix, by real time PCR. Expression of the early differentiation marker Alkaline Phosphatase was higher on ZTF surfaces and ZTM enhanced the expression of later osteoblastic markers Osteoprotegerin and Osteocalcin. Noteworthy, the expression of Connexin 43, a component of cell-to-cell contacts and hemichannels, followed a similar pattern to differentiation marker genes and was higher in cells on ZTM surfaces, consistently with the microscopic observation of cell clusters. Taken together, this data showed that ZTF and ZTM treatment protocols appeared to improve the basal sand-blasting/acid-etching ZT procedure with ZTM surfaces promoting the most mature stage of differentiation.

205 HOLDING PIG OOCYTES AT 24°C PRIOR TO IN VITRO MATURATION ALTERS THE DEVELOPMENTAL CAPACITY AFTER IN VITRO FERTILISATION BUT NOT PARTHENOGENETIC ACTIVATION

The in vitro production of porcine embryos is of great interest because of the increasing importance of the swine as an animal model and a tissue donor for biomedical or biotechnological applications. Availability of ovaries at selected time of the day can be a limitation; therefore, the possibility to maintain immature oocytes for some hours can be very useful. The aim of this study is to determine whether holding recovered oocytes at 24°C for 24 h alters the maturation process and/or the developmental capacity. Immature sow oocytes were either matured in vitro for 42 h at 38.5°C (control group; CTR) or kept in 2 mL of HEPES-SOF in the dark at 24°C for 24 h before maturation (experimental group; +24 h). After maturation, cumulus cells were removed, and the number at metaphase II were recorded. For parthenogenetic activation (PGA), oocytes with a visible polar body were activated at 48 h of maturation as previously described (Lagutina et al. 2006). For IVF experiments frozen-thawed boar semen was prepared through a discontinuous density gradient, washed in TALP Ca2+-free, diluted in TALP : SOF = 1 : 1 supplemented with 6 mg mL–1 of fatty acid-free BSA, hypotaurine and epinephrine, mixed with oocytes after partial removal of the cumulus cells, at 43 h of maturation and cultured in 5% CO2 in humidified air at 38.5°C. After 24 h of IVF, oocytes were denuded and cultured in mSOF-1 in atmosphere of 5% O2 and 5% CO2. The same culture conditions were used after parthenogenetic activation. Half of the medium was changed with mSOF-1 at Day 3 and with mSOF-2 at Day 5. The cleavage and the cumulative Day 7 blastocyst (BLD7) rates and cell number of IVF BLD6 were recorded. For each group, blastocysts on Day 6 were fixed and cell number counted, whereas the other embryos were left in culture until Day 7 (cumulative D7 = BLD6 fixed + BLD7). All experiments were done in 3 replicates. The data were compared by Student’s t-test and chi-square test. Maturation rates as recorded for the presence of the polar body did not differ (CTR: 255/312, 82%; +24 h: 208/256, 81%). There was no significant difference (P < 0.05, chi-squared test) between CTR and +24 h group cleavage (144/165: 87% and 127/138: 92%, respectively) and BLD7 rate (47/165: 28% and 34/138: 25%, respectively) in the PGA. Whereas no difference (P < 0.05, chi-squared test) was observed between CTR and +24 h group cleavage (111/180: 62% and 99/186: 53%, respectively) in the IVF, but the BLD7 rate in +24 h group was significantly lower (48/180: 27% in the CTR group, 27/186: 15% in the +24 h group). However, the cell number of IVF BLD6 was not altered by holding at 24°C (n = 22: 25 ± 10 cells in the CTR, n = 8: 22 ± 13 cells in the +24 h) (P < 0.05, 2-tailed Student t-test). These experiments show that holding at 24°C for 24 h before maturation can alter the developmental capacity of IVF-produced embryos but not that of parthenogenetically activated ones. More replicates are needed to study the kinetics of maturation and to confirm our results. MitCare project (ERC n 322424) is acknowledged for support of this project.

Re-designing the substrate binding pocket of laccase for enhanced oxidation of sinapic acid

Iterative saturation mutagenesis was performed over six residues delimiting the substrate binding pocket of a high redox potential chimeric laccase with the aim of enhancing its activity over sinapic acid, a lignin-related phenol of industrial interest.

191 SEARCHING FOR THE IN VIVO TRANSCRIPTOME BLUEPRINT OF COMPETENT BOVINE OOCYTES

Gene expression in early stage embryos relies mostly on post-transcriptional control of maternal transcripts accumulated during oocyte maturation. However, while the building process to obtain a competent oocyte is now better understood, it is still not clear what transcriptome blueprint composes a competent oocyte. The aim of the study was to compare the mRNA expression pattern between oocytes collected from fertile heifers and repeat breeders by using RNAseq. Oocytes were collected by ovum pickup from 3 heifers that were 11–15 months of age and became pregnant at the following oestrus and from 4 adult cows with an age of 4 to 7 years, classified as repeat breeders after they failed to become pregnant for a minimum of 3 consecutive AI. To obtain oocytes from follicles with the same degree of development, at time 0 all follicles visible through transrectal ultrasound examination were removed by transvaginal aspiration. Five days later oocytes were collected by ovum pick up from the newly formed follicles with diameters >5 mm. Oocytes from each animal were pooled and sequenced as a single sample. Total RNA was extracted by RNeasy Micro Kit (Qiagen, Valencia, CA, USA). Amplified cDNA, was prepared starting from total RNA using the Ovation RNA-Seq System V2 (Nugen Technologies, San Carlos, CA, USA). After library preparation with TruSeq DNA Sample Prep kit (Illumina, Madison, WI, USA), sequencing was performed on an Illumina HiSEqn 2000. Galaxy and Chipster open web-based platforms were used to analyse the data. We identified 49 differentially expressed genes. Heifers’ oocytes mRNA pattern indicated greater potential to sustain cell division. In particular, oocytes expressed more Keratin 14 (a gene involved in cell proliferation) and kinesin family member 20B (a protein involved in cytokinesis). More competent oocytes also have a greater ability to repair single-strand breaks due to the high levels of endo/exonuclease (5′-3′), endonuclease G-like. This may reflect greater capacity to neutralise DNA damage and, therefore, greater ability to preserve and transmit high-quality DNA. Repeat breeders portray a different landscape; their greater expression of Jun oncogene, Heat shock protein 1, Stimulated by retinoic acid gene6, arylhydrocarbon receptor nuclear translocator, fibromodulin, and aryl-hydrocarbon receptor repressor suggest that these oocytes have been subjected to environmental stress during oocyte maturation. Their greater expressions of inhibin α, stearoyl-CoA desaturase, junctional adhesion molecule 2 have been previously shown to correlate with a reduced oocyte developmental potential. Furthermore, the Cannabinoid receptor protein 1 expression suggests a compromised ion function that can lead to a failed activation of the development program. Finally, the greater expression of Ubiquilin3 and Heat shock protein 1 led to high protein and mRNA degradation, respectively, suggesting that these oocytes are deprived of essential components to sustain embryo growth. In conclusion our data provide the first detailed snapshot of the mRNA pattern defining the differences between a competent oocyte and an incompetent oocyte in vivo. Study supported by PRIN 2008, 2009 and EU-Quantomics.

Reference values of whole-blood fatty acids by age and sex from European children aged 3-8 years

OBJECTIVES

To establish reference values for fatty acids (FA) especially for n-3 and n-6 long-chain polyunsaturated FAs (LC PUFA) in whole-blood samples from apparently healthy 3-8-year-old European children. The whole-blood FA composition was analysed and the age- and sex-specific distribution of FA was determined.

DESIGN AND SUBJECTS

Blood samples for FA analysis were taken from 2661 children of the IDEFICS (identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study cohort. Children with obesity (n=454) and other diseases that are known to alter the FA composition (n=450) were excluded leaving 1653 participants in the reference population.

MEASUREMENTS

The FA composition of whole blood was analysed from blood drops by a rapid, validated gas chromatographic method.

RESULTS

Pearson correlation coefficients showed an age-dependent increase of C18:2n-6 and a decrease of C18:1n-9 in a subsample of normal weight boys and girls. Other significant correlations with age were weak and only seen either in boys or in girls, whereas most of the FA did not show any age dependence. For age-dependent n-3 and n-6 PUFA as well as for other FA that are correlated with age (16:0, C18:0 and C18:1n-9) percentiles analysed with the general additive model for location scale and shape are presented. A higher median in boys than in girls was observed for C20:3n-6, C20:4n-6 and C22:4n-6.

CONCLUSIONS

Given the reported associations between FA status and health-related outcome, the provision of FA reference ranges may be useful for the interpretation of the FA status of children in epidemiological and clinical studies.

Isolation and in vitro characterization of bovine amniotic fluid derived stem cells at different trimesters of pregnancy

Amniotic fluid (AF) is a source of multipotent mesenchymal stem cells (MSCs), very promising cells for tissue engineering in clinical application. The aim of this work was to isolate and characterize cells isolated from bovine AF as alternative sources of primitive multipotent stem cells in a species that could be a large-animal model for biomedical and biotechnology researches. Samples were recovered, at slaughterhouse, from 39 pregnant cows at different trimesters of pregnancy and cells were cultured in vitro. At passages (P) 3 and 7 differentiation towards chondrogenic, osteogenic and adipogenic lineages was induced. Flow cytometry analysis for CD90, CD105, CD73, CD44, CD34, CD45 and CD14 was performed, immunocytochemistry (ICC) for Oct4, SSEA4, α-SMA, Vimentin, N- and E- Cadherin and CK and qPCR analysis for OCT4, NANOG and SOX2 were carried out. The cell yield was significantly higher in the first trimester compared to the second and the third one (P < 0.05). Cells were isolated from 25/39 samples and cell population appeared heterogeneous. Two main cell types were identified in samples from all trimesters: round- (RS) and spindle-shaped (SS) cells. 17/25 samples showed both populations (mixed, MX). Both cell types showed MSC-markers and differentiation capability with some variability related to the passages. The SS-population also expressed low levels of stemness markers such as NANOG and SSEA4 but not OCT4. Bovine AF shows a heterogeneous cell population containing also MSCs, multipotent cells that represent an intermediate stage between embryonic stem cells and adult ones.

Bortezomib, C1-inhibitor and plasma exchange do not prolong the survival of multi-transgenic GalT-KO pig kidney xenografts in baboons

Galactosyl-transferase KO (GalT-KO) pigs represent a potential solution to xenograft rejection, particularly in the context of additional genetic modifications. We have performed life supporting kidney xenotransplantation into baboons utilizing GalT-KO pigs transgenic for human CD55/CD59/CD39/HT. Baboons received tacrolimus, mycophenolate mofetil, corticosteroids and recombinant human C1 inhibitor combined with cyclophosphamide or bortezomib with or without 2-3 plasma exchanges. One baboon received a control GalT-KO xenograft with the latter immunosuppression. All immunosuppressed baboons rejected the xenografts between days 9 and 15 with signs of acute humoral rejection, in contrast to untreated controls (n = 2) that lost their grafts on days 3 and 4. Immunofluorescence analyses showed deposition of IgM, C3, C5b-9 in rejected grafts, without C4d staining, indicating classical complement pathway blockade but alternate pathway activation. Moreover, rejected organs exhibited predominantly monocyte/macrophage infiltration with minimal lymphocyte representation. None of the recipients showed any signs of porcine endogenous retrovirus transmission but some showed evidence of porcine cytomegalovirus (PCMV) replication within the xenografts. Our work indicates that the addition of bortezomib and plasma exchange to the immunosuppressive regimen did not significantly prolong the survival of multi-transgenic GalT-KO renal xenografts. Non-Gal antibodies, the alternative complement pathway, innate mechanisms with monocyte activation and PCMV replication may have contributed to rejection.