Development of a biologically immortalized equine stem cell line.

Bone repair in horses implies invasive surgeries and increased cost. Research on musculoskeletal disorders therapy in horses includes cell-based therapy with mesenchymal stromal cells (MSCs). Mesenchymal stromal cells can be obtained from bone marrow (BMMSCs). Unfortunately, BMMSCs have limited cell replication in vitro. The objective of this study was to develop a biologically immortalized equine stem cell line derived from bone marrow, with unlimited in-vitro proliferation and the ability to differentiate into bone cells. Equine BMMSCs were transfected and immortalized with human telomerase reverse transcriptase (hTERT) gene. Cell passages from equine immortal BMMSCs were characterized by the presence of stemness CD markers and expression of multi-potent differentiation genes (OCT-4, SOX2, and NANOG). Equine immortal BMMSCs were incubated in osteogenic medium and bone cell differentiation was determined by alkaline phosphatase and von Kossa staining, and osteogenic gene expression (osteocalcin, Runx2, and osterix). Telomerase activity was determined by telomeric repeat amplification technique. Results showed that equine immortal BMMSCs were able to replicate in-vitro up to passage 50 and maintain stem cell characteristics by the presence of CD90 and expression of multi-potent genes. Equine immortal BMMSCs were able to differentiate into bone cells, which was confirmed by the positive osteogenic staining and gene expression. Equine BMMSCs were successfully immortalized and maintained characteristics of stem cells and readily differentiated into osteogenic cells. Extending the life span of equine BMMSCs by transfection of the hTERT gene will revolutionize the clinical use of MSCs by making them available to orthopedic surgeons "off the shelf."

La réparation osseuse chez les chevaux implique des chirurgies invasives et des coûts accrus. La recherche sur la thérapie des troubles musculosquelettiques chez les chevaux comprend la thérapie cellulaire avec des cellules stromales mésenchymateuses (CSM). Les CSM peuvent être obtenues à partir de la moelle osseuse (BMMSC). Malheureusement, les BMMSC ont une réplication cellulaire limitée in vitro. L'objectif de cette étude était de développer une lignée de cellules souches équines immortalisées biologiquement dérivées de la moelle osseuse, avec une prolifération in vitro illimitée et la capacité de se différencier en cellules osseuses. Les BMMSC équines ont été transfectées et immortalisées avec le gène de la transcriptase inverse de la télomérase humaine (hTERT). Les passages cellulaires des BMMSC immortels équins ont été caractérisés par la présence de marqueurs CD de souche et l'expression de gènes de différenciation multipotents (OCT-4, SOX2 et NANOG). Des BMMSC équins immortels ont été incubés dans un milieu ostéogénique et la différenciation des cellules osseuses a été déterminée par coloration à la phosphatase alcaline et de von Kossa, et l'expression des gènes ostéogéniques (ostéocalcine, Runx2 et osterix). L'activité de la télomérase a été déterminée par la technique d'amplification répétée des télomères. Les résultats ont montré que les BMMSC équins immortels étaient capables de se répliquer in vitro jusqu'au passage 50 et de maintenir les caractéristiques des cellules souches par la présence de CD90 et l'expression de gènes multipotents. Les BMMSC immortelles équines ont pu se différencier en cellules osseuses, ce qui a été confirmé par la coloration ostéogénique positive et l'expression des gènes. Les BMMSC équines ont été immortalisées avec succès et ont conservé les caractéristiques des cellules souches et facilement différenciées en cellules ostéogéniques. L'extension de la durée de vie des BMMSC équins par transfection du gène hTERT révolutionnera l'utilisation clinique des MSC en les mettant à la disposition des chirurgiens orthopédistes prête à l'emploi.(Traduit par Docteur Serge Messier).

Detection of endotoxin in plasma of hospitalized diarrheic calves.

OBJECTIVES: To investigate whether lipopolysaccharide (LPS) is present in plasma of calves with naturally occurring diarrhea. The second objective was to determine whether plasma [LPS] correlates with clinical, hematological, biochemical, and acid-base variables, and whether [LPS] differs between surviving and nonsurviving diarrheic calves. DESIGN: Prospective observational study (January 2012-May 2014). SETTING: Veterinary teaching hospital. ANIMALS: Thirty-four calves <28 days old admitted for diagnosis and treatment of diarrhea and 30 healthy control calves. MEASUREMENTS AND MAIN RESULTS: Admission demographics, physical examination, blood gas, biochemistry analysis, and outcome data were recorded. Plasma concentration of LPS was determined using a bovine LPS ELISA assay. Plasma [LPS] was detected in both healthy and diarrheic calves. Plasma [LPS] was significantly higher in diarrheic than healthy calves (median: 0.99 ng/mL; Interquartile range (IQR): 0.068, vs 0.88 ng/mL; 0.065 ng/mL, respectively; P < 0.001). Plasma [LPS] was higher in nonsurviving (1.04 ng/mL; 0.07 ng/mL) than in surviving calves (0.98 ng/mL; 0.022 ng/mL; P < 0.001). Plasma [LPS] was higher in beef (1.07 ng/mL; 0.182 ng/mL) than in dairy diarrheic calves (0.99 ng/mL; 0.022 ng/mL; P < 0.001). In diarrheic calves, plasma [LPS] correlated with [l-lactate] (r2 = 0.496; P = 0.002); hypoglycemia (r2 = -0.453; P = 0.007); increased unmeasured strong ions (r2 = 0.332; P = 0.050), [Mg2+ ] (r2 = 0.475; P = 0.004), and [phosphate] (r2 = 0.468; P = 0.005), and increased aspartate aminotransferase activity (r2 = 0.348; P = 0.003). CONCLUSIONS: This study highlights a potential role of LPS in the pathogenesis of metabolic derangements such as hyperlactatemia, hypoglycemia, and increased concentration of unmeasured strong anions in diarrheic calves. Further investigation evaluating the effect of LPS on l-lactate and glucose metabolism in diarrheic calves is warranted.

A Method for Functional Task Alignment Analysis of an Arthrocentesis Simulator.

INTRODUCTION: During simulation-based education, simulators are subjected to procedures composed of a variety of tasks and processes. Simulators should functionally represent a patient in response to the physical action of these tasks. The aim of this work was to describe a method for determining whether a simulator does or does not have sufficient functional task alignment (FTA) to be used in a simulation. METHODS: Potential performance checklist items were gathered from published arthrocentesis guidelines and aggregated into a performance checklist using Lawshe's method. An expert panel used this performance checklist and an FTA analysis questionnaire to evaluate a simulator's ability to respond to the physical actions required by the performance checklist. RESULTS: Thirteen items, from a pool of 39, were included on the performance checklist. Experts had mixed reviews of the simulator's FTA and its suitability for use in simulation. Unexpectedly, some positive FTA was found for several tasks where the simulator lacked functionality. CONCLUSIONS: By developing a detailed list of specific tasks required to complete a clinical procedure, and surveying experts on the simulator's response to those actions, educators can gain insight into the simulator's clinical accuracy and suitability. Unexpected of positive FTA ratings of function deficits suggest that further revision of the survey method is required.

IKKß inhibition prevents fat-induced beta cell dysfunction in vitro and in vivo in rodents.

AIMS/HYPOTHESIS: We have previously shown that oxidative stress plays a causal role in beta cell dysfunction induced by fat. Here, we address whether the proinflammatory kinase inhibitor of (nuclear factor) κB kinase ß (IKKß), which is activated by oxidative stress, is also implicated. METHODS: Fat (oleate or olive oil) was infused intravenously in Wistar rats for 48 h with or without the IKKß inhibitor salicylate. Thereafter, beta cell function was evaluated in vivo using hyperglycaemic clamps or ex vivo in islets isolated from fat-treated rats. We also exposed rat islets to oleate in culture, with or without salicylate and 4(2'-aminoethyl)amino-1,8-dimethylimidazo(1,2-a)quinoxaline; BMS-345541 (BMS, another inhibitor of IKKß) and evaluated beta cell function in vitro. Furthermore, oleate was infused in mice treated with BMS and in beta cell-specific Ikkb-null mice. RESULTS: 48 h infusion of fat impaired beta-cell function in vivo, assessed using the disposition index (DI), in rats (saline: 1.41 ± 0.13; oleate: 0.95 ± 0.11; olive oil [OLO]: 0.87 ± 0.15; p < 0.01 for both fats vs saline) and in mice (saline: 2.51 ± 0.39; oleate: 1.20 ± 0.19; p < 0.01 vs saline) and ex vivo (i.e., insulin secretion, units are pmol insulin islet-1 h-1) in rat islets (saline: 1.51 ± 0.13; oleate: 1.03 ± 0.10; OLO: 0.91 ± 0.13; p < 0.001 for both fats vs saline) and the dysfunction was prevented by co-infusion of salicylate in rats (oleate + salicylate: 1.30 ± 0.09; OLO + salicylate: 1.33 ± 0.23) or BMS in mice (oleate + BMS: 2.25 ± 0.42) in vivo and by salicylate in rat islets ex vivo (oleate + salicylate: 1.74 ± 0.31; OLO + salicylate: 1.54 ± 0.29). In cultured islets, 48 h exposure to oleate impaired beta-cell function ([in pmol insulin islet-1 h-1] control: 0.66 ± 0.12; oleate: 0.23 ± 0.03; p < 0.01 vs saline), an effect prevented by both inhibitors (oleate + salicylate: 0.98 ± 0.08; oleate + BMS: 0.50 ± 0.02). Genetic inhibition of IKKß also prevented fat-induced beta-cell dysfunction ex vivo ([in pmol insulin islet-1 h-1] control saline: 0.16 ± 0.02; control oleate: 0.10 ± 0.02; knockout oleate: 0.17 ± 0.04; p < 0.05 control saline vs. control oleate) and in vivo (DI: control saline: 3.86 ± 0.40; control oleate: 1.95 ± 0.29; knockout oleate: 2.96 ± 0.24; p < 0.01 control saline vs control oleate). CONCLUSIONS/INTERPRETATION: Our results demonstrate a causal role for IKKß in fat-induced beta cell dysfunction in vitro, ex vivo and in vivo.

Osteogenic potential of sorted equine mesenchymal stem cell subpopulations.

The objectives of this study were to use non-equilibrium gravitational field-flow fractionation (GrFFF), an immunotag-less method of sorting mesenchymal stem cells (MSCs), to sort equine muscle tissue-derived mesenchymal stem cells (MMSCs) and bone marrow-derived mesenchymal stem cells (BMSC) into subpopulations and to carry out assays in order to compare their osteogenic capabilities. Cells from 1 young adult horse were isolated from left semitendinosus muscle tissue and from bone marrow aspirates of the fourth and fifth sternebrae. Aliquots of 800 × 10(3) MSCs from each tissue source were sorted into 5 fractions using non-equilibrium GrFFF (GrFFF proprietary system). Pooled fractions were cultured and expanded for use in osteogenic assays, including flow cytometry, histochemistry, bone nodule assays, and real-time quantitative polymerase chain reaction (qPCR) for gene expression of osteocalcin (OCN), RUNX2, and osterix. Equine MMSCs and BMSCs were consistently sorted into 5 fractions that remained viable for use in further osteogenic assays. Statistical analysis confirmed strongly significant upregulation of OCN, RUNX2, and osterix for the BMSC fraction 4 with P < 0.00001. Flow cytometry revealed different cell size and granularity for BMSC fraction 4 and MMSC fraction 2 compared to unsorted controls and other fractions. Histochemisty and bone nodule assays revealed positive staining nodules without differences in average nodule area, perimeter, or stain intensity between tissues or fractions. As there are different subpopulations of MSCs with different osteogenic capacities within equine muscle- and bone marrow-derived sources, these differences must be taken into account when using equine stem cell therapy to induce bone healing in veterinary medicine.

Les objectifs de la présente étude étaient d'utiliser une méthode non-équilibrée de fractionnement par flot sous champs gravitationnel (GrFFF), une méthode sans marquage immunologique de séparation des cellules souches mésenchymateuses (MSCs), afin de séparer les cellules souches mésenchymateuses dérivées du tissu musculaire équin (MMSCs) et les cellules souches mésenchymateuses provenant de la moelle osseuse (BMSCs) en sous-populations et de réaliser des essais afin de comparer leurs capacités ostéogéniques. Des cellules provenant d'un jeune cheval adulte furent isolées du muscle semi-tendineux gauche et d'aspirations de la moelle osseuse de la quatrième et cinquième strernèbre. Des aliquotes de 800 × 103 MSCs provenant de chaque source de tissu furent séparés en 5 fractions par GrFFF non-équilibré (système breveté GrFFF). Des fractions regroupées ont été mises en culture afin de proliférer pour utilisation dans des essais ostéogéniques, incluant la cytométrie en flux, l'histochimie, des essais de nodules osseux, et l'amplification en chaine quantitative par la polymérase (qPCR) pour l'expression des gènes de l'ostéocalcine (OCN), RUNX2, et osterix. Les MMSCs et BMSCs équins étaient séparés de manière constante en 5 fractions qui demeuraient viables pour utilisation dans des essais ostéogéniques additionnels. Les analyses statistiques ont confirmé une régulation à la hausse très significative pour OCN, RUNX2 et osterix pour la fraction 4 des BMSC (P < 0,00001). La cytométrie en flux a révélé une taille et une granularité différente pour la fraction 4 des BMSCs et la fraction 2 des MMSCs comparativement aux témoins non-séparés et aux autres fractions. L'histochimie et les essais de nodules osseux ont révélé des nodules se colorant positivement sans différence pour les tissus ou les fractions dans la moyenne de la surface du nodule, du périmètre, ou de l'intensité de la coloration. Étant donné qu'il y a différentes sous-populations de MSCs avec différentes capacités ostéogéniques parmi les sources dérivées du muscle et de la moelle osseuse, ces différences doivent être prises en compte lors de l'utilisation thérapeutique en médecine vétérinaire des cellules souches pour induire la guérison osseuse.(Traduit par Docteur Serge Messier).

Application of a novel sorting system for equine mesenchymal stem cells (MSCs).

The objective of this study was to validate non-equilibrium gravitational field-flow fractionation (GrFFF), an immunotag-less method of sorting mesenchymal stem cells (MSCs) into subpopulations, for use with MSCs derived from equine muscle tissue, periosteal tissue, bone marrow, and adipose tissue. Cells were collected from 6 young, adult horses, postmortem. Cells were isolated from left semitendinosus muscle tissue, periosteal tissue from the distomedial aspect of the right tibia, bone marrow aspirates from the fourth and fifth sternebrae, and left supragluteal subcutaneous adipose tissue. Aliquots of 800 × 10(3) MSCs from each tissue source were separated and injected into a ribbon-like capillary device by continuous flow (GrFFF proprietary system). Cells were sorted into 6 fractions and absorbencies [optical density (OD)] were read. Six fractions from each of the 6 aliquots were then combined to provide pooled fractions that had adequate cell numbers to seed at equal concentrations into assays. Equine muscle tissue-derived, periosteal tissue-derived, bone marrow-derived, and adipose tissue-derived mesenchymal stem cells were consistently sorted into 6 fractions that remained viable for use in further assays. Fraction 1 had more cuboidal morphology in culture when compared to the other fractions. Statistical analysis of the fraction absorbencies (OD) revealed a P-value of < 0.05 when fractions 2 and 3 were compared to fractions 1, 4, 5, and 6. It was concluded that non-equilibrium GrFFF is a valid method for sorting equine muscle tissue-derived, periosteal tissue-derived, bone marrow-derived, and adipose tissue-derived mesenchymal stem cells into subpopulations that remain viable, thus securing its potential for use in equine stem cell applications and veterinary medicine.

L'objectif de la présente étude était de valider une méthode non-équilibrée de fractionnement par flot sous champs gravitationnel (GrFFF), une méthode sans marquage immunologique de séparation des cellules souches mésenchymateuses (MSCs) en sous-populations, pour utilisations avec des MSCs provenant de tissu musculaire, de tissu de périoste, de moelle osseuse, et de tissu adipeux de chevaux. Les cellules furent prélevées post-mortem à partir de six jeunes chevaux adultes. Les cellules furent isolées du muscle semi-tendineux gauche, du périoste de l'aspect disto-médial du tibia droit, d'aspirations de moelle osseuse de la quatrième et cinquième sternèbres, et du tissu adipeux sous-cutané de la région supra-glutéale gauche. Des aliquots de 800 × 103 MSCs de chaque tissu ont été séparés et injectés dans un appareil capillaire apparenté à un ruban par flot continu (système breveté GrFFF). Les cellules furent séparées en six fractions et les absorbances [densité optique (OD)] notées. Six fractions de chacun des six aliquots furent par la suite combinées afin de fournir des fractions poolées qui avaient des nombres adéquats de cellules pour ensemencer des concentrations égales dans les essais. Les MSCs provenant du tissu musculaire, du périoste, de la moelle osseuse, et du tissu adipeux étaient de manière constante séparées en six fractions qui sont demeurées viables pour utilisation dans des essais ultérieurs. La fraction 1 avait plus de cellules de morphologie cuboïde comparativement aux autres fractions. Les analyses statistiques des OD des fractions ont révélé une valeur de P < 0,05 lorsque les fractions 2 et 3 étaient comparées aux fractions 1, 4, 5, et 6. Il fut conclu que la méthode GrFFF non-équilibrée est une méthode valide pour séparer les MSCs équines dérivées des cellules musculaires, du périoste, de la moelle osseuse, et du tissu adipeux en sous-populations qui demeurent viables, assurant ainsi son potentiel pour utilisation en médecine vétérinaire et les applications avec les cellules souches équines.(Traduit par Docteur Serge Messier).

Evaluation of an in vivo heterotopic model of osteogenic differentiation of equine bone marrow and muscle mesenchymal stem cells in fibrin glue scaffold.

Autologous mesenchymal stem cells (MSCs) have been used as a potential cell-based therapy in various animal and human diseases. Their differentiation capacity makes them useful as a novel strategy in the treatment of tissue injury in which the healing process is compromised or delayed. In horses, bone healing is slow, taking a minimum of 6-12 months. The osteogenic capacity of equine bone marrow and muscle MSCs mixed with fibrin glue or phosphate-buffered saline (PBS) as a scaffold is assessed. Bone production by the following groups was compared: Group 1, bone marrow (BM) MSCs in fibrin glue; Group 2, muscle (M) MSCs in fibrin glue; Group 3, BM MSCs in PBS; Group 4, M MSCs in PBS and as a control; Group 5, fibrin glue without cells. BM and M MSCs underwent osteogenic stimulation for 48 h prior to being injected intramuscularly into nude mice. After 4 weeks, the mice were killed and muscle samples were collected and evaluated for bone formation and mineralization by using radiology, histochemistry and immunohistochemistry. Positive bone formation and mineralization were confirmed in Group 1 in nude mice based on calcium deposition and the presence of osteocalcin and collagen type I; in addition, a radiopaque area was observed on radiographs. However, no evidence of mineralization or bone formation was observed in Groups 2-5. In this animal model, equine BM MSCs mixed with fibrin glue showed better osteogenic differentiation capacity compared with BM MSCs in PBS and M MSCs in either carrier.

Characterization and osteogenic potential of equine muscle tissue- and periosteal tissue-derived mesenchymal stem cells in comparison with bone marrow- and adipose tissue-derived mesenchymal stem cells.

OBJECTIVE: To characterize equine muscle tissue- and periosteal tissue-derived cells as mesenchymal stem cells (MSCs) and assess their proliferation capacity and osteogenic potential in comparison with bone marrow- and adipose tissue-derived MSCs. SAMPLE: Tissues from 10 equine cadavers. PROCEDURES: Cells were isolated from left semitendinosus muscle tissue, periosteal tissue from the distomedial aspect of the right tibia, bone marrow aspirates from the fourth and fifth sternebrae, and adipose tissue from the left subcutaneous region. Mesenchymal stem cells were characterized on the basis of morphology, adherence to plastic, trilineage differentiation, and detection of stem cell surface markers via immunofluorescence and flow cytometry. Mesenchymal stem cells were tested for osteogenic potential with osteocalcin gene expression via real-time PCR assay. Mesenchymal stem cell cultures were counted at 24, 48, 72, and 96 hours to determine tissue-specific MSC proliferative capacity. RESULTS: Equine muscle tissue- and periosteal tissue-derived cells were characterized as MSCs on the basis of spindle-shaped morphology, adherence to plastic, trilineage differentiation, presence of CD44 and CD90 cell surface markers, and nearly complete absence of CD45 and CD34 cell surface markers. Muscle tissue-, periosteal tissue-, and adipose tissue-derived MSCs proliferated significantly faster than did bone marrow-derived MSCs at 72 and 96 hours. CONCLUSIONS AND CLINICAL RELEVANCE: Equine muscle and periosteum are sources of MSCs. Equine muscle- and periosteal-derived MSCs have osteogenic potential comparable to that of equine adipose- and bone marrow-derived MSCs, which could make them useful for tissue engineering applications in equine medicine.

Scaffold effects on osteogenic differentiation of equine mesenchymal stem cells: an in vitro comparative study.

The in vitro viability, osteogenic differentiation, and mineralization of four different equine mesenchymal stem cells (MSCs) from bone marrow, periosteum, muscle, and adipose tissue are compared, when they are cultured with different collagen-based scaffolds or with fibrin glue. The results indicate that bone marrow cells are the best source of MSCs for osteogenic differentiation, and that an electrochemically aggregated collagen gives the highest cell viability and best osteogenic differentiation among the four kinds of scaffolds studied.

Isolation, characterization, and in vitro proliferation of canine mesenchymal stem cells derived from bone marrow, adipose tissue, muscle, and periosteum.

OBJECTIVE: To isolate and characterize mesenchymal stem cells (MSCs) from canine muscle and periosteum and compare proliferative capacities of bone marrow-, adipose tissue-, muscle-, and periosteum-derived MSCs (BMSCs, AMSCs, MMSCs, and PMSCs, respectively). SAMPLE: -7 canine cadavers. PROCEDURES: -MSCs were characterized on the basis of morphology, immunofluorescence of MSC-associated cell surface markers, and expression of pluripotency-associated transcription factors. Morphological and histochemical methods were used to evaluate differentiation of MSCs cultured in adipogenic, osteogenic, and chondrogenic media. Messenger ribonucleic acid expression of alkaline phosphatase, RUNX2, OSTERIX, and OSTEOPONTIN were evaluated as markers for osteogenic differentiation. Passage-1 MSCs were counted at 24, 48, 72, and 96 hours to determine tissue-specific MSC proliferative capacity. Mesenchymal stem cell yield per gram of tissue was calculated for confluent passage-1 MSCs. RESULTS: -Successful isolation of BMSCs, AMSCs, MMSCs, and PMSCs was determined on the basis of morphology; expression of CD44 and CD90; no expression of CD34 and CD45; mRNA expression of SOX2, OCT4, and NANOG; and adipogenic and osteogenic differentiation. Proliferative capacity was not significantly different among BMSCs, AMSCs, MMSCs, and PMSCs over a 4-day culture period. Periosteum provided a significantly higher MSC yield per gram of tissue once confluent in passage 1 (mean ± SD of 19,400,000 ± 12,800,000 of PMSCs/g of periosteum obtained in a mean ± SD of 13 ± 1.64 days). CONCLUSIONS AND CLINICAL RELEVANCE: -Results indicated that canine muscle and periosteum may be sources of MSCs. Periosteum was a superior tissue source for MSC yield and may be useful in allogenic applications.

Uncoupling protein-2 increases nitric oxide production and TNFAIP3 pathway activation in pancreatic islets.

Mutations in the uncoupling protein 2 (Ucp2) gene are linked to type-2 diabetes. Here, a potential mechanism by which lack of UCP2 is cytoprotective in pancreatic ß-cells was investigated. Nitric oxide (NO) production was elevated in Ucp2(-/-) islets. Proliferation (cyclin D2, Ccnd2) and anti-apoptosis (Tnfaip3) genes had increased expression in Ucp2(-/-) islets, whereas the mRNA of pro-apoptosis genes (Jun, Myc) was reduced. TNFAIP3 cellular localization was detected in both α- and ß-cells of Ucp2(-/-) islets but in neither α- nor ß-cells of UCP2(+)(/)(+) islets, where it was detected in pancreatic polypeptide-expressing cells. TNFAIP3 distribution was not markedly altered 14 days after streptozotocin treatment. Basal apoptosis was attenuated in Ucp2(-/-) ß-cells, while the nuclear factor κB (NF-κB) pathway was transactivated after islet isolation. Ucp2(+/+) and Ucp2(-/-) islets were treated with cytokines for 24 h. Cytokines did not increase NF-κB transactivation or apoptosis in Ucp2(-/-) islets and TNFAIP3 was more strongly induced in Ucp2(-/-) islets. Inhibition of NO production strongly reduced NF-κB activation and apoptosis. These data show that null expression of Ucp2 induces transactivation of NF-κB in isolated islets, possibly due to NO-dependent up-regulation of inhibitor of κB kinase ß activity. NF-κB transactivation appears to result in altered expression of genes that enhance a pro-survival phenotype basally and when ß-cells are exposed to cytokines. TNFAIP3 is of particular interest because of its ability to regulate NF-κB signaling pathways.

Infectious bursal disease virus (IBDV) induces apoptosis in chicken B cells.

The ability of infectious bursal disease virus (IBDV) serotypes 1 and 2, and the role of VP4 of both serotypes as well as the capacity of three IBDV intermediate serotype 1-specific vaccine strains to induce apoptosis in a chicken B-lymphocyte cell line, DT40, were investigated using the TUNEL technique. It was observed that IBDV serotype 1 infected the DT40 cell line and directly induced apoptosis. In contrast, the non-pathogenic serotype 2 neither infected nor induced apoptosis, but was able to reduce the serotype 1-induced apoptosis when the two viruses were present in combination. VP4 of both serotypes did not induce apoptosis. IBDV VP2 of serotype 2 induced apoptosis in the same proportion and intensity as VP2 of serotype 1. IBDV intermediate vaccines varied in their ability to induce apoptosis in the DT40 cell line, which was also decreased-delayed in presence of serotype 2 IBDV. We hypothesize that both serotypes compete for the same receptor in DT-40 cells, and suggest that IBDV-induced apoptosis is a multistep process involving virus replication, protein expression, and release of virions.

Zinc supplementation decreases hepatic copper accumulation in LEC rat: a model of Wilson's disease.

The effect of dietary zinc (Zn) supplementation on copper (Cu)-induced liver damage was investigated in Long-Evans Cinnamon rats (LEC), a model for Wilson's disease (WD). Four-week-old LEC (N=64) and control Long-Evans (LE) (N=32) female rats were divided into two groups; one group was fed with a Zn-supplemented diet (group I) and the other was given a normal rodent diet (group II). LEC rats were killed at 6, 8, 10, 12, 18, and 20 wk of age; the LE control rats were killed at 6, 12, 18, and 20 wk of age. Cu concentration in the liver was reduced in LEC rats fed the Zn-supplemented diet compared with LEC rats on the normal diet between 6 and 18 wk of age. Metallothionein (MT) concentration in the livers of LEC rats in group I increased between 12 and 20 wk of age, whereas hepatic MT concentration in LEC rats from group II decreased after 12 wk. Hepatocyte apoptosis, as determined by TUNEL, was reduced in Zn-supplemented LEC rats at all ages. Cholangiocellular carcinoma was observed only in LEC rats in group II at wk 20. These results suggest that Zn supplementation can reduce hepatic Cu concentration and delay the onset of clinical and pathological changes of Cu toxicity in LEC rats. Although the actual mechanism of protection is unknown, it could be explained by sequestration of dietary Cu by intestinal MT, induced by high dietary Zn content.

Identificación de Cryptosporidium en cerdos con enteritis / Identification of Cryptosporidium in pigs with enteritis in Mexico

Se observaron numerosos Cryptosporidium en el borde ciliado de las células epiteliales del intestino delgado, en tres lechones de 10 semanas de edad. Estos hallazgos se asociaron con una severa atrofia de vellosidades y moderada infiltración linfoide en la lámina propia. Además, en todos estos casos hubo una severa neumonía intersticial y linfoproliferativa compatible con una infección por Mycoplasma. Los estudios bacteriológicos fueron negativos a cepas enteropatógenas de Salmonella y Pasteurella. Estos cerdos pertenecían a una piara con mala higiene y sujetos a masivos tratamientos con varios antibióticos. Aunque el principal papel patológico de Cryptosporidium no puede ser atribuido en éste, la infección por este protozoario podría estar involucrada en el desarrollo de las lesiones. La cryptosporidiosis ha sido previamente notificada en becerros en México, pero este constituye el primer informe en cerdos

Peso húmedo del pulmón de conejos diabéticos sometidos a un desafío transtorácico con el lipopolisacárido de Klebsiella pneumoniae / lung wet weight of diabetic rabbits subjected to a transthoracic challenge with the Klebsiella pneumoniae lipopolysaccharide

El propósito de este estudio fue evaluar la respuesta inflamatoria del pulmón mediante histopatología y la determinación del peso húmedo pulmonar en conejos diabéticos sujetos a un desafío con lipopolisacárido (LPS) de Klebsiella pneumoniae. Fueron incluidos dos grupos. Ambos recibieron un desafío transtorácico con LPS directamente en los pulmones derechos. Los pulmones del lado izquierdo no inoculados se usaron como testigos. Los animales del grupo 1 recibieron el agente diabetogénico aloxana 110 días antes de la inoculación, mientras que los testigos (grupo 2) recibieron solución salina fisiológica. Cinco días después del desafío los conejos fueron sacrificados. El estudio histopatológico fue similar en ambos grupos; sin embargo, los pesos húmedos de los pulmones mostraron que los animales diabéticos tuvieron una disminución en la respuesta inflmatoria comparada con los testigos. Estos resultados concuerdan con los informes de deficiencias en la respuesta inflamatoria y mecanismos de reparación en diabéticos