Precision technologies for predictive diagnosis and study of the allometric growth of broiler chickens with breast myopathies

1. An experiment was carried out to validate techniques as predictive diagnostic tools for breast myopathies and to study the allometric growth of distinct parts of the body and meat quality of broilers.2. Infrared thermography was performed at 35 d of age. The surface temperatures of breasts of 300 birds were recorded, followed by ultrasound imaging.3. The birds were slaughtered and the cuts were made to weigh the body parts. Then, the breasts were evaluated as for the presence and severity of myopathies, from which nine treatments were established represented by the associated degrees of the myopathies white striping and wooden breast and breasts classified as normal.4. There was no difference in surface temperatures and echogenicity values between normal breasts and breasts affected by myopathies. At 35 d of age few fillets classified as normal were found.5. The breast showed late growth in relation to the body, regardless of characteristic lesions of myopathies. The most severe score of wooden breast affected meat quality variables.

Cerebral Malaria Model Applying Human Brain Organoids

Neural injuries in cerebral malaria patients are a significant cause of morbidity and mortality. Nevertheless, a comprehensive research approach to study this issue is lacking, so herein we propose an in vitro system to study human cerebral malaria using cellular approaches. Our first goal was to establish a cellular system to identify the molecular alterations in human brain vasculature cells that resemble the blood-brain barrier (BBB) in cerebral malaria (CM). Through transcriptomic analysis, we characterized specific gene expression profiles in human brain microvascular endothelial cells (HBMEC) activated by the Plasmodium falciparum parasites. We also suggest potential new genes related to parasitic activation. Then, we studied its impact at brain level after Plasmodium falciparum endothelial activation to gain a deeper understanding of the physiological mechanisms underlying CM. For that, the impact of HBMEC-P. falciparum-activated secretomes was evaluated in human brain organoids. Our results support the reliability of in vitro cellular models developed to mimic CM in several aspects. These systems can be of extreme importance to investigate the factors (parasitological and host) influencing CM, contributing to a molecular understanding of pathogenesis, brain injury, and dysfunction.

Phagocytotic activity and gene expression of leukocytes isolated from Astyanax lacustris

The constant intensification of aquaculture has considerable increased the stress levels of farmed fish and, consequently, the number and intensity of diseases outbreaks. Thus, studies on fish immune response, especially regarding the interaction of fish leukocytes with potential pathogens and xenobiotics are of great importance in order to develop new prophylactic and curative strategies. We isolated leukocytes from the head kidney of Astyanax lacustris-an important Neotropical fish species for aquaculture and a potential model for Neotropical aquaculture research-using a Percoll centrifugation protocol. The isolated leukocytes were incubated with lipopolysaccharide (LPS), and the expression of genes IL-1β, IL-8, LysC, and LysG were measured. We assessed the phagocytotic activity of leukocytes using Congo red-dyed yeast, a novel and cost-effective protocol that has been developed in this study. The isolated leukocytes responded to LPS induction, exhibiting strong IL-1β and IL-8 upregulation, two of the most important pro-inflammatory interleukins for vertebrates immune reponse. The optimal concentration of yeast for the phagocytic assay was 106 cells mL-1, resulting in acceptable phagocytic capacity (PC) but without excess of yeasts during the counting process, ensuring a high precision and accuracy of the method. To the best of our knowledge, the present study is the first to investigate the in vitro gene expression and phagocytic activity of leukocytes isolated from A. lacustris. Our findings will serve as a reference for future studies on the immunology and toxicology of Neotropical fish.

Energy requirements and efficiency of Alpine goats in early lactation

Dairy goats may rely heavily on body fat and protein reserves in early lactation. Therefore, we aimed to determine the energy requirement and estimate the efficiency of utilization the nutrients of tissues mobilized in the first 8 weeks of lactation for milk production using the comparative slaughter technique. The average initial body mass of 51 multiparous goats was 57.19 ± 8.38 kg and a body condition score of 3.0 ± 0.5. Three goats were slaughtered at the beginning of the experiment to serve as baseline animals to estimate initial empty BW and initial body composition. We used a complete randomized design in which the factor was the day of lactation for slaughtering (the 7th, 14th, 21st, 28th, 35th, 42nd, 49th and 56th day), with six repeats, totalling 48 goats. No fasting before slaughtering. All animals received a single experimental diet. The efficiency of transferring energy from body reserves to milk was estimated using a multiple linear regression equation yielding a value of 0.76. The total energy stored in the empty body decreased over the eight lactation weeks, from 726.47 ± 26.19 to 316.18 ± 49.21 MJ, a 56.47% reduction, mainly because of a reduction in the energy from internal fat of 3.96 ± 1.98 MJ/day. In conclusion, the net energy required for maintenance is 60 ± 30 kJ/BW^0.75 per day, and the net energy required for lactation decreases 70 ± 30 kJ/day during the first eight lactation weeks.

First Report of HLB Causal Agent in Psyllid in State of Bahia, Brazil

The state of Bahia ranks fourth in the national rank for citrus production, and the region of Chapada Diamantina is emerging an important producer of orange for fresh fruit market. Huanglongbing (HLB) is the major phytosanitary threat to Bahia citriculture. In Brazil, the disease was first reported in 2004 in São Paulo state. The bacterium Candidatus Liberibacter asiaticus (CLas) is one of the causal agents of HLB, which is transmitted by the insect vector Diaphorina citri Kuwayama (Hemiptera: Liviidae). Bahia is a HLB-free area; therefore, it is essential to monitor its citrus-producing areas to early detect any possible introduction of the CLas. This study aimed to monitor the presence of the bacteria in the insect vector. Diaphorina citri samples were collected from 2011 to 2014 in different cities located at Chapada Diamantina region and tested by qPCR for the presence of CLas. Three samples were considered positive to bacterium, and all from psyllids collected on Murraya paniculata in the city of Seabra.

The molecular landscape of osteogenesis imperfecta in a Brazilian tertiary service cohort

We have sought the molecular diagnosis of OI in 38 Brazilian cases through targeted sequencing of 15 candidate genes. While 71% had type 1 collagen-related OI, defects in FKBP10, PLOD2 and SERPINF1, and a potential digenic P3H1/WNT1 interaction were prominent causes of OI in this underrepresented population.

INTRODUCTION

Defects in type 1 collagen reportedly account for 85-90% of osteogenesis imperfecta (OI) cases, but most available molecular data has derived from Sanger sequencing-based approaches in developed countries. Massively parallel sequencing (MPS) allows for systematic and comprehensive analysis of OI genes simultaneously. Our objective was to obtain the molecular diagnosis of OI in a single Brazilian tertiary center cohort.

METHODS

Forty-nine individuals (84% adults) with a clinical diagnosis of OI, corresponding to 30 sporadic and 8 familial cases, were studied. Sixty-three percent had moderate to severe OI, and consanguinity was common (26%). Coding regions and 25-bp boundaries of 15 OI genes (COL1A1, COL1A2, IFITM5 [plus 5'UTR], SERPINF1, CRTAP, P3H1, PPIB, SERPINH1, FKBP10, PLOD2, BMP1, SP7, TMEM38B, WNT1, CREB3L1) were analyzed by targeted MPS and variants of interest were confirmed by Sanger sequencing or SNP array.

RESULTS

A molecular diagnosis was obtained in 97% of cases. COL1A1/COL1A2 variants were identified in 71%, whereas 26% had variants in other genes, predominantly FKBP10, PLOD2, and SERPINF1. A potential digenic interaction involving P3H1 and WNT1 was identified in one case. Phenotypic variability with collagen defects could not be explained by evident modifying variants. Four consanguineous cases were associated to heterozygous COL1A1/COL1A2 variants, and two nonconsanguineous cases had compound PLOD2 heterozygosity.

CONCLUSIONS

Novel disease-causing variants were identified in 29%, and a higher proportion of non-collagen defects was seen. Obtaining a precise diagnosis of OI in underrepresented populations allows expanding our understanding of its molecular landscape, potentially leading to improved personalized care in the future.

Application of Green Technology for the Acquisition of Extracts of Araçá (Psidium grandifolium Mart. ex DC.) Using Supercritical CO2 and Pressurized Ethanol: Characterization and Analysis of Activity

Brazil is home to a wide variety of flora, including several lesser known species, such as araçá that were processed in this study using two green technologies consecutively: supercritical fluid extraction (SFE) for nonpolar fraction and pressurized liquid extraction. For polar fraction, the experiments followed a central composite design involving ethanol as solvent, with temperature and static time in each bath as independent variables. Both extracts were analyzed for antioxidant and antimicrobial activities. Total phenolics content (TPC) was determined for all ethanol extracts. In the araçá essential oil (AEO) obtained by SFE, the extraction yield was 2.33%. The three major compounds of AEO were α-pinene (20.75%), p-cymene (20.50%), and o-cymene (20.05%). In ethanol extracts, the high yield (14.49%) was obtained at 74 °C/6 min and the major TPC (136.95 mg GAE/100 g) at 60 °C/9 min. Ethanol extracts presented good antioxidant activity (EC₅₀ = 6.37 mg/mL) at 74 °C/6 min. AEO was unable to reduce DPPH• concentration by 50%. Both extract types presented an inhibitory effect against Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus, while only the ethanol extracts presented effect against Listeria monocytogenes. This work had the aim to present the innovation of the use of a whole typical Brazilian fruit that gives rise to extracts with excellent properties for employment in both the pharmaceutical and food industries.

Performance and serum biochemical profile of Japanese quail supplemented with silymarin and contaminated with aflatoxin B1

The aim of this study was to evaluate the hepatoprotective effect of silymarin in diets contaminated or not with aflatoxin B1 (AFB1) on the productive performance and serum biochemical profile of Japanese quail (Coturnix coturnix japonica) in the laying phase. A total of 240 12-week-old Japanese quail was used in a completely randomized design in a 3 × 2 factorial scheme (additives x contaminated or not with AFB1 - 1,500 μg/kg), totaling 6 treatments and 5 replicates of 8 birds each. The additives used were silymarin (500 g/ton), adsorbent (1 kg/ton), and a control diet (without additive). Of the total aflatoxin content, 84.64% was AFB1; 4.28% was AFB2; 11.07% was AFG1; and AFG2 was not detected. The data were submitted to ANOVA, and means were compared by Tukey's test. There was no interaction (P > 0.05) between the additive and AFB1 on performance parameters. However, the inclusion of AF in diets reduced (P < 0.05) egg weight and feed intake, impairing feed conversion compared to the unchallenged groups. There was an increase (P < 0.05) in blood concentrations of aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), and creatine kinase (CK) in birds challenged with AFB1, regardless of the additive used, characterizing a possible alteration in hepatic metabolism. Serum total protein and globulin levels were reduced (P < 0.05) in birds challenged with toxins. The consumption of diets contaminated with 1,500 μg AFB1/kg altered hepatic function in quail, impairing productive performance and egg weight. The concentrations of silymarin and adsorbent evaluated in this study were not able to mitigate the negative effect of toxins on the metabolism and performance of laying quail.

Carryover of aflatoxins from feed to lambari fish (Astyanax altiparanae) tissues

The aim of this study was to verify the carryover of aflatoxin B₁ from feed to lambari fish. Aflatoxins (AF) were incorporated into feed, checking the levels by HPLC. Treatments were: Control, feed without toxin; A, feed + 10 µg AFB₁ kg^-1; B, feed + 20 µg AFB₁ kg^-1; and C, feed + 50 µg AFB₁ kg^-1. Juveniles of lambari fish were placed in 12 aquariums at a density of 50 fish/m². Fish were fed twice a day with extruded feed, at 5% of animal biomass. The unit sample was constituted by a pool of 10 fish. AFs B₁, B₂, G₁, G₂ and M₁ were quantified by HPLC in fish muscle and liver after 30, 60, 90 and 120 days of experiment. There was accumulation of AFs is fish liver and muscle, mainly after 90 days. Fish from treatment C had higher levels of AFB₁ in muscle when compared with the others, and AFB₁ in muscle at 120 days was similar to the levels in feed. Therefore, when lambari fish is exposed on a daily and long-term basis to AFs in feed, the regulation limits for AFs in animal feed do not guarantee safety for consumers.

Irradiated vacuum-packed lamb meat stored under refrigeration: microbiology, physicochemical stability and sensory acceptance

Reducing spoilage and indicator bacteria is important for microbiological stability in meat and meat products. The objective was to evaluate the effect of different doses of gamma radiation on the shelf-life of lamb meat, vacuum-packed and stored under refrigeration, by assessing the microbiological safety, physicochemical stability and sensory quality. Lamb loin cuts (Longissimus dorsi) were irradiated with 1.5kGy and 3.0kGy. The samples, including control, were stored at 1±1°C during 56days. Samples were analyzed on zero, 14, 28, 42 and 56days by their microbiological and physicochemical characteristics. Sensory quality was carried out on day zero. The results showed a reduction (p<0.05) in the microbial load of the irradiated samples. The acceptance of lamb loins was not affected (p>0.05) by the radiation doses. Thus gamma irradiation at 3.0kGy was effective in reducing the content of microorganisms, without harming the physicochemical characteristics evaluated.

Fumonisin B1 in cereal mixtures marketed in Brazil

The aim of this study was to detect and quantify fumonisin B1 (FB1) in cereal mixtures marketed in Brazil. Fifteen samples from different lots were acquired each month by internet from supermarkets during seven months, adding up to 105 analysed samples. The unit sample constituted of an original package with a minimum of 250 g. Extraction and clean-up of samples for FB1 determination were carried out using immunoaffinity columns. Identification and quantification of FB1 were performed by high performance liquid chromatography. Eighty-eight (83.8%) samples were contaminated with FB1 and four (3.8%) presented levels above 500 µg kg(-1) (634, 703, 1269 and 1876 µg kg(-1)). Maximum FB1 + FB2 levels allowed by Brazilian regulations will reach 1500 µg kg(-1) for corn flour in 2016 and 1000 µg kg(-1) for others corn products. This study showed that even at levels below the legislative limits, human exposure to this toxin can occur constantly.

Ochratoxin A in wines from 2002 to 2008 harvest marketed in Rio de Janeiro, Brazil

The occurrence of ochratoxin A (OTA) in wine from 2002 to 2008 harvest, traded in Rio de Janeiro State, was evaluated by analysing 43 national and 37 imported wines from Argentina (32) and Chile (5), adding up to 80 samples in total. OTA determination was performed using immunoaffinity columns and high-performance liquid chromatography. In 80 wine samples analysed, 25 (31.3%) were positive, presenting levels greater than 0.020 ng OTA mL⁻¹. It was not detected in imported wines. Within national wines, 58.1% of the samples were contaminated, with levels ranging from 0.020 to 0.050 ng mL⁻¹. The toxin was detected in 18 (69.2%) of 26 samples analysed of red table wine. Wines from 2008 harvest presented 84.6% of samples contaminated in 13 samples analysed. Despite the levels found in this study, they are below Brazilian tolerance limits. Nevertheless, the presence of OTA as found contributes to the human exposure to this toxin.

Energy resolution of gamma-ray spectroscopy of JET plasmas with a LaBr3 scintillator detector and digital data acquisition

A new high efficiency, high resolution, fast γ-ray spectrometer was recently installed at the JET tokamak. The spectrometer is based on a LaBr3(Ce) scintillator coupled to a photomultiplier tube. A digital data acquisition system is used to allow spectrometry with event rates in excess of 1 MHz expected in future JET DT plasmas. However, at the lower rates typical of present day experiments, digitization can degrade the energy resolution of the system, depending on the algorithms used for extracting pulse height information from the digitized pulses. In this paper, the digital and analog spectrometry methods were compared for different experimental conditions. An algorithm based on pulse shape fitting was developed, providing energy resolution equivalent to the traditional analog spectrometry method.

Gamma ray spectroscopy at high energy and high time resolution at JET

In fusion plasmas gamma ray emission is caused by reactions of fast particles, such as fusion alpha particles, with impurities. Gamma ray spectroscopy at JET has provided valuable diagnostic information on fast fuel as well as fusion product ions. Improvements of these measurements are needed to fully exploit the flux increase provided by future high power experiments at JET and ITER. Limiting aspects are, for instance, the count rate capability due to a high neutron/gamma background combined with slow detector response and a modest energy resolution due to the low light yield of the scintillators. This paper describes the solutions developed for achieving higher energy resolution, signal to background, and time resolution. The detector design is described based on the new BrLa3 scintillator crystal. The paper will focus on hardware development, including a photomultiplier tube capable of stable operation at counting rate as high as 1 MHz, the magnetic shielding, and the fast digital data acquisition system.

Successful conservative treatment of osteoradionecrosis of the mandible associated with pathological fracture

Treatment of patients with osteoradionecrosis (ORN) of the mandible associated with pathologic fractures usually consists of a continuity resection of the mandible, leading to severe impairment of the patient's health and quality of life. Conservative treatment may be alternatively attempted; however, it is not usually employed. Here, we report a successful conservative treatment of ORN associated with pathologic fracture. A 48-year-old black man who had undergone radiotherapy for a squamous cell carcinoma in the tongue 6 years previously sought care complaining of facial swelling and draining episodes. Since the patient was fiercely resistant to any kind of hospital-based therapy, a conservative approach was proposed. Daily irrigations with 2% potassium iodate, followed by 3% oxygenated water, were performed by the patient at his house. In addition, local cleaning and debridement were weekly performed at our dental clinic. Systemic antibiotics were also administered. Throughout the therapy course, bone fragments were spontaneously exfoliated. Resolution of the ulcer and fracture was observed after 6 weeks of treatment. This report shows that ORN may be conservatively managed in specific situations, with good cosmetic and functional

Mouse embryonic stem cell expansion in a microcarrier-based stirred culture system

Embryonic stem (ES) cells have the ability to differentiate in vitro into a wide variety of cell types with potential applications for tissue regeneration. However, a large number of cells are required, thus strengthening the need to develop large-scale systems using chemically defined media for ES cell production and/or controlled differentiation. In the present studies, a stirred culture system (i.e. spinner flask) was used to scale-up mouse ES (mES) cell expansion in serum-containing (DMEM/FBS) or serum-free medium, both supplemented with leukemia inhibitory factor (LIF), using either Cytodex 3 or Cultispher S microcarriers. After 8 days, maximal cell densities achieved were (1.9+/-0.1), (2.6+/-0.7) and 3.5x10(6)cells/mL for Cytodex 3 in DMEM/FBS, Cultispher S in DMEM/FBS and Cultispher S in serum-free cultures, respectively, with fold increases of 38+/-2, 50+/-15 and 70. Both microcarriers were suitable to sustain mES cell expansion, though the macroporous Cultispher S seemed to be advantageous in providing a more protective environment against shear stress forces, which harmful effects are exacerbated in serum-free conditions. Importantly, mES cells expanded under stirred conditions using serum-free medium retained their pluripotency and the ability to commit to the neural lineage.

Spatial expression of two anti-inflammatory mediators, annexin 1 and galectin-1, in nasal polyposis

BACKGROUND

There is renewed interest in the role played by specific counter-regulatory mechanisms to control the inflammatory host response, poorly investigated in human pathology. Here, we monitored the expression of two anti-inflammatory mediators, annexin 1 and galectin-1, and assessed their potential link to glucocorticoids' (GCs) effective control of nasal polyposis (NP).

METHODS

Total patterns of mRNA and protein expression were analysed by quantitative real-time PCR (qPCR) and Western blotting analyses, whereas ultrastructural immunocytochemistry was used for spatial localization and quantification of each mediator, focusing on mast cells, eosinophils and epithelial cells.

RESULTS

Up-regulation of the annexin 1 gene, and down-regulation of galectin-1 gene, was detected in polypoid tissue compared with nasal mucosa. Patient treatment with betamethasone augmented galectin-1 protein expression in polyps. At the cellular level, control mast cells and eosinophils displayed higher annexin 1 expression, whereas marked galectin-1 immunolabelling was detected in the granule matrix of mast cells. Cells of glandular duct epithelium also displayed expression of both annexin 1 and galectin-1, augmented after treatment.

CONCLUSION

Mast cells and epithelial cells appeared to be pivotal cell types involved in the expression of both annexin 1 and galectin-1. It is possible that annexin 1 and galectin-1 could be functionally associated with a specific mechanism in NP and that GC exert at least part of their beneficial effects on the airway mucosa by up-regulating, in a specific cell target fashion, these anti-inflammatory agonists.

Two intermediates in the synthesis of decahydroisoquinolines with NMDA and AMPA receptor antagonist activity

In 6-methyl-N-(4-nitrobenzoyl)-5,6-dihydropyridin-2(1H)-one, C(13)H(12)N(2)O(4), (I), the piperidone ring is in a distorted half-chair conformation. In 8-methoxy-3-methyl-N-(4-nitrobenzoyl)-1,2,3,4,5,6,7,8-octahydroisoquinoline-1,6-dione, C(18)H(20)N(2)O(6), (II), the heterocyclic ring is in a slightly distorted half-boat conformation, while the other six-membered ring is in a distorted chair conformation. Compound (II) presents a strong intramolecular C-H...O hydrogen bond. In both (I) and (II), the molecules interact through C-H...O interactions.

[Knowledge, attitudes, and practices of Brazilian women treated in the primary health care system concerning sexually transmitted diseases]

An increase has been observed in the prevalence of HIV infection among Brazilian women in recent years. This study focused on women's knowledge, attitudes, and practices towards prevention of sexually transmitted diseases (STDs) in the primary health care system in Campinas, São Paulo. Of the 249 women interviewed, 10% reported condom use, while consistent use was reported by 7.6%. Although most women reported receiving information from television (87.6%), the quality of such information was insufficient to sensitize women as to their risk of exposure to STD. Most of the women reported physician confidence as an important factor. We conclude that women do not opt for condoms to prevent STD/AIDS, but as a contraceptive method. An instructive dialogue on STD/AIDS should be adopted during physician consultation, and the kind and quality of information should be updated to foster compliance with safer sex practices by the population.

Dominance of ErbB-1 heterodimers in lung epithelial cells overexpressing ErbB-2. Both ErbB-1 and ErbB-2 contribute significantly to tumorigenicity

This article examines differential expression and heterodimer formation of ErbB family members in tumorigenic and nontumorigenic human bronchial epithelial cells (HBECs). This cell system was developed previously as a model for lung adenocarcinoma by overexpression of c-erbB-2 in nontumorigenic, T antigen-immortalized HBECs. Earlier studies demonstrated that a tumorigenic clone from T antigen-immortalized nontumorigenic cells overexpressing ErbB-2 endogenously produced high levels of transforming growth factor (TGF)-alpha, and that reducing TGF-alpha by 93% eliminated tumorigenicity. In the present report, comparison of ErbB species between the tumorigenic cells (E6T) and their nontumorigenic derivatives (E6TA) demonstrated all four receptors in both cell types. However, in E6TA cells, ErbB-3 and -4 were present primarily in ErbB-1 heterodimers, suggesting that ErbB-1 is a preferred heterodimer partner within this cell system, expressing endogenous ErbB receptors and ligands and overexpressing ErbB-2. The ErbB-1/-2 species was present at high levels in E6T and absent in E6TA cells. Mitogen-activated protein kinase activity was elevated in E6T relative to E6TA. Elevated activity was eliminated by blocking surface expression of either ErbB-1 or ErbB-2. Endoplasmic reticulum trapping of ErbB-1 eliminated tumorigenicity, whereas ErbB-2 internalization was selected against during tumor formation. These data demonstrate the importance of TGF-alpha-mediated signaling through the ErbB-1/-2 heterodimer in development of the tumorigenic phenotype. This work further suggests that ErbB-3 and -4 species may also contribute to tumorigenic conversion and that their expression levels may be increased by signaling initiated by TGF-alpha.

Evaluation of in vitro toxicity of N,N-dimethyl-2-propen-1-amines isomers

The trypanocidal activities of cis-3-(4'-bromo[1,1'-biphenyl]-4-yl)- 3-(phenyl)-N,N-dimethyl-2-propen-1-amine (Vb) and cis-3-(4'-bromo[1,1'-biphenyl]-4-yl)-3-(4-bromophenyl)-N,N-dimethyl-2- propen-1-anine (Vg) appeared 6.3 and 3.5 fold more active than the trans-isomers, respectively. Multi-endpoints for toxicity were also applied. Neutral red uptake (NRU), tetrazolium salt reduction (MTT), DNA content on V79 fibroblast cell culture and acute toxicity von E. coli were measured. The IC50 through DNA contents was lower for the cis-isomers in both series of compounds 5b: 7.8 microM and 5g: 5.2 microM). NRU values for derivative 5b in isomeric mixture shows the same value as the isolated isomers however, in the case of 5g a more significant toxicity of the cis-isomer was found. MTT values show that 5g is more toxic than 5b. In both cases, the acute toxicity of the trans-isomers was higher than that of the cis-isomers.

Production of epidermal growth factor related ligands in tumorigenic and benign human lung epithelial cells

We recently demonstrated that human lung epithelial cells, overexpressing ErbB-2, formed tumors in nude mice only when high levels of transforming growth factor alpha (TGFalpha) were produced. Cells transfected with a TGFalpha antisense vector failed to form tumors in nude mice. In order to further evaluate the importance, for tumorigenicity, of TGFalpha and its stimulation of ErbB family signalling, the production of other EGF family growth factors by these human lung epithelial cells was studied. We demonstrate for the first time that both tumorigenic and non-tumorigenic human lung epithelial cells produced, in addition to TGFalpha, amphiregulin, betacellulin, heparin-binding EGF and heregulin. These data suggest that human lung epithelial cells have the potential for multifactorial modulation of ErbB receptor family signalling through control of ligand as well as receptor production. In this system, the probable importance of TGFalpha-stimulated signaling for tumorigenicity is supported by its 13-fold higher production in tumorigenic as compared with non-tumorigenic cells and the 2-fold or lower differences observed in production of the other epidermal growth factor (EGF) family ligands.

Characterization of T cell ligands for uromodulin: a possible role in costimulation

In this study, we demonstrate that uromodulin (UMN) is a costimulator of T cells and characterize the T cell ligand which might mediate its costimulatory effect. UMN is an 85-kDa human urinary glycoprotein which is better known for its ability to suppress antigen-induced proliferation of peripheral blood mononuclear cells. It also has a mitogenic effect on peripheral blood cells, which has not been investigated. In this study, costimulation of T cells by UMN is observed only in the absence of B cells and antigen-specific antiserum. Using ligand binding assays we also demonstrate a specific receptor for UMN on peripheral blood T cells and T cell lines (Kd of 10(-8)). We describe two uromodulin binding proteins of approximate M(r) 35 and 55 kDa, isolated from detergent extract of T cells, either of which may represent a receptor for UMN or an associated signal transduction molecule involved in the stimulatory effect of UMN on T cells. Finally, we demonstrate a similar protein in a renal cell line, which may clarify the renal role of UMN.