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1.
Poult Sci ; 96(7): 2064-2073, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28339726

RESUMEN

Peas are traditionally used as a protein source for poultry. However, peas contain antinutritional factors (ANF), which are associated with the initiation of local and systemic immune reactions. The current study examined the effect of feeding raw or differently processed peas in comparison with feeding a soybean meal (SBM) based control diet (C) on the gut mucosal immune system of broilers in a 35 day feeding trial. In six replicates, a total of 360 one-day-old male broilers were randomly allocated to four different groups receiving C, or three treatment diets containing raw, fermented, and enzymatically pre-digested peas, each supplying 30% of required crude protein. After slaughtering, jejunal samples were taken for immunohistochemical, flow cytometric, and gene expression analyses. Investigations were focused on the topological distribution of intraepithelial leukocytes (villus tip, villus mid, and crypt region) as well as on the further characterization of the different intraepithelial lymphocytes (IEL) and concomitant pro- and anti-inflammatory cytokines. Broilers receiving the raw or processed pea diets had higher numbers of intraepithelial CD45+ leukocytes in the tip (P = 0.004) and mid region (P < 0.001) of villi than birds fed C. Higher numbers of intraepithelial CD3+ lymphocytes were found in the villus tip (P = 0.002) and mid region (P = 0.003) of birds fed raw or processed pea containing diets in comparison with those fed C. The flow cytometric phenotyping showed a similar relative distribution of IEL among the feeding groups. The expression of intestinal pro- and anti-inflammatory cytokines was affected by feeding the different diets only to a minor extent. To conclude, feeding of diets formulated with raw and processed peas in comparison with feeding a SBM control diet initiated mucosal immune responses in the jejunum of broilers indicated by a quantitative increase of intraepithelial T cells. Further research is needed in order to ascertain the specific factors which are responsible for observed local immune reactions and how these local reactions might affect the immune status and health of broilers.


Asunto(s)
Alimentación Animal/análisis , Pollos/inmunología , Glycine max/química , Inmunidad Mucosa/efectos de los fármacos , Pisum sativum/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Fermentación , Manipulación de Alimentos , Yeyuno/inmunología , Leucocitos/inmunología , Distribución Aleatoria
2.
Allergy ; 70(7): 775-83, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25831972

RESUMEN

BACKGROUND: The introduction of pegylated interferon (PEG-IFN)-α in the treatment of chronic hepatitis C has led to an increase in sustained virological response. Despite reduced immunogenicity of the pegylated form in comparison with native interferon (IFN)-α, a high frequency of adverse cutaneous reactions has been reported with pegylated IFN-α. Here, we aimed to investigate the immunological mechanisms underlying pegylated IFN-α-induced drug eruptions. METHODS: Hepatitis C patients suffering from drug eruptions in association with administration of pegylated interferons were enrolled in the study (n = 22). Subjects were tested for sensitivity to pegylated IFN-α2a , pegylated IFN-α2b , or ribavirin using intradermal, scratch, and/or patch tests, as well as lymphocyte activation tests (LATs). Skin biopsies obtained from pegylated IFN-α-associated exanthemas, as well as from localized inflammatory skin reactions at pegylated IFN-α injection sites, were analyzed for the expression of relevant chemokines by quantitative real-time PCR and immunohistochemistry. RESULTS: A subset of patients suffering from pegylated IFN-α-associated exanthemas displayed positive intradermal tests to PEG-IFNs but not to conventional IFN (11/22). In selected patients, this observation correlated with the presence of pegylated IFN-specific T cells (3/11). Chemokine profiles of inflammatory skin reactions at the injection sites reflected an IFN-α-signature, whereas lesional skin of exanthemas showed induction of TH2-associated chemokines. CONCLUSIONS: Our results indicate that specific sensitizations are one cause of exanthemas under therapy with PEG-IFNs. Clinical proof-of-concept analyses demonstrate that affected patients may benefit from a switch to conventional, nonpegylated drugs, enabling IFN-α therapy continuation without drug-associated skin eruptions.


Asunto(s)
Antivirales/efectos adversos , Erupciones por Medicamentos/etiología , Interferón-alfa/efectos adversos , Polietilenglicoles/efectos adversos , Antivirales/uso terapéutico , Citocinas/genética , Citocinas/metabolismo , Erupciones por Medicamentos/diagnóstico , Expresión Génica , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/metabolismo , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Activación de Linfocitos , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Piel/patología , Pruebas Cutáneas , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
3.
Eur Rev Med Pharmacol Sci ; 17(17): 2293-4, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24065220

RESUMEN

Pneumatosis intestinalis is an uncommon condition characterized by the presence of gas in the bowel wall. We present the case of a 49-year-old man admitted to our Clinic for his 4 day long haematochezia. Colonoscopy revealed pneumatosis coli as a cause of the lower gastrointestinal bleeding. A wide range of diagnostic methods didn't show any underlying disease related to the bleeding, other than the presence of gas. Patient is reported in order to draw attention to the primary pneumatosis coli presented as a rare cause of haematochezia.


Asunto(s)
Colonoscopía , Hemorragia Gastrointestinal/etiología , Neumatosis Cistoide Intestinal/diagnóstico , Estudios de Seguimiento , Hemorragia Gastrointestinal/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Neumatosis Cistoide Intestinal/complicaciones
4.
Dtsch Med Wochenschr ; 138(27): 1425-30, 2013 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-23801265

RESUMEN

The incidence of hepatocellular carcinoma (HCC) is increasing worldwide due to the growing number of hepatitis C related HCCs. In more than 80% of the patients, HCC arises in a cirrhotic liver. Furthermore, more than half of the patients have an advanced Child-Pugh score or an inoperable tumor stage at the initial diagnosis. Recommendations for the treatment of HCC by national and international guidelines rely on the BCLC ("Barcelona Clinic for Liver Cancer") algorithm. Depending on the stage of liver function and tumor disease it recommends resection, liver transplantation, radiofrequency thermal ablation (RFA), transarterial chemoembolisation (TACE), systemic therapy with sorafenib or best supportive care, but does neither take into consideration combination of therapies nor new therapy modalities. However, there is increasing evidence that combinations i. e. sorafenib with TACE or combination of locoregional techniques enhance effectivity and tumor control compared to monotherapies. TACE with drug-eluting beads, selective internal radiotherapy (SIRT) and new locoregional therapy procedures like microwave ablation (MWA) are further promising therapeutic approaches. Patients with HCC should be discussed in a local tumor board in order to provide the optimal and most individual way of treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/terapia , Ablación por Catéter/tendencias , Quimioembolización Terapéutica/tendencias , Neoplasias Hepáticas/terapia , Trasplante de Hígado/tendencias , Radioterapia/tendencias , Terapia Combinada/tendencias , Humanos
5.
Z Gastroenterol ; 49(12): 1535-42, 2011 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-22139877

RESUMEN

Urea cycle defects belong to the most common metabolic disorders with a cumulative incidence of 1:8000. A common trait of urea cycle defects is a disturbed detoxification of ammonia leading to hyperammonemia in the event of a high nitrogen load. Most patients develop symptoms in the neonatal period or in infancy, e. g. vomiting, seizures and disturbed consciousness. Depending on the affected enzyme and its residual activity, patients differ in the age at first presentation, the character and severity of symptoms and in the susceptibility to metabolic derangement. The presence of hyperammonemia and an altered plasma amino acid profile give the essential diagnostic clues. Since modern therapeutic measures have prolonged the life expectancy of these patients and provided the possibility of a first presentation in adulthood, patients with urea cycle defects have become an increasing challenge in internal medicine. The reported case series illustrates the heterogeneous clinical course of these disorders from childhood to adulthood.


Asunto(s)
Trastornos Innatos del Ciclo de la Urea/diagnóstico , Trastornos Innatos del Ciclo de la Urea/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
6.
Eur J Med Res ; 16(5): 213-6, 2011 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-21719394

RESUMEN

INTRODUCTION: Perforation of the gall bladder represents a rare, but life-threatening complication of cholecystitis. Clinical presentation may vary between severe peritonism in acute perforation and absence of symptoms in subacute or chronic progression of perforation. Abdominal imaging like ultrasound or CT-scan are important tools for immediate diagnose of gall bladder perforation. CASE PRESENTATION: We report a case of a 30-year old female patient with end-stage kidney disease treated by continuous ambulatory peritoneal dialysis (CAPD) who was admitted to the emergency room with fever and mild abdominal pain. A type II gall bladder perforation by a solitary gall stone with development of a liver abscess was detected by abdominal ultrasound. CONCLUSION: Gall bladder perforations are rare but have to be considered in patients with abdominal pain and fever. Abdominal ultrasound is a reliable tool to establish diagnosis.


Asunto(s)
Enfermedades de la Vesícula Biliar/etiología , Cálculos Biliares/complicaciones , Absceso Hepático/etiología , Diálisis Peritoneal Ambulatoria Continua , Adulto , Femenino , Humanos , Rotura Espontánea
7.
Z Gastroenterol ; 48(8): 813-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20687016

RESUMEN

BACKGROUND/AIMS: Epidemiology, clinical features and long term-course of chronic hepatitis D were addressed in a non-endemic Central European area. METHODS: Sixty-seven patients with chronic hepatitis D were identified among 1307 HBsAg carriers at the university hospital Düsseldorf during two decades (1989 - 2008) and followed for a mean of 7 +/- 6 years. Forty-one of these were treated with IFN-alfa for at least six months. RESULTS: Hepatitis D prevalence increased from 4.1 to 6.2 % among HBsAg carriers during the two decades (p < 0.06). Patients originating from the former Soviet Union (32.1 vs. 46.2 %) and Africa (0 vs. 17.9 %) became more frequent whereas the prevalence of patients from Southern Europe declined (46.5 vs.17.9 % p < 0.03). The time span between the diagnosis of hepatitis B and D was 4.8 +/- 7 years (p < 0.0001). A sustained virological response to interferon-alfa was achieved in 19.5 % of the patients. The yearly incidence rates for death, HCC and complications were 3.2 %, 2.7 % and 8 % among patients with liver cirrhosis. Estimated survival and complication-free survival during 12 years were 72 % and 45 % in cirrhotic compared to 100 % in non-cirrhotic patients (p < 0.008 and p < 0.0001, respectively). CONCLUSION: Hepatitis D in western Germany appears to be on the increase and has a migration background that should be considered in clinical practice. Clinical outcome and response to IFN are as poor as in endemic regions, indicating the need to improve early diagnosis.


Asunto(s)
Enfermedades Transmisibles Emergentes/mortalidad , Brotes de Enfermedades/estadística & datos numéricos , Hepatitis D Crónica/mortalidad , Servicios de Salud para Estudiantes/estadística & datos numéricos , Adolescente , Adulto , Anciano , Niño , Femenino , Alemania/epidemiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Prevalencia , Estudios Retrospectivos , Análisis de Supervivencia , Tasa de Supervivencia , Adulto Joven
8.
Vet Immunol Immunopathol ; 119(1-2): 137-41, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17659354

RESUMEN

A panel of commercially available anti-human mab was screened for cross-reactivity on chicken cells. All mab were screened at least twice on PBL collected from two different chicken lines. Out of the 377 mab tested, only two consistently reacted with subpopulations of PBL. The mab HUH73A reactive with CD11a was detected on all lymphocytes. In contrast, the mab 23C6 obtained from Serotec and reactive with an epitope formed by humanVbeta3 integrin chains (CD51/CD61) reacted with all thrombocytes, but not with other cells. In double immunofluorescence analyses, the 23C6+ cells were found to coexpress the CD45 antigen and the chicken thrombocyte marker K1. The chicken genes encoding CD51 and CD61 were analyzed by database mining. The CD51 gene is encoded by a 43 kb region containing 30 exons on chicken chromosome 7, whereas the 16 kb CD61 gene consisted of 15 exons and was localized to chromosome 27. In conclusion, the mab 23C6 is a useful reagent to identify chicken thrombocytes.


Asunto(s)
Plaquetas/inmunología , Pollos/inmunología , Integrina alfaV/análisis , Integrina beta3/análisis , Animales , Anticuerpos Monoclonales/inmunología , Reacciones Cruzadas , Humanos , Inmunofenotipificación , Integrina alfaV/genética , Integrina beta3/genética
9.
Vet Rec ; 155(11): 326-9, 2004 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-15470968

RESUMEN

Eighty-nine free-living birds of prey and owls were examined and blood samples and radiographs were taken. In addition, 126 specimens of renal tissue were obtained without complications, with a mean postbiopsy haemorrhage time of 67 seconds. On average, the samples were 2.2 mm long, 1.3 mm wide and 1.0 mm deep and they all contained proximal and distal tubuli and from one to 89 glomeruli; 49 of them contained from one to four intralobular veins, and on average each sample contained 10.7 per cent air sac tissue; 113 of the 126 samples could be evaluated histologically.


Asunto(s)
Enfermedades de las Aves/diagnóstico , Enfermedades Renales/veterinaria , Rapaces , Animales , Animales Salvajes , Biopsia/veterinaria , Enfermedades de las Aves/sangre , Enfermedades de las Aves/diagnóstico por imagen , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/patología , Análisis Químico de la Sangre/veterinaria , Femenino , Alemania/epidemiología , Enfermedades Renales/diagnóstico , Masculino , Radiografía/veterinaria , Estrigiformes
10.
Artículo en Inglés | MEDLINE | ID: mdl-15030602

RESUMEN

An enzyme-linked immunosorbent assay (ELISA) for the detection of Marek's disease virus (MDV)-specific antibodies was developed. Chicken embryo cells (CEC) or chicken kidney cells (CKC) were infected with MDV vaccine strain CVI988/Rispens, and infected-cell lysates were prepared at day 5 post-infection by freeze-thawing. Uninfected-cell lysates served as negative controls. Sera were used at a 1 : 100 dilution and were added in parallel to wells containing the infected and uninfected cell lysates. The optical densities at 492 nm (OD(492 nm)) were measured after detection of bound chicken antibodies with anti-chicken IgG peroxidase conjugate and colour reactions using o-phenylenediamine (OPD) as a substrate. The best results concerning the signal-to-noise ratio were obtained by using CKC cells rather than CEC for antigen preparation. The OD(492 nm) of plasma or serum samples with infected CKC was <0.02 when samples of unvaccinated and unchallenged maternal antibody-negative white leghorn chickens were tested. Sera and plasma samples of positive control birds exhibited OD(492 nm) of <0.01 when tested with uninfected CKC. The assay was used to monitor a trial that compared experimental BAC DNA vaccines and a commercial vaccine. Sustained seroconversion and antibody titers that were constantly rising until day 84 after vaccination (71 days after challenge) was observed only when chickens did not develop Marek's disease. In contrast, chickens developing the disease mounted marginal and short-lived antibody titers only. We conclude that the developed ELISA may be a valuable tool for the evaluation of the efficacy of MDV vaccination under experimental but possibly also under field conditions.


Asunto(s)
Pollos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Mardivirus/inmunología , Vacunas contra la Enfermedad de Marek/inmunología , Enfermedad de Marek/prevención & control , Animales , Anticuerpos Antivirales/análisis , Ensayo de Inmunoadsorción Enzimática/normas , Mardivirus/aislamiento & purificación , Enfermedad de Marek/diagnóstico , Valor Predictivo de las Pruebas , Vacunación/veterinaria
11.
Berl Munch Tierarztl Wochenschr ; 115(1-2): 43-52, 2002.
Artículo en Alemán | MEDLINE | ID: mdl-11852683

RESUMEN

In the present paper a general overview on parasites in birds of prey and owls is given. This part is followed by a study investigating the prevalences and species of parasites in free-ranging birds of prey and owls in Berlin and Brandenburg State, Germany. Over a one year period, 84 birds of prey and owls of the following species were examined for the presence of endo- and ectoparasites: Common Buzzard (Buteo buteo) (n = 32), Kestrel (Falco tinnunculus) (n = 20), Sparrowhawk (Accipiter nisus) (n = 9), Goshawk (Accipiter gentilis) (n = 8), Black Kite (Milvus migrans) (n = 4), Peregrine Falcon (Falco peregrinus) (n = 3), Marsh Harrier (Circus aeruginosus) (n = 1), White-tailed-Sea Eagle (Haliaeetus albicilla) (n = 1), Tawny Owl (Strix aluco) (n = 4), Long-eared Owl (Asio otus) (n = 1) and Barn Owl (Tyto alba) (n = 1). In 97.6% of the cases, ectoparasites (feather mites and hippoboscid flies) were found. Especially eyasses (93.3%) were positive for hippoboscid flies. Trichomonas was detected in 28.6% of all birds of prey and owls examined. A prevalence of 100% was established in the Sparrow Hawks as well as Peregrine Falcons. Leucozytozoon sp. and Hemoproteus sp. as blood parasites were found in 26.9% of the birds in total. Common Buzzards showed the highest prevalence (44.8%). 58.3% of birds examined were positive for endoparasites. Flukes were found in 16.7%, tapeworms in 14.3%, round-worms in 48.8% and acanthocephales in 2.4% of the cases. Interestingly, Tylodelphis clavata (in a Common Buzzard) and Hovorkonema variegatum (in a Goshawk) were found for the first time in raptors. The results of this study underline the importance of a parasitological examination in the process of raptor rehabilitation.


Asunto(s)
Enfermedades de las Aves/epidemiología , Parásitos/aislamiento & purificación , Enfermedades Parasitarias en Animales/epidemiología , Rapaces/parasitología , Estrigiformes/parasitología , Animales , Enfermedades de las Aves/parasitología , Alemania/epidemiología , Parásitos/clasificación
12.
Int Immunol ; 13(6): 757-62, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11369702

RESUMEN

Non-mammalian NK cells have not been characterized in detail; however, their analysis is essential for the understanding of the NK cell receptor phylogeny. As a first step towards defining chicken NK cells, several tissues were screened for the presence of NK cells, phenotypically defined as CD8(+) cells lacking T- or B-lineage specific markers. By this criteria, approximately 30% of CD8(+) intestinal intraepithelial lymphocytes (IEL), but <1% of splenocytes or peripheral blood lymphocytes were defined as NK cells. These CD8(+)CD3(-) IEL were used for the generation of the 28-4 mAb, immunoprecipitating a 35-kDa glycoprotein with a 28-kDa protein core. The CD3 and 28-4 mAb were used to separate IEL into CD3(+) IEL T cells and 28-4(+) cells, both co-expressing the CD8 antigen. During ontogeny, 28-4(+) cells were abundant in the IEL and in the embryonic spleen, where two subsets could be distinguished according to their CD8 and c-kit expression. Most importantly, 28-4(+) IEL lysed NK-sensitive targets, whereas intestinal T cells did not have any spontaneous cytolytic activity. These results define two major, phenotypically and functionally distinct IEL subpopulations, and imply an important role of NK cells in the mucosal immune system.


Asunto(s)
Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Células Asesinas Naturales/citología , Subgrupos Linfocitarios/citología , Linfocitos T/citología , Animales , Animales Endogámicos , Anticuerpos Monoclonales/metabolismo , Antígenos de Diferenciación de Linfocitos T/inmunología , Antígenos de Diferenciación de Linfocitos T/metabolismo , Antígenos de Superficie/inmunología , Antígenos de Superficie/metabolismo , Complejo CD3/inmunología , Complejo CD3/metabolismo , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/inmunología , Línea Celular , Línea Celular Transformada , Pollos , Mucosa Intestinal/metabolismo , Células Asesinas Naturales/inmunología , Subgrupos Linfocitarios/inmunología , Bazo/citología , Bazo/embriología , Linfocitos T/inmunología
13.
J Interferon Cytokine Res ; 21(12): 993-1010, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11798457

RESUMEN

Targeted disruptions of the mouse genes for cytokines, cytokine receptors, or components of cytokine signaling cascades convincingly revealed the important roles of these molecules in immunologic processes. Cytokines are used at present as drugs to fight chronic microbial infections and cancer in humans, and they are being evaluated as immune response modifiers to improve vaccines. Until recently, only a few avian cytokines have been characterized, and potential applications thus have remained limited to mammals. Classic approaches to identify cytokine genes in birds proved difficult because sequence conservation is generally low. As new technology and high throughput sequencing became available, this situation changed quickly. We review here recent work that led to the identification of genes for the avian homologs of interferon-alpha/beta (IFN-alpha/beta) and IFN-gamma, various interleukins (IL), and several chemokines. From the initial data on the biochemical properties of these molecules, a picture is emerging that shows that avian and mammalian cytokines may perform similar tasks, although their primary structures in most cases are remarkably different.


Asunto(s)
Pollos/inmunología , Citocinas/fisiología , Adyuvantes Inmunológicos/farmacología , Secuencia de Aminoácidos , Animales , Aves/genética , Aves/inmunología , Quimiocinas/genética , Quimiocinas/fisiología , Pollos/genética , Citocinas/genética , Citocinas/farmacología , Modelos Animales de Enfermedad , Humanos , Interferones/genética , Interferones/fisiología , Interleucinas/genética , Interleucinas/fisiología , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Virosis/inmunología
14.
Eur J Immunol ; 30(10): 2775-81, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11069057

RESUMEN

The TCR/CD3 complex of a cold-blooded vertebrate, the amphibian Xenopus laevis, was biochemically characterized with a cross-reactive polyclonal antiserum recognizing a conserved epitope in the cytoplasmic domain of CD3E. The specificity and utility of this reagent was validated by Western blot analysis and immunoprecipitation of the well-characterized chicken TCR/CD3 complex. Cross-reactivity with the X. laevis CD3E protein was demonstrated by specific staining of sorted CD8+ cells. Immunohistology on both tadpoles and adult tissues suggests this antiserum will be instrumental in the localization of Xenopus T cells and most likely NK cells. Double staining of tissue sections with an anti-CD8 monoclonal antibody confirmed that this staining is specific. The antiserum was also used for the biochemical analyses of X. laevis TCR/CD3 complex. The 75-kDa alphabeta TCR heterodimer could be separated into a 40-kDa acidic TCR alpha chain and a 35-kDa basic TCR beta chain. Two CD3 proteins, both comigrating at approximately 19 kDa, were associated with the TCR heterodimer. Removal of N-linked carbohydrates yielded CD3 proteins of 19 kDa and 16.5 kDa, most likely representing the CD3epsilon and CD3gamma/delta homologues, respectively. An additional band of 110 kDa represents a multimeric complex of the TCR heterodimer covalently linked to a CD3 dimer. These properties of the Xenopus TCR/CD3 complex substantiate a stepwise evolutionary model for the CD3 protein family.


Asunto(s)
Evolución Molecular , Complejo Receptor-CD3 del Antígeno de Linfocito T/análisis , Xenopus laevis/inmunología , Secuencia de Aminoácidos , Animales , Complejo CD3/química , Complejo CD3/inmunología , Secuencia de Consenso , Reacciones Cruzadas , Dimerización , Epítopos/inmunología , Glicosilación , Sueros Inmunes , Larva , Sustancias Macromoleculares , Modelos Biológicos , Datos de Secuencia Molecular , Procesamiento Proteico-Postraduccional , Estructura Terciaria de Proteína , Complejo Receptor-CD3 del Antígeno de Linfocito T/genética , Complejo Receptor-CD3 del Antígeno de Linfocito T/inmunología , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Bazo/citología , Timoma/patología , Neoplasias del Timo/patología , Xenopus laevis/genética , Xenopus laevis/crecimiento & desarrollo
17.
J Immunol ; 164(2): 879-83, 2000 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10623835

RESUMEN

The three CD3 components of the TCR complex are encoded as clustered genes in mammals. The evolution of such a multimeric complex is likely to occur stepwise. The chicken CD3 cluster was entirely sequenced, and, in contrast to mammals, only two chicken CD3 genes were found to be physically linked to the unrelated genes HZW10 and epithelial V-like Ag flanking both sides of the CD3 cluster. Biochemical analyses of CD3 immunoprecipitates confirmed the presence of only two CD3 proteins and revealed an essential role for CD3gammadelta glycosylation during assembly. Functional analyses indicated that the chicken TCR/CD3 complex was efficiently down-regulated by phorbol ester treatment, demonstrating the integrity of a CD3gamma-like cytoplasmic internalization motif. These data argue for a stepwise CD3 evolution, with major differences in the TCR/CD3 structure between mammalian and nonmammalian vertebrates setting a basis for the understanding of the CD3 phylogeny and proving the ancestral nature of the CD3gammadelta protein.


Asunto(s)
Complejo CD3/genética , Evolución Molecular , Familia de Multigenes/inmunología , Secuencias de Aminoácidos , Animales , Complejo CD3/química , Pollos , Dimerización , Regulación hacia Abajo/inmunología , Marcadores Genéticos , Humanos , Datos de Secuencia Molecular , Receptores de Antígenos de Linfocitos T/biosíntesis , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/genética
18.
Nature ; 401(6756): 923-5, 1999 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-10553909

RESUMEN

Here we report the sequence of the region that determines rapid allograft rejection in chickens, the chicken major histocompatibility complex (MHC). This 92-kilobase region of the B locus contains only 19 genes, making the chicken MHC roughly 20-fold smaller than the human MHC. Virtually all the genes have counterparts in the human MHC, defining a minimal essential set of MHC genes conserved over 200 million years of divergence between birds and mammals. They are organized differently, with the class III region genes located outside the class II and class I region genes. The absence of proteasome genes is unexpected and might explain unusual peptide-binding specificities of chicken class I molecules. The presence of putative natural killer receptor gene(s) is unprecedented and might explain the importance of the B locus in the response to the herpes virus responsible for Marek's diseases. The small size and simplicity of the chicken MHC allows co-evolution of genes as haplotypes over considerable periods of time, and makes it possible to study the striking MHC-determined pathogen-specific disease resistance at the molecular level.


Asunto(s)
Pollos/genética , Complejo Mayor de Histocompatibilidad , Secuencia de Aminoácidos , Animales , Línea Celular , Pollos/inmunología , Evolución Molecular , Genes MHC Clase I , Genes MHC Clase II , Células Asesinas Naturales , Datos de Secuencia Molecular , Receptores Inmunológicos/genética , Recombinación Genética , Homología de Secuencia de Aminoácido
19.
J Immunol ; 163(7): 3858-66, 1999 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-10490985

RESUMEN

Mammalian TCR delta genes are located in the midst of the TCR alpha gene locus. In the chicken, one large V delta gene family, two D delta gene segments, two J delta gene segments, and one C delta gene have been identified. The TCR delta genes were deleted on both alleles in alpha beta T cell lines, thereby indicating conservation of the combined TCR alpha delta locus in birds. V alpha and V delta gene segments were found to rearrange with one, both or neither of the D delta segments and either of the two J delta segments. Exonuclease activity, P-addition, and N-addition during VDJ delta rearrangement contributed to TCR delta repertoire diversification in the first embryonic wave of T cells. An unbiased V delta 1 repertoire was observed at all ages, but an acquired J delta 1 usage bias occurred in the TCR delta repertoire. The unrestricted combinatorial diversity of relatively complex TCR gamma and delta loci may contribute to the remarkable abundance of gamma delta T cells in this avian representative.


Asunto(s)
Genes Codificadores de la Cadena alfa de los Receptores de Linfocito T , Genes Codificadores de la Cadena delta de los Receptores de Linfocito T , Receptores de Antígenos de Linfocitos T alfa-beta/química , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T gamma-delta/química , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Pollos , Embrión no Mamífero/metabolismo , Eliminación de Gen , Regulación de la Expresión Génica/inmunología , Reordenamiento Génico de la Cadena alfa de los Receptores de Antígenos de los Linfocitos T , Reordenamiento Génico de la Cadena delta de los Receptores de Antígenos de los Linfocitos T , Humanos , Ratones , Datos de Secuencia Molecular , Conejos , Receptores de Antígenos de Linfocitos T gamma-delta/biosíntesis , Receptores de Antígenos de Linfocitos T gamma-delta/aislamiento & purificación , Subgrupos de Linfocitos T/metabolismo , Transcripción Genética/inmunología
20.
J Immunol ; 162(10): 5685-94, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10229800

RESUMEN

The thymus is colonized by circulating progenitor cells that differentiate into mature T cells under the influence of the thymic microenvironment. We report here the cloning and function of the avian thymocyte Ag ChT1, a member of the Ig superfamily with one V-like and one C2-like domain. ChT1-positive embryonic bone marrow cells coexpressing c-kit give rise to mature T cells upon intrathymic cell transfer. ChT1-specific Ab inhibits T cell differentiation in embryonic thymic organ cultures and in thymocyte precursor cocultures on stromal cells. Thus, we provide clear evidence that ChT1 is a novel Ag on early T cell progenitors that plays an important role in the early stages of T cell development.


Asunto(s)
Antígenos CD5/inmunología , Inmunoglobulinas/inmunología , Linfocitos T/citología , Linfocitos T/inmunología , Timo/inmunología , Secuencia de Aminoácidos , Animales , Antígenos de Superficie/genética , Secuencia de Bases , Trasplante de Médula Ósea , Antígenos CD5/genética , Diferenciación Celular , Embrión de Pollo , Pollos , Clonación Molecular , ADN Complementario/genética , Células Madre Hematopoyéticas/inmunología , Inmunoglobulinas/genética , Tejido Linfoide/embriología , Tejido Linfoide/inmunología , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Técnicas de Cultivo de Órganos , Proteínas Proto-Oncogénicas c-kit/aislamiento & purificación , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Timo/citología , Timo/cirugía , Distribución Tisular
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