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1.
Am J Transplant ; 16(8): 2342-51, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26887344

RESUMEN

Improved diagnostic methods are needed for bronchiolitis obliterans syndrome (BOS), a serious complication after allogeneic hematopoietic cell transplantation (HCT) and lung transplantation. For protein candidate discovery, we compared plasma pools from HCT transplantation recipients with BOS at onset (n = 12), pulmonary infection (n = 16), chronic graft-versus-host disease without pulmonary involvement (n = 15) and no chronic complications after HCT (n = 15). Pools were labeled with different tags (isobaric tags for relative and absolute quantification), and two software tools identified differentially expressed proteins (≥1.5-fold change). Candidate proteins were further selected using a six-step computational biology approach. The diagnostic value of the lead candidate, matrix metalloproteinase 3 (MMP3), was evaluated by enzyme-linked immunosorbent assay in plasma of a verification cohort (n = 112) with and without BOS following HCT (n = 76) or lung transplantation (n = 36). MMP3 plasma concentrations differed significantly between patients with and without BOS (area under the receiver operating characteristic curve 0.77). Consequently, MMP3 represents a potential noninvasive blood test for diagnosis of BOS.


Asunto(s)
Biomarcadores/sangre , Bronquiolitis Obliterante/diagnóstico , Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Pulmón/efectos adversos , Metaloproteinasa 3 de la Matriz/sangre , Proteoma/análisis , Adulto , Anciano , Bronquiolitis Obliterante/sangre , Bronquiolitis Obliterante/etiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/etiología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Proteómica/métodos , Trasplante Homólogo , Adulto Joven
2.
Tissue Antigens ; 79(5): 359-66, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22489945

RESUMEN

Somatic mutations and genomic alterations are frequent events in the clonal evolution of hematologic malignancies. Recent studies have reported copy neutral loss of heterozygosity (LOH) for the mismatched human leukocyte antigen (HLA) haplotype in patients relapsed after haploidentical hematopoietic cell transplantation (HCT) for a hematologic malignancy. Herein, we report 15 cases of somatic mutations in the HLA genes of patients with a variety of hematologic diseases, including acute myelogenous leukemia, acute lymphocytic leukemia, chronic lymphocytic leukemia, chronic myeloid leukemia, myelodysplastic syndrome, and non-Hodgkin's lymphoma, encountered at our institute over the past decade. While two of the cases were identified in patient relapse specimens collected post-HCT, 13 cases were found in peripheral blood specimens submitted for HLA typing prior to transplantation. Ten patients exhibited acquired LOH for all or part of one HLA haplotype. Five other cases involved somatic mutations in the nucleotide sequences of common HLA-A or HLA-B alleles. Since they are not systematically evaluated prior to HCT, acquired mutations in HLA genes are likely under reported. Beyond the implications for accurate HLA typing and donor selection, alternations that result in the loss of HLA expression may allow escape from immune surveillance and adversely impact transplant outcome.


Asunto(s)
Antígenos HLA-A/genética , Antígenos HLA-B/genética , Neoplasias Hematológicas/genética , Leucemia/genética , Linfoma no Hodgkin/genética , Adulto , Niño , Haplotipos , Trasplante de Células Madre Hematopoyéticas , Prueba de Histocompatibilidad , Humanos , Pérdida de Heterocigocidad , Persona de Mediana Edad , Mutación , Polimorfismo Genético
3.
J Exp Med ; 161(6): 1513-24, 1985 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-3159820

RESUMEN

In previous studies (17-21), monoclonal antibody (mAb) 9.3 has been shown to react with a major population of human T cells, which include T4+ helper/inducer T cells and T8+ cytotoxic T cells. In this investigation, mAb 9.3 was shown to precipitate a disulfide-bonded dimer of a 44 kD polypeptide. Comodulation experiments showed that this molecule is not linked to T3/Ti or T11 antigens. mAb 9.3 was capable of inducing T cell proliferation in the presence of 12-o-tetradecanoyl phorbol-13-acetate (TPA). This effect was monocyte-independent. T cell activation with mAb 9.3 and TPA was associated with increases in interleukin 2(IL-2) receptor expression and IL-2 secretion. mAb 9.3 did not activate T cells, even with the addition of IL-1 or IL-2. Modulation of the T3 complex did not abolish mAb 9.3-induced T cell proliferation in the presence of TPA. These results suggest that the 9.3 antigen may serve as a receptor for an activation pathway restricted to a T cell subset.


Asunto(s)
Antígenos de Superficie/inmunología , Activación de Linfocitos , Linfocitos T/inmunología , Anticuerpos Monoclonales/inmunología , Complejo CD3 , Humanos , Técnicas In Vitro , Interleucina-1/inmunología , Interleucina-2/inmunología , Conformación Proteica , Receptores de Antígenos de Linfocitos T/inmunología , Receptores Inmunológicos , Linfocitos T/clasificación , Acetato de Tetradecanoilforbol/farmacología
4.
J Exp Med ; 172(6): 1691-700, 1990 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-2147949

RESUMEN

Fresh peripheral blood mononuclear cells exposed to alloantigen for 3-8 d in the presence of anti-CD3 antibodies showed no response after restimulation with cells from the original donor but remained capable of responding to third-party donors. Antigen-specific nonresponsiveness was induced by both nonmitogenic and mitogenic anti-CD3 antibodies but not by antibodies against CD2, CD4, CD5, CD8, CD18, or CD28. Nonresponsiveness induced by anti-CD3 antibody in mixed leukocyte culture was sustained for at least 34 d from initiation of the culture and 26 d after removal of the antibody. Anti-CD3 antibody also induced antigen-specific nonresponsiveness in cytotoxic T cell generation assays. Anti-CD3 antibody did not induce nonresponsiveness in previously primed cells. Nonresponsiveness induced by anti-CD3 did not appear to be associated with suppressor cell activation. Thus, co-stimulation of the T cell receptor-CD3 complex on unprimed T cells with a fluid phase anti-CD3 antibody and allogenic major histocompatibility complex antigens can induce either clonal anergy or clonal deletion. These results suggest novel approaches for achieving transplantation tolerance.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Isoantígenos/inmunología , Activación de Linfocitos , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Antígenos de Diferenciación de Linfocitos T/análisis , Complejo CD3 , Células Cultivadas , Humanos , Receptores de Antígenos de Linfocitos T/análisis , Linfocitos T Citotóxicos/inmunología
5.
J Exp Med ; 164(1): 345-50, 1986 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-3014039

RESUMEN

HLA-DR4, Dw4-associated haplotypes associated with IDDM and JRA were compared using genomic DNA restriction fragment analysis to distinguish among DQ beta and alpha alleles linked to DR4. DQ beta polymorphisms that subdivide the HLA-DQw3 specificity into DQ3.1 and 3.2 alleles were identified. More than 90% of DR4+ IDDM patients express one of these alleles, DQ3.2; restriction enzyme mapping indicates that the presence of this allele also accounts for the genomic fragment patterns previously reported in IDDM. Furthermore, haplo-identical siblings of DQ3.2 IDDM patients also carry the DQ3.2 allele, regardless of clinical presentation. In contrast, DR4+ JRA patients show no allelic preference at DQ beta, implicating different HLA genetic contributions in these two DR4-associated diseases.


Asunto(s)
Artritis Juvenil/inmunología , Diabetes Mellitus Tipo 1/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Alelos , Artritis Juvenil/genética , Secuencia de Bases , Enzimas de Restricción del ADN , Diabetes Mellitus Tipo 1/genética , Marcadores Genéticos , Genotipo , Antígenos HLA-DQ , Humanos , Fenotipo
6.
J Exp Med ; 177(1): 165-73, 1993 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-7678111

RESUMEN

The specificity of T lymphocyte activation is determined by engagement of the T cell receptor (TCR) by peptide/major histocompatibility complexes expressed on the antigen-presenting cell (APC). Lacking costimulation by accessory molecules on the APC, T cell proliferation does not occur and unresponsiveness to subsequent antigenic stimulus is induced. The B7/BB1 receptor on APCs binds CD28 and CTLA-4 on T cells, and provides a costimulus for T cell proliferation. Here, we show that prolonged, specific T cell hyporesponsiveness to antigenic restimulation is achieved by blocking the interaction between CD28 and B7/BB1 in human mixed leukocyte culture (MLC). Secondary T cell proliferative responses to specific alloantigen were inhibited by addition to the primary culture of monovalent Fab fragments of anti-CD28 monoclonal antibody (mAb) 9.3, which block interaction of CD28 with B7/BB1 without activating T cells. Hypo-responsiveness was also induced in MLC by CTLA4Ig, a chimeric immunoglobulin fusion protein incorporating the extracellular domain of CTLA-4 with high binding avidity for B7/BB1. Cells previously primed could also be made hyporesponsive, if exposed to alloantigen in the presence of CTLA4Ig. Maximal hyporesponsiveness was achieved in MLC after 2 d of incubation with CTLA4Ig, and was maintained for at least 27 d after removal of CTLA4Ig. Accumulation of interleukin 2 (IL-2) and interferon gamma but not IL-4 mRNA was blocked by CTLA4Ig in T cells stimulated by alloantigen. Antigen-specific responses could be restored by addition of exogenous IL-2 at the time of the secondary stimulation. Addition to primary cultures of the intact bivalent anti-CD28 mAb 9.3, or B7/BB1+ transfected CHO cells or exogenous IL-2, abrogated induction of hyporesponsiveness by CTLA4Ig. These data indicate that interaction of CD28 with B7/BB1 during TCR engagement with antigen is required to maintain T cell competence and that blocking such interaction can result in a state of T cell hyporesponsiveness.


Asunto(s)
Antígenos CD/fisiología , Antígenos de Diferenciación de Linfocitos T/fisiología , Antígenos de Superficie/fisiología , Isoantígenos/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Antígeno B7-1 , Antígenos CD28 , Antígenos CD4/análisis , Células CHO , Cricetinae , Humanos , Fragmentos Fab de Inmunoglobulinas/inmunología , Interleucina-2/farmacología , Ratones , Linfocitos T Citotóxicos/fisiología
7.
J Exp Med ; 141(6): 1464-9, 1975 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-1127385

RESUMEN

Herediatary C2-deficiency has been shown to be transmitted asn an autosomal recessive characteristic. Recent evidence indicates that some genetic factors involved in the control of the complement (C) system in both man and mice are governed by genes localized within the major histocompatibility regionmthis study describes a large pedigree of the paternal family of a C2-deficient patient with systemic lupus erythematosusl It is shown that this condition is transmitted as an autosomal recessive trait, the heterozygous carriers having approximately half normal levels of C2. Furthermore, this trait was shown to be inherited in close linkage with an infrequent HL-A typw, 2,4A2. The maternal, C2-defective chromosome was shown to be transmitted by HL-AW10, W18 haplotypemthis same haplotype was described in a similar study by Fu et al. (6) to be associated with C2 deficiencymfinally, a third haplotype HL-A2,W18 carrying a defective C2 gene was demonstrated in a part of this pedigree.


Asunto(s)
Complemento C2/deficiencia , Proteínas del Sistema Complemento/deficiencia , Antígenos HLA , Antígenos de Histocompatibilidad , Complemento C2/análisis , Femenino , Heterocigoto , Prueba de Histocompatibilidad , Homocigoto , Humanos , Lupus Eritematoso Sistémico/genética , Masculino , Linaje
8.
J Exp Med ; 153(1): 207-12, 1981 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-6969782

RESUMEN

We describe a new monoclonal murine antibody that reacts with a 50,000-mol wt polypeptide that appears to be present on all E-rosetting cells. We conclude that this antigen is either identical to or closely associated with the E receptor because of (a) the high degree of concordance between E-rosette formation and 9.6 antigen expression, (b) the inhibition of rosette formation by preincubation of cells with 9.6 antibody, and (c) the observed failure of cells lysostripped of 9.6 antigen to form E-rosettes. This last finding suggests cocapping of 9.6 antigen and the E receptor.


Asunto(s)
Receptores Inmunológicos/análisis , Formación de Roseta , Linfocitos T/inmunología , Antígenos de Superficie/análisis , Células Clonales/inmunología , Eritrocitos/inmunología , Humanos , Células Híbridas/inmunología , Isoanticuerpos , Proteínas de la Membrana/inmunología , Peso Molecular
9.
J Exp Med ; 159(2): 394-404, 1984 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-6420500

RESUMEN

Among DR4-associated HLA-D antigens, distinct and consistent structural variations were found for the products of two human "Ia-like" loci, DR and DS. Analysis of neuraminidase-treated immunoprecipitated DR molecules from 15 HLA-DR4-associated HLA-D homozygous B-lymphoblastoid cell lines by two dimensional polyacrylamide gel electrophoresis identified five distinct DR beta chains. In addition, gel analysis of immunoprecipitated DS molecules identified three distinct DS beta chains. Altogether, five distinct DR4 haplotypes were defined according to the observed structural diversity of the DR and DS beta chains. These gene products presumably contribute the dominant polymorphisms recognized by T cells in mixed lymphocyte reaction (MLR). Thus, these studies indicate that the serologic specificity known as HLA-DR4 is not a single haplotype, but a determinant present on products of individual loci arrayed into distinctly different haplotypes. These findings suggest that distinct products of individual loci, rather than conventional HLA specificities defined by alloimmune sera, may represent the genetic markers relevant to HLA-D/DR associated diseases.


Asunto(s)
Genes MHC Clase II , Haploidia , Anticuerpos Monoclonales/inmunología , Reacciones Antígeno-Anticuerpo , Fenómenos Químicos , Precipitación Química , Química , Variación Genética , Antígenos HLA-D , Antígenos HLA-DQ , Antígeno HLA-DR4 , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos
10.
J Exp Med ; 142(2): 495-506, 1975 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-124762

RESUMEN

Four families with C2 deficiency were studied. Among eight HL-A haplotypes involved with C2 deficiency, five were HL-A 10,W18. Three homozygotes for C2 deficiency from different families were mutually nonreactive in mixed lymphocyte cultures (MLC) and the heterozygotes from the fourth family failed to react to the homozygous cells. It appeared that identical MLC determinants were associated with all the genes from the different families that related to C2 deficiency. Further experiments identified the MLC determinant, LD-7a, as being involved. These results suggest marked linkage disequilibrium between the genes for C2 deficiency and the major histocompatibility complex (MHC). Studies of possible recombinants have offered tentative evidence for the positioning of the locus for C2 deficiency with respect to other segments of the MHC.


Asunto(s)
Complemento C2/deficiencia , Proteínas del Sistema Complemento/deficiencia , Ligamiento Genético , Antígenos HLA , Antígenos de Histocompatibilidad , Síndromes de Inmunodeficiencia/genética , Prueba de Cultivo Mixto de Linfocitos , Mapeo Cromosómico , Femenino , Heterocigoto , Prueba de Histocompatibilidad , Homocigoto , Humanos , Masculino , Linaje
11.
Waste Manag Res ; 28(5): 411-22, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19723830

RESUMEN

Improper management of pig manure has resulted in environmental problems such as surface water eutrophication, ground water pollution, and greenhouse gas emissions. This study develops and compares 14 alternative manure management scenarios aiming at energy and nutrient extraction. The scenarios based on combinations of thermal pretreatment, anaerobic digestion, anaerobic co-digestion, liquid/solid separation, drying, incineration, and thermal gasification were compared with respect to their energy, nutrient and greenhouse gas balances. Both sole pig manure and pig manure mixed with other types of waste materials were considered. Data for the analyses were obtained from existing waste treatment facilities, experimental plants, laboratory measurements and literature. The assessment reveals that incineration combined with liquid/solid separation and drying of the solids is a promising management option yielding a high potential energy utilization rate and greenhouse gas savings. If maximum electricity production is desired, anaerobic digestion is advantageous as the biogas can be converted to electricity at high efficiency in a gas engine while allowing production of heat for operation of the digestion process. In conclusion, this study shows that the choice of technology has a strong influence on energy, nutrient and greenhouse gas balances. Thus, to get the most reliable results, it is important to consider the most representative (and up-to-date) technology combined with data representing the area or region in question.


Asunto(s)
Dióxido de Carbono/análisis , Fuentes Generadoras de Energía , Estiércol/análisis , Nitrógeno/análisis , Fósforo/análisis , Porcinos , Administración de Residuos/métodos , Anaerobiosis , Animales , Suministros de Energía Eléctrica
12.
Tissue Antigens ; 74(6): 494-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19804563

RESUMEN

As part of the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), seven centers participated in a collaborative project to determine whether any significant humoral sensitization occurred post-transplant among recipients of HLA partially mismatched hematopoietic cell transplants (HCTs). A total of 140 donor/recipient pairs were enrolled with a total of 367 pre-and post-transplant sera analyzed. The majority of the samples (69.1%) were obtained within 30-90 days post-HCT. HLA-specific antibodies were defined using single antigen bead assays on a Luminex platform with a positive cutoff value of 1000 normalized median fluorescence intensity (MFI). There was an overall incidence of post-HCT sensitization toward donor HLA mismatches of 5.7%; however, all cases were among recipients of one HLA haplotype-mismatched grafts under nonmyeloablative, pre-transplant conditioning. Among the one haplotype-mismatched recipients, 15.7% (8/51) developed donor HLA-specific antibodies and 29.4% also had antibodies directed toward third party HLA antigens. Among the donor-specific antibodies, 9.8% were directed toward HLA class I antigens; 7.8% were against class II antigens; and 2.0% had both class I and II specificity. The relative strength of post-transplant antibodies was low with no significant difference in the mean maximum MFI values between third party and donor-specific antibodies. Because only a small number (10.2%) of the post-transplant samples were obtained 180 days or more post-HCT, longer term study is needed to evaluate any clinical relevance of these low-to-moderate levels of donor-specific antibody in one haplotype-mismatched recipients, as well as to determine whether any other antibodies occur at later times.


Asunto(s)
Antígenos HLA/inmunología , Trasplante de Células Madre Hematopoyéticas , Rechazo de Injerto/inmunología , Prueba de Histocompatibilidad , Humanos , Donantes de Tejidos
13.
Bone Marrow Transplant ; 53(7): 832-837, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29367715

RESUMEN

Biomarkers are increasingly used for diagnosis and treatment of transplant-related complications including the first biomarker-driven interventional trials of acute graft-versus-host disease (GvHD). In contrast, the development of biomarkers of chronic GvHD (cGvHD) has lagged behind due to a broader variety of manifestations, overlap with acute GvHD, a greater variation in time to onset and maximum severity, and lack of sufficient patient numbers within prospective trials. An international workshop organized by a North-American and European consortium was held in Marseille in March 2017 with the goal to discuss strategies for future biomarker development to guide cGvHD therapy. As a result of this meeting, two areas were prioritized: the development of prognostic biomarkers for subsequent onset of moderate/severe cGvHD, and in parallel, the development of qualified clinical-grade assays for biomarker quantification. The most promising prognostic serum biomarkers are CXCL9, ST2, matrix metalloproteinase-3, osteopontin, CXCL10, CXCL11, and CD163. Urine-proteomics and cellular subsets (CD4+ T-cell subsets, NK cell subsets, and CD19+CD21low B cells) represent additional potential prognostic biomarkers of cGvHD. A joint effort is required to verify the results of numerous exploratory trials before any of the potential candidates is ready for validation and subsequent clinical application.


Asunto(s)
Biomarcadores/metabolismo , Enfermedad Injerto contra Huésped/diagnóstico , Enfermedad Crónica , Femenino , Enfermedad Injerto contra Huésped/patología , Humanos , Masculino , Pronóstico
14.
J Clin Invest ; 52(12): 3064-73, 1973 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4201499

RESUMEN

B and T lymphocytes in 37 untreated patients with malignant lymphoma and Hodgkin's disease were studied. B cells in the peripheral blood were investigated with respect to surface immunoglobulins and in a few patients with respect to intracytoplasmic immunoglobulins by means of immunofluorescence. T cell function was studied by direct phytohemagglutinin (PHA) microtest (from the same sample of whole blood), mixed lymphocyte culture (MLC), and by delayed hypersensitivity to various antigens. In the 13 patients with Hodgkin's disease the histologic subtype was nodular sclerosis in nine, lymphocyte predominant in two, mixed cellularity in two. Only one of these patients had disseminated disease (stage IV); he showed impaired cellular immunity, a very low percentage of B cells and low levels of serum immunoglobulins. Of the remaining patients with Hodgkin's disease, with one exception, normal percentages but rather low absolute numbers of B lymphocytes per mm(3) of blood were found. One patient with a low percent and low absolute number of B lymphocytes showed very high serum IgG. Of 24 patients with non-Hodgkin's malignant lymphoma, seven (29%) showed monoclonal B cell proliferation in the peripheral blood (five mukappa, two gammakappa). By morphologic criteria, 14 patients had involvement of bone marrow, five of these had involvement of peripheral blood. Four of the latter five patients showed marked increases in percentages and absolute numbers of B lymphocytes in the peripheral blood reflecting the monoclonal proliferation. In three additional patients monoclonal proliferation of lymphocytes was found by immunofluorescence although the blood smears appeared morphologically normal. Serum immunoglobulin abnormalities without monoclonal B cell proliferation in the peripheral blood were observed in six patients.


Asunto(s)
Linfocitos B/inmunología , Enfermedad de Hodgkin/inmunología , Linfoma/inmunología , Adolescente , Adulto , Anciano , Membrana Celular/inmunología , Niño , Femenino , Técnica del Anticuerpo Fluorescente , Prueba de Histocompatibilidad , Enfermedad de Hodgkin/sangre , Humanos , Inmunoglobulinas/análisis , Lectinas , Activación de Linfocitos , Linfoma/sangre , Masculino , Persona de Mediana Edad , Pruebas Cutáneas , Linfocitos T/inmunología , Macroglobulinemia de Waldenström/inmunología
15.
J Clin Invest ; 77(4): 1224-32, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2420827

RESUMEN

We evaluated CD2 (E rosette) and CD3 (T3)-triggered activation of resting lymphocytes by measuring the intracellular free calcium concentration ([Ca2+]i) of individual cells. The [Ca2+]i of indo-1-loaded cells was measured by flow cytometry and responses were correlated with cell surface phenotype. Stimulation with anti-CD3 antibody caused an increase in [Ca2+]i in greater than 90% of CD3+ cells within 1 min, and furthermore, the response was restricted to cells bearing the CD3 marker. In contrast, stimulation of cells with anti-CD2 antibodies produced a biphasic response pattern with an early component in CD3- cells and a late component in CD3+ cells. Thus, the CD2 response does not require cell surface expression of CD3. In addition, stimulation of a single CD2 epitope was sufficient for activation of CD3- cells, whereas stimulation of two CD2 epitopes was required for activation of CD3+ cells. Both the CD2 and CD3 responses were diminished in magnitude and duration by EGTA. However, approximately 50% of T cells still had a brief response in the presence of EGTA, indicating that the increased [Ca2+]i results in part from intracellular calcium mobilization, and furthermore demonstrates that extracellular calcium is required for a full and sustained response. Our results support the concept that CD2 represents the trigger for a distinct pathway of activation both for T cells that express the CD3 molecular complex and for large granular lymphocytes that do not.


Asunto(s)
Antígenos de Superficie/farmacología , Calcio/metabolismo , Linfocitos/efectos de los fármacos , Anticuerpos Monoclonales , Antígenos de Diferenciación de Linfocitos T , Epítopos/inmunología , Citometría de Flujo , Humanos , Cinética , Receptores de Antígenos de Linfocitos T/metabolismo
16.
J Clin Invest ; 74(1): 287-91, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6610692

RESUMEN

The structural and functional heterogeneity of HLA-DR4-associated specificities was investigated in patients with seropositive juvenile rheumatoid arthritis, a DR4-associated disease. Using a combination of HLA-D analysis by mixed lymphocyte culture and electrophoretic analysis of immunoprecipitated Ia molecules by two-dimensional polyacrylamide gels, we observed a surprisingly homogeneous pattern of HLA-D antigen expression. All patients expressed common structural products of the DR and DS loci, and 7/12 homozygous DR4 patients expressed a rare and subtle HLA-D heterozygous phenotype.


Asunto(s)
Artritis Juvenil/inmunología , Antígenos de Histocompatibilidad Clase II/análisis , Linfocitos B/inmunología , Línea Celular , Niño , Tamización de Portadores Genéticos , Antígeno HLA-DR4 , Humanos , Sueros Inmunes , Fenotipo
17.
Curr Opin Immunol ; 11(5): 521-6, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10508715

RESUMEN

Hematopoietic cell transplantation from unrelated volunteer donors for the treatment of hematological malignancy can be optimized by complete and precise matching for HLA class I and II alleles between the donor and recipient. Survival is improved when the donor and recipient are matched for HLA-A, -B, -C, -DRB, -DQB1 and -DPB1 alleles. The risks of clinically severe graft-versus-host disease, graft failure and mortality are increased in the presence of multilocus mismatching. These findings demonstrate that HLA allelic differences are biologically relevant in human transplantation.


Asunto(s)
Rechazo de Injerto , Supervivencia de Injerto , Trasplante de Células Madre Hematopoyéticas , Prueba de Histocompatibilidad , Enfermedades Hematológicas/terapia , Humanos
18.
Curr Opin Immunol ; 13(5): 582-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11544008

RESUMEN

Unrelated-donor hematopoietic cell transplantation is a proven curative modality for hematologic malignancies. The success of unrelated-donor transplantation has been achieved through a better understanding of the immunobiology of the HLA system and through more precise and comprehensive matching of donors and recipients. The extensive polymorphism of HLA genes confers important biological implications affecting engraftment, graft-versus-host disease and overall survival. Although more-complete HLA identity of the donor and recipient is associated with optimal transplant outcome, new information suggests that not every HLA disparity is functionally relevant. Future advances in unrelated-donor transplantation must include the identification of tolerable HLA mismatches, so that more patients may benefit from this therapeutic modality. Furthermore, the role of cytokine-gene polymorphisms and minor histocompatibility genes in transplant outcome requires investigation. Delineation of the function of these markers as transplantation determinants may provide alternative means for optimizing the results of hematopoietic cell transplantation.


Asunto(s)
Genómica , Antígenos HLA/genética , Antígenos HLA/inmunología , Trasplante de Células Madre Hematopoyéticas/métodos , Prueba de Histocompatibilidad , Inmunología del Trasplante/genética , Animales , Humanos , Trasplante Homólogo
19.
Cancer Res ; 48(8): 2249-57, 1988 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-2964899

RESUMEN

Treatment of lymphoid malignancies with monoclonal antibodies (mAbs) and immunoconjugates is a promising new immunotherapeutic approach. However, few published studies have examined in detail the subcellular fate of antibodies following binding to lymphocyte cell surface antigens. In this study, we have investigated the disposition of monoclonal anti-CD3 antibody 64.1 following binding to normal and malignant T-lymphocytes by using cellular radioimmunoassays and immunoperoxidase and immunogold electron microscopy. Anti-CD3 mAbs were predominantly cleared from the cell membrane at 37 degrees C by receptor-mediated endocytosis, although passive shedding of antibody was also observed. Internalized antibody was sequentially transferred from coated pits to receptosomes and eventually to lysosomes. Intralysosomal degradation appeared to be the ultimate fate of internalized radiolabeled mAbs and was followed by exocytosis of free 125I to the culture medium. Ammonium chloride and monensin were potent inhibitors of lysosomal degradation of 125I-anti-CD3 mAbs and caused intracellular trapping of radiolabeled antibodies. The rapid endocytosis, degradation, and exocytosis of antibody observed in these studies elucidate the mechanism of the improved efficacy of anti-CD3 immunoconjugates when used in conjunction with inhibitors of lysosomal action.


Asunto(s)
Anticuerpos Monoclonales , Antígenos de Diferenciación de Linfocitos T/inmunología , Endocitosis , Linfocitos T/inmunología , Cloruro de Amonio/farmacología , Animales , Complejo CD3 , Oro , Humanos , Radioisótopos de Yodo , Ratones , Microscopía Electrónica , Monensina/farmacología , Linfocitos T/metabolismo , Transferrina/metabolismo , Células Tumorales Cultivadas/metabolismo
20.
Cancer Res ; 42(11): 4433-6, 1982 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7127284

RESUMEN

Protein carboxy-O-methyltransferase (PCM) activity was determined in subcellular fractions prepared from C-1300 neuroblastoma tumors following transplantation and growth in male A/J mice. Fractions were obtained by differential centrifugation, and PCM activity was determined in all fractions in the presence (+gel) and absence (-gel) of an exogenous substrate, gelatin. Sixty % of the PCM activity in the absence of exogenous substrate (-gel) was contained in the crude 800 X g particulate fraction, whereas 80% of the PCM activity in the presence of gelatin (+gel) was present in the postmicrosomal (100,000 X g) supernatant. The latter fraction also contained the highest specific activity of PCM. A Km of 3.2 X 10(-6) M and a Vmax of 5.3 pmol per mg protein per min were obtained for PCM activity (+gel) in the high-speed supernatant. Cytoplasmic PCM was highly sensitive to competitive inhibition by S-adenosylhomocysteine and the S-adenosyl-homocysteine analogs sinefungin and A-9145C with Ki values of 0.64, 0.47, and 0.05 microM, respectively. These data demonstrate that PCM present in murine neuroblastoma has characteristics similar to those of PCM isolated from other adrenergic and neuronal tissues. S-Adenosyl-homocysteine analogs may be useful probes for studying the role of PCM as a modulator of cell function in neurogenic and neoplastic tissues.


Asunto(s)
Neuroblastoma/enzimología , Proteína Metiltransferasas/metabolismo , Proteína O-Metiltransferasa/metabolismo , Animales , Línea Celular , Cinética , Masculino , Ratones , Ratones Endogámicos A , Neoplasias Experimentales/enzimología , Proteína O-Metiltransferasa/aislamiento & purificación , Fracciones Subcelulares/enzimología
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