RESUMEN
Transfer of CD45RB(high) CD4+ T cells to immune-deficient mice in the absence of regulatory T cells leads to a Th1-mediated colitis. In this study, we show that intestinal inflammation is characterized by a 15-fold increase in the number of CD134L+ (OX40L+)-activated DC in the mesenteric lymph nodes (MLNs) compared with BALB/c mice. This was important functionally, as administration of an anti-CD134L mAb inhibited the proliferation of T cells in the MLNs as well as their expression of the gut-homing integrin alpha(4)beta(7). Most importantly, the anti-CD134L mAb completely blocked development of colitis. Surprisingly, CD134L was found to be expressed by a proportion of dendritic cells (DC) in the MLNs of unreconstituted SCID mice, suggesting that CD134L can be induced on DC in the absence of T cell-derived signals. These results indicate that some DC in the MLNs of SCID mice express an activated phenotype and that CD134L expression by these cells is involved in the development of colitis induced by T cell transfer. Accumulation of CD134L+ DC was inhibited by cotransfer of regulatory T cells, suggesting that inhibition of the accumulation of activated DC is one mechanism by which these cells prevent immune pathology.
Asunto(s)
Colitis/inmunología , Células Dendríticas/inmunología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Glicoproteínas de Membrana , Receptores del Factor de Necrosis Tumoral/biosíntesis , Linfocitos T/trasplante , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/biosíntesis , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Animales , Anticuerpos Bloqueadores/administración & dosificación , Anticuerpos Bloqueadores/biosíntesis , Anticuerpos Bloqueadores/genética , Anticuerpos Bloqueadores/farmacología , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/farmacología , Recuento de Células , Colitis/genética , Colitis/patología , Colitis/prevención & control , Células Dendríticas/metabolismo , Células Dendríticas/patología , Inhibidores de Crecimiento/administración & dosificación , Inhibidores de Crecimiento/farmacología , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacología , Inyecciones Intraperitoneales , Ligandos , Ganglios Linfáticos/patología , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Transfusión de Linfocitos , Mesenterio , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ratones SCID , Ligando OX40 , Ratas , Receptores OX40 , Receptores del Factor de Necrosis Tumoral/metabolismo , Linfocitos T/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Factores de Necrosis Tumoral , Síndrome Debilitante/genética , Síndrome Debilitante/inmunología , Síndrome Debilitante/prevención & controlRESUMEN
OX2 (CD200) is a type-1 membrane glycoprotein that contains two immunoglobulin superfamily domains and which is expressed on a variety of lymphoid and non-lymphoid cells in the rat. The recent characterization of a receptor for OX2 (OX2R) on myeloid cells, and the phenotype of an OX2-deficient mouse, suggests that OX2 may regulate myeloid cell activity in anatomically diverse locations. Here we report the tissue distribution of the human homologue of the rat OX2 glycoprotein using a new monoclonal antibody (mAb), OX104, raised against recombinant human OX2. Human OX2 was expressed at the cell surface of thymocytes, B cells, T cells, neurons, kidney glomeruli, tonsil follicles, the syncytiotrophoblast and endothelial cells. This broad, but not ubiquitous, distribution pattern is very similar to that observed in rats, suggesting that OX2 may regulate myeloid cell activity in a variety of tissues in humans.
Asunto(s)
Antígenos de Superficie/metabolismo , Tejido Linfoide/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD , Antígenos de Superficie/inmunología , Cerebelo/metabolismo , Secuencia Conservada , Humanos , Técnicas para Inmunoenzimas , Masculino , Ratones , Ratones Endogámicos BALB C , Nervios Periféricos/metabolismo , Especificidad de la Especie , Timo/metabolismo , Distribución TisularRESUMEN
Monoclonal antibodies have proven to be powerful tools for studying the properties of leukocyte surface antigens and the cells that express them. In the past decades many monoclonal antibodies (mAb) for identifying the different rat leukocyte surface antigens have been described. A list of mAb is provided in Table I below. The rat leukocyte surface antigens are divided into different sections, including rat CD antigens (a), rat leukocyte surface antigens without CD designation (b), rat major histocompatibility complex (MHC) antigens (c), rat T-cell receptors (d) and rat immunoglobulins (e). The molecular and functional characteristics of rat leukocyte surface antigens are discussed in more detail in some of the other chapters of this issue (e.g. Van den Berg et al., p. 45). A more extensive overview of the properties of leukocyte surface antigens is provided by Barclay et al.
Asunto(s)
Anticuerpos Monoclonales , Antígenos de Superficie/inmunología , Leucocitos/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Humanos , RatasRESUMEN
The CD nomenclature used for human-leukocyte surface antigens is now being widely applied to naming their homologs in other species. This appendix catalogs those CD antigens that have been clearly defined in the rat. There are also many other antigens defined in the rat, but only those for which good biochemical data are available, such as amino acid sequences, are given here. The most commonly used antibodies are summarized.
Asunto(s)
Anticuerpos Monoclonales/clasificación , Antígenos CD/clasificación , Antígenos de Histocompatibilidad/clasificación , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD/inmunología , Antígenos de Histocompatibilidad/inmunología , Humanos , Ratas , Especificidad de la EspecieRESUMEN
The OX2 membrane glycoprotein (CD200) is expressed on a broad range of tissues including lymphoid cells, neurons, and endothelium. We report the characterization of an OX2 receptor (OX2R) that is a novel protein restricted to cells of the myeloid lineage. OX2 and its receptor are both cell surface glycoproteins containing two immunoglobulin-like domains and interact with a dissociation constant of 2.5 microM and koff 0.8 s(-1), typical of many leukocyte protein membrane interactions. Pervanandate treatment of macrophages showed that OX2R could be phosphorylated on tyrosine residues. Blockade of the OX2-OX2R interaction with an OX2R mAb exacerbated the disease model experimental allergic encephalomyelitis. These data, together with data from an OX2-deficient mouse (R. M. Hoek et al., submitted), suggest that myeloid function can be controlled in a tissue-specific manner by the OX2-OX2R interaction.
Asunto(s)
Leucopoyesis/fisiología , Macrófagos/fisiología , Receptores Inmunológicos/fisiología , Secuencia de Aminoácidos , Animales , Clonación Molecular , Inmunoglobulinas/fisiología , Linfocitos/fisiología , Ratones , Datos de Secuencia Molecular , Neuronas/fisiología , Ratas , Alineación de Secuencia , Transducción de Señal/fisiologíaRESUMEN
The present article describes procedures to measure rat IL-4 protein. The RT-PCR technique has been successfully and widely used to measure IL-4 mRNA, but it does not determine IL-4 protein synthesis. Assays to measure rat IL-4 protein based on its biological activity were developed using the mAb OX-81, which inhibits rat IL-4 activity. Two bioassays were attempted based on the ability of IL-4 to induce the proliferation of T cell blasts and to increase MHC class II expression on resting B cells. A second mAb against rat IL-4 was used in a sandwich ELISA to detect rat IL-4. This ELISA is satisfactory although its sensitivity is not as high as that of the bioassay. According to our experience, the bioassay based on the induction of class II MHC molecules on B cells is the technique of choice for rat IL-4 determination because it proved specific, sensitive and reproducible.
Asunto(s)
Interleucina-4/análisis , Animales , Anticuerpos Monoclonales , Concanavalina A/farmacología , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Antígenos de Histocompatibilidad Clase II/biosíntesis , Interleucina-4/farmacología , Activación de Linfocitos/efectos de los fármacos , Masculino , Ratones , Ratas , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismoRESUMEN
CD4 is the primary receptor for human immunodeficiency virus (HIV). The binding site for the surface glycoprotein of HIV type 1 (HIV-1), gp120, has been mapped to the C'-C" region of domain 1 of CD4. Previously, we have shown that a mutant of rat CD4, in which this region was exchanged for that of human CD4, is able to mediate infection of human cells by HIV-1, suggesting that essential interactions between HIV and CD4 are confined to this region. Our observations appeared to conflict with mutagenesis and antibody studies which implicate regions of CD4 outside the gp120-binding site in postbinding events during viral entry. In order to resolve this issue, we have utilized a panel of anti-rat CD4 monoclonal antibodies in conjunction with the rat-human chimeric CD4 to distinguish sequence-specific from steric effects. We find that several antibodies to rat CD4 inhibit HIV infection in cells expressing the chimeric CD4 and that this is probably due to steric hinderance. In addition, we demonstrate that replacement of the rat CDR3-like region with its human homolog does not increase the affinity of the rat-human chimeric CD4 for gp120 or affect the exposure of gp41 following binding to CD4, providing further evidence that this region does not play a crucial role during entry of virus.
Asunto(s)
Antígenos CD4/inmunología , Epítopos/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/virología , VIH-1/fisiología , Replicación Viral/inmunología , Secuencia de Aminoácidos , Animales , Mapeo Epitopo , Humanos , Ratones , Datos de Secuencia Molecular , RatasRESUMEN
The contributions of blood vessels in various transplantation paradigms of solid CNS tissue or cell suspension allografts placed into adult host brains were investigated immunohistochemically using the PVG-RT1C and PVG-RT1U inbred rat strains and a panel of highly specific monoclonal antibodies. The monoclonal antibodies included OX-27 and U9F4 against major histocompatibility complex (MHC) class I antigens of the PVG-RT1C and PVG-RT1U rats, respectively; OX-26 against the rat transferrin receptor located on blood-brain barrier (BBB) endothelia; and OX-7 against rat neuronal Thy 1.1 for evaluating graft survival. Our study is the first to address the immunogenicity of blood vessels in surviving CNS allografts. Solid fetal or neonatal PVG-RT1C cortex was grafted into the third or lateral cerebral ventricle or caudate/putamen of PVG-RT1U adult hosts for 30 days to 7 months. All allografts expressed demonstrable Thy 1.1 immunoreactivity with OX-7 antibody and appeared well-vascularized with blood vessels that immunostained with the OX-26 antibody against the transferrin receptor. For the most part, the allografts were supplied sparsely with donor (PVG-RT1C) MHC class I-positive (OX-27) blood vessels clustered in pockets. Donor MHC class I-positive vessels entered the host brain only from allografts in the third ventricle; these vessels were restricted to the host median eminence and no longer immunostained with OX-26 for the transferrin receptor (normally the median eminence is supplied with non-BBB vessels that do not possess the transferrin receptor and do not stain with OX-26). In host brains harboring a third ventricle allograft, host MHC class I-positive vessels immunostained with the U9F4 antibody were evident throughout the host CNS, including the median eminence, and throughout the allografts excluding sites inhabited by donor PVG-RT1C vessels. Cell suspension neural allografts (donor PVG-RT1C) placed within the brain parenchyma of PVG-RT1U hosts revealed no significant differences in vascular contributions between donor and host when compared to results obtained from solid CNS allografts. A unique immunohistochemical approach of introducing ascites fluid OX-27 as the primary antibody intravenously to the PVG-RT1U host demonstrated that in donor PVG-RT1C posterior pituitary allografts, donor and not host vessels predominate and are restricted to the graft. Finally, blood vessels isolated from adult PVG-RT1C brains were mixed with solid fetal PVG-RT1U cortical tissue and grafted into the brain parenchyma of adult PVG-RT1U hosts. Immunostaining with OX-27 antibody against MHC class I of the PVG-RT1C rat strain disclosed that the PVG-RT1C blood vessels survived and were confined to the PVG-RT1U syngeneic graft. The results suggest that blood vessels supplying CNS allografts placed within the host brain are predominantly of host origin; surviving donor vessels are restricted to the allograft with rare exceptions, which may be dictated by the type of neural allograft and the host CNS site receiving the allograft. The survival of isolated allogeneic CNS blood vessels grafted into the host brain suggests that such blood vessels can present an endothelial genotype and phenotype different from those of host vessels indigenous to the CNS site receiving the allogeneic vessel graft. This finding may have implications in the circumvention of the blood-brain fluid barriers for the CNS delivery of blood-borne therapeutics.
Asunto(s)
Arterias Cerebrales/trasplante , Corteza Cerebral/trasplante , Trasplante de Tejido Fetal , Neurohipófisis/trasplante , Factores de Edad , Animales , Anticuerpos Monoclonales , Materiales Biocompatibles , Química Encefálica , Corteza Cerebral/irrigación sanguínea , Femenino , Supervivencia de Injerto , Enfermedad Injerto contra Huésped , Antígenos de Histocompatibilidad Clase I/análisis , Antígenos de Histocompatibilidad Clase I/inmunología , Masculino , Ratas , Ratas Endogámicas , Receptores de Transferrina/análisis , Receptores de Transferrina/inmunología , Trasplante HomólogoRESUMEN
OX40, a member of the tumor necrosis factor (TNF) receptor/nerve growth factor (NGF) receptor superfamily was first identified as a marker of activated rat CD4+ cells with the MRC OX40 monoclonal antibody (mAb). A ligand for OX40 (called OX40 ligand or OX40L) has recently been identified and has sequence similarity to TNF. Mouse OX40L-immunoglobulin fusion protein (OX40L-Ig) binds to activated mouse CD4+ and CD8+ cells (Baum, P. R. et al., EMBO J. 1994. 13: 3992) suggesting that OX40 could have a differential pattern of expression on mouse and rat T cells. This, however, did not rule out the presence of an alternative receptor on CD8+ cells that also binds the OX40L. We have compared the binding of the MRC OX40 mAb with that of OX40L-Ig to activated rat lymph node cells and show that both recognize the same protein, namely OX40 which is expressed on CD4+ and CD4+ CD8 alpha+ cells, but not on CD4-CD8+ cells. We have raised a new mAb (MRC OX86) using recombinant mouse OX40 protein and show by two-color flow cytometry that mouse OX40 is expressed on CD4 and CD8 single-positive cells. In addition, the new MRC OX86 mAb, unlike the MRC OX40 mAb, did not block binding of the OX40L. We conclude that OX40 is differentially expressed on activated mouse and rat T cells and is the sole receptor for the OX40L.
Asunto(s)
Activación de Linfocitos , Glicoproteínas de Membrana , Receptores del Factor de Necrosis Tumoral/metabolismo , Linfocitos T/metabolismo , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/biosíntesis , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Animales , Anticuerpos Monoclonales/química , Células CHO , Cricetinae , Ratones , Ratones Endogámicos BALB C , Ligando OX40 , Ratas , Ratas Endogámicas , Receptores OX40 , Receptores del Factor de Necrosis Tumoral/inmunología , Proteínas Recombinantes/genética , Linfocitos T/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Factores de Necrosis TumoralRESUMEN
Purified rat CD4+ T cells were activated in vitro in the presence or absence of the glucocorticoid dexamethasone. They were then expanded in IL-2 and subsequently restimulated, this time in the absence of the hormone. The results indicate that the exposure of the cells to dexamethasone in the primary stimulation changed the cytokine synthesis induced by the secondary stimulation. The mRNA levels for IL-4, IL-10, and IL-13 were all increased by the pretreatment, whereas synthesis of IFN-gamma and TNF-alpha was diminished. Further studies in which IL-4 was used together with dexamethasone showed that the cytokine potentiated the effect of the hormone. These data suggest that the neuroendocrine system can influence the cytokine response to pathogens and autoantigens in a way that favors Th2-type reactions. There are similar implications for therapy with glucocorticoids, and these drugs may be expected to have long term immunologic effects as well as short-lived immunosuppressive ones. The production of a mouse mAb, MRC-OX81, against rat IL-4 is also described.
Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Citocinas/biosíntesis , Dexametasona/farmacología , Glucocorticoides/farmacología , Células Th2/efectos de los fármacos , Células Th2/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Secuencia de Bases , Concanavalina A/farmacología , Citocinas/genética , Cartilla de ADN/genética , Técnicas In Vitro , Interferón gamma/biosíntesis , Interferón gamma/genética , Interleucina-10/biosíntesis , Interleucina-10/genética , Interleucina-13/biosíntesis , Interleucina-13/genética , Interleucina-4/biosíntesis , Interleucina-4/genética , Activación de Linfocitos , Ratones , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Células TH1/efectos de los fármacos , Células TH1/inmunología , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/genéticaAsunto(s)
Antígenos de Diferenciación de Linfocitos T/biosíntesis , Glicoproteínas/biosíntesis , Receptores Inmunológicos/biosíntesis , Proteínas Recombinantes de Fusión/biosíntesis , Animales , Antígenos de Diferenciación de Linfocitos T/genética , Antígenos CD2 , Células CHO/metabolismo , Secuencia de Carbohidratos , Cricetinae , Cricetulus , Glicoproteínas/genética , Glicosilación , Humanos , Lactante , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Conformación Proteica , Procesamiento Proteico-Postraduccional , Receptores Inmunológicos/genética , Solubilidad , Linfocitos TRESUMEN
A mouse immunoglobulin G1 monoclonal antibody (mAb), MRC OX-62 (OX-62), was raised against density gradient-enriched rat veiled (dendritic) cells obtained from lymph. In suspensions of lymphoid cells, the OX-62 mAb only labeled cells with the characteristics of veiled cells. The OX-62 mAb was used with a magnetic cell sorter to enrich or deplete veiled cells, and the enriched veiled cells were potent stimulators in the primary allogeneic mixed leukocyte reaction. Immunohistochemical staining of tissue sections showed that the OX-62 mAb did not label all classical dendritic cells and was not restricted to this cell type. In lymphoid tissues, the labeling correlated with dendritic cells, but in skin, major histocompatibility complex class II+ cells were OX-62-, while another CD3+ cell with dendritic morphology was strongly OX-62+. It seems that the OX-62 mAb may be restricted to dendritic cells and probably to gamma/delta T cells. The OX-62 mAb will be of use in delineating minor subsets of cells with dendritic morphology in various tissues. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of veiled cell-enriched populations immunoprecipitated with the OX-62 mAb gave bands with the biochemical characteristics of an integrin. The OX-62 mAb recognized the alpha-like subunit.
Asunto(s)
Antígenos de Superficie/análisis , Células Dendríticas/citología , Integrinas/análisis , Leucocitos/citología , Linfocitos/citología , Animales , Anticuerpos Monoclonales , Antígenos CD , Biomarcadores , Separación Celular/métodos , Citometría de Flujo/métodos , Hibridación Genética , Hibridomas/inmunología , Inmunohistoquímica , Magnetismo , Glicoproteínas de Membrana/análisis , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Especificidad de Órganos , Ratas , Ratas EndogámicasRESUMEN
Immunization protocols that induce high levels of delayed-type hypersensitivity are often associated with low levels of antibody production, whereas alternative immunization strategies can produce the opposite effect. This reciprocal relationship appears to depend, at least in part, on the fact that T cell-derived lymphokines that are predominantly involved in one type of response inhibit the development of those T cells that promote the alternative one. Such a regulatory mechanism is likely to be bistable in that whenever one form of response is established, spontaneous development of the alternative one will be inhibited. We have applied this concept to the control of a cell-mediated autoimmune disease in rats. By covalently linking the autoantigen to anti-IgD antibody, we have targeted it to B cells for presentation to antigen-specific T cells. This form of presentation favors antibody production and may be expected to antagonize the cell-mediated disease-inducing response to the same antigen. To test this hypothesis, use was made of the fact that experimental allergic encephalomyelitis (EAE), when induced with the encephalitogenic peptide of guinea pig myelin basic protein, is purely a cell-mediated disease. The experiments show that Lewis rats, immunized with the peptide in its encephalitogenic form, were protected from disease when simultaneously injected with the peptide coupled to anti-IgD monoclonal antibodies. Control experiments showed that neither peptide nor anti-IgD alone were protective, and the peptide covalently coupled to irrelevant antibodies also failed to protect. Spleen cells from animals protected from disease by the anti-IgD-peptide conjugate, when activated in vitro with the encephalitogen, were able to transfer EAE to naive recipients. The results demonstrate that a cell-mediated immune response can be controlled by appropriate targeting of the specific antigen without inducing T cell anergy and suggest a potential strategy for preventing autoimmune diseases that are essentially cell-mediated in type.
Asunto(s)
Autoantígenos/inmunología , Enfermedades Autoinmunes/prevención & control , Linfocitos B/inmunología , Inmunidad Celular/inmunología , Animales , Anticuerpos Antiidiotipos , Células Presentadoras de Antígenos/inmunología , Enfermedades Autoinmunes/inmunología , Encefalomielitis Autoinmune Experimental/etiología , Femenino , Inmunoglobulina D/inmunología , Masculino , Proteínas de la Mielina/inmunología , Ratas , Ratas Endogámicas LewRESUMEN
The CD4 cell surface antigen is of interest as a marker of T lymphocytes that recognize foreign antigens in the context of MHC Class II antigen, as a receptor for the human immunodeficiency virus (HIV) and as a member of the immunoglobulin superfamily (IgSF) with four Ig-like domains present in the extracellular domain. In order to produce large amounts of soluble CD4 for x-ray crystallography and other molecular studies, a recently developed expression system based on selection via glutamine synthetase was used. Expression was attempted for rat CD4 corresponding to the full extracellular sequence (sCD4; domains 1-4), the NH2-terminal half (domains 1 and 2) and the first domain alone. Stable transfected Chinese hamster ovary cell lines were obtained that expressed sCD4 and sCD4 (half) at typical maximal levels in spent tissue culture supernatant of greater than 80 and 25 mg/liter, respectively. Domain 1 alone was not expressed and introduction of a N-linked glycosylation site did not facilitate expression. The role of glycosylation in the expression of sCD4 was investigated by mutagenesis of the constructs to remove each of the two N-linked glycosylation sites in turn and both together. All three forms were expressed at 60-120 mg/liter. The sCD4 (half) was not expressed after deletion of its N-linked site. The disulfide bonds of sCD4 were determined to be within domains 1, 2, and 4 and isolation of glycopeptides showed that both N-linked sites were glycosylated. Analysis of the hydrodynamic properties of sCD4 suggested that the molecule adopted an extended conformation in solution rather than folding to form a compact structure like an Fab. The possibility of dimerisation of CD4 was investigated but sCD4 dimers were not seen at an affinity cut-off of about 4 x 10(5) M-1.
Asunto(s)
Antígenos CD4/genética , Expresión Génica , Variación Genética , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Antígenos CD4/inmunología , Antígenos CD4/aislamiento & purificación , Línea Celular , Cricetinae , Cricetulus , Femenino , Genes MHC Clase II , Glicopéptidos/aislamiento & purificación , Glicosilación , Datos de Secuencia Molecular , Ovario , Fragmentos de Péptidos/aislamiento & purificación , Ratas , TransfecciónAsunto(s)
Trasplante de Tejido Encefálico/inmunología , Núcleo Caudado , Corteza Cerebral/trasplante , Ventrículos Cerebrales , Supervivencia de Injerto , Ratas Endogámicas/inmunología , Animales , Antígenos de Diferenciación , Antígenos de Superficie/inmunología , Corteza Cerebral/inmunología , Supervivencia de Injerto/inmunología , Antígenos de Histocompatibilidad/inmunología , Especificidad de Órganos , Ratas , Antígenos Thy-1 , Trasplante HomólogoRESUMEN
In this report we detail a procedure for the cloning of a rat encephalitogenic T cell line and show that the methods normally employed for other species may not always be applicable. The two important differences to be described are, (i) that in these experiments where the parent T cell lines were generated with thymocytes as presenting cells, splenocytes were not suitable as a source of antigen-presenting or stimulator cells and (ii) semipurified forms of IL-2, specifically that derived from EL4 lymphoma cells, resulted in a much reduced cloning frequency and rate of T cell growth compared with cruder mixtures such as that derived from mitogen-stimulated splenocytes. Functional studies with clones derived from a strongly encephalitogenic (experimental autoimmune encephalomyelitis (EAE)-inducing) T cell line revealed that the clones had a reduced capacity to mediate EAE in recipient rats but were otherwise comparable to the parent line in terms of surface phenotype and fine antigen specificity. In an attempt to begin to identify the type of CD4+ T cells that may induce EAE we tested the clones and lines for secreted interferon-gamma by a sensitive ELISA, and showed that all clones secreted high levels of this factor.
Asunto(s)
Antígenos de Diferenciación de Linfocitos T/análisis , Encefalomielitis Autoinmune Experimental/etiología , Interferón gamma/metabolismo , Linfocitos T/inmunología , Animales , Línea Celular , Células Clonales , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Masculino , Proteína Básica de Mielina/inmunología , Ratas , Ratas Endogámicas Lew , Bazo/inmunologíaRESUMEN
Rat T cells and thymocytes were induced to proliferate by a pair of mAbs, MRC OX-54 and MRC OX-55, directed against rat CD2. Accessory cells were required but their role was not simply for crosslinking of the two mAbs, as neither MRC OX-54 nor MRC OX-55 alone, in the presence of a crosslinking second antibody, caused T cell mitogenesis. Nor could the phorbol ester PMA replace either antibody. The two mAbs recognized distinct epitopes on rat CD2; however, MRC OX-54 could partially block MRC OX-55 binding whereas the reverse situation was not seen. A further CD2 epitope was recognized by two mutually competitive mAbs, MRC OX-34 and MRC OX-53, which were not mitogenic. Neither MRC OX-34 nor MRC OX-53 affected the binding of MRC OX-54 or MRC OX-55, yet they prevented the mitogenic effect induced by these mAbs. The presence of mAbs against CD4 and the IL-2-R also abrogated this mitogenesis, whereas an anti-CD5 mAb augmented the CD2-induced proliferation.
Asunto(s)
Antígenos de Diferenciación de Linfocitos T/inmunología , Activación de Linfocitos , Linfocitos T/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Reacciones Antígeno-Anticuerpo , Células Presentadoras de Antígenos/inmunología , Células Cultivadas , Relación Dosis-Respuesta Inmunológica , Ganglios Linfáticos/inmunología , Activación de Linfocitos/efectos de los fármacos , Ratas , Receptores Inmunológicos/inmunología , Receptores de Interleucina-2 , Acetato de Tetradecanoilforbol/farmacologíaRESUMEN
Mouse monoclonal antibodies (MAbs) have been prepared against rat T cell blasts. One MAb called MRC OX-40 recognized an antigen that differed from any previously described in that its expression was detected only on T blasts that also expressed the CD4 antigen. The OX-40 MAb did not detect an activation determinant of CD2 or CD4 molecules but recognized a distinct chain of mol. wt 50,000. The OX-40 MAb augmented T cell proliferation at late stages on in vitro responses. Other MAbs without obvious counterparts in other species were MRC OX-48 and MRC OX-49,50 which recognized cell surface molecules of mol. wts of about 95,000 and 90,000, respectively. The OX-48 antigen was not expressed on resting lymphocytes but was found on a subset of T and B blasts and also on other leucocytes. The OX-49,50 antigen was found on most haemopoietic cells but was expressed at greatly increased levels after lymphocyte activation and this was also the case for MRC OX-47 antigen which is of unknown Mr. The MRC OX-39 MAb was found to bind the rat IL-2 receptor; expression of this antigen was detected on thymic dendritic cells as well as on T blasts. The phenotype of rat T blasts compared to resting cells was also examined and changes in expression of L-CA, Thy-1, OX-2 and CD8 antigens were seen in addition to the changes found with the above MAbs.
Asunto(s)
Antígenos de Superficie/análisis , Activación de Linfocitos , Linfocitos T/inmunología , Animales , Anticuerpos Monoclonales/inmunología , División Celular , Concanavalina A/farmacología , Electroforesis en Gel de Poliacrilamida , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Ratas , Ratas Endogámicas , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis TumoralRESUMEN
A monoclonal antibody called MRC OX-44 is described that labels all myeloid cells and peripheral lymphoid cells but only 12% of thymocytes. The OX-44+ thymic cells include most if not all cells found in the medulla but only a small fraction of the cortical cells. Together with CD4 and CD8 antigens, seven subsets of thymic cell were defined and it was notable that most CD4- CD8- cells were OX-44+ whereas almost all CD4+ CD8+ cells were OX-44-. In functional tests, the OX-44+ cells accounted for all proliferation by thymocytes when stimulated by allogeneic spleen cells or concanavalin A plus growth factors and OX-44- cells were completely negative in these assays. Also, in tests for thymopoiesis after intra-thymic injection of cells, all activity was OX-44+. It seems possible that the OX-44+ set may include all functionally relevant cells in the rat thymus.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Linfocitos T/clasificación , Timo/citología , Animales , Antígenos de Diferenciación de Linfocitos T , Antígenos de Superficie/análisis , Células Dendríticas/inmunología , Activación de Linfocitos , Linfocitos/clasificación , Linfocitos/citología , Linfocitos/inmunología , Peso Molecular , Monocitos/clasificación , Monocitos/citología , Monocitos/inmunología , Ratas , Regeneración , Linfocitos T/citología , Linfocitos T/inmunología , Timo/fisiologíaRESUMEN
Neural grafts from day 17-19 fetal rats or mice survived well when transplanted into syngeneic, or immunodeficient hosts, thus demonstrating that there are no non-immunological barriers to cross-species transplantation of neuronal tissue in rats and mice. However, intraventricular grafts from rat to mouse, or vice versa, in immunocompetent animals were rejected in less than 30 days. By this time all graft tissue had been destroyed and scavenged, presumably by the macrophages seen infiltrating the grafts within 10 days of grafting. Rat allografts from major histocompatibility complex disparate donors disparate donors survived well as did grafts between rats differing only at minor histocompatibility loci. However, allografts from donors that differed from recipients at both major and minor histocompatibility complex loci had a variable survival time. When neural tissue was grafted into immunologically primed recipients, it was rejected as was similar tissue grafted beneath the kidney capsule of an allogeneic host. Concomitant grafting of allogeneic tissue under the kidney capsule and into the third ventricle was followed by rejection in both sites. A striking observation in these studies was the induction of Class I major histocompatibility complex antigens on grafted neuronal tissue. High levels of antigen expression were correlated with a vigorous host response and poor graft survival but lower levels were not indicative of impending graft destruction. Whilst the brain can be regarded as an immunologically privileged site, the privilege is not absolute and caution needs to be exercised in the interpretation of results from allogeneic or xenogeneic grafts.