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1.
Reprod Domest Anim ; 56(2): 270-277, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32920908

RESUMEN

Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms.


Asunto(s)
Genes sry/inmunología , Preselección del Sexo/veterinaria , Espermatozoides/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Bovinos , Femenino , Hibridomas , Masculino , Ratones Endogámicos BALB C , Preselección del Sexo/métodos , Bazo , Cromosoma Y/inmunología
2.
J Dairy Sci ; 94(4): 2060-70, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21426997

RESUMEN

This study was designed to identify sex-specific antibodies (SSAb) in rabbit antisera against bovine sex-sorted sperm, and capture sex-specific proteins of bovine X- or Y- proteins by SSAb. The rabbit antisera against bovine X- or Y-sperm were first produced by a series of immunological approaches, and further purified through immuno-neutralization with excess sex-sorted Y- or X-sperm, respectively, to remove non-sex specific antibodies and enrich sex-specific antibodies. After removal of non-sex specific antibodies, the purified rabbit sera with enriched sex-specific antibodies were screened for sex-specific antibodies by immunofluorescence staining and flow cytometry. The results showed that 3.0, 2.2, and 4.2% of unsorted sperm, sex-sorted X-sperm, and sex-sorted Y-sperm were recognized by the purified rabbit antisera against Y-sperm, respectively, whereas 29.2, 19.7, and 3.9% of unsorted sperm, sex-sorted X-sperm, and sex-sorted Y-sperm were recognized by the purified rabbit antisera against X-sperm. These results suggested that the purified rabbit antisera against X-sperm contained SSAb that preferentially bound to sex-sorted X-sperm. Subsequently, the purified rabbit antisera against X- or Y-sperm were used to immunoprecipitate sex-specific proteins in bovine sperm proteins, and a 30-kDa protein was specifically captured by the rabbit antisera against X-sperm. In conclusion, our results implied that this 30-kDa protein might be a sex-specific protein in bovine X-sperm, which has the potential to be used in immunological procedures for sexing sperm.


Asunto(s)
Proteínas de la Membrana/inmunología , Preselección del Sexo/veterinaria , Espermatozoides/inmunología , Cromosoma X/inmunología , Cromosoma Y/inmunología , Animales , Anticuerpos/análisis , Bovinos , Sueros Inmunes , Masculino , Proteínas de la Membrana/aislamiento & purificación , Conejos , Preselección del Sexo/métodos
3.
J Immunol ; 185(6): 3326-36, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20713889

RESUMEN

In humans and certain strains of laboratory mice, male tissue is recognized as nonself and destroyed by the female immune system via recognition of histocompatibility Y chromosome Ag (Hya). Male tissue destruction is thought to be accomplished by CTLs in a helper-dependent manner. We show that graft protection induced with the immunodominant Hya-encoded CD4 epitope (Dby) attached to female splenic leukocytes (Dby-SPs) with the chemical cross-linker ethylenecarbodiimide significantly, and often indefinitely, prolongs the survival of male skin graft transplants in an Ag-specific manner. In contrast, treatments with the Hya CD8 epitopes (Uty-/Smcy-SPs) failed to prolong graft survival. Dby-SP-tolerized CD4(+) T cells fail to proliferate, secrete IFN-gamma, or effectively prime a CD8 response in recipients of male grafts. Ag-coupled splenocyte treatment is associated with defective CD40-CD40L interactions as demonstrated by the observation that CD4 cells from treated animals exhibit a defect in CD40L upregulation following in vitro Ag challenge. Furthermore, treatment with an agonistic anti-CD40 Ab at the time of transplantation abrogates protection from graft rejection. Interestingly, anti-CD40 treatment completely restores the function of Dby-specific CD4 cells but not Uty- or Smcy-specific CD8 cells.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Ligando de CD40/antagonistas & inhibidores , Carbodiimidas/inmunología , Epítopos de Linfocito T/inmunología , Antígeno H-Y/inmunología , Bazo/inmunología , Regulación hacia Arriba/inmunología , Cromosoma Y/inmunología , Secuencia de Aminoácidos , Animales , Ligando de CD40/biosíntesis , Ligando de CD40/fisiología , Carbodiimidas/farmacología , Epítopos de Linfocito T/administración & dosificación , Femenino , Supervivencia de Injerto/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Epítopos Inmunodominantes/administración & dosificación , Epítopos Inmunodominantes/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Datos de Secuencia Molecular , Caracteres Sexuales , Bazo/citología , Bazo/trasplante
4.
Blood ; 108(4): 1413-20, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16638929

RESUMEN

Organ allografts have been shown to provide a syngeneic microenvironment for organ-based donor hematopoietic stem cells to maintain long-lasting chimerism after transplantation. We hypothesized that organ allografts would also support engraftment and hematopoiesis of adjunctively infused donor marrow stem cells, syngeneic to organ grafts, in nonmyeloablated recipients. In BN-to-LEW and GFP-to-ACI rat combinations, donor bone marrow (BM) infusion together with small intestine transplantation (SITx) under short-course tacrolimus immunosuppression resulted in persistent macrochimerism (more than 5%) for 150 days. In contrast, after BM infusion or SITx alone, chimerism was temporary and disappeared by day 100. Y-chromosome polymerase chain reaction (PCR) in sex-mismatched male BM plus female intestine or female BM plus male intestine transplantation into female recipients suggested that persistent macrochimerism was derived from infused BM. BM infusion together with lymphoid-depleted intestine grafts also supported macrochimerism development; however, third-party intestine grafts did not. After GFP-positive BM plus wild-type (WT) SITx into ACI, large numbers of GFP-positive leukocytes were found in WT intestine grafts. Isolated cells from WT intestine grafts developed GFP-positive CFU-Cs and propagated multilineage GFP-positive leukocytes when adoptively transferred into lethally irradiated WT recipients. These findings suggest that intestine allograft supports simultaneously infused donor (syngeneic to organ grafts) marrow stem cell engraftment, differentiation, and persistence of chimerism.


Asunto(s)
Trasplante de Médula Ósea , Supervivencia de Injerto , Intestino Delgado/trasplante , Trasplante Isogénico , Animales , Animales Modificados Genéticamente , Diferenciación Celular/inmunología , Femenino , Supervivencia de Injerto/efectos de los fármacos , Supervivencia de Injerto/inmunología , Terapia de Inmunosupresión , Inmunosupresores/farmacología , Intestino Delgado/inmunología , Leucocitos/inmunología , Depleción Linfocítica , Masculino , Ratas , Ratas Sprague-Dawley , Tacrolimus/farmacología , Factores de Tiempo , Quimera por Trasplante/inmunología , Cromosoma X/inmunología , Cromosoma Y/inmunología
5.
Arthritis Rheum ; 52(9): 2790-8, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16142734

RESUMEN

OBJECTIVE: Monocytosis is a unique cellular abnormality associated with the Yaa (Y-linked autoimmune acceleration) mutation. The present study was designed to define the cellular mechanism responsible for the development of monocytosis and to characterize the effect of the Yaa mutation on the development of monocyte subsets. METHODS: We produced bone marrow chimeras reconstituted with a mixture of Yaa and non-Yaa bone marrow cells bearing distinct Ly-17 alloantigens, and determined whether monocytes of Yaa origin became dominant. Moreover, we defined the 2 major inflammatory (Gr-1+,CD62 ligand [CD62L]+) and resident (Gr-1-,CD62L-) subsets of blood monocytes in aged BXSB Yaa male mice, as compared with BXSB male mice lacking the Yaa mutation. RESULTS: Analysis of the Ly17 allotype of blood monocytes in chimeric mice revealed that monocytes of both Yaa and non-Yaa origin were similarly involved in monocytosis. Significantly, the development of monocytosis paralleled a selective expansion of the resident monocyte subset compared with the inflammatory subset, and the former expressed CD11c, a marker of dendritic cells. Neither monocytosis nor the change in monocyte subpopulations, including CD11c expression, was observed in Yaa-bearing C57BL/6 mice, in which systemic lupus erythematosus (SLE) fails to develop. CONCLUSION: Our results suggest that Yaa-associated monocytosis is not attributable to an intrinsic abnormality in the growth potential of monocyte lineage cells bearing the Yaa mutation and that the Yaa mutation could lead to the expansion of dendritic cells, thereby contributing to the accelerated development of SLE.


Asunto(s)
Autoinmunidad/genética , Antígeno CD11c/metabolismo , Células Dendríticas/metabolismo , Lupus Eritematoso Sistémico/genética , Monocitos/citología , Cromosoma Y/genética , Animales , Anticuerpos Antinucleares/análisis , Biomarcadores , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/metabolismo , Proliferación Celular , Quimera , Modelos Animales de Enfermedad , Femenino , Leucocitosis , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/patología , Masculino , Ratones , Ratones Endogámicos NZB , Monocitos/inmunología , Monocitos/metabolismo , Cromosoma Y/inmunología
6.
Hematology ; 10(4): 289-95, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16085541

RESUMEN

OBJECTIVE: To study the immunogenicity of hematopoietic cells marked with green fluorescence protein (GFP) while avoiding the potentially confounding effects of viral gene transduction, marked cells from GFP+ transgenic mice were tracked after transplantation into unconditioned immunocompetent recipients. MATERIALS AND METHODS: Marrow was harvested from GFP+ transgenic mice that had been crossed onto a BALB/cByJ background. Unconditioned marrow transplantation involved infusion of sex-matched or sex-mismatched cells into female BALB/cByJ hosts. Engraftment and contribution to circulating nucleated blood cells were compared to recipients of donor cells that were not GFP-marked. Donor cells were detected by flow cytometry (GFP) and fluorescence in situ hybridization (FISH) for Y-chromosome sequences. RESULTS: Donor cells from mice of the same genetic background that did not express GFP were detected for more than four-weeks in unconditioned recipients. In contrast, GFP-marked cells in the blood peaked at one-week, declined to undetectable levels by two-weeks and were not detected in the marrow at sacrifice. In sex-mismatched studies, detection of male GFP+ donor cells by FISH yielded levels similar to those observed by flow cytometry, in contrast to the levels detected for many weeks in mice infused with male cells that did not express GFP. In immunocompetent recipients immunized with irradiated GFP-expressing cells, rechallenge with GFP+ cells resulted in the accelerated loss of donor cells. CONCLUSION: Donor marrow cells from GFP+ transgenic mice were lost after infusion into unconditioned immunocompetent mice and sensitization studies infer an immunologic mechanism. These results are similar to studies of virally transduced cells. Thus, infusion of cells with optimum engraftment potential could not compensate for the loss of donor cells due to immunogenicity.


Asunto(s)
Células Sanguíneas/inmunología , Trasplante de Médula Ósea , Rechazo de Injerto/inmunología , Proteínas Fluorescentes Verdes/inmunología , Transgenes/inmunología , Animales , Femenino , Citometría de Flujo , Supervivencia de Injerto/inmunología , Proteínas Fluorescentes Verdes/genética , Hibridación Fluorescente in Situ/métodos , Masculino , Ratones , Ratones Transgénicos , Transgenes/genética , Cromosoma Y/genética , Cromosoma Y/inmunología
7.
J Immunol ; 174(2): 1111-7, 2005 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-15634937

RESUMEN

By assessing the development of Y-linked autoimmune acceleration (Yaa) gene-induced systemic lupus erythematosus in C57BL/6 (B6) x (New Zealand Black (NZB) x B6.Yaa)F(1) backcross male mice, we mapped three major susceptibility loci derived from the NZB strain. These three quantitative trait loci (QTL) on NZB chromosomes 1, 7, and 13 differentially regulated three different autoimmune traits: anti-nuclear autoantibody production, gp70-anti-gp70 immune complex (gp70 IC) formation, and glomerulonephritis. Contributions to the disease traits were further confirmed by generating and analyzing three different B6.Yaa congenic mice, each carrying one individual NZB QTL. The chromosome 1 locus that overlapped with the previously identified Nba2 (NZB autoimmunity 2) locus regulated all three traits. A newly identified chromosome 7 locus, designated Nba5, selectively promoted anti-gp70 autoantibody production, hence the formation of gp70 IC and glomerulonephritis. B6.Yaa mice bearing the NZB chromosome 13 locus displayed increased serum gp70 production, but not gp70 IC formation and glomerulonephritis. This locus, called Sgp3 (serum gp70 production 3), selectively regulated the production of serum gp70, thereby contributing to the formation of nephritogenic gp70 IC and glomerulonephritis, in combination with Nba2 and Nba5 in NZB mice. Among these three loci, a major role of Nba2 was demonstrated, because B6.Yaa Nba2 congenic male mice developed the most severe disease. Finally, our analysis revealed the presence in B6 mice of an H2-linked QTL, which regulated autoantibody production. This locus had no apparent individual effect, but most likely modulated disease severity through interaction with NZB-derived susceptibility loci.


Asunto(s)
Ligamiento Genético/inmunología , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , Ratones Endogámicos NZB/genética , Sitios de Carácter Cuantitativo/inmunología , Cromosoma Y/inmunología , Animales , Anticuerpos Antinucleares/sangre , Complejo Antígeno-Anticuerpo/sangre , Autoantígenos/sangre , Cromatina/inmunología , Cruzamientos Genéticos , Marcadores Genéticos/inmunología , Predisposición Genética a la Enfermedad , Glomerulonefritis/genética , Glomerulonefritis/inmunología , Glicoproteínas/sangre , Glicoproteínas/genética , Inmunoglobulina G/sangre , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/inmunología , Masculino , Ratones , Ratones Congénicos , Ratones Endogámicos C57BL , Chaperonas Moleculares/genética , Mutación , Síndrome , Regulación hacia Arriba/genética , Regulación hacia Arriba/inmunología
8.
J Immunol ; 173(7): 4724-8, 2004 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-15383609

RESUMEN

Rheumatoid factors (RF) are autoantibodies with specificity for the Fc portion of IgG, and IgG-containing immune complexes are likely to be the major source of RF autoantigens. Therefore, the activation of RF-producing B cells could be controlled specifically through recognition of IgG immune complexes by the low-affinity IgG FcR, FcgammaRIIB, a potent negative regulator of the BCR. To test this possibility, we determined the development of RF in C57BL/6 (B6) mice lacking FcgammaRIIB, in relation to the H2 haplotype, complement C3, and the Y-linked autoimmune acceleration (Yaa) mutation. FcgammaRIIB-null B6 mice displayed substantial anti-IgG2a RF activities in their sera, in addition to anti-DNA autoantibodies. Their RF and anti-DNA responses were linked to the H2(b) haplotype, but were suppressed almost completely by the H2(d) haplotype. Strikingly, the absence of C3 failed to modulate RF production, but strongly inhibited anti-DNA production. Furthermore, we observed that partial FcgammaRIIB deficiency (i.e., heterozygous level of FcgammaRIIB expression) was sufficient to induce the production of RF and anti-DNA autoantibodies in the presence of the Yaa mutation. In contrast to FcgammaRIIB, the deficiency in another BCR negative regulator, CD22, was unable to promote RF and anti-DNA autoimmune responses in B6 mice. Our results indicate that RF autoimmune responses are critically controlled by FcgammaRIIB, together with the H2(b) and Yaa gene, while C3 regulates positively and specifically anti-DNA, but not RF autoimmune responses.


Asunto(s)
Antígenos CD/fisiología , Receptores de IgG/fisiología , Factor Reumatoide/biosíntesis , Animales , Anticuerpos Antinucleares/biosíntesis , Anticuerpos Antinucleares/sangre , Antígenos CD/genética , Antígenos de Diferenciación de Linfocitos B/genética , Moléculas de Adhesión Celular/deficiencia , Moléculas de Adhesión Celular/genética , Células Cultivadas , Complemento C3/deficiencia , Complemento C3/genética , ADN/inmunología , Femenino , Ligamiento Genético/inmunología , Antígenos H-2/fisiología , Terapia de Inmunosupresión/métodos , Lectinas/deficiencia , Lectinas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Receptores de IgG/deficiencia , Receptores de IgG/genética , Lectina 2 Similar a Ig de Unión al Ácido Siálico , Bazo/citología , Bazo/inmunología , Bazo/metabolismo , Cromosoma Y/genética , Cromosoma Y/inmunología
9.
J Immunol ; 170(5): 2293-301, 2003 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-12594250

RESUMEN

The accelerated development of systemic lupus erythematosus (SLE) in BXSB male mice is associated with the presence of an as yet unidentified mutant gene, Yaa (Y-linked autoimmune acceleration). In view of a possible role of marginal zone (MZ) B cells in murine SLE, we have explored whether the expression of the Yaa mutation affects the differentiation of MZ and follicular B cells, thereby implicating the acceleration of the disease. In this study, we show that both BXSB and C57BL/6 Yaa mice, including two different substrains of BXSB Yaa males that are protected from SLE, displayed an impaired development of MZ B cells early in life. Studies in bone marrow chimeras revealed that the loss of MZ B cells resulted from a defect intrinsic to B cells expressing the Yaa mutation. The lack of selective expansion of MZ B cells in diseased BXSB Yaa males strongly argues against a major role of MZ B cells in the generation of pathogenic autoantibodies in the BXSB model of SLE. Furthermore, a comparative analysis with mice deficient in CD22 or expressing an IgM anti-trinitrophenyl/DNA transgene suggests that the hyperreactive phenotype of Yaa B cells, as judged by a markedly increased spontaneous IgM secretion, is likely to contribute to the enhanced maturation toward follicular B cells and the block in the MZ B cell generation.


Asunto(s)
Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/patología , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , Mutación , Cromosoma Y/genética , Cromosoma Y/inmunología , Animales , Antígenos T-Independientes/administración & dosificación , Antígenos T-Independientes/inmunología , Subgrupos de Linfocitos B/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Células Cultivadas , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Regulación de la Expresión Génica/inmunología , Inmunoglobulina M/biosíntesis , Inmunoglobulina M/genética , Inyecciones Intravenosas , Factores de Transcripción de Tipo Kruppel , Nefritis Lúpica/patología , Recuento de Linfocitos , Linfopenia/genética , Linfopenia/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Mutantes , Ratones Transgénicos , Receptores de Complemento 3d/biosíntesis , Bazo/inmunología , Bazo/metabolismo , Bazo/patología , Células Madre/inmunología , Células Madre/patología , Factores de Transcripción/biosíntesis , Factores de Transcripción/deficiencia , Factores de Transcripción/genética , Transgenes/inmunología , Trinitrobencenos/inmunología
10.
Clin Immunol ; 103(3 Pt 1): 303-8, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12173305

RESUMEN

Recent studies have demonstrated the presence of microchimeric cells in peripheral blood and skin lesions from patients with systemic sclerosis (SSc). In a previous study we found that some peripheral blood CD3+ cells from female patients with SSc contained male DNA. Here, peripheral blood samples from 47 patients with SSc (30 with diffuse cutaneous SSc and 17 with limited cutaneous SSc) and 22 healthy controls were sorted for CD4+ and CD8+ T cells. Both positively and negatively selected populations were analyzed for male DNA by quantitative PCR. Analysis of Y chromosome sequences in the sorted cells demonstrated the presence of microchimerism in 82.9% of SSc patients compared to 63.6% of controls. The numbers of CD4+ and CD8+ T cells were found to be significantly higher in the SSc patients than in controls. Furthermore, patients with dcSSc were observed to have significantly more CD4+ microchimeric T cells than the controls. In the CD8+ T-cell population, there was a trend toward more microchimeric cells in the patients but this did not reach significance. These results support the hypothesis that microchimeric CD4+ T cells may be involved in the pathogenesis of SSc.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , ADN/genética , Esclerodermia Sistémica/inmunología , Cromosoma Y/inmunología , ADN/inmunología , Femenino , Humanos , Separación Inmunomagnética , Masculino , Reacción en Cadena de la Polimerasa , Esclerodermia Sistémica/sangre , Esclerodermia Sistémica/genética , Análisis de Secuencia de ADN , Subgrupos de Linfocitos T/inmunología , Cromosoma Y/genética
11.
J Reprod Immunol ; 52(1-2): 77-84, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11600179

RESUMEN

Recent studies have established that there is bi-directional cell traffic between mother and fetus during pregnancy. Suprisingly, fetal cells have been found to persist in the maternal circulation for years after pregnancy. Maternal cells can also persist into adult life in her progeny. When cells from one individual are present in the body of another the term chimerism is used and a low level of non-host cells is referred to as microchimerism. Chronic graft-versus-host disease often occurs after stem cell transplantation, is a known condition of chimerism, and resembles spontaneously occurring autoimmune diseases including systemic sclerosis, Sjögren's syndrome, primary biliary cirrhosis and sometimes myositis and systemic lupus. Of central importance to the development of chronic graft-versus-host disease is the HLA relationship of host and donor cells. Considering this constellation of observations together led to the hypothesis that microchimerism and HLA-relationships are involved in the pathogenesis of some autoimmune diseases. Although much additional work is needed, results of initial studies provide support to the concept that non-host cells could participate in the pathogenesis of some autoimmune diseases.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Antígenos HLA/inmunología , Embarazo/inmunología , Esclerodermia Sistémica/inmunología , Quimera/inmunología , Femenino , Histocompatibilidad/inmunología , Prueba de Histocompatibilidad , Humanos , Masculino , Estudios Prospectivos , Cromosoma Y/inmunología
13.
J Immunol ; 166(7): 4429-37, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11254698

RESUMEN

Whether intrathymic-positive and -negative selection of conventional alpha beta T cells occur in anatomically distinct sites is a matter of debate. By using a system composed of two distinct immune receptors, the Y-Ae mAb and the 1H3.1 (V alpha 1/V beta 6) TCR, both directed against the 52--68 fragment of the I-E alpha-chain (E alpha 52--68) bound to I-A(b), we examined the occurrence of negative selection imposed in vivo by a self-peptide-self-MHC class II complex with differential tissue expression. 1H3.1 TCR-transgenic (Tg) mice were bred to mice having an I-E alpha transgene with expression directed to all MHC class II-positive cells, restricted to thymic epithelial cells, or restricted to B cells, dendritic cells, and medullary thymic epithelial cells. All 1H3.1 TCR/I-E alpha double-Tg mice revealed a severely diminished thymic cellularity. Their lymph node cells were depleted of V beta 6(+)CD4(+) cells and were unresponsive to E alpha 52--68 in vitro. The absolute number of CD4(+)CD8(+) thymocytes was drastically reduced in all combinations, indicating that negative selection caused by an endogenously expressed self-determinant can effectively occur in the thymic cortex in vivo. Moreover, both cortical epithelial cells and, interestingly, the few cortical dendritic cells were able to support negative selection of CD4(+)CD8(+) thymocytes, albeit with a distinct efficiency. Collectively, these observations support a model where, in addition to the avidity of the thymocyte/stromal cell interaction, in vivo negative selection of autoreactive TCR-Tg T cells is determined by accessibility to self-peptide-self-MHC complexes regardless of the anatomical site.


Asunto(s)
Antígenos de Histocompatibilidad Clase II/inmunología , Fragmentos de Péptidos , Péptidos/inmunología , Péptidos/metabolismo , Receptores de Antígenos de Linfocitos T , Autotolerancia , Subgrupos de Linfocitos T/metabolismo , Timo/citología , Timo/inmunología , Animales , Antígenos de Superficie/biosíntesis , Antígenos de Superficie/genética , Antígenos de Superficie/inmunología , Autoantígenos/genética , Autoantígenos/inmunología , Autoantígenos/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Supresión Clonal/genética , Cruzamientos Genéticos , Epítopos de Linfocito T/genética , Antígenos de Histocompatibilidad Clase II/genética , Sustancias Macromoleculares , Masculino , Ratones , Ratones Endogámicos A , Ratones Endogámicos AKR , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Péptidos/genética , Receptores de Antígenos de Linfocitos T alfa-beta/biosíntesis , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Autotolerancia/genética , Subgrupos de Linfocitos T/inmunología , Timo/metabolismo , Cromosoma Y/genética , Cromosoma Y/inmunología
14.
Actas dermo-sifiliogr. (Ed. impr.) ; 91(11): 487-497, nov. 2000. ilus, tab
Artículo en Es | IBECS | ID: ibc-3976

RESUMEN

Durante el embarazo se produce una transferencia de células desde el feto hacia la madre y viceversa. Algunas son células progenitoras hematopoyéticas capaces de persistir viables durante décadas, dando lugar a microquimerismos. Estos microquimerismos pueden estar implicados en la etiopatogenia de ciertas enfermedades, como la esclerosis sistémica. Mediante nested PCR para amplificar secuencias de ADN del gen SRY, específico del cromosoma Y, realizamos un estudio prospectivo a fin de investigar la presencia de microquimerismos fetales en 25 muestras de sangre, piel afecta y piel sana de 10 pacientes afectas de morfea que habían tenido uno o más hijos y/o abortos de sexo masculino o desconocido. La sensibilidad de la técnica fue del 0,01-0,004%. Se detectaron secuencias SRY en tres pacientes (dos muestras de sangre periférica, una de piel afecta y una de piel sana perilesional). Los resultados fueron negativos en las 30 muestras procedentes de 16 pacientes control, 11 de ellas potencialmente expuestas a microquimerismos masculinos durante la gestación. Estos hallazgos sugieren que los microquimerismos fetales podrían estar implicados en la etiopatogenia de la morfea. Sin embargo, su detección en piel aparentemente sana parece indicar que no son suficientes para el desarrollo de la enfermedad (AU)


Asunto(s)
Adulto , Embarazo , Femenino , Humanos , Quimera/inmunología , Complicaciones del Embarazo/diagnóstico , Esclerodermia Localizada/etiología , Estudios Prospectivos , Sensibilidad y Especificidad , Cromosoma Y/inmunología , Complicaciones del Embarazo/inmunología , Reacción en Cadena de la Polimerasa , Esclerodermia Localizada/diagnóstico
15.
J Immunol ; 165(6): 2987-96, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10975807

RESUMEN

The Cd22 gene encodes a B cell-specific adhesion molecule that modulates B cell Ag receptor-mediated signal transduction, and is allelic to a lupus-susceptibility locus in New Zealand White (NZW) mice. In this study, we show that, in addition to the wild-type transcripts, NZW (Cd22a) mice synthesize aberrant CD22 mRNAs that contain approximately 20-120 nucleotide insertions upstream of the coding region between exons 2 and 3, and/or approximately 100-190 nucleotide deletions of exon 4. Sequence analysis revealed that these aberrant mRNA species arose by alternative splicing due to the presence in the NZW strain of a 794-bp sequence insertion in the second intron, containing a cluster of short interspersed nucleotide elements. Both the presence of sequence insertion and aberrantly spliced mRNAs were specific to mice bearing the Cd22a and Cd22c alleles. Up-regulation of CD22 expression after LPS activation appeared impaired in Cd22a spleen cells (twice lower than in Cd22b B cells). Furthermore, we show that partial CD22 deficiency, i.e., heterozygous level of CD22 expression, markedly promotes the production of IgG anti-DNA autoantibodies in C57BL/6 (Cd22b) mice bearing the Y chromosome-linked autoimmune acceleration gene, Yaa. Taken together, these results suggest that a lower up-regulation of CD22 on activated B cells (resulting from Cd22 gene anomaly in Cd22a mice or from CD22 heterozygosity in mutants obtained by gene targeting) is implicated in autoantibody production, providing support for Cd22a as a possible candidate allele contributing to lupus susceptibility.


Asunto(s)
Antígenos CD/genética , Antígenos de Diferenciación de Linfocitos B/genética , Moléculas de Adhesión Celular , Regulación de la Expresión Génica/inmunología , Lectinas , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , Mutagénesis Insercional/inmunología , Elementos de Nucleótido Esparcido Corto/inmunología , Regiones no Traducidas 5'/biosíntesis , Regiones no Traducidas 5'/genética , Empalme Alternativo/inmunología , Animales , Antígenos CD/biosíntesis , Antígenos de Diferenciación de Linfocitos B/biosíntesis , Linfocitos B/inmunología , Linfocitos B/metabolismo , Secuencia de Bases , Exones , Síndromes de Inmunodeficiencia/genética , Intrones , Lipopolisacáridos/inmunología , Activación de Linfocitos/genética , Masculino , Ratones , Ratones Endogámicos AKR , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Endogámicos DBA , Ratones Endogámicos MRL lpr , Ratones Endogámicos NZB , Ratones Mutantes , Datos de Secuencia Molecular , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN Mensajero/biosíntesis , Eliminación de Secuencia , Lectina 2 Similar a Ig de Unión al Ácido Siálico , Bazo/citología , Regulación hacia Arriba/inmunología , Cromosoma Y/inmunología
16.
J Immunol ; 164(11): 5545-8, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10820227

RESUMEN

The host's MHC genotype plays a critical role in susceptibility to autoimmune diseases. We previously proposed that persistent fetal microchimerism from pregnancy contributes to the pathogenesis of autoimmune diseases such as scleroderma. In the current study, we investigated whether the specific host MHC genotype is associated with persistent microchimerism among T lymphocytes in women with scleroderma and in healthy women. Fetal microchimerism among T lymphocytes was strongly associated with HLA DQA1*0501 of the mother (odds ratio (OR) = 13.5, p = 0.007, p corrected (pc) = 0.06) and even more strongly with DQA1*0501 of the son (OR = infinity; p = 0. 00002, pc = 0.0002). This is the first description of an association between persistent fetal microchimerism in maternal T lymphocytes and specific HLA class II alleles. Although the association was observed in both healthy women and in women with scleroderma, the finding suggests an additional route by which HLA genes might contribute to susceptibility to autoimmune disease.


Asunto(s)
Enfermedades Autoinmunes/genética , Quimera/inmunología , Feto/inmunología , Antígenos HLA-DQ/genética , Subgrupos de Linfocitos T/inmunología , Adolescente , Adulto , Anciano , Alelos , Niño , Preescolar , Femenino , Antígenos HLA-DQ/biosíntesis , Cadenas alfa de HLA-DQ , Humanos , Lactante , Masculino , Persona de Mediana Edad , Embarazo , Esclerodermia Sistémica/genética , Esclerodermia Sistémica/inmunología , Subgrupos de Linfocitos T/metabolismo , Cromosoma Y/inmunología
17.
Cell Immunol ; 200(2): 76-80, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10753498

RESUMEN

Murine acquired immunodeficiency syndrome (MAIDS) is characterized by lymphoproliferation, polyclonal B cell activation resulting in the production of autoantibodies, and a progressive immunodeficiency. These are all hallmarks of some autoimmune diseases. Yaa is a Y-chromosome-linked gene that accelerates autoimmune diseases in some autoimmune-prone strains of mice. To further elucidate a possible relationship with autoimmunity, the effect of the Yaa gene on MAIDS was investigated. Analysis of phenotypic and functional disease parameters revealed that Yaa does not accelerate MAIDS disease. This is probably due to the generalized activation of most or all lymphoid cells in MAIDS, which cannot be enhanced by the Yaa gene. This result is in accordance with the selective enhancing effect of the Yaa gene on the immune response against self and foreign antigens in a specific genetic background. It suggests that the autoimmune response associated with MAIDS is a secondary phenomenon. Interestingly, even in wild-type C57BL/6 mice, autoantibody production may contribute overproportionally to the hypergammaglobulinemia associated with MAIDS.


Asunto(s)
Autoinmunidad/genética , Síndrome de Inmunodeficiencia Adquirida del Murino/inmunología , Mutación , Cromosoma Y/inmunología , Animales , Anticuerpos Antinucleares/inmunología , Linfocitos B/inmunología , Línea Celular , Células Cultivadas , ADN de Cadena Simple/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Síndrome de Inmunodeficiencia Adquirida del Murino/genética , Síndrome de Inmunodeficiencia Adquirida del Murino/fisiopatología , Bazo/citología , Antígenos Thy-1/inmunología
18.
J Immunol ; 164(5): 2807-14, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10679124

RESUMEN

The mammalian Y chromosome encodes male-specific minor histocompatibility (H-Y) Ags that are recognized by female T cells in an MHC-restricted manner. Two human H-Y epitopes presented by HLA-A2 and HLA-B7, respectively, have been identified previously and both are derived from the SMCY gene. We previously isolated CD8+ CTL clones that recognized a male-specific minor histocompatibility Ag presented by HLA-B8. In contrast to the SMCY-encoded H-Y epitopes, the B8/H-Y Ag was not presented by fibroblasts from male donors, suggesting that it was encoded by a novel gene. We now report that the HLA-B8-restricted H-Y epitope is defined by the octameric peptide LPHNHTDL corresponding to aa residues 566-573 of the human UTY protein. Transcription of the UTY gene is detected in a wide range of human tissues, but presentation of the UTY-derived H-Y epitope to CTL by cultured human cells shows significant cell-type specificity. Identification of this CTL-defined H-Y epitope should facilitate analysis of its contribution to graft/host interactions following sex-mismatched organ and bone marrow transplantation.


Asunto(s)
Antígeno H-Y/genética , Antígeno HLA-B8/genética , Proteínas/genética , Secuencia de Aminoácidos , Animales , Células COS , Línea Celular Transformada , Células Cultivadas , Mapeo Cromosómico , Epítopos/biosíntesis , Epítopos/genética , Femenino , Regulación de la Expresión Génica/inmunología , Antígeno H-Y/biosíntesis , Antígeno HLA-B8/biosíntesis , Humanos , Masculino , Antígenos de Histocompatibilidad Menor , Datos de Secuencia Molecular , Proteínas Nucleares , Oligopéptidos/genética , Oligopéptidos/inmunología , Oligopéptidos/aislamiento & purificación , Especificidad de Órganos/genética , Especificidad de Órganos/inmunología , Biosíntesis de Proteínas , Proteínas/inmunología , Cromosoma Y/inmunología
19.
Arch Pathol Lab Med ; 122(8): 708-14, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9701332

RESUMEN

BACKGROUND: Posttransplant lymphoproliferative disorders in bone marrow transplantation are typically rapidly progressive and fatal B-cell lymphoid proliferations associated with Epstein-Barr virus, and are mostly of donor origin. We report three pediatric bone marrow transplant cases in which posttransplant lymphoproliferative disorder was diagnosed at postmortem examination. Epstein-Barr virus in these cases was identified by a combined in situ hybridization-immunoperoxidase technique and donor origin was identified by fluorescence in situ hybridization. METHODS: Tissues obtained from postmortem examination were evaluated by light microscopy, immunohistochemistry, combined in situ hybridization-immunoperoxidase technique with Epstein-Barr virus-encoded RNA probe, and fluorescence in situ hybridization with X and Y centromeric probes. RESULTS: Three pediatric patients underwent sex-mismatched, T-cell-depleted bone marrow transplants complicated by graft versus host disease, rapidly progressive multiple organ failure, and postmortem diagnosis of posttransplant lymphoproliferative disorder. Histologic examination and immunohistochemistry studies demonstrated immunoblastic lymphoma (one case) or polymorphic B-cell lymphoma (two cases). In all cases, Epstein-Barr virus-encoded RNA was detected by a combined in situ hybridization-immunoperoxidase technique. Fluorescence in situ hybridization for X and Y chromosomes in paraffin sections demonstrated donor origin in two cases (one case was indeterminate). CONCLUSION: Fluorescence in situ hybridization was used to prove donor derivation of Epstein-Barr virus-associated posttransplant lymphoproliferative disorders in pediatric bone marrow transplant recipients. Many features of posttransplant lymphoproliferative disorders in pediatric bone marrow transplant recipients are very similar to adult cases, although a higher proportion of children appear to be diagnosed postmortem and have a fatal outcome.


Asunto(s)
Trasplante de Médula Ósea , Trastornos Linfoproliferativos/inmunología , Trastornos Linfoproliferativos/virología , Niño , Preescolar , Resultado Fatal , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/inmunología , Humanos , Hibridación Fluorescente in Situ , Lactante , Trastornos Linfoproliferativos/genética , Masculino , ARN Viral/análisis , Donantes de Tejidos , Proteínas de la Matriz Viral/análisis , Cromosoma X/inmunología , Cromosoma Y/inmunología
20.
J Reprod Fertil ; 110(2): 195-204, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9306971

RESUMEN

Currently, the only successful method for separating X and Y chromosome-bearing spermatozoa is fluorescence-activated cell sorting. Although effective, this technique is of limited usefulness to the animal breeding industry as it cannot produce the large volumes of sexed spermatozoa needed for artificial insemination. An attractive alternative would be to identify an immunological marker confined to one sperm type and, therefore, significant scientific effort has been expended in examining antibodies that appear to recognize approximately 50% of spermatozoa in an ejaculate. However, no sex-specific antigens have yet been identified from spermatozoa. Using the opportunity afforded by the development of sperm separation by fluorescence-activated cell sorting, we have made a thorough search for differences between X and Y chromosome-bearing bull spermatozoa using both biochemical and immunological methods. Techniques for radiolabelling surface membrane proteins, in conjunction with SDS-PAGE, failed to show any differences between populations. Similarly, a wide range of monoclonal antibodies raised to ejaculated, cauda epididymidal and testicular spermatozoa failed to distinguish between the X and Y chromosome-bearing spermatozoa. Only after analysis by high resolution two-dimensional SDS-PAGE was an indication obtained that X-specific proteins occur. However, these proteins are not associated with the surface membrane and further work is necessary to confirm their association with the X chromosome and to characterize them more fully. Our inability to detect sex-specific differences in sperm surface antigenicity suggests that further work on this immunological approach to semen sexing is unlikely to be profitable.


Asunto(s)
Antígenos de Superficie/análisis , Bovinos/genética , Espermatozoides/inmunología , Cromosoma X/inmunología , Cromosoma Y/inmunología , Animales , Anticuerpos Monoclonales , Autorradiografía , Western Blotting , Bovinos/inmunología , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Citometría de Flujo , Radioisótopos de Yodo , Masculino , Unión Proteica , Tinción con Nitrato de Plata
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