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1.
J Autoimmun ; 147: 103246, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38788540

RESUMEN

OBJECTIVES: Systemic sclerosis (SSc) is a multiorgan disease with a 10-year mortality rate of up to 50 %. B cell-depleting therapy with rituximab (RTX) appears effective in SSc treatment, but data from randomized controlled trials (RCTs) are lacking, and the frequency and dosage of RTX in SSc have no consensus. We aimed to evaluate the long-term efficacy and safety of quarterly RTX administration in SSc. METHODS: This study retrospectively analyzed 40 patients with SSC treated with RTX twice within 14 days every 3 months from 2010 to 2020. The patients fulfilled the LeRoy and the American College of Rheumatology/European League Against Rheumatism Criteria for SSc. Modified Rodnan skin score (mRSS), lung function test results, and serum immunoglobulin (IgG, IgA, and IgM) concentrations were analyzed. RESULTS: A total of 40 patients with SSc received RTX over a median time of 3.9 years (range: 1-10 years). The median mRSS (baseline: 19, 24 months: 16, p < 0.001) demonstrated a significant improvement, and the predicted forced vital capacity was stable. No new or unexpected safety signals, especially regarding treatment-related infectious adverse events, were observed. Immunoglobulin concentrations were within normal range, and specific antibodies to pneumococcal polysaccharides were preserved despite long-term B cell-depleting therapy. None of the patients died during the observation period of up to 10 years. CONCLUSION: SSc was effectively and safely treated with low-dose RTX quarterly. RCTs are warranted to validate the advantage of continuous B cell depletion by quarterly low-dose RTX administration compared to other treatment intervals.


Asunto(s)
Linfocitos B , Depleción Linfocítica , Rituximab , Esclerodermia Sistémica , Humanos , Esclerodermia Sistémica/mortalidad , Esclerodermia Sistémica/inmunología , Esclerodermia Sistémica/terapia , Esclerodermia Sistémica/tratamiento farmacológico , Femenino , Masculino , Persona de Mediana Edad , Linfocitos B/inmunología , Rituximab/uso terapéutico , Estudios Retrospectivos , Adulto , Resultado del Tratamiento , Anciano
2.
Clin Exp Rheumatol ; 32(5 Suppl 85): S-55-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25365090

RESUMEN

Providing the physician with sufficient information about the disease course can be regarded as the most important requirement for any disease assessment tool besides easy applicability and time-sparing documentation. Applying the RADAI-5 in daily routine provides the patient's view at any time completing the questionnaire. In a first study, the RADAI-5 resulted to be highly significantly correlated to the RADAI, and all composite indexes. Changes of the RADAI-5, the DAS28-ESR, and the CDAI were significantly correlated, indicating the instrument's sensitivity to change. A second study including 392 RA patients led to the establishment of thresholds for disease activity categories according to the RADAI-5, as follows: 0.0 up to 1.4 for a remission-like state, 1.6 up to 3.0 for mild disease activity, 3.2 up to 5.4 for moderate and from 5.6 up to 10.0 for high disease activity. In a third study, remission according to the RADAI-5 appeared to be highly specific for the ACR/EULAR criteria for remission The RADAI-5 questionnaire constitutes an easily applicable tool for routine RA monitoring, providing physicians with reliable information about the disease course and sensitivity enough to sound the alarm should complications occur.


Asunto(s)
Artritis Reumatoide/diagnóstico , Indicadores de Salud , Articulaciones , Reumatología/métodos , Encuestas y Cuestionarios , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/fisiopatología , Sedimentación Sanguínea , Progresión de la Enfermedad , Estado de Salud , Humanos , Articulaciones/efectos de los fármacos , Articulaciones/patología , Articulaciones/fisiopatología , Valor Predictivo de las Pruebas , Inducción de Remisión , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento
3.
Clin Exp Rheumatol ; 28(6): 888-91, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21205465

RESUMEN

OBJECTIVES: Sera from patients with lymphoid neoplasias contain rheumatoid factors (RF) so often that RF are of limited use for diagnosing arthritis in lymphoma patients. Antibodies against citrullinated peptides (ACPA) might be helpful in distinguishing between true RA and rheumatoid factor-positive conditions with arthritis. We compared the specificity of RF and of ACPA for the diagnosis of RA in patients with B-cell chronic lymphocytic leukemia (CLL). METHODS: One hundred and seven patients with CLL without any clinical signs of arthritis and five patients with RA and concomitant CLL were included in the investigation. Serum samples were tested for RF-isotypes IgM, IgG and IgA. ACPA were determined with an ELISA that detects anti-cyclic citrullinated peptide (aCCP) antibodies. RESULTS: RF well beyond the cut-off levels were detected in 50% of the CLL patients without RA. The isotype distribution was 41% IgM-RF, 20% IgG-RF and 3% IgA-RF. None of the 107 CLL patients without arthritis had Accp antibodies. Within the whole cohort of CLL patients the specificity for the diagnosis of RA was 100% for aCCP antibodies and 59% for IgM-RF. CONCLUSIONS: Only aCCP antibodies but not IgM-, IgG- or IgA-RF are useful for the diagnosis of RA in patients with CLL.


Asunto(s)
Anticuerpos Antiidiotipos/sangre , Especificidad de Anticuerpos , Artritis Reumatoide/diagnóstico , Leucemia Linfocítica Crónica de Células B/complicaciones , Péptidos Cíclicos/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antiidiotipos/inmunología , Artritis Reumatoide/sangre , Artritis Reumatoide/inmunología , Estudios de Casos y Controles , Femenino , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/inmunología , Masculino , Persona de Mediana Edad , Factor Reumatoide/inmunología , Sensibilidad y Especificidad
4.
Ann Rheum Dis ; 68(6): 805-11, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19015206

RESUMEN

BACKGROUND: Tumour necrosis factor alpha (TNFalpha) is a proinflammatory cytokine involved in the pathogenesis of rheumatoid arthritis (RA). Treatment with TNFalpha inhibitors reduces disease activity and improves outcomes for patients with RA. This study evaluated the efficacy and safety of certolizumab pegol 400 mg, a novel, poly-(ethylene glycol) (PEG)ylated, Fc-free TNFalpha inhibitor, as monotherapy in patients with active RA. METHODS: In this 24-week, multicentre, randomised, double-blind, placebo-controlled study, 220 patients previously failing > or =1 disease-modifying antirheumatic drug (DMARD) were randomised 1:1 to receive subcutaneous certolizumab pegol 400 mg (n = 111) or placebo (n = 109) every 4 weeks. The primary endpoint was 20% improvement according to the American College of Rheumatology criteria (ACR20) at week 24. Secondary endpoints included ACR50/70 response, ACR component scores, 28-joint Disease Activity Score Erythrocyte Sedimentation Rate 3 (DAS28(ESR)3), patient-reported outcomes (including physical function, health-related quality of life (HRQoL), pain and fatigue) and safety. RESULTS: At week 24, the ACR20 response rates were 45.5% for certolizumab pegol 400 mg every 4 weeks vs 9.3% for placebo (p<0.001). Differences for certolizumab pegol vs placebo in the ACR20 response were statistically significant as early as week 1 through to week 24 (p<0.001). Significant improvements in ACR50, ACR components, DAS28(ESR)3 and all patient-reported outcomes were also observed early with certolizumab pegol and were sustained throughout the study. Most adverse events were mild or moderate and no deaths or cases of tuberculosis were reported. CONCLUSIONS: Treatment with certolizumab pegol 400 mg monotherapy every 4 weeks effectively reduced the signs and symptoms of active RA in patients previously failing > or =1 DMARD compared with placebo, and demonstrated an acceptable safety profile. TRIAL REGISTRATION NUMBER: NCT00548834.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Fragmentos Fab de Inmunoglobulinas/administración & dosificación , Inmunosupresores/administración & dosificación , Polietilenglicoles/administración & dosificación , Adulto , Análisis de Varianza , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Artritis Reumatoide/inmunología , Certolizumab Pegol , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Inmunosupresores/uso terapéutico , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Tamaño de la Muestra , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
6.
J Clin Invest ; 99(7): 1614-27, 1997 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9120005

RESUMEN

To analyze the human kappa chain repertoire and the influences that shape it, a single cell PCR technique was used that amplified Vkappa Jkappa rearrangements from genomic DNA of individual human B cells. More than 350 productive and 250 nonproductive Vkappa Jkappa rearrangements were sequenced. Nearly every functional Vkappa gene segment was used in rearrangements, although six Vkappa gene segments, A27, L2, L6, L12a, A17, and O12/O2 were used preferentially. Of these, A27, L2, L6, and L12a showed evidence of positive selection based on the variable region and not CDR3, whereas A17 was overrepresented because of a rearrangement bias based on molecular mechanisms. Utilization of Jkappa segments was also nonrandom, with Jkappa1 and Jkappa2 being overrepresented and Jkappa3 and Jkappa5 underrepresented in the nonproductive repertoire, implying a molecular basis for the bias. In B cells with two Vkappa Jkappa rearrangements, marked differences were noted in the Vkappa segments used for the initial and subsequent rearrangements, whereas Jkappa segments were used comparably. Junctional diversity was generated by n-nucleotide addition in 60% and by exonuclease trimming in 75% of the Vkappa Jkappa rearrangements analyzed. Despite this large degree of diversity, a strict CDR3 length was maintained in both productive and nonproductive rearrangements. More than 23% of the productive rearrangements, but only 7% of the nonproductive rearrangements contained somatic hypermutations. Mutations were significantly more frequent in Vkappa sequences derived from CD5- as compared with CD5+ B cells. These results document that the gene segment utilization within the Vkappa repertoire is biased by both intrinsic molecular processes as well as selection after light chain expression. Moreover, IgM+ memory cells with highly mutated kappa genes reside within the CD5- but not the CD5+ B cell compartment.


Asunto(s)
Linfocitos B/inmunología , Inmunoglobulina M/análisis , Cadenas kappa de Inmunoglobulina/genética , Antígenos CD5/análisis , Reordenamiento Génico , Humanos , Región de Unión de la Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Memoria Inmunológica , Mutación
7.
J Clin Invest ; 99(10): 2488-501, 1997 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9153293

RESUMEN

To analyze the immunoglobulin repertoire of human IgM+ B cells and the CD5(+) and CD5(-) subsets, individual CD19(+)/ IgM+/CD5(+) or CD5(-) B cells were sorted and non-productive as well as productive VH gene rearrangements were amplified from genomic DNA and sequenced. In both subsets, the VH3 family was overrepresented largely as a result of preferential usage of a small number of specific individual family members. In the CD5(+) B cell subset, all other VH families were found at a frequency expected from random usage, whereas in the CD5(-) population, VH4 appeared to be overrepresented in the nonproductive repertoire, and also negatively selected since it was found significantly less often in the productive compared to the nonproductive repertoire; the VH1 family was significantly diminished in the productive rearrangements of CD5(-) B cells. 3-23/DP-47 was the most frequently used VH gene segment and was found significantly more often than expected from random usage in productive rearrangements of both CD5(+) and CD5(-) B cells. Evidence for selection based on the D segment and the JH gene usage was noted in CD5(+) B cells. No differences were found between the B cell subsets in CDR3 length, the number of N-nucleotides or evidence of exonuclease activity. Somatically hypermutated VHDJH rearrangements were significantly more frequent and extensive in CD5(-) compared to CD5(+) IgM+ B cells, indicating that IgM+ memory B cells were more frequent in the CD5(-) B cell population. Of note, the frequency of specific VH genes in the mutated population differed from that in the nonmutated population, suggesting that antigen stimulation imposed additional biases on the repertoire of IgM+ B cells. These results indicate that the expressed repertoire of IgM+ B cell subsets is shaped by recombinational bias, as well as selection before and after antigen exposure. Moreover, the influences on the repertoires of CD5(+) and CD5(-) B cells are significantly different, suggesting that human peripheral blood CD5(+) and CD5(-) B cells represent different B cell lineages, with similarities to murine B-1a and B-2 subsets, respectively.


Asunto(s)
Linfocitos B/inmunología , Antígenos CD5/sangre , Genes de Inmunoglobulinas , Antígenos HLA-D/genética , Cadenas Pesadas de Inmunoglobulina/genética , Inmunoglobulina M/sangre , Región Variable de Inmunoglobulina/genética , Adulto , Secuencia de Aminoácidos , Animales , Antígenos CD/sangre , Antígenos CD19/sangre , Subgrupos de Linfocitos B/inmunología , Reordenamiento Génico , Humanos , Masculino , Ratones , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa
8.
J Clin Endocrinol Metab ; 70(2): 444-52, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1688867

RESUMEN

A strain of differentiated rat thyroid cells (FRTL5) in continuous culture was used to study the presence of thyroid growth-promoting immunoglobulins (TGI) in the serum of patients with endemic and sporadic euthyroid goiters. To identify true in vitro cell proliferation a microscopic mitotic arrest assay was used. Immunoglobulins G (IgGs) were prepared with QAE-Sephadex A-50 or protein-A-Sepharose. A positive growth stimulation index was found in IgG preparations of 65 of 71 patients with endemic goiter and in 9 of 14 IgG preparations of patients with sporadic goiter. IgG preparations of 15 control subjects from an area where endemic goiter due to iodine deficiency does not occur and of 18 subjects without iodine deficiency and without thyroid enlargement living in the endemic area did not stimulate FRTL5 cell growth. FRTL5 cell growth stimulation with IgGs of these euthyroid goiter patients could only be detected when IgG was tested in combination with a small dose of TSH. Immunoprecipitation with polyclonal and monoclonal antihuman IgG was able to abolish the growth-promoting effects. In 32 blinded samples the Feulgen cytobiochemical assay, formerly used to detect TGI, was compared with the FRTL5 mitotic arrest assay. The two methods showed similar results. Our observations of chromatographically purified IgG promoting thyroid cell proliferation in vitro provide good evidence that IgG was responsible for thyroid cell growth in vitro and suggest that autoimmune growth mechanisms may be involved in the pathogenesis of both endemic and sporadic goiters.


Asunto(s)
Autoanticuerpos/aislamiento & purificación , Bocio Endémico/inmunología , Inmunoglobulina G/aislamiento & purificación , Mitosis/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Adulto , Anciano , Animales , Autoanticuerpos/farmacología , Línea Celular , Densitometría , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Inmunoglobulina G/farmacología , Inmunoglobulinas Estimulantes de la Tiroides , Yodo/farmacología , Masculino , Persona de Mediana Edad , Índice Mitótico/efectos de los fármacos , Coloración y Etiquetado , Glándula Tiroides/citología , Glándula Tiroides/inmunología , Tirotropina/farmacología
9.
Immunobiology ; 188(1-2): 194-202, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8104879

RESUMEN

The present study has been performed to examine the pattern of immune response during and following a long-duration of physical exercise. We have measured plasma concentrations of serum soluble immune activation markers namely soluble interleukin-2 receptor (sIL-2R), soluble CD8 (sCD8), soluble intercellular adhesion molecule 1 (sICAM-1), soluble CD23 (sCD23), soluble tumor necrosis factor receptor (sTNF-R) and neopterin in 18 individuals before, during (ascent: 3 h, descent: 2 h) and after an alpine tour. Compared to baseline levels, all the parameters were significantly increased on top of the mountain and/or after descent. Within 36 hours after the tour sIL-2R, sCD8 and sICAM-1 decreased. In contrast, sTNF-R and neopterin levels remained higher than baseline throughout the study, only partially decreasing 24 and 36 hours from start. These data show immune system activation induced by physical exercise. The increase of parameters sTNF-R and neopterin, reflecting activation of macrophages, was sustained. The data suggest that immune activation phenomena may be involved in the pathogenesis of impaired immune function after exercise and the exercise-induced asthma.


Asunto(s)
Ejercicio Físico , Sistema Inmunológico/fisiología , Esfuerzo Físico , Adulto , Antígenos CD/sangre , Biopterinas/análogos & derivados , Biopterinas/sangre , Antígenos CD8/sangre , Moléculas de Adhesión Celular/sangre , Humanos , Molécula 1 de Adhesión Intercelular , Interleucina-2/sangre , Masculino , Neopterin , Receptores de IgE/metabolismo , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo
10.
J Androl ; 17(2): 158-63, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8723440

RESUMEN

Cytokines released by various cell subsets in the male urogenital tract are capable of markedly influencing sperm function and fertility. We determined the cytokine content in the seminal plasma of patients with unexplained infertility and correlated the results with urogenital infections and sperm parameters. Routine sperm parameters, bacterial culture of seminal plasma and blood follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone were obtained from 14 infertile males and 8 healthy control subjects. Interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF alpha) levels in the seminal plasma were measured by enzyme-linked immunosorbent assay (ELISA). IL-1 beta, IL-6, and TNF alpha levels in the seminal plasma were negatively correlated with the number of progressively motile sperm, but there was no correlation with total sperm counts, viability, pH, morphological alterations, type of abnormality, and hormone parameters. Cytokine levels were significantly elevated in seminal plasma exhibiting bacterial or mycoplasmal infections of the urogenital tract. Urogenital infections lead to an release of inflammatory cytokines, most probably by immunocompetent cells of the lymphocyte/macrophage origin. Cytokines such as IL-1, IL-6, and/or TNF alpha might influence sperm motility via direct or indirect effects, resulting in reduced mucosa penetration properties. Therefore, our data suggest that cytokines may be involved in reduced male fertility.


Asunto(s)
Infertilidad Masculina/etiología , Interleucina-1/análisis , Interleucina-6/análisis , Semen/química , Factor de Necrosis Tumoral alfa/análisis , Adulto , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/fisiopatología , Hormona Folículo Estimulante/análisis , Humanos , Hormona Luteinizante/análisis , Masculino , Enfermedades Urogenitales Masculinas/complicaciones , Enfermedades Urogenitales Masculinas/fisiopatología , Recuento de Espermatozoides , Motilidad Espermática/fisiología , Espermatozoides/citología , Testosterona/análisis
13.
Z Rheumatol ; 67(8): 653-4, 656-7, 2008 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-19015861

RESUMEN

Fibromyalgia syndrome (FMS) and myofascial pain syndrome (MPS) belong to the group of chronic non-inflammatory pain syndromes affecting muscles and tendinous insertions. Important criteria in the diagnosis of both diseases are the presence of "tender points" and "trigger points". According to ACR criteria FMS is characterized by the presence of tender points whereas trigger points are typically found in MPS.The main difference is that until now tender points could only be defined in terms of their localization, whereas trigger points can be found upon palpation which may cause a specific referred pain pattern. In addition, analysis of trigger points by microdialysis demonstrated elevated levels of pro-inflammatory substances at these sites. Moreover, local treatment of trigger points either by manipulative therapy or injection appears to be most effective for prompt relief of symptoms.


Asunto(s)
Fibromialgia/fisiopatología , Síndromes del Dolor Miofascial/fisiopatología , Tejido Conectivo/fisiopatología , Diagnóstico Diferencial , Fibromialgia/diagnóstico , Fibromialgia/terapia , Humanos , Mediadores de Inflamación/metabolismo , Músculo Esquelético/fisiopatología , Síndromes del Dolor Miofascial/diagnóstico , Síndromes del Dolor Miofascial/terapia , Dolor Referido/fisiopatología , Palpación , Sustancia P/metabolismo
14.
Ann Rheum Dis ; 64(8): 1224-6, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16014683

RESUMEN

OBJECTIVE: To determine the effect on the humoral immune system of long term treatment of patients with RA with etanercept. METHODS: 12 consecutive patients with seropositive RA treated with etanercept were studied and followed up for 9 months. Clinical efficacy of treatment was evaluated using the 28 joint count Disease Activity Score (DAS28). Serum samples were collected at baseline and after 9 months and serum immunoglobulin, RF isotypes, and anti-cyclic citrullinated peptide (aCCP), antinuclear, nucleosome, and dsDNA antibodies determined. For comparison 7 patients with seropositive RA treated with adalimumab were studied. RESULTS: DAS28 decreased significantly after the first month and then was constant for the whole study (5.7 (0.3) v 3.8 (0.2), p< or=0.000). Serum IgA-RF and IgG-RF increased significantly after 9 months' etanercept treatment (mean (SEM) IgA-RF rose from 19.5 (4.8) to 30.5 (5.9) IU/ml, p< or=0.01; IgG-RF from 20.6 (8.1) to 33.8 (11.5) IU/ml, p< or=0.04). Serum levels of total immunoglobulin and specific autoantibodies remained unchanged during the study. In patients treated with adalimumab, no significant changes in serum levels of RF isotypes and aCCP antibodies were seen. CONCLUSION: Etanercept, although effective in treating the clinical symptoms of RA, seems to have a pivotal effect on RF-producing B cells either directly or indirectly.


Asunto(s)
Antirreumáticos/farmacología , Artritis Reumatoide/inmunología , Autoanticuerpos/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Anciano , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Autoanticuerpos/sangre , Etanercept , Femenino , Estudios de Seguimiento , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina G/farmacología , Inmunoglobulina G/uso terapéutico , Masculino , Persona de Mediana Edad , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Factor Reumatoide/sangre , Índice de Severidad de la Enfermedad
15.
J Immunol ; 155(1): 190-202, 1995 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-7602095

RESUMEN

The VH gene repertoire of human peripheral B cells was analyzed using PCR analysis of individual blood B cells. Because genomic DNA of single B cells was analyzed, data from both productive and nonproductive VDJ rearrangements were obtained. Nine out of 75 B cells contained both functional and nonfunctional rearrangement products, whereas 62/75 had a single productive VDJ rearrangement. The distribution of VH families was ordered in accordance with the germline complexity, although a bias toward VH3 and some of its members was found. This bias was noted in both the productively and nonproductively rearranged repertoires, indicating that it resulted from molecular and not selective processes. Evidence for negative selection of certain VH3 and VH4 family members was noted in that they were found less often as productive than nonproductive VDJ rearrangements. In addition, evidence for positive selection based on CDR3 was obtained, in that JH6 and DXP'1 were found at a higher frequency in the productively compared with the nonproductively rearranged repertoire. The CDR3 segments were markedly heterogenous, with a much greater degree of variability noted in the nonproductive VDJ rearrangements. Finally, a much greater frequency of mutations was noted in the nonproductively rearranged VH genes within individual B cells. These results have begun to delineate the human peripheral B cell repertoire and identify processes that shape it both positively and negatively.


Asunto(s)
Linfocitos B/inmunología , Cadenas Pesadas de Inmunoglobulina/análisis , Cadenas Pesadas de Inmunoglobulina/genética , Secuencia de Bases , Femenino , Citometría de Flujo , Amplificación de Genes/genética , Reordenamiento Génico de Cadena Pesada de Linfocito B/genética , Genes de Inmunoglobulinas , Humanos , Región Variable de Inmunoglobulina/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos
16.
Int Immunol ; 12(6): 767-75, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10837404

RESUMEN

Analysis of the V(H)DJ(H) repertoire of peripheral blood IgM(+) B cells from a patient with X-linked hyper-IgM syndrome (X-HIgM) was undertaken to determine whether the distribution of V(H) families in the productive repertoire might be regulated by in vivo CD40-CD154 interactions. The distribution of V(H) genes in the non-productive repertoire of IgM(+) B cells was comparable in X-HIgM and normals. Unlike the normal productive V(H) repertoire, however, in the X-HIgM patient the V(H)4 family was found at almost the same frequency as the V(H)3 family. This reflected a diminution in the positive selection of the V(H)3 family observed in normals and the imposition of positive selection of the V(H)4 family in the X-HIgM patient. Unique among the V(H)3 genes, V(H)3-23/DP-47 was positively selected in both normals and the X-HIgM patient. No major differences in the usage of J(H) or D segments or the complementarity-determining region (CDR) 3 were noted, although the foreshortening of the CDR3 noted in the mutated V(H) rearrangements of normals was absent in the X-HIgM patient. Finally, a minor degree of somatic hypermutation was noted in the X-HIgM patient. These results have suggested that specific influences on the composition of the V(H) repertoire in normals require CD40-CD154 interactions.


Asunto(s)
Antígenos CD40/fisiología , Genes de Inmunoglobulinas , Ligamiento Genético , Hipergammaglobulinemia/genética , Cadenas Pesadas de Inmunoglobulina/genética , Inmunoglobulina M/sangre , Región Variable de Inmunoglobulina/genética , Glicoproteínas de Membrana/fisiología , Cromosoma X , Ligando de CD40 , Preescolar , Humanos , Masculino , Mutación
17.
Gen Comp Endocrinol ; 88(2): 188-98, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1335939

RESUMEN

An altered immunoendocrine feedback regulation within the hypothalamo-pituitary-adrenal axis may modulate the pathogenesis of an avian autoimmune disease. To date studies have been hampered by a lack of reliable, specific, and sensitive methods for determining adrenocorticotropic hormone (ACTH) in chickens. The present study describes the determination of ACTH in plasma of chickens with a commercial radioimmunoassay, the antibody of which binds to the midregion of human ACTH 1-39. The chickens, kept on a 12-hr day and 12-hr night shift with artificial light, showed changes in plasma ACTH concentrations during the light phase with maximum values 8 hr after the light was turned on. ACTH was not measurable after treatment with dexamethasone. Intravenous administration of supernatants from concanavalin A-stimulated spleen cells increased basal plasma ACTH concentrations more than 20-fold within 1 hr. This increase in plasma ACTH was higher and longer lasting in UCD 200 chickens, an animal model for scleroderma, compared with outbred and inbred normal White Leghorn chickens.


Asunto(s)
Hormona Adrenocorticotrópica/sangre , Enfermedades Autoinmunes/veterinaria , Pollos/inmunología , Enfermedades de las Aves de Corral/inmunología , Animales , Enfermedades Autoinmunes/sangre , Extractos Celulares , Corticosterona/sangre , Dexametasona/farmacología , Modelos Animales de Enfermedad , Retroalimentación , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/metabolismo , Ensayo Inmunorradiométrico , Interleucina-1/farmacología , Luz , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/metabolismo , Radioinmunoensayo , Esclerodermia Sistémica/sangre , Bazo/fisiología , Factores de Tiempo
18.
J Immunol ; 160(10): 4762-7, 1998 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9590222

RESUMEN

A functional Ig consists of two heterodimers each of which is composed of a heavy and a light chain. Although there is increasing knowledge about the events that govern the rearrangement of the genes encoding each individual chain, only very limited information is available about the mechanisms governing the pairing of variable heavy (V(H)) and variable light (V(L)) chains. Using a single cell PCR, we were able to obtain V(H) and Vkappa chains from 144 individual human CD19+/IgM+ B cells. Pairing of specific V(H) or Vkappa families was not observed, nor was the length or the amino acid composition of the CDR3s of V(H) and Vkappa chains in individual B cells similar. Comparison of V(H) and Vkappa genes in B cells in which one or both contained evidence of somatic hypermutation with those with no mutations revealed a significant decrease in the mean length of the V(H) CDR3. Moreover, there was a significant correlation between the frequencies of mutations in V(H) and Vkappa gene pairs in individual B cells. These results indicate that Ag-mediated selection as opposed to V(H)DJ(H) recombination or subsequent Ig chain pairing tended to approximate the CDR3 lengths and the frequency of mutations of V(H) and Vkappa in individual B cells.


Asunto(s)
Linfocitos B/fisiología , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Memoria Inmunológica , Adulto , Reordenamiento Génico , Humanos , Masculino , Persona de Mediana Edad
19.
Immunol Rev ; 162: 161-71, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9602362

RESUMEN

B cells are unique in that they generate and tolerate a high rate of mutations in their antigen receptor genes and employ these mutations as a basis of avidity maturation. The precise role of the mutational machinery versus subsequent selection in determining the frequency and distribution of mutations has not been fully analyzed. To address these issues, the influence of the intrinsic mutational machinery and subsequent selection on the frequency and distribution of mutations in the expressed human immunoglobulin repertoire was analyzed. Analysis of non-productively rearranged VH genes from individual human B cells provided an opportunity to examine the immediate impact of somatic hypermutation without superimposed selective influences. Comparison with the frequency and distribution of mutations in the productively rearranged human VH genes permitted an estimate of the influences of subsequent selection.


Asunto(s)
Cadenas Pesadas de Inmunoglobulina/genética , Cadenas J de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Cadenas delta de Inmunoglobulina/genética , Mutación , Linfocitos B/inmunología , Secuencia de Bases , Codón , Reordenamiento Génico , Humanos , Datos de Secuencia Molecular
20.
J Steroid Biochem ; 30(1-6): 375-9, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3260312

RESUMEN

Obese strain (OS) chickens afflicted with spontaneous autoimmune thyroiditis (SAT) display several signs of a general immune dysbalance, some of which may be related to altered endocrine mechanisms such as the glucocorticoid tonus. The latter is the combined result of corticosterone (CN) production, metabolism as well as excretion, and the binding of CN to corticosteroid binding globulin (CBG) and glucocorticoid receptors (GR). The present study deals with the comparative investigation of these parameters in OS and normal White Leghorn (NWL) chickens. The results obtained with radioimmunoassay for CN and radioligand saturation assays for plasma CBG as well as GR in the thymus were as follows: (1) both OS and NWL have equal total CN levels; (2) however, OS chickens exhibit elevated CBG levels, whereas the physicochemical parameters (equilibrium affinity, specificity spectrum) of CBG were equal in OS and NWL; (3) the GR capacities and affinities were equal in both OS and NWL throughout development until thymic involution. Similarly, the specificity, affinity, and sedimentation behaviour were equal in OS and NWL. (4) Furthermore, no differences were found in the response of OS and NWL splenocytes to the suppressive effect of glucocorticoids in vitro, also excluding postreceptor alterations at the cellular level in the OS. From these findings we conclude that the increased CBG levels, which are not compensated for by either increased CN plasma levels or by increased receptor capacities or affinities in lymphatic organs, represent a diminished glucocorticoid tonus in OS chickens. This may have immunoregulatory consequences which, in turn, may contribute to the development of SAT.


Asunto(s)
Corticosterona/sangre , Glucocorticoides/fisiología , Obesidad/fisiopatología , Receptores de Glucocorticoides/metabolismo , Timo/metabolismo , Tiroiditis Autoinmune/fisiopatología , Transcortina/metabolismo , Animales , Pollos , Obesidad/inmunología , Especificidad de la Especie , Linfocitos T/inmunología
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