RESUMEN
Recent studies have been carried out to delineate further the role of the Rb1 gene in B-cell chronic lymphocytic leukaemia (B-CLL). The suggested role of the Rb1 gene in this disease was based on cytogenetic data. CLL patients (40 in toto) were examined using cytogenetic and molecular biological methods. R-banding analysis of metaphase chromosomes revealed aberrations in only seven cases containing either the Rb1 gene or a chromosome 13 monosomy. No evident differences were found by RT-PCR analysis of Rb1 gene expression. The amounts of the RT-PCR products obtained appeared to be approximately equal in all cases, and was independent of the clinical stage, immunophenotypes and LPS or TPA stimulation.
Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 13/genética , Regulación Leucémica de la Expresión Génica/genética , Genes de Retinoblastoma/genética , Leucemia Linfocítica Crónica de Células B/genética , Células Cultivadas , Aberraciones Cromosómicas/genética , Bandeo Cromosómico , Femenino , Humanos , Inmunofenotipificación , Cariotipificación , Linfocitos , Masculino , Reacción en Cadena de la Polimerasa , ARN Mensajero/sangre , ARN Neoplásico/sangreRESUMEN
The in vitro production and secretion of the immunoglobulins IgM, IgG, Kappa and lambda light chains by peripheral blood lymphocytes from chronic lymphocytic leukaemia patients was examined. The ELISA system was employed to quantitate the immunoglobulins secreted in the culture supernatants. Lipopolysaccharide and phorbol esters with CA++ ionophore were used as lymphocyte stimulators. The maturation of cultured lymphocytes was demonstrated by synthesis of cytoplasmic immunoglobulins and Ig secretions typical for plasma cells. In one case an isotype switch C mu for C gamma was observed.
Asunto(s)
Linfocitos B/inmunología , Inmunoglobulinas/metabolismo , Transducción de Señal/inmunología , Linfocitos B/citología , Linfocitos B/metabolismo , Diferenciación Celular/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G/metabolismo , Inmunoglobulina M/metabolismo , Cadenas kappa de Inmunoglobulina/metabolismo , Cadenas lambda de Inmunoglobulina/metabolismo , Inmunoglobulinas/biosíntesis , Inmunofenotipificación , Leucemia de Células B , Leucemia Linfocítica Crónica de Células B , Lipopolisacáridos/farmacología , Activación de Linfocitos/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/inmunologíaRESUMEN
Lipopolysaccharide (LPS) and phorbol esters (TPA) stimulate lymphocytes proliferation in two different ways. While LPS primary function is specific receptor binding, TPA directly activate cellular protein kinase C. The stimulation of human leukaemic lymphocytes (from chronic lymphocytic leukaemia patients) with LPS and TPA results in two different types of response: to both stimulators, and to LPS only. Therefore the supposed defect of cellular receptors can not explain all the observed effects. The existence of TPA independent second messengers and changes in signal transduction pathways downstream of PKC can be considered.