Development of a human T-cell hybridoma secreting separate B-cell growth and differentiation factors.

AUTOR(ES)

Butler, J L

RESUMO

A cloned human T-cell hybridoma (7D5) secreting B-cell growth factor (BCGF) and B-cell differentiation factor (BCDF) was established. Supernatant from this hybrid was capable of maintaining proliferation in anti-IgM-activated normal human B cells. In addition, the hybridoma supernatant induced differentiation and antibody secretion in Staphylococcus aureus Cowan I-stimulated B cells. No interleukin 2 was present in supernatant from this hybridoma. Molecular size of the hybridoma-derived BCGF and BCDF was determined by gel filtration chromatography. BCGF activity was present in the 20-kDa fractions, and BCDF activity eluted in the 30- to 35-kDa fractions. The isoelectric points of the factors, determined by chromatofocusing, were 6.6 for BCGF and 5.9 for BCDF. Finally, absorption experiments were performed using specific target cells. Phytohemagglutinin-stimulated T-cell blasts did not remove either BCGF or BCDF activity. Anti-IgM-activated B cells absorbed BCGF but not BCDF. In contrast, CESS cells removed BCDF but not BCGF. Thus, a human T-cell hybridoma secreting two distinct B-cell lymphokines was developed. Further immunochemical and functional studies of these immunoregulatory molecules should greatly enhance our understanding of the regulation of human B-cell function in normal and disease states.

Documentos Relacionados

• B-cell growth factor: distinction from T-cell growth factor and B-cell maturation factor.
• Two separate functions of class II (Ia) molecules: T-cell stimulation and B-cell excitation.
• Analysis of the human T-cell response to picornaviruses: identification of T-cell epitopes close to B-cell epitopes in poliovirus.
• T-cell and mast cell lines respond to B-cell stimulatory factor 1.
• Induction of proliferation and differentiation of neoplastic B cells by anti-immunoglobulin and T-cell factors.