Morphological, genetic and functional variability of a T-cell hybridoma line.
The variability in the morphology, modal number of chromosomes, TCR expression and functional reactivity of a CII-specific T-cell hybridoma at continuous subcultivation have been investigated. As the number of passages increased, besides the oval semiadherent cells (normal phenotype), fibroblast-like cells (transformed phenotype) were also observed. The two cell subpopulations differed in their karyotype characteristic, as well as in their functional reactivity. The cell population with a normal phenotype was characterized by a tetramodal number of chromosomes (30, 40, 48 and 70) and trisomies of chromosomes 6 and 14, while the cell population with a transformed phenotype was characterized by a trimodal number of chromosomes (11, 68 and 74) and trisomy of chromosome 12. A nullisomy of sex chromosomes was established in both types of cells. In the initial passages of subcultivation, 73.04% of the cells with a normal morphological phenotype expressed TCR-CD3 complexes on their surface and possessed high functional reactivity. After a two-week subcultivation, the values of these indices went down considerably: 46.11% of the cells expressed functional TCR-CD3 complexes, as a result of which their functional reactivity decreased. Only 2.71% of the cells with a transformed morphological phenotype expressed functional TCR-CD3 complexes on their surface. In these cells, a total loss of reactivity towards the specific antigens was established. The achieved results show that at continuous subcultivation the T-cell hybridomas are unstable, and with the increase in the number of passages there appear chromosome rearrangements, leading to loss of their functional reactivity.
Dzhambazov
B
B
Section for Medical Inflammation Research, Department of Cell and Molecular Biology, Lund University, Lund, Sweden. Balik.Dzhambazov@inflam.lu.se
Teneva
I
I
Koleva
L
L
Asparuhova
D
D
Popov
N
N
D000818:Animals; D048429:Cell Size / Q000235:genetics; D002869:Chromosome Aberrations; D014644:Genetic Variation / Q000235:genetics*; D042822:Genomic Instability / Q000235:genetics / Q000276:immunology; D005838:Genotype; D006825:Hybridomas / Q000166:cytology* / Q000378:metabolism*; D007111:Immunity, Cellular / Q000235:genetics; D051379:Mice; D010641:Phenotype; D051381:Rats; D017260:Receptor-CD3 Complex, Antigen, T-Cell / Q000235:genetics / Q000276:immunology; D012729:Sex Chromosome Aberrations; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D014314:Trisomy / Q000235:genetics
D017260:Receptor-CD3 Complex, Antigen, T-Cell