Retention and loss of immunoglobulin heavy chain alleles in helper T cell hybridoma clones.

Abstract

Retention or loss of immunoglobulin heavy chain genes was studied in 20 functional T cell hybridoma clones. DNA probes representing C mu, C alpha and JH genes, as well as VH subgroups II and III were hybridized with restriction enzyme fragments of hybridoma DNA by the Southern filter hybridization technique. Parental alleles of the hybridoma cells were distinguished on the basis of polymorphism of the lengths of restriction enzyme fragments. All clones retained the alleles of the lymphoma parent cell BW‐5147 at all four loci. Thirteen clones lost both CH and VH alleles of the immune partner cell, whereas seven retained both VH alleles, and at least C alpha of the antigen‐specific partner. Hence, T cell function in these cells is compatible with the loss of most immunoglobulin heavy chain alleles. This is interpreted to indicate either gene rearrangement and deletion, or chromosome loss. Accordingly, the T cell receptor is either controlled by two split gene loci in chromosome 12, at the two respective (5′ and 3′) ends of the mouse heavy chain gene family, or by a gene(s) outside chromosome 12.

Mass spectrometry of peptides and proteins from human blood

“…Each gene, its mRNA, and protein are uniquely regulated at multiple levels including transcriptional, post-transcriptional, translational, post-translational, processing and turnover in response to developmental, physiological or environmental conditions (Gygi et al, 1999b). Re-arrangements at the level of nucleic acids as well as post-translation modifications and processing give rise to an immense number of possible proteins, and complexes, expressed in different tissues and cell types (McClintock, 1941;Urbain, 1969;Ono, 1972;Tonegawa et al, 1974;Cech, Zaug, & Grabowski, 1981;Lonai et al, 1983;Kavaler, Davis, & Chien, 1984;Hakomori, 1996;Hagen & Cech, 1999;Schmucker et al, 2000;Haglund, Ek, & Ek, 2001;Pawson & Nash, 2003;Machida et al, 2007). The International Protein Index (IPI; Kersey et al, 2004), was conceived as an integrated database for proteomics and built as a complete and non-redundant (NR) compilation of the Swiss-Prot, TrEMBL, Ensembl and RefSeq databases (Maglott et al, 2000;Wheeler et al, 2003;Pruitt, Tatusova, & Maglott, 2007).…”

Editorial

“…Disappointingly, they do so by adopting the same unscientific procedure that they blame others for having used: they interpret data beyond what they formally mean. I will just mention two examples: Lonai et al, [3] have published evidence that 13 out of 20 T-cell hybridomas with antigen-specific functions did not contain DNA that hybridizes to probes specific for several CH genes, JH genes, and VH genes, suggesting that these hybridomas had lost all or most ofthe immunoglobulin H-chain genes. Coutinho & Meo quote this work by writing that these hybridomas 'have lost chromosome 12' and 'see no reason for [the] undue conservatism in the interpretation' given by Lonai et al…”

Production and characterization of cloned T-cell hybridomas that are responsive to Rickettsia conorii antigens

“…Clones were picked from the plates containing 0.25 cells per well, and those that responded well to the immunizing antigen were then tested for specificity against the battery of antigens listed above at concentrations of 250, 100, 50, 10, and 1 ,ug/ml. Because of the reported instability of T-cell hybridomas (25) and based on our own experience, we routinely subcloned our hybridomas by limiting dilution every 3 to 4 weeks.…”