Molecular studies on LAK cells.
We have developed a culture system for long-term growth of human LAK cells exhibiting an elevated, wide-spectrum anti-tumor cytotoxicity. The phenotypic and molecular properties of the final LAK cell populations indicated that they consist of three main types: a) NK-like lymphocytes (type I): NKH-1+, Ti alpha/beta-, Ti gamma/delta-, CD3-lymphocytes carrying the germline configuration of all TCR genes and expressing variable amount of the 1.0 beta mRNA and variably sized T delta transcripts; b) gamma/delta-like T lymphocytes (type II) NKH-1+, Ti alpha/beta-, Ti gamma/delta+, CD3+ lymphocytes carrying polyclonal rearrangements of the gamma and delta genes and expressing high levels of mature gamma and delta transcripts; c) alpha/beta-like T lymphocytes (type III): NKH-1+, Ti alpha/beta+, Ti gamma/delta-, CD3+ lymphocytes carrying rearrangements of all TCR genes and expressing high levels of mature alpha and beta transcripts. We took advantage of the high number of available LAK cells to clarify: 1) the origin of the NK-LAK delta transcripts. delta gene expression in LGL, NK clones and type I LAK cultures revealed six delta transcripts (3.5, 3.1, 2.2, 2.0, 1.5 and 1.3 kb), which varied in number and relative abundance in the different samples. None of the six known V delta was expressed and the delta locus was retained in its germline configuration suggesting that the delta expression is due to a partially rearranged or germline transcripts; 2) the origin of the NK-LAK truncated T beta transcript. We isolated two different clone types from a type I LAK cell cDNA library: a) J-C clones consisting of one of three J beta regions and the corresponding C beta 1 or C beta 2 regions; b) X-J-C and C-X clones, containing as yet unidentified (X) sequences. The presence of RSSs in J-C clones suggests that they derive from mRNAs transcribed from a promoter in the 5'J. Nucleotide analysis demonstrated that only one of the isolated clones had the potential to code a short T beta protein.
Fagioli
M
M
Istituto di Clinica Medica I, Università degli Studi di Perugia, Policlinico Monteluce, Italy.
Carè
A
A
Ciccone
E
E
Moretta
L
L
Moretta
A
A
Testa
U
U
Falini
B
B
Grignani
F
F
Peschle
C
C
Pelicci
P G
PG
D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D004247:DNA / Q000235:genetics; D015342:DNA Probes; D005786:Gene Expression Regulation; D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology* / Q000637:transplantation; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D008969:Molecular Sequence Data; D011061:Poly A / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000096:biosynthesis / Q000235:genetics; D016692:Receptors, Antigen, T-Cell, gamma-delta; D011994:Recombinant Proteins / Q000494:pharmacology
D015342:DNA Probes; D007376:Interleukin-2; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta; D011994:Recombinant Proteins; D011061:Poly A; D004247:DNA