Molecular analysis of TCR clonotypes in LGL: a clonal model for polyclonal responses.
Large granular lymphocytic (LGL) leukemia is a clonal lymphoproliferative disorder of CTL associated with cytopenias resulting from an immune and cytokine attack on hemopoietic progenitor cells. Extreme clonality of CTL expansions seen in LGL leukemia makes it an ideal model to study the role of the T cell repertoire in other less-polarized immune-mediated disorders. Complementarity-determining region 3 (CDR3) of the TCR is a unique Ag-specific region that can serve as a molecular marker, or clonotype, of the disease-specific T cells. We studied the variable portion of the beta-chain spectrum in a cohort of LGL leukemia patients. The CDR3 sequences were determined for the immunodominant clones and used to design clonotype-specific primers. By direct and semi-nested amplification, clonotype amplicons were found to be shared by multiple patients and controls. Analysis of the generated sequences demonstrated that the original clonotypes are rarely encountered in normal control samples; however, high levels of homology were found in both controls and patients. Clonotypes derived from individual LGL patients can be used as tumor markers for the malignant clone. More generally, clonotypic analysis and comparison of the variable portion of the beta-chain CDR3-specific sequences from a large number of patients may lead to better subclassification of not only LGL but also other immune-mediated disorders.
O'Keefe
Christine L
CL
Experimental Hematology and Hematopoiesis Section, and Hematopathology Section, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
Plasilova
Magdalena
M
Wlodarski
Marcin
M
Risitano
Antonio M
AM
Rodriguez
Alexander R
AR
Howe
Evan
E
Young
Neal S
NS
Hsi
Eric
E
Maciejewski
Jaroslaw P
JP
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002455:Cell Division / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D002999:Clone Cells; D003001:Cloning, Molecular / Q000379:methods; D022801:Complementarity Determining Regions / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007945:Leukemia, Lymphoid / Q000188:drug therapy / Q000235:genetics / Q000276:immunology* / Q000473:pathology*; D015458:Leukemia, T-Cell / Q000188:drug therapy / Q000235:genetics / Q000276:immunology* / Q000473:pathology*; D007970:Leukopenia / Q000235:genetics / Q000276:immunology / Q000473:pathology; D008213:Lymphocyte Activation / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D011948:Receptors, Antigen, T-Cell / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*
D022801:Complementarity Determining Regions; D007166:Immunosuppressive Agents; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta