title: Adult-onset cyclic neutropenia is a benign neoplasm associated with clonal proliferation of large granular lymphocytes.
abstract: Human cyclic neutropenia occurs in children and adults. Adult-onset cyclic neutropenia is an acquired disease characterized by increased numbers of large granular lymphocytes (LGL), in contrast to childhood-onset cyclic neutropenia in which LGL counts are normal. We investigated the clonality of lymphocytes in these two groups of patients by assessing the rearrangement status of the T cell receptor beta chain gene. Patients with adult-onset cyclic neutropenia showed clonal rearrangement of the T beta gene whereas the children did not. Since LGL are known to have multiple regulatory effects on normal hematopoiesis, the finding of a clonal proliferation of this lymphocyte population implicates these cells in the pathogenesis of cyclic neutropenia.
mesh_terms: D000328:Adult; D000380:Agranulocytosis / Q000235:genetics*; D002874:Chromosome Mapping; D002999:Clone Cells; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004273:DNA, Neoplasm / Q000032:analysis; D015245:Deoxyribonuclease BamHI; D015246:Deoxyribonuclease EcoRI; D006801:Humans; D008214:Lymphocytes / Q000473:pathology*; D009369:Neoplasms / Q000235:genetics* / Q000473:pathology; D009503:Neutropenia / Q000235:genetics* / Q000473:pathology
chemical_list: D004273:DNA, Neoplasm; D004262:DNA Restriction Enzymes; D015245:Deoxyribonuclease BamHI; D015246:Deoxyribonuclease EcoRI