Extending Jak2V617F and MplW515 mutation analysis to single hematopoietic colonies and B and T lymphocytes.
JAK2V617F and MPLW515L/K are myeloproliferative disorder (MPD)-associated mutations. We genotyped 552 individual hematopoietic colonies obtained by CD34+ cell culture from 16 affected patients (13 JAK2V617F and 3 MPLW515L/K) to determine (a) the proportion of colonies harboring a particular mutation in the presence or absence of cytokines, (b) the lineage distribution of endogenous colonies for each mutation, and (c) the differences (if any) in the pattern of mutation among the various MPDs, as established by genotyping of individual colonies. Genotyping analysis revealed cohabitation of mutation-negative and mutation-positive endogenous colonies in polycythemia vera as well as other MPDs. Culture of progenitor cells harboring MPLW515L/K yielded virtually no endogenous erythroid colonies in contrast to JAK2V617F-harboring progenitor cells. The mutation pattern (i.e., relative distribution of homozygous, heterozygous, or wild-type colonies) was not a distinguishing feature among the MPDs, and MPLW515 mutations were detected in B and/or T lymphocytes in all three patients tested. These observations suggest that clonal myelopoiesis antedates acquisition of JAK2V617F or MPLW515L/K mutations and that the latter is acquired in a lympho-myeloid progenitor cell.
Pardanani
Animesh
A
Division of Hematology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA.
Lasho
Terra L
TL
Finke
Christy
C
Mesa
Ruben A
RA
Hogan
William J
WJ
Ketterling
Rhett P
RP
Gilliland
Dwight Gary
DG
Tefferi
Ayalew
A
D019943:Amino Acid Substitution; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D001483:Base Sequence; D002478:Cells, Cultured; D002999:Clone Cells / Q000378:metabolism; D004252:DNA Mutational Analysis; D006410:Hematopoiesis / Q000235:genetics; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics* / Q000378:metabolism; D017354:Point Mutation; D011087:Polycythemia Vera / Q000235:genetics; D055728:Primary Myelofibrosis / Q000235:genetics; D053628:Receptors, Thrombopoietin / Q000235:genetics* / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D014364:Tryptophan / Q000235:genetics; D014633:Valine / Q000235:genetics
D053628:Receptors, Thrombopoietin; C082218:MPL protein, human; D014364:Tryptophan; C507924:JAK2 protein, human; D053614:Janus Kinase 2; D014633:Valine