Abnormalities of adherent layers grown from bone marrow of patients with myelodysplasia.
Myelodysplastic syndromes (MDS) are characterized by a clonal disorder of haemopoiesis with defective growth in vitro. The long-term culture system was used to examine aspects of stromal function in MDS patients. Primary long-term cultures of MDS bone marrow showed poor myelopoiesis with progenitors being detected for a median 3.5 weeks (n = 12) compared with 18 weeks in cultures of normal marrow (n = 10; P < 0.0001). The haemopoietic function of adherent layers was assessed in secondary co-cultures seeded with 5 x 10(6) cord blood mononuclear cells on irradiated normal (n = 27; aged 38-82 years) or MDS (n = 32; aged 41-86 years) adherent layers (> 60% confluent). The median myeloid progenitor number/cord blood co-culture was 135 in 5-week-old cultures with normal adherent layers and 22 in those with MDS layers (P < 0.0001). Myeloid colonies were detectable for a median 11 weeks with normal adherent layers and 6 weeks with MDS adherent layers (P < 0.0001); erythroid colonies were detectable for 7 weeks (normal) compared with 5 weeks (MDS) (P < 0.01). The differences in granulocyte-macrophage colony forming unit (CFU-GM) generation were not related to patient age. Cells from adherent layers of at least half of the primary normal (n = 48) and MDS (n = 26) long-term cultures expressed cytokines [interleukin (IL)-3, IL-1 beta, thrombopoietin (Tpo) and erythropoietin (Epo)] and receptors for retinoic acid (RAR alpha) [IL-2, IL-3, macrophage colony stimulating factor (M-CSF) (Fms) and Tpo (Mpl)]. Only IL-1 beta expression was reduced in week-5 MDS cultures compared with those from normal marrows (P < 0.05). There was also a highly significant decline in IL-1 beta expression in normal (but not MDS) adherent layers between week 5 and week 10. Thus, the adherent layers in cultures grown from MDS patients were haemopoietically defective and showed abnormal IL-1 beta expression.
Tennant
G B
GB
Department of Haematology, University of Wales College of Medicine, Cardiff, UK. Tennant@Cardiff.ac.uk
Walsh
V
V
Truran
L N
LN
Edwards
P
P
Mills
K I
KI
Burnett
A K
AK
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002448:Cell Adhesion; D018920:Coculture Techniques; D004921:Erythropoietin / Q000378:metabolism; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D007377:Interleukin-3 / Q000378:metabolism; D016014:Linear Models; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000276:immunology / Q000473:pathology*; D023461:Myeloid Progenitor Cells / Q000276:immunology / Q000473:pathology*; D018121:Receptors, Cytokine / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D013926:Thrombopoietin / Q000378:metabolism; D013997:Time Factors
D007375:Interleukin-1; D007377:Interleukin-3; D018121:Receptors, Cytokine; D004921:Erythropoietin; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013926:Thrombopoietin