Comparison of immunological abnormalities of lymphocytes in bone marrow in myelodysplastic syndrome (MDS) and aplastic anemia (AA).
OBJECTIVE
The subsets and the polarization of lymphocytes in bone marrow from low-risk myelodysplastic syndrome (MDS) were studied and compared with those from patients with aplastic anemia (AA).


METHODS
A total of 34 patients with low-risk MDS (IPSS score< or =1.0) who presented abnormal chromosomes and 16 patients with AA were enrolled in this study. We determined T lymphocyte subsets, T cells polarization status, and the percentages of NK cells and of B lymphocytes in bone marrow and compared these parameters between the two groups of patients. As controls, 24 patients with high-risk MDS (IPSS score>1.0) presenting abnormal chromosomes and 22 healthy/benign hematologic disease subjects were used.


RESULTS
In low-risk MDS/AA patients, the percentage of CD3+ lymphocytes was significantly increased compared to controls (p=0.006 and p=0.001), while the percentage of CD19+ lymphocytes was significantly decreased (p<0.001 and p=0.002); there were no significant differences between MDS/AA and normal controls in other parameters; For low-risk MDS patients, the polarization status of bone marrow CD4+ cells toward Th1 (Th1/Th2) and of CD8+ cells toward Tc1 (Tc1/Tc2) was stronger than that for AA patients (p=0.05 and p<0.001). Other parameters did not show significant differences; Regardless of the predominance of CD4 or CD8 T cells, all patients with low-risk MDS were accompanied with elevated Tc1 polarization (Tc1/Tc2).


CONCLUSIONS
In both AA and MDS, the number of total T lymphocytes increased. However, polarization towards Th1 and Tc1 was obviously stronger in MDS patients than in AA patients. This might be related to T cell stimulation from the clones of malignant hematopoietic cells.
Li
Xiao
X
Department of Hematology, Sixth Hospital Affiliated to Shanghai Jiaotong University, China. lixiao3326@yahoo.com.cn
Xu
Feng
F
He
Qi
Q
Wu
Lingyun
L
Zhang
Zheng
Z
Chang
Chunkang
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000741:Anemia, Aplastic / Q000175:diagnosis / Q000235:genetics / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology* / Q000473:pathology*; D002648:Child; D002869:Chromosome Aberrations; D005260:Female; D006801:Humans; D016131:Lymphocyte Subsets / Q000276:immunology* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000175:diagnosis / Q000235:genetics / Q000276:immunology*; D055815:Young Adult