ABSTRACT
<p><b>OBJECTIVE</b>To detect the quantity, proportion and function of producing cytokines of Th1 and Th2 cells in aplastic anemia (AA) patients and their contribution to the hematopoietic failure.</p><p><b>METHODS</b>(1) Eleven patients with severe aplastic anemia (SAA) at diagnosis were observed by Marsh's method for the CFU-E, BFU-E and CFU-GM before and after depletion of CD(4)(+) T lymphocytes from bone marrow mononuclear cells (BMMNC); (2) Th1 (CD(4)(+) IFN-gamma(+)) and Th2 (CD(4)(+) IL-4(+)) cells in peripheral blood mononuclear cells (PBMNC) of 21 SAA patients and 17 normal controls were counted by FACS. (3) mRNA expression of IFN-gamma and IL-4 gene in unstimulated BMMNC from 16 SAA patients, 11 chronic aplastic anemia (CAA) patients, 26 other hematological diseases patients and 11 normal controls were measured by reverse transcriptase polymerase chain reaction (RT-PCR).</p><p><b>RESULT</b>(1) CFU-E, CFU-GM and BFU-E increased significantly after depletion of CD(4)(+) T lymphocytes from BMMNC of SAA patients. (2) The percentage of IFN-gamma producing CD(4)(+) T cell (Th1) of SAA patients was significantly higher than that of controls, the percentages of IL-4 producing CD(4)(+) T cells (Th2) had no difference between SAA patients and normal controls. (3) IFN-gamma mRNA was detected in unstimulated BMMNC in 13 of 16 SAA patients, 6 of 11 CAA patients and one of 6 paroxysmal nocturnal hemoglobinuria (PNH) patients. The IFN-gamma mRNA was not detected in unstimulated BMMNC of 11 normal controls and other hematological diseases patients.</p><p><b>CONCLUSIONS</b>Disbalance of CD(4)(+) T lymphocytes subsets and increases in quantity and IFN-gamma producing function of Th1 cells might be important for the development of bone marrow failure in AA and in distinguishing AA from other kinds of pancytopenic diseases.</p>
Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Anemia, Aplastic , Blood , Colony-Forming Units Assay , Erythroid Precursor Cells , Cell Biology , Granulocytes , Cell Biology , Hematopoietic Stem Cells , Cell Biology , Interferon-gamma , Genetics , Interleukin-4 , Genetics , Macrophages , Cell Biology , RNA, Messenger , Genetics , Metabolism , Th1 Cells , Cell Biology , Metabolism , Physiology , Th2 Cells , Cell Biology , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To study the in vitro effects of low-molecular weight heparin (LMWH) and dexamethasone on the hemolysis of red blood cells from paroxysmal nocturnal hemoglobinuria (PNH) patients.</p><p><b>METHODS</b>By Ham's test and micro-complement lysis sensitive test (mCLST), the changes of hemolysis of red blood cells from 6 PNH patients were tested by adding different doses of LMWH and dexamethasone into the test mixture. The effects of LMWH and dexamethasone on the coagulation of the tested blood samples were also studied by activated partial thromboplastin time (APTT).</p><p><b>RESULTS</b>(1) Either LMWH or dexamethasone could dose-dependently inhibit the hemolysis of PNH red blood cells, and the effects were synergistic when added together. The same dose of LMWH induced a less than 100% prolongation of APTT. (2) Dexamethasone could inhibit the hemolysis in Ham's test and had different effects on the hemolysis by different adding methods in mCLST. LMWH could inhibit the hemolysis in both Ham's test and mCLST.</p><p><b>CONCLUSION</b>Both LMWH and dexamethasone could inhibit the hemolysis of PNH red cells and showed a synergistic effect. The mechanisms of the inhibition of hemolysis were different. Furthermore, a tolerable dose of LMWH induced only a limited prolongation of APTT, which might be useful for controlling acute hemolysis and reducing the dose of dexamethasone.</p>