Sixty-one IRP patients, 10 severe
aplastic anemia (SAA) patients and 13 healthy controls were enrolled in this study. The categories of auto-
antibodies (
IgG,
IgM) on BMMNC (CD(34)(+)/CD(15)(+)/GlycoA(+) hematocytes), the quantity (CD(68)(+)/CD(45)(+))% and expression of
antigen activated (CD(69)) of MPhi (CD(68)(+)CD(69)(+)/CD(+)(68))% in bone marrow of all cases and controls were measured by fluorescence activated cell sorting (FACS).
RESULTS: The quantity and expression ratio of activated
antigen of bone marrow (BM) MPhi in IRP patients [(0.57 +/- 0.30)% and (40.30 +/- 18.49)%] were respectively significantly higher than those in SAA [(0.46 +/- 0.08)% and (32.44 +/- 19.37)%] and healthy controls [(0.44 +/- 0.69)% and (29.71 +/- 11.67)%] (both P < 0.05). The quantity presented high-positive correlation with the expression ratio of activated
antigen of BM MPhi (r = 0.89, P < 0.01). Patients with IRP were classified into two subgroups according to the quantity of MPhi: Group A (MPhi >/= 0.5%, 34 cases) and Group B (MPhi < 0.5%, 27 cases). Thirty-two cases (94.12%) were with auto
antibody (IgG) in Group A, while only 2 (7.41%) with auto
antibody (IgG) in Group B. There was significant difference in expression ratio of activated
antigen of BM MPhi between Group A (49.19 +/- 16.63)% and Group B (29.11 +/- 14.30)% (P < 0.05), but no difference was found between Group B and the control group (P > 0.05). Total curative rates at 3 and 6 month (47.06% and 79.41%) of Group A were better than those of Group B (22.22% and 51.85%). Thirty-four IRP patients with
autoantibody (
IgG)(+) were divided into two subgroups according to the quantity of MPhi: high level group (>/= 0.75%, 9 cases) and low level group (< 0.75%, 25 cases), 24 cases (96%) in MPhi low level group were found auto-
antibody (IgG) on one hemotopoietic cell lineage, 1 on two lineages, while 8 (88.89%) in MPhi high level group were detected auto-
antibody (IgG) on two cell lineages, and 1 on three cell lineages. Expression ratio of activated
antigen (56.12 +/- 15.11)% was much higher in MPhi high level group than that in MPhi low level group (44.58 +/- 18.16)% (P < 0.05). The count of red blood cell concentration of
hemoglobin and platelet in peripheral blood in MPhi high level group were respectively lower than those in MPhi low level group, while the percentage of Ret, the level of total
bilirubin and indirect
bilirubin, the ratio of erythroid of sternal bone marrow in MPhi high level group were higher than those in MPhi low level group.
CONCLUSION: The expression of activated
antigen of BM MPhi was enhanced in IRP especially with auto-
antibody (IgG), which might be involved in damage process of hemotopoietic cell.