Expression of CD55 and CD59 on peripheral blood cells from systemic lupus erythematosus (SLE) patients.

CD55 and CD59 are glycosylphosphatidylinositol-anchored proteins with complement inhibitory properties. CD55 inhibits the formation of C3 convertases, and CD59 prevents the terminal polymerisation of the membrane attack complex. It has been reported that SLE patients seems to have an acquired deficiency of these proteins associated with secondary autoimmune haemolytic anaemia and lymphopenia. The aim of this study was to evaluate the presence of altered CD55 and CD59 expression on peripheral blood cells from SLE patients. Flow cytometric analyses were performed on red and white blood cells from 23 SLE patients and 23 healthy controls. We observed more CD55- and CD59-lymphocytes (p=0.005 and p=0.019, respectively), and CD59-granulocytes (p=0.045) in SLE patients than in controls. These results suggest there is an altered pattern of CD55 and CD59 expression on the peripheral blood cells of SLE patients, and it may play a role in the cytopenias in these patients.

Low bone mineral density is associated with insulin resistance in bone marrow transplant subjects.

Post-BMT subjects have an increased bone fracture risk. Additionally, several factors were associated with osteopenia and osteoporosis in these individuals. We aimed to identify other factors associated with osteopenia and osteoporosis in allogeneic post-BMT subjects. We conducted a cross-sectional study with 47 allogeneic post- BMT subjects. Serum 25-hydroxyvitamin D (25(OH)D), parathyroid hormone, ferritin, vitamin B(12), insulin, glucose, cholesterol and triglyceride levels were measured. Insulin resistance and secretion were estimated through the homeostatic model assessment for insulin resistance (HOMA-IR) and homeostatic model assessment for beta-cell function (HOMA-B), respectively. A bone densitometry (BMD) was also obtained. The median time after BMT was 47.7 (12-115) months. Osteoporosis was identified in 17.0% of the subjects and osteopenia in 19.7%. The mean serum ferritin (P=0.002), insulin (P<0.0001), glucose (P=0.003) and triglyceride (P=0.018) levels were higher in individuals with osteopenia/osteoporosis. HOMA-IR (P<0.0001) and HOMA-B (P<0.0001) were increased in post-BMT subjects with osteopenia/osteoporosis. There was no other factor associated with the outcome. After adjustments ferritin, serum 25(OH)D and HOMA-IR remained independently associated with osteopenia/osteoporosis; however triglycerides no longer were. In conclusion, in the present study, low serum 25(OH)D levels, high serum ferritin levels and insulin resistance were associated with osteopenia/osteoporosis in post-BMT subjects.