To assess whether the major histocompatibility complex (MHC) profile of patients presenting with primary antiphospholipid syndrome (PAPS) is different from that of patients with secondary antiphospholipid syndrome (SAPS), we studied 123 patients, 34 of whom presented PAPS and 35 SAPS due to systemic lupus erythematosus (SLE), 54 SLE patients without antiphospholipid syndrome (APS), and 166 controls. HLA-DRB1 and DQB1 alleles were typed using amplified DNA hybridized with sequence-specific primers. Compared to controls, PAPS patients exhibited a nonsignificantly increased frequency of DR53-associated alleles, and SAPS patients presented an increased frequency of HLA-DRB1*03 alleles (corrected P = 0.05). In addition, HLA-DRB1*03 alleles were over-represented in SAPS patients presenting anticardiolipin antibody (aCL) (Pc = 0.02), in SLE patients as a whole (Pc < 0.0001), and in SLE patients without APS (Pc = 0.02). The frequency of aCL among SLE patients presenting or not HLA-DRB1*03 alleles was closely similar. A trend to an increase in the frequency of the DQB1*0604 allele (14.3 versus 4.2%, P = 0.03) and of the DQB1*0302 allele (31.4 versus 12.7%, P = 0.01) was observed in SAPS. Taken together, these results indicate that the association of SAPS with HLA-DRB1*03 is due to the association with SLE and is not due to aCL, and suggest that the HLA class II profile of PAPS is different from that of SAPS.

The systemic oxidative status in hypertensives disorders of pregnancy (HDP) and its association with endothelial dysfunction is controversial. In the present study, we evaluated systemic plasma levels of oxidative stress markers (TBARS (thiobarbituric acid-reactive substances) and carbonyl) and total antioxidant status (FRAP (ferric reducing ability of plasma (ferric reducing/antioxidant power) and reduction of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide))), as well as assessed the impact these markers have on nitric oxide (NO) status in healthy pregnant (HP, n=38), gestational hypertensive (GH, n=33) and preeclamptic pregnant women (PE, n=28). We found similar values of TBARS among all groups, and reduced carbonyl levels in HDP between the PE and GH. Conversely, significant increases in plasma activity of antioxidant status were observed in the GH and PE groups compared to the HP group (using both MTT or FRAP method). Importantly, HDP present significantly lower nitrite levels compared to HP women. In Conclusion, our findings show a compensatory antioxidant mechanism against reactive oxygen species (ROS) generation in HDP, which is not associated with nitrite levels restoration.

Lymphocytotoxic antibodies occurred more frequently in patients with active SLE than in patients with inactive disease, irrespective of the presence of NP manifestations, a finding that is similar to classical biomarkers of lupus activity (anti-dsDNA and complement). These results indicate that the assessment of the presence of lymphocytotoxic antibodies may be an additional useful tool for the evaluation of SLE activity.