Although anti-DNA antibodies have been decisively linked to the pathogenesis of lupus nephritis, the mechanisms have not been conclusively determined. Recently, we reported that anti-DNA antibodies may contribute to kidney damage by upregulation of proinflammatory genes in mesangial cells (MC), a process involving both Fc receptor-dependent and independent pathways. In investigating the mechanism by which pathogenic anti-DNA antibodies modulate gene expression in MC, we found that the pathogenic anti-DNA antibody 1A3F bound to high mobility group binding protein 1 (HMGB1), an endogenous ligand for TLR2/4 and RAGE (receptor for advanced glycation end products). Interestingly, HMGB1 treatment of MC induced a similar pattern of genes as stimulation with 1A3F. Furthermore, HMGB1 and 1A3F exhibited a synergistic proinflammatory effect in the kidney, where increased expression of HMGB1 was found in lupus patients but not in patients with other types of renal disease. TLR2/Fc and RAGE/Fc inhibited the proinflammatory effects of 1A3F on MC. Finally, we found enhanced susceptibility of lupus prone MRL-lpr/lpr (MRL/lpr) as compared to normal BALB/c derived MC to pathogenic anti-DNA antibody and LPS stimulation (in particular enhanced chemokine synthesis), in addition to significantly increased expression of TLR4. Our results suggest that gene upregulation in MC induced by nephritogenic anti-DNA antibodies is TLR2/4 and RAGE-dependent. Finally, HMGB1 may act as a proinflammatory mediator in antibody-induced kidney damage in systemic lupus erythematosus (SLE).
22q11.2 deletion syndrome (MIM: 192430/188400, ORPHA: 567) is the most common chromosomal microdeletion disorder, caused by a hemizygous microdeletion of 2.5 million base pairs on chromosome 22.
Department of Internal Medicine, Hôpital Lyon Sud, Hospices Civils de Lyon, Université Claude Bernard Lyon 1, Pierre-Bénite, France; Research on Healthcare Performance (RESHAPE), INSERM U1290, University Claude Bernard Lyon 1, 69100 Lyon, France. Electronic address:
Systemic lupus erythematosus (SLE) is an extremely heterogenous autoimmune disorder. A key biomarker, the double stranded (ds) DNA autoantibody, provides diagnostic specificity for SLE. We analyzed anti-dsDNA by mass spectrometry (MS) to determine if ascertaining the autoantibody's heavy chain variable region (IGHV) may hold any clinical relevance.
Systemic lupus erythematosus (SLE) is an autoimmune disorder that can affect various organs. Juvenile-onset SLE (jSLE) may be more severe than the adult-onset form, but the diagnosis and classification remain challenging due to the complex nature of the condition and its resemblance to other conditions. Antinuclear antibodies (ANA) are the immunological hallmark of SLE, but their limited specificity poses challenges.
Study Question: Can antinuclear antibodies (ANA) affect the subsequent live birth rate (LBR) in patients with unexplained recurrent pregnancy loss (RPL) in the absence of antiphospholipid antibodies (aPL)?
Summary Answer: Women with unexplained RPL have a high probability of live birth following a positive pregnancy test (>70%), being similar between those with positive and negative ANA testing, regardless of the cut-off value.
What Is Known Already: The RPL guidelines of the ESHRE state that 'ANA testing can be considered for explanatory purposes'. However, there have been a limited number of studies on this issue and sample sizes have been small, and the impact of ANA on the pregnancy prognosis is unclear.
