Anti-endothelial antibodies and neuropsychiatric systemic lupus erythematosus.

The pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) has been attributed to autoantibody-mediated neural dysfunction, vasculopathy, and coagulopathy. Several autoantibodies specificities have been reported in serum and cerebrospinal fluid of NPSLE patients (i.e., antineuronal, antiribosomal P proteins, antiglial fibrillary acidic proteins, antiphospholipid, and anti-endothelial antibodies). We have recently demonstrated an association between serum anti-endothelial antibodies and psychosis or depression in patients with SLE. Subsequently, by screening a cDNA library from human umbilical artery endothelial cells with serum from a SLE patient with psychosis, one positive strongly reactive clone was identified encoding the C-terminal region (C-ter) of Nedd5, an intracytoplasmatic protein of the septin family. Anti-Nedd5 antibodies have been found significantly associated with psychiatric manifestations in SLE patients, strengthening the view of a possible implication of autoantibodies in the development of psychiatric disorders.

CD34-positive cells in human umbilical cord blood express nerve growth factor and its specific receptor TrkA.

In this study, we investigated whether hematopoietic stem cells (HSC) and progenitors present in human cord blood can express nerve growth factor (NGF)-specific receptors, TrkA and p75. Our results showed a marked expression of TrkA and NGF in cord blood CD34(+) cells. A gradient of TrkA and NGF expression exists and is highest in cord blood CD34(+) cells, reduced in cord blood mononuclear cells (MNC) and minimal in mononuclear cells isolated from adult peripheral blood. Our findings suggest that NGF may play a role in the differentiation of hematopoietic progenitors and indicate a different requirement for NGF by immune cells, depending on their state of maturity.