[Diagnosis and management of chronic renal failure in the elderly]. / Diagnostic et prise en charge de l'insuffisance rénale chronique chez la personne âgée.

The incidence of chronic renal failure in the elderly is rising due to the ageing of the general population. Its management, and notably nephroprotective therapies, must be adapted to the elderly person who is often frail and with multiple pathologies. The decision to start extra-renal purification does not depend on the patient's chronological age but on their physiological age and requires dialogue between the patient and their family, the geriatrician and the nephrologist.

B cells display an abnormal distribution and an impaired suppressive function in patients with chronic antibody-mediated rejection.

In kidney transplantation, the composition of the B-cell compartment is increasingly identified as an important determinant for graft outcome. Whereas naive and transitional B cells have been associated with long-term allograft survival and operational tolerance, memory B cells have been linked to graft rejection and graft loss. Chronic antibody-mediated rejection now represents a major complication in transplantation and is a challenge in current therapeutics. Here, we show that patients with chronic antibody-mediated rejection display a unique B-cell phenotype with a reduced ratio of activated to memory B cells associated with an impaired immunosuppressive activity. The regulatory functions of the B cells depended on their maturation status. Thus, phenotypic and functional analyses of the B-cell compartment may be indicated for appropriate follow-up after transplantation and drive therapy in the establishment of transplant tolerance processes.

A case for the graft-versus-host disease as a model for B cell-mediated autoimmunity.

Following allogenic hematopoietic stem cell transplantation (HSCT), patients with autoimmune disease or hematopoietic malignancy may develop acute or chronic graft-versus-host (GvH) disease. B lymphocytes, from the recipient as well as from the donor, have recently been implicated in the pathogenesis of such disturbances. Their deleterious effects are accounted for by other tasks B lymphocytes accomplish than the antibody production. We highlight herein some recent observations in the context of B cells in the GvH disease.

Glomerular antibodies in lupus nephritis.

Lupus nephritis (LN) remains the most common severe manifestation of systemic lupus erythematosus (SLE) characterized by the presence of autoantibodies (Abs) that are believed to play a central role in the pathogenesis of LN. Among more than 100 Abs reported in SLE, only a few display a direct glomerular binding capacity. Such antiglomerular Abs are detected at the onset of the disease before antinuclear Abs detection and proteinuria, this detection is associated with the related autoantigen overexpression. Antiglomerular Abs are able to interfere with cell metabolism, to penetrate living cells, and to induce glomerular cell proliferation. In addition, antiglomerular Abs could be nephritogenic causing proteinuria, particularly when they cross-react with anti-dsDNA Abs. Antiglomerular Abs encompass anti-α-actinin, anti-laminin-1, antifibronectin, antimyosin, and anticollagen Abs. The pathogenic activity of anti-α-actinin Abs has been demonstrated in non-autoimmune mice after immunization with α-actinin, but not with dsDNA, leading to a SLE-like disease with proteinuria and glomerular immune complex deposition. Similarly, extracorporeal immunoabsorption to remove anti-laminin-1 Abs reduces kidney-Abs deposition and proteinuria in mice and humans proving their pathogenic effect. Altogether this suggests that antiglomerular Abs participate, at least at the beginning, in the glomerular immune complex deposition and in the kidney damage.