Systemic lupus erythematosus (SLE) is an autoimmune disease affecting many organs and tissues of the body. In autoimmune diseases, the patient's own immune system that is designed to neutralize foreign substances and microorganisms reacts with proteins found in the body's tissues. In SLE, B lymphocytes secrete antibodies that react and attach to various antigens circulating in blood. The antibody and antigen form immune complexes that can deposit in several types of tissues, such as blood vessels, blood cells, kidneys and skin. Deposited immune complexes attract inflammatory cells and activate the complementary pathway to cause an inflammatory reaction.
Cause and Manifestations of SLE
The manifestations of systemic lupus erythematosus are generally due to inflammation in areas where immune complexes are deposited. If you have SLE, the most common symptoms you could experience are fever, skin rashes and joint pains, especially if you are of childbearing age. However, because SLE is a systemic disease, it has a long list of possible manifestations, including oral ulcers, anemia, blood and protein in urine, and neurological and psychiatric disturbances.
The cause of SLE is still unclear, although it is probably due to a combination of genetic, environmental and hormonal factors that ultimately cause the production of autoantibodies. Among the causative factors implicated are particular human leukocyte antigen (HLA) genes are environmental and occupational exposure to drugs, silica, pesticides, mercury and sunlight, and also estrogen.
Blood is generally composed of two main parts: a cellular layer composed of white and red blood cells and platelets, and a liquid layer called plasma. Plasma is essentially water with varying amounts of dissolved salts and proteins. Generally speaking, plasmapheresis is the process whereby plasma is separated from, treated and then finally returned to the blood.
During the procedure, blood is taken out of the body through a needle or a catheter. The blood is run through a cell separator that uses either a centrifuge or a hemodialysis-like filter to separate plasma from the red blood cells. Separated plasma is further treated to remove certain antibodies, while red blood cells are immediately returned to the body. Ultimately, treated plasma is returned to the body.
Role of Plasmapheresis in SLE Treatment
One of the most important clinical uses of plasmapheresis is the rapid removal of antibodies from the circulation in the treatment of autoimmune diseases like SLE. The production of autoantibodies–examples of which are antinuclear antibody (ANA), anti-Sm and anti-dsDNA–lies at the core of the pathophysiology of systemic lupus erythematosus.
The removal of these autoantibodies via plasmapheresis is an effective treatment for severe or progressive cases of systemic lupus erythematosus, especially those cases that already have extensive brain or kidney involvement. However, plasmapheresis should not be viewed as a definitive cure, but only as a short-term treatment that arrests or slows down the progression of the disease.
While plasmapheresis can remove circulating autoantibodies, it cannot inhibit their production. UItimately, plasmapheresis should be augmented by therapies that will also suppress the production of autoantibodies. Plasmapheresis is combined with immunosuppressants and immunomodulators such as steroids, cyclophosphamide, cyclosporine or mycophenolate mofetil.