First Promising Treatment of SLE
Last Week in Medicine
Autoimmune diseases develop when an individual’s immune cells attack their other harmless cells. Systemic lupus erythematosus (SLE) is one of these autoimmune diseases. Researchers offer a highly promising approach for the treatment of SLE.
Understanding Immune System and Immunotherapy
Two types of lymphocytes, called B and T cells, play the leading role on the basis of our immune system. These cells take their names according to their origin from the bone marrow (B cells) and thymus (T cells). We owe the discovery of these cells, which gave rise to modern immunology, to Max D. Cooper and Jacques Miller.
Speaking of SLE, it is thought that genetic or environmental causes are the reason why our immune system cells attack themselves. That’s why current treatment is done with drugs that aim to “silence” our immune system.
It is clear that these immunosuppressive treatment methods can cause unwanted side effects. This treatment method, which is logical in order for the immune system not to attack itself in a healthy state; as a result of the entry of a pathogen into the body, it causes it to be unable to attack it. Therefore, individuals become prone to diseases and are always advised to protect themselves from infectious diseases.
Finding new treatments for autoimmune diseases is essential. Different treatment methods are being tried, and one of them is immunotherapy, which I have mentioned frequently in my previous articles and which I think will have a great place in daily medical practice.
Immunotherapy has many branches and the ones we will talk about in this article are CAR T-cell therapies. T cells have receptors on them that allow them to recognize molecules other than themselves. With these receptors, T cells recognize whether that molecule is pathogenic or not, with antigens. Autoimmune diseases occur due to the disorder in this communication.
CAR T-cell therapies are almost “training” of T cells in the laboratory environment. For example, if we are developing T cells against cancer cells, we place receptors to detect cancer cell antigens on the surface of T cells in vitro. We then inject these cells back into the patients, allowing the T cells to attack the patient’s cancer cells.
This therapy method, which is still under development, has many side effects, but one of the most dangerous among them is called cytokine release syndrome (CRS). CRS is associated with the individual’s immune system being more aggressive than normal. It is a fatal condition with fever and multiorgan failure.
CAR T-cell Therapy for SLE
Mackensen et al. have published a pivotal study for the treatment of SLE in the journal Nature. They applied CAR T-cell therapy targeting the protein named CD19 on 5 patients with active SLE who could not benefit from drug treatments.
They modified the T cells in the blood taken from the patients to target CD19. After the immune cells from the patients’ bone marrow (B cells) were first eliminated (myeloablation) using cell-killing medicines, the CAR T cells were then introduced into the body. In their follow-up after 3 months, they saw that their clinical findings were subsided. Moreover, besides the regression of the active signs of the disease in the 4–16 month follow-up; they found that the effects of the disease on lung, heart and kidney tissues also disappeared.
It is stated in the study that the cytokine release syndrome we mentioned earlier did not develop, and that the therapy caused only minimal cytokine increase.
Mackensen et al. caution that, as a limitation of their study, they only tried it on 5 people, so it shouldn’t be immediately seen as a breakthrough treatment. It is also not yet known which SLE patients would benefit from this therapy.
The researchers achieved drug-free remission of SLE with their therapy. This study also serves as a precedent for my previous article on pulmonary aspergillosis, CAR T-cells for Nonmalignant Diseases.