It can be considered the onset of rheumatoid inflammation. The formation of rheumatoid immune complexes not only determines the further destruction of the joint , but also determines the release of the pathological process beyond the joint apparatus with the appearance of systemic vasculitis. It cannot be ruled out that in a certain number of cases, it is systemic vasculitis that is the triggering factor that determines the nature of the articular lesion in the future. The nature of the damaging effect of rheumatoid immune complexes is rather complicated and is most well represented in the scheme.
The interaction of immune complexes consisting of augmented IgG and rheumatoid factors with polynuclears induces the development of inflammation. Immune complexes fix- complement, cause the formation of chemotactic factors that attract a large number of neutrophils to the site of inflammation. Neutral proteases, oxidized radicals are released from mononuclear phagocytes. Cells of synovia produce collagenase, which with lysosomal enzymes leads to degradation of cartilage. The development of bone erosion, apparently, is associated with the action of collagenase and proteoglycans.
Very important of the above pathogenesis of RA is the fact that the mechanism of damage to the joints and internal organs is an immune complex. lexing that brings it closer
disease with diffuse connective tissue diseases (systemic lupus erythematosus, systemic scleroderma, etc.) and explains certain difficulties in diagnosis and rather similar therapeutic approaches.
Currently among diverse immune complexes at RA the most theoretical and practical so value The “rheumatoid factor” (RF). The discovery of the Russian Federation is associated with the names of American doctors (Waaler (1940) and Roseu Ragan (1948) who, working with serum of RA patients, found in it a substance capable of causing agglutination of red blood cells treated with globulin. This substance was called the agglutination activating factor Or “roar is a mating factor.” The method of identifying the RF is called the Vaaler-Rose reaction, which still remains the most specific test for RA (Fig. 4).
Subsequent studies revealed a whole group of rheumatoid factors that are related to anti-immunoglobulin antibodies whose activity is directed against IgG_. They can belong to all three classes of immunoglobulins IgA, IgM, IgG. Detected using the Baaler-Rose reaction of the Russian Federation belongs to IgM, that is, it is an IgM-IgG complex.
When discussing the pathogenesis of RA, one cannot help but touch upon the question of why the synovial membrane is the target of an auto-aggressive process. To explain this for now: you can only put forward hypotheses. In particular, it is possible that joint damage at the onset of the disease reflects a general activation of the immune apparatus to an infectious stimulus. It is known that such “immune” arthritis is a frequent response in the complex of symptoms of serum sickness and in a number of infectious and allergic diseases.There is a definite explanation for this, since the synovial membrane has a morphological and functional similarity with the reticulo-endothelial system of the body. It is richly supplied with a network of capillaries and rich in lymphocytes and phagocytes. In this regard, the reaction of the synovial membrane is similar to the reaction of the reticulo-endothelial and lymphoid systems. In other words, in an infectious-allergic process, the synovial membrane “behaves” as a kind of lymph node and in RA becomes the arena and source of the immunopathological process.
It is also impossible to exclude that this is facilitated by the “arthrotropicity” of the infectious agent and the special properties of the cavity of the joints, which create conditions for long-term fixation of the lesion (this issue has already been discussed in the etiology of the disease). Finally, it is impossible not to dwell on the factors that CAN promote the development and progression of RA. In the first place here, of course, is the hormonal status of a person. One of the striking confirmations of this situation is the well-known fact of the predominant defeat of females at all ages, and especially its frequent onset in menopause. It is impossible not to recall here also the experimental work of Hans Selye, who, as far back as 1944, managed to reproduce chronic arthritis in animals, very reminiscent of RA, by administering large doses of adrenal hormones. According to the observations of therapists, the occurrence of RA and its disabilities are influenced by psychological factors among which the following are noted: loss of a spouse or a close family member; marital differences; difficulties at work; financial difficulties; extramarital sexual problems; pregnancy, abortion, childbirth, somatic diseases and a number of others.
Thus, from the current point of view, rheumatoid arthritis can be considered as a systemic disease with the obligatory development of an autoimmune process as a result of immune disregulation. The result of this process is the progression of the disease, disability due to destruction of bone tissue and the impossibility of self-healing.