The CD57+ cells document the extent of the immune suppression of chronic Lyme disease. Based on the current literature, CD57+ cells are a prognostic laboratory parameter during and after the treatment of chronic Lyme disease.
Clinical research studies and case studies have shown that chronic Lyme infections are often accompanied by changes in the cellular immune defense. Evidence for this is a decreased number of the Natural Killer-cells (NK/CD3-CD56+), but particularly a decreased absolute number of the activated NK-cells (CD3-CD56+CD57+). While acute Borrelia burgdorferi infections and other diseases show normal CD57-parameters, chronic Lyme patients often have less than 100 CD57-cells/µl.
According to scientific studies, a suppressed absolute number of CD57-cells has been mainly observed in patients whose nervous system has been affected rather than in patients whose tissue or skeleton system has been affected. The decrease of CD57 cells lasts until improvements in symptoms are achieved due to antibiotic and other treatment forms. In reverse, a decreased CD57 parameter is seen as a measurable signal for an active chronic Borrelia infection and can be a possible indicator for a successful therapy.
The elderly and patients with underlying medical problems such as high blood pressure, cardiac issues, diabetes, cancer, another active infection and/or those with immunosuppression are more likely to suffer from more severe symptoms from COVID-19 ,,,.
In suspected cases we therefore recommend additional testing of the innate (CD3+) and natural killer cells (CD56+/CD57+).
The identification of CD3+/CD56+/CD57+ NK cells indicators:
Lymphocytes develop from precursor cells located in the bone marrow. B-cells (bone marrow) and natural killer cells (NK) migrate from there directly to the periphery. T cells (thymus), on the other hand, migrate from the bone marrow into the thymus, where they undergo positive and negative selection. They develop into naive T cells that have not yet had antigen contact and patrol between blood and lymphatic tissues. Natural killer T-cells are another T-cell line that develops in the thymus and has another receptor besides the T-cell receptor that recognises glycolipid antigens of bacterial origin.
T cells (CD3+ lymphocytes) recognize antigens by means of their T cell receptor and the cofactor CD3 and induce or regulate the innate immune defense. T cells are increased in viral (e.g. rubella) and bacterial (in the overcoming phase) infections as well as fungal infections (e.g. pneumocystis, candida), typhoid, T-cell leukemia and lymphomas and in smokers. Reduced T-cells are found in congenital (DiGeorge syndrome, SCID, Wiskott-Aldrich syndrome, Ataxia teleangiektasia/LouisBar syndrome) and acquired (malignant diseases, infectious diseases, e.g. AIDS, tuberculosis), immune defects, after radiation and medication with immunsuppressants (e.g. e.g. glucocorticoids), cytostatics or steroids, in chronic liver diseases (e.g. liver cirrhosis, alcohol-related and non-alcohol-related steatohepatitis, hepatitis C), burns, SLE and other autoimmune diseases, Cushing's syndrome, renal failure and iron deficiency anemia.
Natural killer cells (NK cells, CD3+/CD16+/CD56+/CD57+) are effector cells of the innate immune system. They kill tumour cells and virus-infected body cells by triggering their apoptosis. Elevated NK cells are found in viral infections, mycoplasma infections or after drug-related immune stimulation as well as in NK cell leukaemia (rare). Decreased NK cells are found in progressive tumour growth, in smokers, during physical exercise and during a low-calorie diet.
CD57+ cells as a subset of NK cells can be increased in chronic viral infections with e.g. CMV, HIV, Hepatitis C, Epstein Barr virus.
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