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.