Skin explant model assay predicts the incidence and the severity of acute graft versus host disease before allogeneic haematopoietic cell transplantation. The method is used for selection of donors and planning of optimal GvHD prophylaxis.
In the present pilot study the authors use skin explant model assay for evaluation of the disease activity in patients with rheumatoid arthritis (RA) and juvenile chronic arthritis (JCA). The method is based on evaluation of histopathological changes in patient's skin explant caused by patient's immunocompetent cells sensitised first in autologous mixed lymphocyte culture (MLC) or without previous sensitisation.
Histopathological changes are evaluated according to the standard Lerner classification for acute GvHD and reflect the degree of disease activity. The authors tested a total of 12 patients with RA/JCA.
No or only insignificant histopathological changes were found (grade 0-II) in patients in remission or with a slight activity of the disease. Patients with refractory, long-lasting active disease had severe histopathological changes of grade III-IV in their skin explants.
Based on the results of this pilot study it is obvious that the skin explant model assay could be useful for evaluation of activity or progression of the disease and response to treatment. With regard to hitherto achieved results in patients with RA/JCA the authors are testing skin explant model assay as a tool for detection of the activity of the autoimmune process also in other systemic autoimmune diseases.