Organ damage occurs in up to 70 percent of patients in the first months after stem cell transplantation. The precise reasons for this potentially fatal reaction have long been the subject of scientific research. Researchers led by Georg Stary from the Dermatology Department of MedUni Vienna and the Vienna General Hospital in collaboration with the Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases have recently identified bacterial proliferation in the skin as a factor associated with the appearance of the complication. The findings recently published in the medical journal “Leukemia” contribute to the research and development of new therapeutic approaches.
The researchers reached their findings by examining the skin of 50 patients, most of whom had undergone stem cell transplantation (SCT) for leukemia at the Department of Internal Medicine’s Department of Bone Marrow Transplantation And from MedUni Vienna and the Vienna General Hospital. In the first weeks or months after receiving the donor stem cells, a donor-to-recipient reaction (graft-versus-host disease, GVHD) occurred in some of the test subjects. When the microorganisms on the skin (skin microbiome) of those affected were analyzed in detail, the research team led by first author Nadine Bayer and study leader Georg Stary from MedUni Vienna and the General Hospital of Vienna found a drastic decrease in bacterial abundance. “The reduction in proliferation was particularly pronounced in severe cases of GVHD, even before symptoms appeared,” Georg Stary reported on the key findings. At the same time, scientists observed an increase in the appearance of staphylococci on the skin in patients with GVHD, that is, bacteria that can cause serious infections.
The reaction almost always involves the skin
Despite careful examinations of the tissue characteristics of stem cell donors and recipients, as well as preventive medication, GVHD occurs in approximately 30% of patients after sibling donations and in approximately 70% of patients after donations from unrelated donors. This reaction means that the body’s cells are attacked as foreign by immune cells that have recently developed from the transplant, and the organs are subsequently damaged. The complication almost always affects the skin: the first symptoms are usually skin rashes, which, depending on the severity, can manifest as mild redness or very inflamed skin changes with detachment of the top layer of skin.
The fact that the composition of the gut microbiome influences the clinical course after stem cell transplantation was already known to medical researchers. With the identification of the skin microbiome in GVHD, scientists have another tool at their disposal to research and develop improved treatment measures.
Follow-up studies will now show whether the change in the skin microbiome can contribute to the development of GVHD and whether new therapeutic approaches can be identified based on the knowledge gained.”
Georg Stary, head of study
Georg Stary also works at the CeMM Molecular Medicine Research Center of the Austrian Academy of Sciences and the Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, with an eye towards the future.
Source:
Medical University of Vienna
Journal reference:
Bayer, N., et al. (2022) Alterations in skin microbial recolonization and cutaneous immune response after allogeneic stem cell transfer. leukemia doi.org/10.1038/s41375-022-01712-z.