Short communicationTherapeutic potential of low-dose IL-2 in a chronic GVHD patient by in vivo expansion of regulatory T cells

•Case study of a chronic GVHD patient treated with daily low-dose IL-2 therapy.•Low-dose IL-2 therapy is safe and could induce moderate clinical benefits.•Therapeutic effects of low-dose IL-2 is associated with Treg expansion in vivo.

Chronic graft-versus-host disease (cGVHD) is a common complication following allogeneic hematopoietic stem cell transplantation (HSCT), which is characterized by autoimmune like inflammatory responses and reduced levels of regulatory T cells (Tregs). Recently, the use of low-dose IL-2 has been reported to selectively increase Tregs and therefore facilitate immune regulation and promote clinical improvements in cGVHD patients. In this report, we describe the case of a cGVHD patient who was treated with daily low-dose IL-2 therapy. Our observations demonstrate that low-dose IL-2 could induce significant expansion of Tregs in vivo leading to improved Treg/Th17 ratios. The patient showed moderate clinical benefits suggesting that multiple factors may be involved in the immunological responses. Therefore, while the therapeutic potential of low-dose IL-2 is promising, strategic approaches may be needed to induce a clinically significant and sustained Treg effect.