Mucous membrane pemphigoid following reduced intensity conditioning allogeneic haematopoietic SCT for biphenotypic leukaemia

Humoral Epitope Spreading in Autoimmune Bullous Diseases

Autoimmune blistering diseases are characterized by autoantibodies against structural adhesion proteins of the skin and mucous membranes. Extensive characterization of their autoantibody targets has improved understanding of pathogenesis and laid the basis for the study of antigens/epitopes diversification, a process termed epitope spreading (ES). In this review, we have reported and discussed ES phenomena in autoimmune bullous diseases and underlined their functional role in disease pathogenesis. A functional ES has been proposed: (1) in bullous pemphigoid patients and correlates with the initial phase of the disease, (2) in pemphigus vulgaris patients with mucosal involvement during the clinical transition to a mucocutaneous form, (3) in endemic pemphigus foliaceus, underlining its role in disease pathogenesis, and (4) in numerous cases of disease transition associated with an intermolecular diversification of immune response. All these findings could give useful information to better understand autoimmune disease pathogenesis and to design antigen/epitope specific therapeutic approaches.

Immune processes and pathogenic fibrosis in ocular chronic graft-versus-host disease and clinical manifestations after allogeneic hematopoietic stem cell transplantation

Activation of the immune system and progressive fibrosis are prominent features of chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation. The main histologic findings in affected exocrine glands are marked fibrosis of the interstitium and prominent increase in the number of fibroblasts, accompanied by mild lymphocytic infiltration. Clinically, the severity of dry eye is correlated with the degree of fibrotic changes, rather than with the amount of lymphocytic infiltration, indicating that excessive extracellular matrix accumulation primarily contributes to the exocrine dysfunction. We have found that accumulated fibroblasts in the lacrimal gland of patients with cGVHD have a chimeric status. Thus, fibroblasts originating from circulating donor-derived precursors and recipient-derived fibroblasts by local epithelial mesenchymal transition may participate in the excessive fibrosis in patients with cGVHD by interacting with T cells. In this article, the immune response and pathogenic fibrosis in ocular cGVHD will be discussed. In addition, clinical findings of ocular complications after hematopoietic stem cell transplantation and currently available treatment will also be discussed.