Understanding the Role of LFA-1 in Leukocyte Adhesion Deficiency Type I (LAD I): Moving towards Inflammation?

LFA-1 (Lymphocyte function-associated antigen-1) is a heterodimeric Integrin (CD11a/CD18) present on the surface of all leukocytes; it is essential for leukocyte recruitment to the site of tissue inflammation, but also for Other immunological processes such as T cell activation and formation of the immunological synapse. Absent or dysfunctional expression of LFA-1, caused by mutations in the ITGB2 (Integrin subunit beta 2) gene, results in a rare immunodeficiency syndrome known as Leukocyte adhesion deficiency type I (LAD I). Patients suffering from severe LAD I present with recurrent infections of the skin and mucosa, as well as inflammatory symptoms complicating the clinical course of the disease before and after allogeneic hematopoietic stem cell transplantation (alloHSCT); alloHSCT is currently the only established curative treatment option. With this review, we aim to provide an overview of the intrinsic role of inflammation in LAD I.

hematopoietic stem cell transplantation; inborn errors of immunity; inflammation.