CD11a antibody targets the CD11a subunit, a key component of the integrin family, specifically the lymphocyte function-associated antigen-1 (LFA-1). LFA-1. a heterodimer of CD11a and CD18. is expressed on leukocytes and mediates cell-cell adhesion by binding to intercellular adhesion molecule-1 (ICAM-1). This interaction is critical for immune processes like T-cell activation, leukocyte migration, and immune synapse formation. CD11a antibodies block LFA-1/ICAM-1 binding, suppressing inflammatory responses.
Therapeutic CD11a antibodies, such as efalizumab, were developed for autoimmune diseases like psoriasis. Efalizumab demonstrated efficacy by inhibiting T-cell trafficking and activation but was withdrawn due to rare cases of progressive multifocal leukoencephalopathy (PML) linked to immunosuppression. Despite this, CD11a remains a research focus for immune modulation.
In research, CD11a antibodies are tools to study leukocyte adhesion mechanisms, immune cell interactions, and inflammatory disease models. They help elucidate pathways in transplant rejection, autoimmunity, and cancer immunotherapy. Their dual role as therapeutic agents and experimental reagents underscores their importance in immunology and drug development.