SD18 Antibody

CD18: Structure and Function

CD18 is the β subunit of the β2 integrin family, forming heterodimers with CD11a, CD11b, CD11c, or CD11d to create leukocyte adhesion molecules (e.g., LFA-1, Mac-1) . These integrins mediate:

• Cell adhesion to endothelial cells via ICAM-1 (CD54) or ICAM-2 (CD102) .

• Immune cell migration and activation during inflammation .

• Signal transduction in T cells and neutrophils .

CD18 deficiency causes leukocyte adhesion deficiency type 1 (LAD1), characterized by recurrent infections and impaired wound healing .

Clone M18/2

• Target: Mouse CD18 .

• Applications:

  • Flow cytometry (0.5 µg/test) .

  • Blocking leukocyte adhesion in functional assays .

  • Detected in splenocytes and bone marrow cells .

Clone TS1/18

• Target: Human CD18 .

• Applications:

  • Flow cytometry, immunohistochemistry, and immunocytochemistry .

  • Endotoxin levels ≤10 EU/mg .

Clone 68-5A5

• Target: Human CD18 .

• Function: Blocks LFA-1/ICAM-1 interactions .

• Reactivity: Human leukocytes .

Preclinical Studies

Clinical Trials

LIMIT AMI Trial (2001)

Mechanistic Insights

• Off-Target T Cell Activation: High-affinity CD3 bispecific antibodies (BsAbs) induce cytokine release syndrome (CRS). CD18 blockade reduces CRS risk by inhibiting LFA-1/ICAM-1 interactions without compromising antitumor activity .

• Structural Role: Only 20–33% of CDR residues directly bind antigens; non-contact residues optimize paratope conformation .

Challenges and Limitations

• Clinical Efficacy: Anti-CD18 therapies show promise in animal models but limited success in human trials (e.g., LIMIT AMI) .

• Infection Risk: Trends toward increased bacterial infections were noted with rhuMAb CD18 (p=0.33) .