• CD49c is a 150 kD α integrin chain known as α3 integrin or VLA-3 α chain. It is a type I transmembrane glycoprotein which is proteolytically cleaved into two disulfide linked fragments of 125 kD and 30 kD. CD49c forms a heterodimer with integrin β1 (α3β1, CD49c/CD29, VLA-3) and is expressed by many types of adhesion cells, such as endothelial cells, epithelial cells, and dermal fibroblasts. Weak expression has been reported on leukocytes. VLA-3 plays a role in cell-cell and cell-matrix adhesion through binding Kalinin, collagen, laminin-1, laminin-5, entactin, and fibronectin.
• The exons 1~23 of mouse Itga3 gene that encode the full-length protein were replaced by human ITGA3 exons 1~26 in B-hITGA3 mice. 
• Human ITGA3 protein was detectable in endothelial cells and epithelial cells of homozygous B-hITGA3 mice, but not in wild-type mice. Mouse Itga3 mRNA was only detectable in wild-type mice. Human ITGA3 mRNA was exclusively detectable in homozygous B-hITGA3 mice but not in wild-type mice. 

Strain specific analysis of ITGA3 mRNA expression in wild-type C57BL/6JNifdc mice and homozygous B-hITGA3 mice by RT-PCR. Lung RNA were isolated from wild-type C57BL/6JNifdc mice (+/+) and homozygous B-hITGA3 mice (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse or human ITGA3 primers. Mouse Itga3 mRNA was only detectable in wild-type mice. Human ITGA3 mRNA was exclusively detectable in homozygous B-hITGA3 mice but not in wild-type mice. 

Strain specific ITGA3 expression analysis in wild-type C57BL/6JNifdc and homozygous B-hITGA3 mice by flow cytometry. Lung cells were collected from wild-type C57BL/6JNifdc (+/+) and homozygous B-hITGA3 mice (H/H) and analyzed by flow cytometry with strain specific anti-hITGA3 antibody（Biolegend, 343808). Human ITGA3 was detectable in endothelial cells and epithelial cells of homozygous B-hITGA3 mice but not in wild-type mice.