CD9 influence on CHO cell adhesion to FN and pericellular FN matrix assembly is reversed by CD9 EC2 deletion mutant Δ173-192, Δ152-192, and Δ133-192 expression.
(A) MOCK, A6, and CD9 deletion mutants Δ173-192, Δ152-192, and Δ133-192 CHO cells were allowed to adhere to FN, as described in “Materials and methods.” After stringent washing, adherent cells were counted in 5 high-power (× 40) fields of view/well from 3 wells per assay and reported as the number of adherent cells/mm2. Data are expressed as the means ± SEs of 3 independent assays. All deletion mutants had adhesive phenotypes comparable to the CHO MOCK cells. (B) MOCK, A6, and CD9 EC2 deletion mutants Δ173-192, Δ152-192, Δ133-192, and Δ113-228 CHO cells were grown to 100% confluency in the presence of bovine plasma FN. Immunofluorescent images revealed that partial (Δ173-192, Δ152-192, and Δ133-192) or complete (Δ113-228) EC2 deletions restored the pericellular FN matrix assembly as effectively to that observed with MOCK CHO cells. Original magnification × 25.
