MAb 5261-muIg-mediated inhibition of B cell migration into the spleens of naïve BALB/c mice. Recipient mice were treated with 30 mg/kg of an Isotype Control Ab or MAb 5261-muIg intraperitoneally twice a week for 2 weeks before adoptive transfer of CFSE-labeled donor B cells (2x107 cells per mouse; i.v.). (A) Percentage of CFSE+ B cells in mouse spleens (n = 3/group) as measured by flow cytometry. Flow data were analyzed using FlowJo 7.6 software. Statistical significance was evaluated using unpaired Student’s t-test (B) IHC on representative spleen sections where CFSE-labeled adoptively transferred cells are green and B cells are labeled red.