Related Experiment Videos

Progressive depletion of peripheral B lymphocytes in 4-1BB (CD137) ligand/I-Ealpha)-transgenic mice

G Zhu1, D B Flies, K Tamada

  • 1Department of Immunology, Mayo Graduate and Medical Schools, Mayo Clinic, Rochester, MN 55905, USA.

Interaction of 4-1BB (CD137) and its ligand (4-1BBL) is thought to positively regulate cell-mediated and humoral immune responses. We have prepared transgenic mouse strains that express 4-1BBL cDNA under the control of MHC class II I-Ealpha promoter. The 4-1BBL-transgenic mice show progressive splenomegaly and selective depletion of B220(+) B cells accompanied with low levels of circulating IgG and defective humoral responses to Ag challenge. In addition, splenocytes from the transgenic mice fail to provide stimulation for allogeneic T cells in both lymphoproliferative and CTL responses in vitro, whereas their T cells remain functionally normal. Our results reveal unexpected functions of 4-1BBL in the regulation of humoral immune responses and Ag presentation.

Related Concept Videos