GLOSSARY

O

• OT-I transgenic mice and T cells #

  A transgenic mouse line created to contain the OVA-specific CD8⁺ T cell receptor from the H2-Kb-restricted OVA257-254 (SIINFEKL)-specific CTL clone 149.42 (Kelly et al., 1993) (originally called OVA-tcr-II mice). cDNAs encoding the complete 149.42 α-chain and the genomic β-chain construct, pKS913.CB16.31 (Carbone et al., 1992) were co-injected into blastocysts from (B6 x bm1) Fl mice and progeny of the founder line, 243-2, were backcrossed to B6 mice. OT-1 mice, their naive- or antigen-stimulated T cells, and derivatives have been used extensively to study MHC-I-restricted T cell development and selection, immune tolerance, autoimmune disorders, and antitumor immune responses.

• OT-II transgenic mice and T cells #

  A transgenic mouse line engineered to express CD4⁺ T cells that express an OVA-specific αβ TCR. The TCR cDNAs were cloned from T cell hybridoma, Clone 1.1, which was derived from a C57BL/6 (B6) mouse primed with whole ovalbumin in Complete Freund’s Adjuvant. Clone 1.1 is CD4⁺, MHC-II I-Ab-restricted, and specific for the OVA323-339 peptide. The TCR beta chain is expressed under the control of its natural regulatory elements to successfully generate mice that express the introduced TCR in peripheral T cells and respond to the OVA antigen (Barnden et al., 1998). OT-II mice, their naive- or antigen-stimulated T cells, and derivatives have been used extensively to study MHC-II-restricted T cell development and selection, immune tolerance, autoimmune disorders, and antitumor immune responses.

• OX40L (CD252) #

  Alternative names: GP34, TNFSF4, TXGP1, CD134L

  In humans and in mice, OX40L can be found on the surface of: B cells, dendritic cells, endothelial cells

  Ligands and associated molecules: CD134 (OX40)

  Function: T cell proliferation, cytokine production, costimulation

  Additional information: OX40L is also known as CD252. CD252 belongs to the TNF superfamily and binds to CD134 (OX40), which is expressed on activated T cells. CD252–CD134 binding plays an important role in T cell proliferation and survival, promotes the formation of memory T cells, and induces polarization towards Th2. Surface expression of CD252 is upregulated in the presence of inflammatory signals. On the surface of activated B cells, CD252 enhances immunoglobulin secretion.