A CD28 superagonistic antibody elicits 2 functionally distinct waves of T cell activation in rats.
Administration of the CD28 superagonistic antibody JJ316 is an efficient means to treat autoimmune diseases in rats, but the humanized antibody TGN1412 caused devastating side effects in healthy volunteers during a clinical trial. Here we show that JJ316 treatment of rats induced a dramatic redistribution of T lymphocytes from the periphery to the secondary lymphoid organs, resulting in severe T lymphopenia. Live imaging of secondary lymphoid organs revealed that JJ316 administration almost instantaneously (<2 minutes) arrested T cells in situ. This reduction in T cell motility was accompanied by profound cytoskeletal rearrangements and increased cell size. In addition, surface expression of lymphocyte function-associated antigen-1 was enhanced, endothelial differentiation sphingolipid G protein-coupled receptor 1 and L selectin levels were downregulated, and the cells lost their responsiveness to sphingosine 1-phosphate-directed migration. These proadhesive alterations were accompanied by signs of strong activation, including upregulation of CD25, CD69, CD134, and proinflammatory mediators. However, this did not lead to a cytokine storm similar to the clinical trial. While most of the early changes disappeared within 48 hours, we observed that CD4+CD25+FoxP3+ regulatory T cells experienced a second phase of activation, which resulted in massive cell enlargement, extensive polarization, and increased motility. These data suggest that CD28 superagonists elicit 2 qualitatively distinct waves of activation.
Müller
Nora
N
Institute for Virology and Immunobiology, University of Wuerzburg, Wuerzburg, Germany.
van den Brandt
Jens
J
Odoardi
Francesca
F
Tischner
Denise
D
Herath
Judith
J
Flügel
Alexander
A
Reichardt
Holger M
HM
D000818:Animals; D000906:Antibodies / Q000008:administration & dosage / Q000276:immunology*; D015415:Biomarkers; D018106:CD28 Antigens / Q000276:immunology*; D002448:Cell Adhesion / Q000187:drug effects / Q000276:immunology; D002465:Cell Movement; D016764:Cell Polarity / Q000276:immunology; D002470:Cell Survival; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D003599:Cytoskeleton / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D008221:Lymphoid Tissue / Q000276:immunology; D008231:Lymphopenia / Q000139:chemically induced / Q000276:immunology / Q000473:pathology; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D013997:Time Factors; D015854:Up-Regulation
D000906:Antibodies; D015415:Biomarkers; D018106:CD28 Antigens; D016207:Cytokines