Generation of Immunity against Pathogens via Single-Domain Antibody-Antigen Constructs.
mAbs specific for surface proteins on APCs can serve as Ag-delivery vehicles that enhance immunogenicity. The practical use of such constructs is limited by the challenge of expressing and modifying full-sized mAbs. We generated single-domain Ab fragments (VHHs) specific for class II MHC (MHCII), CD11b, and CD36. VHH sequences were modified by inclusion of a C-terminal sortase motif to allow site-specific conjugation with various Ag payloads. We tested T cell activation using VHHs that target distinct APC populations; anti-MHCII adducts elicited strong activation of CD4+T cells, whereas anti-CD11b showed CD8+T cell activation superior to targeting via MHCII and CD36. Differences in Ag presentation among constructs were unrelated to dendritic cell subtype or routing to acidic compartments. When coupled to antigenic payloads, anti-MHCII VHH primed Ab responses against GFP, ubiquitin, an OVA peptide, and the α-helix of influenza hemagglutinin's stem; the last afforded protection against influenza infection. The versatility of the VHH scaffold and sortase-mediated covalent attachment of Ags suggests their broader application to generate desirable immune responses.
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Joao N
JN
Duarte
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Juan J
JJ
Cragnolini
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Lee Kim
LK
Swee
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Angelina M
AM
Bilate
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Justin
0000-0002-0430-5165
J
Bader
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Jessica R
JR
Ingram
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Ali
A
Rashidfarrokhi
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Tao
T
Fang
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Ariën
0000-0002-5185-364X
A
Schiepers
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Leo
0000-0001-5514-2418
L
Hanke
Whitehead Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142 ploegh@wi.mit.edu.
Hidde L
0000-0002-1090-6071
HL
Ploegh
D000818:Animals; D017951:Antigen Presentation; D000936:Antigen-Antibody Complex / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology; D002161:Camelids, New World; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000502:physiology*; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000378:metabolism*; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology* / Q000517:prevention & control; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000517:prevention & control; D061905:Single-Domain Antibodies / Q000276:immunology / Q000378:metabolism*
D000936:Antigen-Antibody Complex; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D000949:Histocompatibility Antigens Class II; D007252:Influenza Vaccines; D061905:Single-Domain Antibodies