Molecular attributes of conjugate antigen influence function of antibodies induced by anti-nicotine vaccine in mice and non-human primates.
Anti-nicotine vaccines aim to prevent nicotine entering the brain, and thus reduce or eliminate the reward that drives nicotine addiction. Those tested in humans to date have failed to improve quit rates over placebo, possibly because antibody (Ab) responses were insufficient to sequester enough nicotine in the blood in the majority of subjects. We have previously shown in mice that the carrier, hapten and linker used in the nicotine conjugate antigen each influence the function (nicotine-binding capacity) of the Ab induced. Herein we have evaluated immunogenicity in mice of 27 lots of NIC7-CRM, a conjugate of 5-aminoethoxy-nicotine (Hapten 7) and a mutant nontoxic form of diphtheria toxin (CRM197), that differed in three antigen attributes, namely hapten load (number of haptens conjugated to each molecule of CRM197), degree of conjugate aggregation and presence of adducts (small molecules attached to CRM197 via a covalent bond during the conjugation process). A range of functional responses (reduced nicotine in the brain of immunized animals relative to non-immunized controls) were obtained with the different conjugates, which were adjuvanted with aluminum hydroxide and CpG TLR9 agonist. Trends for better functional responses in mice were obtained with conjugates having a hapten load of 11 to 18, a low level of high molecular mass species (HMMS) (i.e., not aggregated) and a low level of adducts and a more limited testing in cynomolgus monkeys confirmed these results. Thus hapten load, conjugate aggregation and presence of adducts are key antigen attributes that can influence Ab function induced by NIC7-CRM.
Pfizer Vaccine Immunotherapeutics, Ottawa Laboratories, Ottawa, Ontario, Canada. Electronic address: michael.mccluskie@pfizer.com.
Michael J
MJ
McCluskie
Pfizer Biotherapeutics Pharmaceutical Sciences, St. Louis, MO, USA.
Jennifer
J
Thorn
Pfizer Biotherapeutics Pharmaceutical Sciences, St. Louis, MO, USA.
Paul R
PR
Mehelic
Pfizer Biotherapeutics Pharmaceutical Sciences, St. Louis, MO, USA.
Parag
P
Kolhe
Pfizer Biotherapeutics Pharmaceutical Sciences, St. Louis, MO, USA.
Keshab
K
Bhattacharya
Pfizer Biotherapeutics Pharmaceutical Sciences, St. Louis, MO, USA.
Jari I
JI
Finneman
Pfizer Vaccine Immunotherapeutics, La Jolla, CA, USA.
David R
DR
Stead
Pfizer Biotherapeutics Pharmaceutical Sciences, St. Louis, MO, USA.
Michele Bailey
MB
Piatchek
Pfizer Vaccine Immunotherapeutics, Ottawa Laboratories, Ottawa, Ontario, Canada.
Ningli
N
Zhang
Pfizer Vaccine Immunotherapeutics, Ottawa Laboratories, Ottawa, Ontario, Canada.
Ghania
G
Chikh
Pfizer Vaccine Immunotherapeutics, Ottawa Laboratories, Ottawa, Ontario, Canada.
Janna
J
Cartier
Pfizer Vaccine Immunotherapeutics, Ottawa Laboratories, Ottawa, Ontario, Canada.
Dana M
DM
Evans
Pfizer Vaccine Immunotherapeutics, La Jolla, CA, USA.
James R
JR
Merson
Pfizer Vaccine Immunotherapeutics, Ottawa Laboratories, Ottawa, Ontario, Canada.
Heather L
HL
Davis
D000818:Animals; D000915:Antibody Affinity; D000941:Antigens / Q000737:chemistry / Q000276:immunology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000276:immunology*; D001921:Brain / Q000378:metabolism; D005260:Female; D006241:Haptens / Q000737:chemistry / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008252:Macaca fascicularis; D008807:Mice, Inbred BALB C; D009538:Nicotine / Q000097:blood / Q000276:immunology* / Q000493:pharmacokinetics; D014029:Tobacco Use Disorder / Q000628:therapy; D014612:Vaccines
D000941:Antigens; D001426:Bacterial Proteins; D006241:Haptens; D007074:Immunoglobulin G; D014612:Vaccines; C448865:hapten 7; C028581:CRM197 (non-toxic variant of diphtheria toxin); D009538:Nicotine
Anti-nicotine vaccine; Conjugate vaccine; Nicotine addiction; Smoking cessation