Efficacy, T cell activation and antibody responses in accelerated Plasmodium falciparum sporozoite chemoprophylaxis vaccine regimens

Repeated direct venous inoculation of Plasmodium falciparum sporozoites (PfSPZ) together with antimalarial chemoprophylaxis (PfSPZ–CVac) is the most potent way to induce sterile immunity against P. falciparum infection in malaria-naive volunteers. However, established schedules are complex and long....

Full description

Saved in:
Bibliographic Details
Published in:npj vaccines 2022-05, Vol.7 (1), p.59-59, Article 59
Main Authors: Ibanez, Javier, Fendel, Rolf, Lorenz, Freia-Raphaella, Granados-Bayon, Patricia, Brückner, Sina, Esen, Meral, Sulyok, Mihály, Sulyok, Zita, Borrmann, Steffen, Bacher, Petra, Scheffold, Alexander, Hoffman, Stephen L., Kremsner, Peter G., Mordmüller, Benjamin
Format: Article
Language:English
Subjects:
631/250/590/1867
692/699/255/1629
Antibodies
Antigens
Biomedical and Life Sciences
Biomedicine
Erythrocytes
Immunogenicity
Infectious Diseases
Lymphocytes
Malaria
Medical Microbiology
Parasites
Public Health
Vaccine
Vaccines
Vector-borne diseases
Virology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Repeated direct venous inoculation of Plasmodium falciparum sporozoites (PfSPZ) together with antimalarial chemoprophylaxis (PfSPZ–CVac) is the most potent way to induce sterile immunity against P. falciparum infection in malaria-naive volunteers. However, established schedules are complex and long. Here, we tested two accelerated three-dose schedules (28- and 10-day regimen) assessing efficacy by controlled human malaria infection (CHMI) against placebo, comparing vaccine-specific T cell and antibody responses by antigen-reactive T cell enrichment (ARTE) and protein microarray, respectively. Both regimens were similarly efficacious (67 and 63% vaccine efficacy) but different in the induction of vaccine-specific T cells and antibodies. The 10-day regimen resulted in higher numbers of antigen-specific CD4+ effector memory pro-inflammatory T cells and a broader antibody response compared with the 28-day regimen. Usually in nature, P. falciparum liver stage lasts about 6.5 days. The short vaccination-interval of the 10-day regimen prolongs the time of continuous exposure to liver-stage parasites, which may explain the stronger response. Besides dose and number of vaccinations, duration of liver-stage exposure is a factor to optimize PfSPZ–CVac immunogenicity.
ISSN:2059-0105
2059-0105
DOI:10.1038/s41541-022-00473-1