Safety and elicitation of humoral and cellular responses in colombian malaria-naive volunteers by a Plasmodium vivax circumsporozoite protein-derived synthetic vaccine.
Substantial experimental evidence indicates that the Plasmodium circumsporozoite (CS) protein has great potential as a vaccine candidate. We tested the safety and immunogenicity of vaccines composed of P. vivax CS-derived synthetic peptides. Sixty-nine healthy, malaria-naive volunteers were randomized to receive three injections of placebo or synthetic proteins N, R, or C (10, 30, or 100 microg/dose) in a double-blinded fashion. Vaccines were well tolerated and no serious adverse events were observed. Peptides N and R elicited humoral responses at all doses; peptide C elicicted these responses only at doses of 30 and 100 microg. The N peptide at a dose of 100 microg elicited the greatest antibody response. Antibodies to the three peptides recognized P. vivax sporozoites in an immunofluorescent antibody test. Peripheral blood mononuclear cells from most immunized volunteers also produced interferon-gamma upon peptide in vitro stimulation. These vaccines appear safe, well tolerated, and immunogenic in malaria-naive volunteers. Further optimization and development of this vaccine is being attempted to conduct phase II clinical trials.
Herrera
Sócrates
S
Instituto de Inmunología, Universidad del Valle, Cali, Colombia. sherrera@inmuno.org
Bonelo
Anilza
A
Perlaza
Blanca Liliana
BL
Fernández
Olga Lucía
OL
Victoria
Leonardo
L
Lenis
Ana Milena
AM
Soto
Liliana
L
Hurtado
Hugo
H
Acuña
Lina María
LM
Vélez
Juan Diego
JD
Palacios
Ricardo
R
Chen-Mok
Mario
M
Corradin
Giampietro
G
Arévalo-Herrera
Myriam
M
D000293:Adolescent; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D017780:Malaria Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D008297:Male; D010966:Plasmodium vivax / Q000276:immunology*; D015800:Protozoan Proteins / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
D000913:Antibodies, Protozoan; D017780:Malaria Vaccines; D015800:Protozoan Proteins; D014614:Vaccines, Synthetic; C041595:circumsporozoite protein, Protozoan; D007371:Interferon-gamma