Abstract
We assessed immunogenicity of a malaria DNA vaccine administered by needle i.m. or needleless jet injection [i.m. or i.m./intradermally (i.d.)] in 14 volunteers. Antigen-specific IFN-gamma responses were detected by enzyme-linked immunospot (ELISPOT) assays in all subjects to multiple 9- to 23-aa peptides containing class I and/or class II restricted epitopes, and were dependent on both CD8(+) and CD4(+) T cells. Overall, frequency of response was significantly greater after i.m. jet injection. CD8(+)-dependent cytotoxic T lymphocytes (CTL) were detected in 8/14 volunteers. Demonstration in humans of elicitation of the class I restricted IFN-gamma responses we believe necessary for protection against the liver stage of malaria parasites brings us closer to an effective malaria vaccine.
Publication types
-
Research Support, U.S. Gov't, Non-P.H.S.
MeSH terms
-
Adolescent
-
Adult
-
Amino Acid Sequence
-
Animals
-
Antigens, Protozoan / immunology
-
CD4-Positive T-Lymphocytes / immunology*
-
DNA, Protozoan / immunology*
-
Humans
-
Interferon-gamma / biosynthesis
-
Interleukin-4 / analysis
-
Malaria Vaccines / administration & dosage
-
Malaria Vaccines / immunology*
-
Malaria, Falciparum / immunology
-
Malaria, Falciparum / prevention & control
-
Molecular Sequence Data
-
Plasmodium falciparum / immunology*
-
Protozoan Proteins / genetics*
-
T-Lymphocyte Subsets / immunology
-
T-Lymphocytes, Cytotoxic / immunology*
-
Vaccines, DNA / administration & dosage
-
Vaccines, DNA / immunology*
Substances
-
Antigens, Protozoan
-
DNA, Protozoan
-
Malaria Vaccines
-
Protozoan Proteins
-
Vaccines, DNA
-
circumsporozoite protein, Protozoan
-
Interleukin-4
-
Interferon-gamma