Mapping of CD8 T cell epitopes in human respiratory syncytial virus L protein.
OBJECTIVE
Since it has been reported that in humans there is a relationship between human respiratory syncytial virus (hRSV)-specific cytotoxic T lymphocytes and symptom reduction, and that the polymerase (structural L protein) is highly conserved among different strains, this work aimed to identify the CD8 T cell epitopes H-2(d) restricted within the L sequence for immunization purposes.


METHODS
We screened the hRSV strain A2 L protein sequence using two independent algorithms, SYFPEITHI and PRED/(BALB/c), to predict CD8 T cell epitopes. The selected peptides were synthesized and used to immunize BALB/c mice for the evaluation of T cell response. The production of IFN-γ from splenocytes of hRSV-infected animals stimulated by these peptides was assayed by ELISPOT.


RESULTS
Nine peptides showing the best binding scores to the BALB/c MHC-I molecules (H-2K(d), L(d) and D(d)) were selected. Sequence homology analysis showed that these sequences are conserved among different hRSV strains. Two of these peptides induced significant IFN-γ production by ex vivo-stimulated T cells.


CONCLUSIONS
Our results indicate that the hRSV L protein contains H-2(d)-restricted epitopes.
Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.
Yordanka
Y
Medina-Armenteros
Luis E
LE
Farinha-Arcieri
Catarina J M
CJ
Braga
Cassiano
C
Carromeu
Rodrigo E
RE
Tamura
Armando M
AM
Ventura
D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D012321:DNA-Directed RNA Polymerases / Q000276:immunology*; D058501:Enzyme-Linked Immunospot Assay; D018604:Epitope Mapping; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D007371:Interferon-gamma / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008807:Mice, Inbred BALB C; D018113:Respiratory Syncytial Virus, Human / Q000276:immunology*; D015678:Viral Structural Proteins / Q000276:immunology*
D018984:Epitopes, T-Lymphocyte; D015678:Viral Structural Proteins; D007371:Interferon-gamma; D012321:DNA-Directed RNA Polymerases