PMID- 21713006
OWN - NLM
STAT- MEDLINE
DCOM- 20111121
LR  - 20211020
IS  - 1932-6203 (Electronic)
IS  - 1932-6203 (Linking)
VI  - 6
IP  - 6
DP  - 2011
TI  - Identification of a highly antigenic linear B cell epitope within Plasmodium 
      vivax apical membrane antigen 1 (AMA-1).
PG  - e21289
LID - 10.1371/journal.pone.0021289 [doi]
LID - e21289
AB  - Apical membrane antigen 1 (AMA-1) is considered to be a major candidate antigen 
      for a malaria vaccine. Previous immunoepidemiological studies of naturally 
      acquired immunity to Plasmodium vivax AMA-1 (PvAMA-1) have shown a higher 
      prevalence of specific antibodies to domain II (DII) of AMA-1. In the present 
      study, we confirmed that specific antibody responses from naturally infected 
      individuals were highly reactive to both full-length AMA-1 and DII. Also, we 
      demonstrated a strong association between AMA-1 and DII IgG and IgG subclass 
      responses. We analyzed the primary sequence of PvAMA-1 for B cell linear epitopes 
      co-occurring with intrinsically unstructured/disordered regions (IURs). The B 
      cell epitope comprising the amino acid sequence 290-307 of PvAMA-1 
      (SASDQPTQYEEEMTDYQK), with the highest prediction scores, was identified in 
      domain II and further selected for chemical synthesis and immunological testing. 
      The antigenicity of the synthetic peptide was identified by serological analysis 
      using sera from P. vivax-infected individuals who were knowingly reactive to the 
      PvAMA-1 ectodomain only, domain II only, or reactive to both antigens. Although 
      the synthetic peptide was recognized by all serum samples specific to domain II, 
      serum with reactivity only to the full-length protein presented 58.3% positivity. 
      Moreover, IgG reactivity against PvAMA-1 and domain II after depletion of 
      specific synthetic peptide antibodies was reduced by 18% and 33% (P = 0.0001 for 
      both), respectively. These results suggest that the linear epitope 
      SASDQPTQYEEEMTDYQK is highly antigenic during natural human infections and is an 
      important antigenic region of the domain II of PvAMA-1, suggesting its possible 
      future use in pre-clinical studies.
FAU - Bueno, Lilian Lacerda
AU  - Bueno LL
AD  - Departamento de Parasitologia, Instituto de Ciencias Biologicas, Universidade 
      Federal de Minas Gerais, Belo Horizonte, Brazil.
FAU - Lobo, Francisco Pereira
AU  - Lobo FP
FAU - Morais, Cristiane Guimaraes
AU  - Morais CG
FAU - Mourao, Luiza Carvalho
AU  - Mourao LC
FAU - de Avila, Ricardo Andrez Machado
AU  - de Avila RA
FAU - Soares, Irene Silva
AU  - Soares IS
FAU - Fontes, Cor Jesus
AU  - Fontes CJ
FAU - Lacerda, Marcus Vinicius
AU  - Lacerda MV
FAU - Chavez Olortegui, Carlos
AU  - Chavez Olortegui C
FAU - Bartholomeu, Daniella Castanheira
AU  - Bartholomeu DC
FAU - Fujiwara, Ricardo Toshio
AU  - Fujiwara RT
FAU - Braga, Erika Martins
AU  - Braga EM
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20110621
PL  - United States
TA  - PLoS One
JT  - PloS one
JID - 101285081
RN  - 0 (Antibodies, Protozoan)
RN  - 0 (Antigens, Protozoan)
RN  - 0 (Epitopes, B-Lymphocyte)
RN  - 0 (Membrane Proteins)
RN  - 0 (Peptides)
RN  - 0 (Protozoan Proteins)
RN  - 0 (apical membrane antigen I, Plasmodium)
SB  - IM
MH  - Adolescent
MH  - Adult
MH  - Aged
MH  - Amino Acid Sequence
MH  - Animals
MH  - Antibodies, Protozoan/blood/genetics/immunology
MH  - Antigens, Protozoan/genetics/*immunology
MH  - Epitopes, B-Lymphocyte/*immunology
MH  - Humans
MH  - Malaria, Vivax/blood/immunology/microbiology
MH  - Membrane Proteins/genetics/*immunology
MH  - Middle Aged
MH  - Molecular Sequence Data
MH  - Peptides/genetics/immunology
MH  - Plasmodium vivax/cytology/*immunology
MH  - Protozoan Proteins/genetics/*immunology
MH  - Young Adult
PMC - PMC3119695
COIS- Competing Interests: The authors have declared that no competing interests exist.
EDAT- 2011/06/30 06:00
MHDA- 2011/12/13 00:00
PMCR- 2011/06/21
CRDT- 2011/06/30 06:00
PHST- 2010/12/21 00:00 [received]
PHST- 2011/05/25 00:00 [accepted]
PHST- 2011/06/30 06:00 [entrez]
PHST- 2011/06/30 06:00 [pubmed]
PHST- 2011/12/13 00:00 [medline]
PHST- 2011/06/21 00:00 [pmc-release]
AID - PONE-D-11-00265 [pii]
AID - 10.1371/journal.pone.0021289 [doi]
PST - ppublish
SO  - PLoS One. 2011;6(6):e21289. doi: 10.1371/journal.pone.0021289. Epub 2011 Jun 21.