CarlosAlonso,Manuel Soto
252
commercial vaccines against canine leishmaniasis: Leishmune (based on Parasite
Fucose-‐Manose-‐Ligand) (12), Leishtec, basedona recombinant amastigoteantigen
namely A2 protein (13) and CaniLeish, composed on promastigotes secreted-‐
excreted factors (14, 15). In spite of the existence of these products, the search of
molecules for development of
Leishmania
vaccines continues, looking for
improving protection against different forms of leishmaniasis. There are recent
review articles covering the progress made towards the development of
Leishmania
vaccines, includingsomeof themost studiedparasiteproteins together
with theeffect of various adjuvants employed inexperimental vaccination trials (4,
11, 16-‐22). There is general consensus indicating that the establishment of a
protective anti-‐
Leishmania
responsemay require the inductionof parasite specific
long-‐lastingmemory T cells that will expand as effector T cells for the production
of IFN-‐gamma dependent responses specific for parasite antigens in order to
activate the leishmanicidal capacitiesof infectedmacrophages. In thisway,most of
the recent research is focused on the identification of the
Leishmania
molecules
that interacts with the host immune system and on the analysis of their
prophylactic properties when immunized in experimental models of infection as
second generation vaccines (based on parasite fractions or recombinant proteins)
or thirdgenerationvaccines (mainlyDNA-‐basedvaccines). In thisworkwemake a
review of these studies performed with different parasite proteins,
immunodominant antigens during infection, focusing on the results obtained
taking into consideration the implicationof different Spanish researchers, aloneor
in collaborativework, in order to show the important effortsmade in our country
during the last years, helping tomitigate theeffectsof thisemergingdisease.
2.
LEISHMANIA
SURFACEANTIGENS
A number of surface glycoproteins are present in promastigote forms of
Leishmania
parasites. The
Leishmania
proteinase GP63, one of themost abundant
surface-‐exposedproteinsonparasitepromastigotes (23, 24)hasbeendescribedas
an immunogenic protein during human VL (25). The GP63 is also an antigenic
molecule in canineVL, as describedby (26). Using a recombinant version of the
L.
infantum
GP63 (LiGP63) as well as some synthetic peptides derived from its
aminoacid sequence, Dr. Alonso’s laboratory (CentrodeBiologíaMolecular Severo
Ochoa, CSIC-‐UAM) was able to demonstrate that LiGP63 was recognized by the
100%of the sera from
L. infantum
infected dogs and that the C-‐terminal domain
was themost antigenic regionof theprotein. On thebasisof its surface localization
and its antigenicity, second generation vaccines related with GP63 and its
immunodominant epitopes have been extensively studied as vaccine candidates
usingmurinemodels of infection (Revised in (27)). Of special interest is thework
published by Cote-‐Sierra and coworkers (28) with the collaboration of Dr..
