title: The gp63 Gene Cluster Is Highly Polymorphic in Natural Leishmania (Viannia) braziliensis Populations, but Functional Sites Are Conserved.
abstract: GP63 or leishmanolysin is the major surface protease of Leishmania spp. involved in parasite virulence and host cell interaction. As such, GP63 is a potential target of eventual vaccines against these protozoa. In the current study we evaluate the polymorphism of gp63 in Leishmania (Viannia) braziliensis isolated from two sets of American tegumentary leishmaniasis (ATL) cases from Corte de Pedra, Brazil, including 35 cases diagnosed between 1994 and 2001 and 6 cases diagnosed between 2008 and 2011. Parasites were obtained from lesions by needle aspiration and cultivation. Genomic DNA was extracted, and 405 bp fragments, including sequences encoding the putative macrophage interacting sites, were amplified from gp63 genes of all isolates. DNA amplicons were cloned into plasmid vectors and ten clones per L. (V.) braziliensis isolate were sequenced. Alignment of cloned sequences showed extensive polymorphism among gp63 genes within, and between parasite isolates. Overall, 45 different polymorphic alleles were detected in all samples, which could be segregated into two clusters. Cluster one included 25, and cluster two included 20 such genotypes. The predicted peptides showed overall conservation below 50%. In marked contrast, the conservation at segments with putative functional domains approached 90% (Fisher's exact test p<0.0001). These findings show that gp63 is very polymorphic even among parasites from a same endemic focus, but the functional domains interacting with the mammalian host environment are conserved.
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Lilian S
authors.initials: LS
authors.lastname: Medina
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Bruno Araújo
authors.initials: BA
authors.lastname: Souza
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Adriano
authors.initials: A
authors.lastname: Queiroz
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.|Instituto Nacional de Ciência e Tecnologia - Doenças Tropicais (INCT-DT), Brazil.
authors.forename: Luiz Henrique
authors.initials: LH
authors.lastname: Guimarães
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.|Instituto Nacional de Ciência e Tecnologia - Doenças Tropicais (INCT-DT), Brazil.
authors.forename: Paulo Roberto
authors.initials: PR
authors.lastname: Lima Machado
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.|Instituto Nacional de Ciência e Tecnologia - Doenças Tropicais (INCT-DT), Brazil.|Centro de Pesquisa Gonçalo Moniz (Fiocruz), Salvador, Bahia, Brazil.
authors.forename: Edgar
authors.initials: E
authors.lastname: M Carvalho
authors.affiliation: Departments of Internal Medicine and Microbiology, University of Iowa and the VA Medical Center, Iowa City, Iowa, United States of America.
authors.forename: Mary Edythe
authors.initials: ME
authors.lastname: Wilson
authors.affiliation: Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.|Instituto Nacional de Ciência e Tecnologia - Doenças Tropicais (INCT-DT), Brazil.|Departamento de Ciências da Biointeração, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Albert
authors.initials: A
authors.lastname: Schriefer
mesh_terms: D001938:Brazil; D016054:DNA, Protozoan; D018503:Genome, Protozoan; D007892:Leishmania braziliensis / Q000235:genetics* / Q000302:isolation & purification; D016773:Leishmaniasis, Cutaneous / Q000469:parasitology*; D008666:Metalloendopeptidases / Q000235:genetics*; D005810:Multigene Family; D011110:Polymorphism, Genetic; D015800:Protozoan Proteins / Q000235:genetics*
chemical_list: D016054:DNA, Protozoan; D015800:Protozoan Proteins; D008666:Metalloendopeptidases; C055146:glycoprotein gp63, Leishmania