Antigenic epitope targets of rhesus macaques self-curing from Schistosoma mansoni infection

The self-cure of rhesus macaques from a schistosome infection and their subsequent strong immunity to a cercarial challenge should provide novel insights into the way these parasites can be eliminated by immunological attack. High-density arrays comprising overlapping 15-mer peptides from target proteins printed on glass slides can be used to screen sera from host species to determine antibody reactivity at the single epitope level. Careful selection of proteins, based on compositional studies, is crucial to encompass only those exposed on or secreted from the intra-mammalian stages and is intended to focus the analysis solely on targets mediating protection. We report the results of this approach using two pools of sera from hi- and lo-responder macaques undergoing self-cure, to screen arrays comprising tegument, esophageal gland, and gastrodermis proteins. We show that, overall, the target epitopes are the same in both groups, but the intensity of response is twice as strong in the high responders. In addition, apart from Sm25, tegument proteins elicit much weaker responses than those originating in the alimentary tract, as was apparent in IFNγR KO mice. We also highlight the most reactive epitopes in key proteins. Armed with this knowledge, we intend to use multi-epitope constructs in vaccination experiments, which seek to emulate the self-cure process in experimental animals and potentially in humans.

Schistosome proteomics: updates and clinical implications.

INTRODUCTION: Schistosomes are long-lived blood dwelling helminth parasites using intricate mechanisms to invade, mature, and reproduce inside their vertebrate hosts, whilst simultaneously deploying immune evasion strategies. Their multi-tissue organization and solid body plan presents particular problems for the definition of sub-proteomes. AREAS COVERED: Here, we focus on the two host-parasite interfaces of the adult worm accessible to the immune system, namely the tegument and the alimentary tract, but also on the secretions of the infective cercaria, the migrating schistosomulum and the mature egg. In parallel, we introduce the concepts of "leakyome' and 'disintegrome' to emphasize the importance of interpreting data in the context of schistosome biology so that misleading conclusions about the distinct proteome compositions are avoided. Lastly, we highlight the possible clinical implications of the reviewed proteomic findings for pathogenesis, vaccine design and diagnostics. EXPERT OPINION: Proteomics has provided considerable insights into the biology of schistosomes, most importantly for rational selection of novel vaccine candidates that might confer protective immunity, but also into the pathogenesis of schistosomiasis. However, given the increasing sensitivity of mass spectrometric instrumentation, we stress the need for care in data interpretation since schistosomes do not deviate from the fundamental rules of eukaryotic cell biology.

Epitope mapping of exposed tegument and alimentary tract proteins identifies putative antigenic targets of the attenuated schistosome vaccine

The radiation-attenuated cercarial vaccine remains the gold standard for the induction of protective immunity against Schistosoma mansoni. Furthermore, the protection can be passively transferred to naïve recipient mice from multiply vaccinated donors, especially IFNgR KO mice. We have used such sera versus day 28 infection serum, to screen peptide arrays and identify likely epitopes that mediate the protection. The arrays encompassed 55 secreted or exposed proteins from the alimentary tract and tegument, the principal interfaces with the host bloodstream. The proteins were printed onto glass slides as overlapping 15mer peptides, reacted with primary and secondary antibodies, and reactive regions detected using an Agilent array scanner. Pep Slide Analyzer software provided a numerical value above background for each peptide from which an aggregate score could be derived for a putative epitope. The reactive regions of 26 proteins were mapped onto crystal structures using the CCP4 molecular graphics, to aid selection of peptides with the greatest accessibility and reactivity, prioritizing vaccine over infection serum. A further eight MEG proteins were mapped to regions conserved between family members. The result is a list of priority peptides from 44 proteins for further investigation in multiepitope vaccine constructs and as targets of monoclonal antibodies.

Epitope Mapping of Exposed Tegument and Alimentary Tract Proteins Identifies Putative Antigenic Targets of the Attenuated Schistosome Vaccine.

The radiation-attenuated cercarial vaccine remains the gold standard for the induction of protective immunity against Schistosoma mansoni. Furthermore, the protection can be passively transferred to naïve recipient mice from multiply vaccinated donors, especially IFNgR KO mice. We have used such sera versus day 28 infection serum, to screen peptide arrays and identify likely epitopes that mediate the protection. The arrays encompassed 55 secreted or exposed proteins from the alimentary tract and tegument, the principal interfaces with the host bloodstream. The proteins were printed onto glass slides as overlapping 15mer peptides, reacted with primary and secondary antibodies, and reactive regions detected using an Agilent array scanner. Pep Slide Analyzer software provided a numerical value above background for each peptide from which an aggregate score could be derived for a putative epitope. The reactive regions of 26 proteins were mapped onto crystal structures using the CCP4 molecular graphics, to aid selection of peptides with the greatest accessibility and reactivity, prioritizing vaccine over infection serum. A further eight MEG proteins were mapped to regions conserved between family members. The result is a list of priority peptides from 44 proteins for further investigation in multiepitope vaccine constructs and as targets of monoclonal antibodies.

Investigation of the midgut structure and ultrastructure in Cimex lectularius and Cimex pipistrelli (Hemiptera: Cimicidae).

Cimicidae are temporary ectoparasites, which means that they cannot obtain food continuously. Both Cimex species examined here, Cimex lectularius (Linnaeus 1758) and Cimex pipistrelli (Jenyns 1839), can feed on a non-natal host, C. lectularius from humans on bats, C. pipistrelli on humans, but never naturally. The midgut of C. lectularius and C. pipistrelli is composed of three distinct regions-the anterior midgut (AMG), which has a sack-like shape, the long tube-shaped middle midgut (MMG), and the posterior midgut (PMG). The different ultrastructures of the AMG, MMG, and PMG in both of the species examined suggest that these regions must fulfill different functions in the digestive system. Ultrastructural analysis showed that the AMG fulfills the role of storing food and synthesizing and secreting enzymes, while the MMG is the main organ for the synthesis of enzymes, secretion, and the storage of the reserve material. Additionally, both regions, the AMG and MMG, are involved in water absorption in the digestive system of both Cimex species. The PMG is the part of the midgut in which spherites accumulate. The results of our studies confirm the suggestion of former authors that the structure of the digestive tract of insects is not attributed solely to diet but to the basic adaptation of an ancestor.

Gross anatomy and histology of the alimentary system of Characidae (Teleostei: Ostariophysi: Characiformes) and potential phylogenetic information

A compared study of the morphology of the alimentary tract and liver of seven selected species corresponding to the main clades of the Characidae family is presented herein. Three new set of characters corresponding to 1) alimentary tract gross anatomy, 2) alimentary tract histology and 3) liver gross anatomy are evaluated as potential sources of data for future phylogenetic studies of the Characidae. Not considerable interspecific variation was observed at the histological level and therefore this source is not considered to be phylogenetically informative at the taxonomic level analyzed. In contrast, liver and alimentary tract gross anatomy presented important interspecific variation while a relatively homogenous intraspecific morphology was observed. Those characters are optimized in tree-topologies from previous phylogenetic analyses and their evolution and potential relationship with ecological traits are discussed.

Un estudio comparado de la morfología del tracto alimentario y el hígado de siete especies seleccionadas correspondientes a los principales clados de la familia Characidae es presentada aquí. Tres nuevos conjuntos de caracteres correspondientes a 1) anatomía gruesa del tracto alimentario, 2) histología del tracto alimentario y 3) anatomía gruesa del hígado son evaluados aquí como potenciales fuentes de información para futuros estudios filogenéticos de los Characidae. No se observó una variación intraespecífica considerable a nivel histológico y consecuentemente esta fuente no es considerada como informativa filogenéticamente al nivel taxonómico analizado. En contraste, la anatomía gruesa del hígado y el tracto alimentario presentaron una variación interespecífica importante mientras que una relativamente homogénea variación intraespecífica fue observada. Estos caracteres son optimizados en topologías de árboles de análisis filogenéticos previos y su evolución y potencial relación con características ecológicas son discutidas.

Gross anatomy and histology of the alimentary system of Characidae (Teleostei: Ostariophysi: Characiformes) and potential phylogenetic information

A compared study of the morphology of the alimentary tract and liver of seven selected species corresponding to the main clades of the Characidae family is presented herein. Three new set of characters corresponding to 1) alimentary tract gross anatomy, 2) alimentary tract histology and 3) liver gross anatomy are evaluated as potential sources of data for future phylogenetic studies of the Characidae. Not considerable interspecific variation was observed at the histological level and therefore this source is not considered to be phylogenetically informative at the taxonomic level analyzed. In contrast, liver and alimentary tract gross anatomy presented important interspecific variation while a relatively homogenous intraspecific morphology was observed. Those characters are optimized in tree-topologies from previous phylogenetic analyses and their evolution and potential relationship with ecological traits are discussed.(AU)

Un estudio comparado de la morfología del tracto alimentario y el hígado de siete especies seleccionadas correspondientes a los principales clados de la familia Characidae es presentada aquí. Tres nuevos conjuntos de caracteres correspondientes a 1) anatomía gruesa del tracto alimentario, 2) histología del tracto alimentario y 3) anatomía gruesa del hígado son evaluados aquí como potenciales fuentes de información para futuros estudios filogenéticos de los Characidae. No se observó una variación intraespecífica considerable a nivel histológico y consecuentemente esta fuente no es considerada como informativa filogenéticamente al nivel taxonómico analizado. En contraste, la anatomía gruesa del hígado y el tracto alimentario presentaron una variación interespecífica importante mientras que una relativamente homogénea variación intraespecífica fue observada. Estos caracteres son optimizados en topologías de árboles de análisis filogenéticos previos y su evolución y potencial relación con características ecológicas son discutidas.(AU)

Anatomia visceral comparada de seis espécies de Amphisbaenidae (Squamata: Amphisbaenia)

Visceral anatomy of amphisbaenids Amphisbaena vermicularis Wagler, 1824; Anops kingii Bell, 1833; Aulura anomala Barbour, 1914; Bronia bedai Vanzolini, 1991; Cercolophia cuiabana Strüssmann & Carvalho, 2001, and Leposternon microcephalum Wagler, 1824 were comparatively described and the size and the position of the organs in the pleuroperitoneal cavity was established in relation to the ventral scutellation. The main results were: the right lung presents different degrees of size reduction compared to the left lung, being conspicuous only in A. anomala, and L. microcephalum; the limit between small and large intestines is clear due to the presence of a caecum; the right lobe of the liver is larger than the left one, but its length varies within the same species and among species; the right gonad occupies a more cranial position in relation to the left one, in all six studied species; the right ovary is also larger than the left one in all studied specimens, whereas the left testicle can be larger or of the same size as the right one in some specimens; the shape of the testicles varies from elongated, kidney-shaped or oval; kidneys are symmetrically positioned at the caudal portion of the pleuroperitoneal cavity and one kidney can be larger than the other.

Anatomia visceral comparada de seis espécies de Amphisbaenidae (Squamata: Amphisbaenia)

Visceral anatomy of amphisbaenids Amphisbaena vermicularis Wagler, 1824; Anops kingii Bell, 1833; Aulura anomala Barbour, 1914; Bronia bedai Vanzolini, 1991; Cercolophia cuiabana Strüssmann & Carvalho, 2001, and Leposternon microcephalum Wagler, 1824 were comparatively described and the size and the position of the organs in the pleuroperitoneal cavity was established in relation to the ventral scutellation. The main results were: the right lung presents different degrees of size reduction compared to the left lung, being conspicuous only in A. anomala, and L. microcephalum; the limit between small and large intestines is clear due to the presence of a caecum; the right lobe of the liver is larger than the left one, but its length varies within the same species and among species; the right gonad occupies a more cranial position in relation to the left one, in all six studied species; the right ovary is also larger than the left one in all studied specimens, whereas the left testicle can be larger or of the same size as the right one in some specimens; the shape of the testicles varies from elongated, kidney-shaped or oval; kidneys are symmetrically positioned at the caudal portion of the pleuroperitoneal cavity and one kidney can be larger than the other.

Anatomia visceral comparada de seis espécies de Amphisbaenidae (Squamata: Amphisbaenia)

Visceral anatomy of amphisbaenids Amphisbaena vermicularis Wagler, 1824; Anops kingii Bell, 1833; Aulura anomala Barbour, 1914; Bronia bedai Vanzolini, 1991; Cercolophia cuiabana Strüssmann & Carvalho, 2001, and Leposternon microcephalum Wagler, 1824 were comparatively described and the size and the position of the organs in the pleuroperitoneal cavity was established in relation to the ventral scutellation. The main results were: the right lung presents different degrees of size reduction compared to the left lung, being conspicuous only in A. anomala, and L. microcephalum; the limit between small and large intestines is clear due to the presence of a caecum; the right lobe of the liver is larger than the left one, but its length varies within the same species and among species; the right gonad occupies a more cranial position in relation to the left one, in all six studied species; the right ovary is also larger than the left one in all studied specimens, whereas the left testicle can be larger or of the same size as the right one in some specimens; the shape of the testicles varies from elongated, kidney-shaped or oval; kidneys are symmetrically positioned at the caudal portion of the pleuroperitoneal cavity and one kidney can be larger than the other.

Anatomia visceral comparada de seis espécies de Amphisbaenidae (Squamata: Amphisbaenia)

Visceral anatomy of amphisbaenids Amphisbaena vermicularis Wagler, 1824; Anops kingii Bell, 1833; Aulura anomala Barbour, 1914; Bronia bedai Vanzolini, 1991; Cercolophia cuiabana Strüssmann & Carvalho, 2001, and Leposternon microcephalum Wagler, 1824 were comparatively described and the size and the position of the organs in the pleuroperitoneal cavity was established in relation to the ventral scutellation. The main results were: the right lung presents different degrees of size reduction compared to the left lung, being conspicuous only in A. anomala, and L. microcephalum; the limit between small and large intestines is clear due to the presence of a caecum; the right lobe of the liver is larger than the left one, but its length varies within the same species and among species; the right gonad occupies a more cranial position in relation to the left one, in all six studied species; the right ovary is also larger than the left one in all studied specimens, whereas the left testicle can be larger or of the same size as the right one in some specimens; the shape of the testicles varies from elongated, kidney-shaped or oval; kidneys are symmetrically positioned at the caudal portion of the pleuroperitoneal cavity and one kidney can be larger than the other.

Anatomia visceral comparada de seis espécies de Amphisbaenidae (Squamata: Amphisbaenia)

Visceral anatomy of amphisbaenids Amphisbaena vermicularis Wagler, 1824; Anops kingii Bell, 1833; Aulura anomala Barbour, 1914; Bronia bedai Vanzolini, 1991; Cercolophia cuiabana Strüssmann & Carvalho, 2001, and Leposternon microcephalum Wagler, 1824 were comparatively described and the size and the position of the organs in the pleuroperitoneal cavity was established in relation to the ventral scutellation. The main results were: the right lung presents different degrees of size reduction compared to the left lung, being conspicuous only in A. anomala, and L. microcephalum; the limit between small and large intestines is clear due to the presence of a caecum; the right lobe of the liver is larger than the left one, but its length varies within the same species and among species; the right gonad occupies a more cranial position in relation to the left one, in all six studied species; the right ovary is also larger than the left one in all studied specimens, whereas the left testicle can be larger or of the same size as the right one in some specimens; the shape of the testicles varies from elongated, kidney-shaped or oval; kidneys are symmetrically positioned at the caudal portion of the pleuroperitoneal cavity and one kidney can be larger than the other.

Aerobic bacterial microbiota in stomoxys calcitrans: preliminary studies in Brazil / Microbiota bacteriana aeróbica em Stomoxys calcitrans: estudos preliminares no Brasil

The stable fly, Stomoxys calcitrans, has a great importance in medical and veterinary health due to its feeding and reproductive habits, which can disseminate some pathogenic agents among hosts even at long distances. This study aimed to describe, for the first time in Brazil, the bacterial microbiota in segments of the stable fly. Bacterial species were isolated from three different segments (cuticle, mouth parts and abdominal alimentary tract) of the stable fly. Twenty dairy farms were visited in four municipalities: Barra Mansa, Quatis, Resende and Rio Claro in the State of Rio de Janeiro in order to collect 20 flies in each site. Dissection of the flies and procedures of isolation and identification of bacterial species were performed. A total of 161 colonies of 33 distinct species were isolated, such as Escherichia coli, Staphylococcus aureus, and S. intermedius. Stomoxys calcitrans may harbor bacterial agents on their cuticle, mouth parts and abdominal alimentary tract and these bacteria may be pathogenic to their hosts.

A mosca dos estábulos, Stomoxys calcitrans, possui grande importância médica e veterinária devido a seus hábitos alimentares e reprodutivos, visto que pode disseminar agentes patogênicos para hospedeiros, mesmo a longas distâncias. Esse estudo teve por objetivo, pela primeira vez no Brasil, descrever a microbiota bacteriana de segmentos da mosca dos estábulos. As espécies bacterianas foram isoladas de três diferentes segmentos (superfície externa, aparelho bucal e trato digestivo abdominal) de S. calcitrans. Foram visitadas 20 fazendas leiteiras em quatro municípios: Barra Mansa, Quatis, Resende e Rio Claro no Estado do Rio de Janeiro para coletar 20 moscas em cada uma delas. A dissecção das moscas e os procedimentos de isolamento e identificação bacteriana foram realizados. Um total de 161 colônias de 33 espécies distintas foi isolado, dentre elas Escherichia coli, Staphylococcus aureus e S. intermedius. Stomoxys calcitrans pode veicular agentes bacterianos presentes na superfície externa, aparelho bucal e trato digestivo abdominal e essas bacterias possuem potencial patogênico a diversos hospedeiros deste muscídeo.

Aerobic bacterial microbiota in stomoxys calcitrans: preliminary studies in Brazil

The stable fly, Stomoxys calcitrans, has a great importance in medical and veterinary health due to its feeding and reproductive habits, which can disseminate some pathogenic agents among hosts even at long distances. This study aimed to describe, for the first time in Brazil, the bacterial microbiota in segments of the stable fly. Bacterial species were isolated from three different segments (cuticle, mouth parts and abdominal alimentary tract) of the stable fly. Twenty dairy farms were visited in four municipalities: Barra Mansa, Quatis, Resende and Rio Claro in the State of Rio de Janeiro in order to collect 20 flies in each site. Dissection of the flies and procedures of isolation and identification of bacterial species were performed. A total of 161 colonies of 33 distinct species were isolated, such as Escherichia coli, Staphylococcus aureus, and S. intermedius. Stomoxys calcitrans may harbor bacterial agents on their cuticle, mouth parts and abdominal alimentary tract and these bacteria may be pathogenic to their hosts.

A mosca dos estábulos, Stomoxys calcitrans, possui grande importância médica e veterinária devido a seus hábitos alimentares e reprodutivos, visto que pode disseminar agentes patogênicos para hospedeiros, mesmo a longas distâncias. Esse estudo teve por objetivo, pela primeira vez no Brasil, descrever a microbiota bacteriana de segmentos da mosca dos estábulos. As espécies bacterianas foram isoladas de três diferentes segmentos (superfície externa, aparelho bucal e trato digestivo abdominal) de S. calcitrans. Foram visitadas 20 fazendas leiteiras em quatro municípios: Barra Mansa, Quatis, Resende e Rio Claro no Estado do Rio de Janeiro para coletar 20 moscas em cada uma delas. A dissecção das moscas e os procedimentos de isolamento e identificação bacteriana foram realizados. Um total de 161 colônias de 33 espécies distintas foi isolado, dentre elas Escherichia coli, Staphylococcus aureus e S. intermedius. Stomoxys calcitrans pode veicular agentes bacterianos presentes na superfície externa, aparelho bucal e trato digestivo abdominal e essas bacterias possuem potencial patogênico a diversos hospedeiros deste muscídeo.