Pre-Erythrocytic Vaccines against Malaria

Camila Marques-da-Silva; Kristen Peissig; Samarchith P. Kurup

doi:10.3390/vaccines8030400

Pre-Erythrocytic Vaccines against Malaria

Vaccines ◽

10.3390/vaccines8030400 ◽

2020 ◽

Vol 8 (3) ◽

pp. 400

Author(s):

Camila Marques-da-Silva ◽

Kristen Peissig ◽

Samarchith P. Kurup

Keyword(s):

Developmental Stages ◽

Erythrocytic Stage ◽

Vaccine Candidates

Malaria, caused by the protozoan Plasmodium, is a devastating disease with over 200 million new cases reported globally every year. Although immunization is arguably the best strategy to eliminate malaria, despite decades of research in this area we do not have an effective, clinically approved antimalarial vaccine. The current impetus in the field is to develop vaccines directed at the pre-erythrocytic developmental stages of Plasmodium, utilizing novel vaccination platforms. We here review the most promising pre-erythrocytic stage antimalarial vaccine candidates.

Download Full-text

From genomes to vaccines: Leishmania as a model

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2001.0985 ◽

2002 ◽

Vol 357 (1417) ◽

pp. 5-11 ◽

Cited By ~ 37

Author(s):

Renata Almeida ◽

Alan Norrish ◽

Mark Levick ◽

David Vetrie ◽

Tom Freeman ◽

...

Keyword(s):

Transcriptional Regulation ◽

Leishmania Major ◽

Developmental Stages ◽

Rapid Screening ◽

Developmental Cycle ◽

Cdna Clones ◽

Vaccine Candidates ◽

Est Analysis ◽

Protective Antigens ◽

Unique Genes

The 35 Mb genome of Leishmania should be sequenced by late 2002. It contains approximately 8500 genes that will probably translate into more than 10 000 proteins. In the laboratory we have been piloting strategies to try to harness the power of the genome–proteome for rapid screening of new vaccine candidate. To this end, microarray analysis of 1094 unique genes identified using an EST analysis of 2091 cDNA clones from spliced leader libraries prepared from different developmental stages of Leishmania has been employed. The plan was to identify amastigote–expressed genes that could be used in high–throughput DNA–vaccine screens to identify potential new vaccine candidates. Despite the lack of transcriptional regulation that polycistronic transcription in Leishmania dictates, the data provide evidence for a high level of post–transcriptional regulation of RNA abundance during the developmental cycle of promastigotes in culture and in lesion–derived amastigotes of Leishmania major . This has provided 147 candidates from the 1094 unique genes that are specifically upregulated in amastigotes and are being used in vaccine studies. Using DNA vaccination, it was demonstrated that pooling strategies can work to identify protective vaccines, but it was found that some potentially protective antigens are masked by other disease–exacerbatory antigens in the pool. A total of 100 new vaccine candidates are currently being tested separately and in pools to extend this analysis, and to facilitate retrospective bioinformatic analysis to develop predictive algorithms for sequences that constitute potentially protective antigens. We are also working with other members of the Leishmania Genome Network to determine whether RNA expression determined by microarray analyses parallels expression at the protein level. We believe we are making good progress in developing strategies that will allow rapid translation of the sequence of Leishmania into potential interventions for disease control in humans.

Download Full-text

Utility of the Trypanosoma cruzi Sequence Database for Identification of Potential Vaccine Candidates by In Silico and In Vitro Screening

Infection and Immunity ◽

10.1128/iai.72.11.6245-6254.2004 ◽

2004 ◽

Vol 72 (11) ◽

pp. 6245-6254 ◽

Cited By ~ 50

Author(s):

Vandanajay Bhatia ◽

Mala Sinha ◽

Bruce Luxon ◽

Nisha Garg

Keyword(s):

Trypanosoma Cruzi ◽

Developmental Stages ◽

Expressed Sequence Tag ◽

Genomic Sequence ◽

Genome Mining ◽

Surface Proteins ◽

Vaccine Candidates ◽

Genes Encoding ◽

Potential Vaccine

ABSTRACT Glycosylphosphatidylinositol (GPI)-anchored proteins are abundantly expressed in the infective and intracellular stages of Trypanosoma cruzi and are recognized as antigenic targets by both the humoral and cellular arms of the immune system. Previously, we demonstrated the efficacy of genes encoding GPI-anchored proteins in eliciting partially protective immunity to T. cruzi infection and disease, suggesting their utility as vaccine candidates. For the identification of additional vaccine targets, in this study we screened the T. cruzi expressed sequence tag (EST) and genomic sequence survey (GSS) databases. By applying a variety of web-based genome-mining tools to the analysis of ∼2,500 sequences, we identified 348 (37.6%) EST and 260 (17.4%) GSS sequences encoding novel parasite-specific proteins. Of these, 19 sequences exhibited the characteristics of secreted and/or membrane-associated GPI proteins. Eight of the selected sequences were amplified to obtain genes TcG1, TcG2, TcG3, TcG4, TcG5, TcG6, TcG7, and TcG8 (TcG1-TcG8) which are expressed in different developmental stages of the parasite and conserved in the genome of a variety of T. cruzi strains. Flow cytometry confirmed the expression of the antigens encoded by the cloned genes as surface proteins in trypomastigote and/or amastigote stages of T. cruzi. When delivered as a DNA vaccine, genes TcG1-TcG6 elicited a parasite-specific antibody response in mice. Except for TcG5, antisera to genes TcG1-TcG6 exhibited trypanolytic activity against the trypomastigote forms of T. cruzi, a property known to correlate with the immune control of T. cruzi. Taken together, our results validate the applicability of bioinformatics in genome mining, resulting in the identification of T. cruzi membrane-associated proteins that are potential vaccine candidates.

Download Full-text

Comparative recognition by human IgG antibodies of recombinant proteins representing three asexual erythrocytic stage vaccine candidates of Plasmodium vivax

Memórias do Instituto Oswaldo Cruz ◽

10.1590/s0074-02762007005000040 ◽

2007 ◽

Vol 102 (3) ◽

pp. 335-340 ◽

Cited By ~ 26

Author(s):

Mayara B Barbedo ◽

Ricardo Ricci ◽

Maria Carolina S Jimenez ◽

Maristela G Cunha ◽

Syed S Yazdani ◽

...

Keyword(s):

Plasmodium Vivax ◽

Recombinant Proteins ◽

Igg Antibodies ◽

Erythrocytic Stage ◽

Human Igg ◽

Vaccine Candidates

Download Full-text

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005161x ◽

1974 ◽

Vol 32 ◽

pp. 320-321

Author(s):

J. P. Revel

Keyword(s):

Developmental Stages ◽

Three Dimensional ◽

Cell Movement ◽

Cellular Interactions ◽

Serial Sections ◽

Cell Sheets ◽

Freeze Etching ◽

Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

Download Full-text

Electron investigations of rhabdovirus-like particles in mexican bean beetles and crickets

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082753 ◽

1978 ◽

Vol 36 (2) ◽

pp. 378-379

Author(s):

J. R. Adams ◽

G. J Tompkins ◽

A. M. Heimpel ◽

E. Dougherty

Keyword(s):

Biological Control ◽

Integrated Pest Management ◽

Pest Management ◽

Developmental Stages ◽

Management Program ◽

Acheta Domesticus ◽

Epilachna Varivestis ◽

House Cricket ◽

Similar Morphology ◽

Bean Beetle

As part of a continual search for potential pathogens of insects for use in biological control or on an integrated pest management program, two bacilliform virus-like particles (VLP) of similar morphology have been found in the Mexican bean beetle Epilachna varivestis Mulsant and the house cricket, Acheta domesticus (L. ).Tissues of diseased larvae and adults of E. varivestis and all developmental stages of A. domesticus were fixed according to procedures previously described. While the bean beetles displayed no external symptoms, the diseased crickets displayed a twitching and shaking of the metathoracic legs and a lowered rate of activity.Examinations of larvae and adult Mexican bean beetles collected in the field in 1976 and 1977 in Maryland and field collected specimens brought into the lab in the fall and reared through several generations revealed that specimens from each collection contained vesicles in the cytoplasm of the midgut filled with hundreds of these VLP's which were enveloped and measured approximately 16-25 nm x 55-110 nm, the shorter VLP's generally having the greater width (Fig. 1).

Download Full-text

The Fine Structure of the Sheath of Volvox Carteri f. Weismannia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079231 ◽

1977 ◽

Vol 35 ◽

pp. 346-347

Author(s):

Regina Birchem

Keyword(s):

Developmental Stages ◽

Ruthenium Red ◽

Sulfated Polysaccharides ◽

Volvox Carteri ◽

High Voltage Electron Microscopy ◽

Ultrastructural Studies ◽

Voltage Electron ◽

Sheath Formation ◽

And Inversion ◽

Sheath Material

Spheroids of the green colonial alga Volvox consist of biflagellate Chlamydomonad-like cells embedded in a transparent sheath. The sheath, important as a substance through which metabolic materials, light, and the sexual inducer must pass to and from the cells, has been shown to have an ordered structure (1,2). It is composed of both protein and carbohydrate (3); studies of V. rousseletii indicate an outside layer of sulfated polysaccharides (4).Ultrastructural studies of the sheath material in developmental stages of V. carteri f. weismannia were undertaken employing variations in the standard fixation procedure, ruthenium red, diaminobenzidine, and high voltage electron microscopy. Sheath formation begins after the completion of cell division and inversion of the daughter spheroids. Golgi, rough ER, and plasma membrane are actively involved in phases of sheath synthesis (Fig. 1). Six layers of ultrastructurally differentiated sheath material have been identified.

Download Full-text

Localization of acid phosphatases in root cap of rice plant

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100085423 ◽

1991 ◽

Vol 49 ◽

pp. 224-225

Author(s):

Y. R. Chen ◽

Y. F. Huang ◽

W. S. Chen

Keyword(s):

Rice Plant ◽

Developmental Stages ◽

Uranyl Acetate ◽

Root Cap ◽

Plant Tissues ◽

Acid Phosphatases ◽

Root Tips ◽

Buffer Solution ◽

Cacodylate Buffer ◽

Ethanol Series

Acid phosphatases are widely distributed in different tisssues of various plants. Studies on subcellular localization of acid phosphatases show they might be present in cell wall, plasma lemma, mitochondria, plastid, vacuole and nucleus. However, their localization in rice cell varies with developmental stages of cells and plant tissues. In present study, acid phosphatases occurring in root cap are examined.Sliced root tips of ten-day-old rice(Oryza sativa) seedlings were fixed in 0.1M cacodylate buffer containing 2.5% glutaraldehyde for 2h, washed overnight in same buffer solution, incubated in Gomori's solution at 37° C for 90min, post-fixed in OsO4, dehydrated in ethanol series and finally embeded in Spurr's resin. Sections were doubly stained with uranyl acetate and lead citrate, and observed under Hitachi H-600 at 75 KV.

Download Full-text

Psychosocial Risks and Management for Children and Adolescents With 22q11.2 Deletion Syndrome

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2019_pers-sig5-2019-0002 ◽

2019 ◽

Vol 4 (4) ◽

pp. 633-640 ◽

Cited By ~ 1

Author(s):

Canice E. Crerand ◽

Ari N. Rabkin

Keyword(s):

Cognitive Abilities ◽

Psychotic Disorders ◽

Developmental Stages ◽

Early Adulthood ◽

22Q11.2 Deletion Syndrome ◽

Deletion Syndrome ◽

22Q11.2 Deletion ◽

Psychosocial Risks ◽

Empirically Supported ◽

Specific Education

Purpose This article reviews the psychosocial risks associated with 22q11.2 deletion syndrome, a relatively common genetic condition associated with a range of physical and psychiatric problems. Risks associated with developmental stages from infancy through adolescence and early adulthood are described, including developmental, learning, and intellectual disabilities as well as psychiatric disorders including anxiety, mood, and psychotic disorders. Other risks related to coping with health problems and related treatments are also detailed for both affected individuals and their families. Conclusion The article ends with strategies for addressing psychosocial risks including provision of condition-specific education, enhancement of social support, routine assessment of cognitive abilities, regular mental health screening, and referrals for empirically supported psychiatric and psychological treatments.

Download Full-text