Expression of schistosomal cathepsin l1 in Escherichia coli and evaluation of its protective capacity in an animal challenge

Patrícia A Miyasato ,Patrícia Antônia Estima Abreu ,Celso Raul Romero Ramos ,Paulo Lee Ho ,Waldely O Dias ,Carlos Nascimento ,Toshie Kawano

doi:10.1590/s1678-91992009000200011

Patrícia A Miyasato , Patrícia Antônia Estima Abreu + Show 5 more

Open Access

https://doi.org/10.1590/s1678-91992009000200011

Copy DOI

Abstract

Schistosomes utilize proteinases to accomplish several activities such as tissue penetration, tissue digestion and evasion of host immune responses. Cathepsin L is a cysteine proteinase of the papain superfamily detected in their gut lumen which indicates that this enzyme contributes to the proteolysis of ingested hemoglobin. Due to the roles played in the schistosome biology, proteolytic enzymes are considered potential targets for developing and guiding antischistosomal therapies. In the present work, the cathepsin L1 cDNA coding of Schistosoma mansoni was cloned into the pAE vector that provides high-level expression of heterologous proteins in Escherichia coli. The recombinant protein was expressed as inclusion bodies, purified under denaturing conditions through nickel-charged chromatography and used for experimental animal vaccination. ELISA was performed with the pooled sera. Although this protein was shown to be immunogenic, mice immunized with three doses of recombinant protein plus aluminum hydroxide as adjuvant were not protected against S. mansoni infection.

Highlights

Schistosomiasis remains a major public health problem in developing countries
The results presented showed the expression of the recombinant SmCL1 protein in Escherichia coli BL21 SI strain, with high final yield of purified protein
The expressed protein displayed six histidine residues at the carboxy terminus of the recombinant protein, which allowed its purification through affinity chromatography on nickel-charged beads

Summary

Introduction

Schistosomiasis remains a major public health problem in developing countries. Despite two decades of widespread chemotherapy with safe and effective drugs, the number of individuals with schistosomiasis remains high [2]. The construction of water resources and agricultural requirements for human development have led to increasing transmission of schistosomiasis [3]. The risk of reintroduction of the disease into a treated area, where there are irrigation projects and population migration, must be taken into account [4, 5]. Supplying efficient treatment that covers all parts of an endemic area can make chemotherapy an expensive and impractical alternative [7]. Several factors make schistosomiasis vaccine development an advantageous option:

Objectives

Methods

Results

Conclusion