Potential therapeutic options for celiac Disease: An update on Current evidence from Gluten-Free diet to cell therapy

Celiac disease (CD) is a chronic autoimmune enteropathy and multifactorial disease caused by inappropriate immune responses to gluten in the small intestine. Weight loss, anemia, osteoporosis, arthritis, and hepatitis are among the extraintestinal manifestations of active CD. Currently, a strict lifelong gluten-free diet (GFD) is the only safe, effective, and available treatment. Despite the social burden, high expenses, and challenges of following a GFD, 2 to 5 percent of patients do not demonstrate clinical or pathophysiological improvement. Therefore, we need novel and alternative therapeutic approaches for patients. Innovative approaches encompass a broad spectrum of strategies, including enzymatic degradation of gluten, inhibition of intestinal permeability, modulation of the immune response, inhibition of the transglutaminase 2 (TG2) enzyme, blocking antigen presentation by HLA-DQ2/8, and induction of tolerance. Hence, this review is focused on comprehensive therapeutic strategies ranging from dietary approaches to novel methods such as antigen-based immunotherapy, cell and gene therapy, and the usage of nanoparticles for CD treatment.

Production of CFTR Mutant Gene Model by Homologous Recombination System

OBJECTIVE

The most common mutation in cystic fibrosis (CF), (ΔF508-CFTR), results in impaired protein maturation, folding and transportation to the surface of the cell. As a consequence of impaired protein maturation and/or transport from the extracellular matrix to the cell, different systems are influenced, including gastrointestinal system and glandular system, reproductive system and respiratory systems. CF models are essential tools to provide further knowledge of CF pathophysiology. With this aim, we designed a transgenic CF model based on the homologous recombination (HR) system.

MATERIALS AND METHODS

In this experimental study, a specifically designed construct containing the CFTR gene with F508del was cloned into a PTZ57R cloning vector and then the construct was transformed into the male pronucleus by microinjection after in vitro fertilization (IVF). Then the rates of blastocyst formation and embryonic development at 72 hours after IVF, were evaluated using the inverted microscope and the insertion of the construct was approved by polymerase chain reaction (PCR) method.

RESULTS

The CFTR gene was successfully cloned into the PTZ57R cloning vector and overall, from 22 injected cells, 5 blastocysts were observed after pronuclear injection of the CFTR gene construct. PCR verification of the blastocyst with CFTR-specific primers represented complete recombination of CFTR into the mouse genome.

CONCLUSION

For the first time we designed a unique genome construction that can be detected using a simple PCR method. The pronuclear injection was performed for the transformation of the genome construct into the male pronuclei using microinjection and the development of zygote to the blastocyst stage has been observed following transgenesis.

Using recombinant Chlamydia trachomatis OMP2 as antigen in diagnostic ELISA test

BACKGROUND AND OBJECTIVES

The obligate intracellular bacterium Chlamydia trachomatis causes sexually transmissible diseases in human. Timely and sensitive detection of this pathogen is very important. There are many cross-reactions in bacteriological and serological methods in detection of this type of pathogens. The aim of this study was to achieve a more specific antigen for serological tests.

MATERIALS AND METHODS

Blood samples were taken from 192 women with suspected chlamydial infection and sera were isolated. ELISA plate wells were coated with recombinant C. trachomatis OMP2 as antigen. Cut-off system was determined with 40 negative sera. The final results of this research were compared with Euroimmun commercial kit.

RESULTS

The ELISA system cut-off was calculated at 0.27 using negative sera samples. ODs of positive samples were higher than 0.27 and negative samples were lower than it. We obtained 30 samples (15.62%) as positive and 162 cases (84.37%) as negative. Sensitivity and specificity of the recombinant antigen were 90% and 86%, respectively. This antigen showed no cross-reactivity with sera of patients infected with Hydatid cyst, HCV, Epstein barr virus, HBV, Helicobacter pylori, Toxoplasma gondii, Cytomegalovirus, Mycoplasma, Measles and Varicella zoster virus.

CONCLUSION

The sensitivity and specificity of rOMP2 in ELISA for detection of C. trachomatis were 90% and 86%, respectively. Though the sensitivity was higher than results of Euroimmun commercial kit, its specificity was calculated lower than reference kit.

Recombinant SAG1 Antigen to Detect Toxoplasma gondii Specific Immunoglobulin G in Human Sera by ELISA Test

BACKGROUND

Although some serological tests for the detection of Toxoplasma gondii-specific immunoglobulin are commercially available, better diagnostic tools are needed. The aim of present study was to evaluate the usefulness of the recombinant Toxoplasma gondii SAG1 antigen for the recognition of toxoplasmosis by ELISA.

METHODS

This study was conducted in Cellular and Molecular Biology Research Centers, Shahid Beheshti University, M.C., Tehran, Iran in 2008-2009. Surface antigen 1 (SAG1), a tachyzoite stage-specific protein, was subcloned into an expression vector and was subsequently transformed into BL21 (DE3) pLysS competent bacterial cells. After inducing expression of the recombinant antigen, the protein product was purified using Ni-affinity chromatography. The immunoreactivity of recombinant SAG1 (rSAG1) was analyzed by SDS-PAGE and western blotting. The reactivity of the rec-SAG1 protein was evaluated using an ELISA.

RESULT

Sensitivity and specificity of the generated recombinant-ELISA (rec-ELISA) compared to a commercially available ELISA (com-ELISA) were 88.4% and 88%, respectively.

CONCLUSION

Recombinant SAG1 produced in E. coli is a promising antigen that can be used in diagnostic assays for the detection of specific antibodies against T. gondii.

Alterations of BDNF and NT-3 genes expression in the nucleus paragigantocellularis during morphine dependency and withdrawal

Locus coeruleus (LC) plays a key role in opioid dependence and withdrawal. Chronic morphine administration induces neurochemical adaptations in the noradrenergic system. The nature of signal responsible for opiate-induced adaptations of noradrenergic neurons in LC is not well defined. Neurotrophins-signaling pathways such as brain derived neurotrophic factor (BDNF) and Neurotrophin-3 (NT-3) play a key role for regulating the noradrenergic response of LC neurons to opiates. The nucleus paragigantocellularis (PGi) is one of the two major afferents to LC. The present study was designed to evaluate the expression of BDNF and NT-3 in the context of opiate dependence and withdrawal in PGi. Such data are important because they could reveal the role of PGi as an additional source of BDNF and NT-3 in the neurochemical plasticity of LC neurons. Opiate dependence was induced by a progressive intraperitoneal treatment of morphine. In morphine dependent group PGi nucleus was extracted for gene expression assay 6h after the last injection of morphine. In spontaneous withdrawal, rats received the same chronic treatment as morphine group. PGi was extracted for gene expression assay 24, 48 and 72 h after the last injection of morphine. PGi nucleus was assayed for the expression of BDNF and NT-3 using semi-quantitative RT-PCR normalized to beta-actin gene expression. Results showed that chronic administration of morphine significantly increased BDNF and NT-3 gene expression in PGi. In spontaneous withdrawal, BDNF/NT-3 genes expression were high in comparison to control group. It seems that BDNF/NT-3 -signaling pathway originating from PGi is essential for opiate-induced adaptations of the LC neurons.