Indoleamine 2,3-dioxygenase is dispensable for the immunomodulatory function of stem cells from human exfoliated deciduous teeth

Objective: In this study, we sought to better understand the immunoregulatory function of stem cells derived from human exfoliated deciduous teeth [SHED]. We studied the role of the interferon gamma [IFN-gamma]-indoleamine 2,3-dioxygenase [IDO]-axis in immunoregulation of SHED compared to bone marrow derived mesenchymal stem cells [BMMSCs] under the same conditions

Materials and Methods: In this cross-sectional study, recently isolated human T cells were stimulated either by mitogen or inactivated allogeneic peripheral blood mononuclear cells [PBMCs]. These T cells were subsequently co-cultured with, either SHED or BMMSCs in the presence or absence of 1-methyl-tryptophan [1-MT] or neutralizing anti-human-IFN-gamma antibodies. In all co-cultures we evaluated lymphocyte activation as well as IDO activity

Results: SHED, similar to conventional BMMSCs, had anti-proliferative effects on stimulated T cells and reduced their cytokine production. This property of SHED and BMMSCs was changed by IFN-gamma neutralization. We detected IDO in the immunosuppressive supernatant of all co-cultures. Removal of IDO decreased the immunosuppression of BMMSCs

Conclusion: SHED, like BMMSCs, produced the IDO enzyme. Although IFN-gamma is one of inducer of IDO production in SHED, these cells were not affected by IFN-gamma in the same manner as BMMSCs. Unlike BMMSCs, the IDO enzyme did not contribute to their immunosuppression and might have other cell-type specific roles

Cloning and expression of Brucella cyclic beta-1, 2 glucan transporter gene [cgt]

Brucellosis is an important cosmopolitan infection disease caused by organisms belonging to the genus Brucella. The cgt gene [cyclic beta-1, 2 glucan transporter gene] is a virulent factor in Brucella genus. The present study was conducted with the aim of cloning and expression of Brucella cgt gene. Brucella melitensis cgt gene was amplified from extracted chromosomal DNA by PCR, then PCR product was cloned into pTZ57R and subcloned into pGEMEX-1 expression vector, then expressed in JM109 E. coli strain. Recombinant protein was confirmed by western blot analysis using patient's serum. The PCR product was cloned in pTZ57R plasmid via T/A cloning method. Recombinant plasmid was digested by Band HI and SacI restriction enzymes, the released band was purified and subcloned into pGEMEX-1 expression vector. Then, sample cells were lysed using lyses buffer and sonicated, then electrophoresed on SDS-PAGE. Protein bands were transferred on nitrocellulose membrane and reacted by patient's serum and detected by FIRP conjugated-anti human antibody. We cloned and expressed Brucella abortus cyclic beta-1, 2-glucan transporter gene [cgt] which is an important agent in brucellosis. Using cgt gene mutant may be an effective way for inhibiting or decreasing the pathogenicity of bacteria