Additive effect of recombinant Mycobacterium tuberculosis ESAT-6 protein and ESAT-6/CFP-10 fusion protein in adhesion of macrophages through fibronectin receptors

Background/purposeTuberculous granulomas are the sites of interaction between the T cells, macrophages, and extracellular matrix (ECM) to control the infection caused by Mycobacterium tuberculosis (M. tuberculosis). A predominant role of RD-1-encoded secretory proteins, early secreted antigenic target-6 (ESAT-6), and culture filtrate protein-10 (CFP-10) in the formation of granulomas has recently been emphasized. However, the precise molecular events that induce the formation of these granulomatous structures are yet to be elucidated. Macrophages use integrins to adhere to fibronectin (FN) as a major component of the ECM. The major goal of this study was to investigate whether recombinant M. tuberculosis antigens can modulate integrin-mediated macrophage adhesion.MethodsDifferentiated THP-1 cell line was stimulated with recombinant ESAT-6, CFP-10, and ESAT-6/CFP-10 proteins and evaluated for alterations in the expression levels of α5β1 and α4β1 by semiquantitative real-time polymerase chain reaction. The role of these recombinant antigens in the cytoskeleton rearrangement was determined by adhesion assay and immunofluorescent microscopy.ResultsOur data showed that ESAT-6 and ESAT-6/CFP-10 fusion proteins could induce adhesion of macrophages to FN through α4β1 integrin. An increased expression level of α4β1 integrin in comparison with α5β1 integrin in differentiated THP-1 cells was also observed. Results of immunofluorescence studies showed that recombinant proteins-treated THP-1 cells form well-organized stress fibers and focal contacts containing vinculin compared with untreated THP-1 cells.ConclusionIncreased expression level of α4β1 in differentiated THP-1 cells could suggest the important role of α4β1 integrin in adhesion and focal contact formation of macrophages exposed to M. tuberculosis antigens

A review on zeolitic imidazolate frameworks use for crude oil spills cleanup

 Oil spills are a global concern by virtue of their distractive effects on the ecosystem. Many studies have examined the use of porous materials as sorbents for contaminants from different polluted waters. For example, hydrophobic metal organic frameworks, especially zeolitic imidazolate frameworks (ZIFs) with high porosity, have attracted lots of attention. ZIFs are a subclass of metal organic frameworks and display an excellent performance toward oil/water separation compared with other porous materials. Nevertheless, the performance of ZIFs toward oil spills cleanup has not been reviewed. Accordingly, this article overviews the different methods for ZIF preparation, their corresponding structure, and their various applications as sorbents and in particular, recent developments in cleaning up oil spills with meso and micro-porous ZIFs. The investigation of the literatures revealed that the effective parameters on the performance of porous ZIFs are specific surface area, pore diameters of ZIF, and the size of cavities due to interconnecting of ZIF particles. The ZIF-8 with a high surface area of 1408 m2/g and 1384.2 m2/g and adsorption capacity up to 3000 mg/g was studied more than the other ZIF structures. Models predications revealed the maximum adsorption capacity of 6633 mg/g for ZIF-8. Recently, investigations focused on carbonitride foam and melamine sponge as templates of ZIF powder. In comparison with synthesis methods, dip coating as a facial synthesis method was introduced for production and anchoring ZIF particles on the substrate. The recyclability of crude oil and the reusability of the ZIF sorbents are highlighted. Moreover, this article reviews recent developments of ZIFs synthesis, current challenges, and prospects for the use of ZIFs in oil/water separation. The findings of this study can help to better understand widespread applications of ZIFs, effective features of a sorbent, and methods to improve adsorption capacity. As cleaning up oil spills is known as an important issue, this is the first study on ZIFs in particular oil/water separation which provides a summary of researches in a simple form along with recent developments compared to published reviews.Cited as: Shahmirzaee, M., Hemmati-Sarapardeh, A., Husein, M.M., Schaffifie, M., Ranjbar, M. A review on zeolitic imidazolate frameworks use for crude oil spills cleanup. Advances in Geo-Energy Research, 2019, 3(3): 320-342, doi: 10.26804/ager.2019.03.1