Rabbit Anti-Human Desmoplakin Polyclonal antibody

Background: Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (Mtb). Granuloma is a pathological feature of tuberculosis and is a tight immune cell aggregation caused by Mtb. The main constituent cells are macrophages and their derivative cells including epithelioid macrophages. However, the molecular mechanism of the transition has not been reported. The purpose of this study was to investigate whether early secreted antigenic target of 6-kDa (ESAT6) can induce the transition of bone marrow-derived macrophages (BMDMs) into epithelioid macrophages and its possible molecular mechanism. Methods: The recombinant ESAT6 protein was obtained from E.coli carrying esat6 gene after isopropyl beta-D-thiogalactopyranoside (IPTG) induction. BMDMs were isolated from bone marrow of mice hind legs. Cells viability was detected by Cell Counting Kit 8 (CCK8) assays. The expression levels of mRNA and proteins were detected by qPCR and Western blot, or evaluated by flow cytometry. The expression level of nitric oxide (NO) was measured with a nitric oxide indicator. Results: ESAT6 could significantly induce mRNA and protein expression levels of a group of epithelioid macrophages marker molecules (EMMMs), including E-cadherin, junction plakoglobin, ZO1, desmoplakin, desmo-glein3 and catenin porteins, in BMDMs. These events could be abrogated in macrophage from TLR2 deficiency mice. ESAT6 could also markedly induce iNOS/NO production that could significantly inhibit trimethylation of H3K27 in the cells. ESAT6-induced expressions of epithelioid macrophages marker molecules were significantly inhibited in the presence of H3K27 histone demethylase inhibitor GSK J1. Furthermore, ROS scavenging agent N,N'-Dimethylthiourea (DMTU) could markedly inhibit the transition induced by ESAT6 in macrophages. Conclusion: This study demonstrates that ESAT6 bound with TLR2 can activate iNOS/NO and ROS signalings to reduce the trimethylation of H3K27 resulting in the increment of EMMMs expression that is beneficial to the transition of macrophages into epithelioid macrophages. However, hypoxia can inhibit this transition event. This study has provided new evidence of pathogenesis of granuloma caused by Mtb and also proposed new ideas for the treatment of TB.

Autosomal recessive congenital ichthyosis (ARCI) is a group of disorders characterized by abnormal desquamation of the skin and a disrupted epidermal water barrier. Ichthyin/NIPAL4 gene mutations have been identified in a subgroup of ARCI patients, but the role of ichthyin in epidermis remains elusive. In order to obtain new insights concerning the characteristics of ichthyin and the ARCI pathogenesis, we studied the expression and localization of ichthyin and related epidermal components in cultured keratinocytes and skin sections from patients with Ichthyin mutations and healthy controls. We observed an up-regulation of Ichthyin mRNA levels after in vitro differentiation of keratinocytes from both a patient with Ichthyin mutations and controls. Confocal and electron microscopy analyses of immunolabeled skin sections revealed that ichthyin localizes to desmosomes and keratins in both patients with mutant Ichthyin and controls, with an increased immunolabeling in patients. Nile red lipid analysis of skin sections exposed intra-cellular lipid accumulations in cells of the granular and cornified layers in patients but not in controls, consistent with the pathognomonic lipid membrane structures previously identified in epidermis from patients. Our combined findings indicate that ichthyin is associated with keratins and desmosomes in epidermis and is involved in lipid metabolism, possibly through processing of lamellar bodies. These results provide new clues to the understanding of the epidermal water barrier and the pathogenesis in ARCI.