Biology subjects

Rung, S.

Publications and source records attributed to Rung, S..

3 recordsLinked to original sources

bioRxiv2020

EGCG-modified bone graft to modulate the recruitment of M1 macrophage and alleviate the forming of fibrous capsule

In response to current trends in the modification of guided bone regeneration (GBR) materials, we aimed to build upon our previous studies on epigallocatechin-3-gallate (EGCG) by immersing a commonly used bone graft primarily composed of hydroxyapatite (HA) in EGCG solution, expecting to obtain superior bone-material integration after implantation. Bone grafts are commonly used for bone repair, in which the bone extracellular matrix is stimulated to promote osteogenesis. However, due to its pro-fibrosis effect, this osteoconductive material commonly exhibits implant failure. In addition to providing a basic release profile of EGCG-modified bone graft (E-HA) to clarify the relationship between this material and the environment, we have examined the integration effect via subcutaneous implantation experiments. In this manner, we have assessed the aggregation of pro-inflammatory macrophages, initial angiogenesis, the formation of fibrous capsules, and an enhanced cell viability observed in cultured RAW 264.7 cells. Among these results, we focus on pro-inflammatory macrophages due to their close relationship with fibrosis, which is the most important process in the immune response. Immunofluorescent staining results showed that E-HA substantially compromised the formation of fibrous capsules in hematoxylin-eosin-stained sections, which exhibited less pro-inflammatory macrophage recruitment; meanwhile, the cell viability and primary angiogenesis were improved. This work lays the foundation for future studies on GBR.

immunology↗

bioRxiv2020

Application of EGCG modified EDC/NHS cross-linked extracellular matrix to promote macrophage adhesion

Though chemically cross-linked by EDC/NHS endows collagen membrane with promising mechanical properties, it is not conducive to modulation of foreign body reaction (FBR) after implantation or guidance of osteogenesis. In our previous research, we have found that macrophages have a strong regulatory effect on tissue and bone regeneration during FBR, and EGCG modified membranes could adjust the recruitment and phenotypes of macrophages. Accordingly, we develop the EGCG-EDC/NHS membranes, prepared with physically immersion, while the surface morphology of the membrane was observed by SEM, the biological activity of collagen was determined by FTIR, the activity and adhesion of cell culture in vitro, angiogenesis and monocyte/macrophage recruitment after subcutaneous implantation, etc. are characterized. It could be concluded that EGCG-EDC/NHS collagen membrane is hopeful to be used in implant dentistry for it not only retains the advantages of the collagen membrane itself, but also improves cell viability, adhesion and vascularization tendency. However, the mechanism that lies in the regenerative advantages of such membrane needs further exploration, but it is certain that the differences in surface morphology can have a significant impact on the reaction between the host and the implant, not to mention macrophage in bone regeneration.

immunology↗

bioRxiv2020

Consideration of macrophage phenotypes under biomaterials mediated host defense process

Culturing macrophage in vitro is an important means to understand its reaction towards co-culture substances. However, the source of macrophages can be either purchased from specific cell line or extracted from bone marrow as differentiated macrophages. In order to assure the precision, when adopting extracted primary cell, screening in advance will be prominent before any processes to avoid results reserving that of non-macrophages. Here, we perform single-cell sequencing on open wound of skin in mice and focusing on the secreted proteins and surface markers related to traditional macrophage phenotypes (M1/M2) to ensure the importance of screening. The expression of CAMP when macrophages fight against candida albicans is another target to see its relationship with current classification. And results showed that identifying its phenotype without screening macrophages will far from the exact situation, and the expression of CAMP cannot be carried out by the traditional M1 and M2 macrophage. Thus, determining phenotype of macrophages based on function would be a promising way.

immunology↗