Romidepsin (FK228) improves the survival of allogeneic skin grafts through downregulating the production of donor-specific antibody via suppressing the IRE1α-XBP1 pathway / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Antibody-mediated rejection (AMR) is one of the major causes of graft loss after transplantation. Recently, the regulation of B cell differentiation and the prevention of donor-specific antibody (DSA) production have gained increased attention in transplant research. Herein, we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin (FK228) on DSA. The survival of grafted skins was monitored daily. The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry. Then, we isolated and purified B cells from B6 mouse spleens in vitro by magnetic bead sorting. The B cells were cultured with interleukin-4 (IL-4) and anti-clusters of differentiation 40 (CD40) antibody with or without FK228 treatment. The immunoglobulin G1 (IgG1) and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay (ELISA). Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting were conducted to determine the corresponding levels of messenger RNA (mRNA) and protein expression in cultured cells and the recipient spleens. The results showed that FK228 significantly improved the survival of allogeneic skin grafts. Moreover, FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1 (HADC1) and HDAC2 and the upregulation of the acetylation of histones H2A and H3. It also inhibited the differentiation of B cells to plasma cells, decreased the transcription of positive regulatory domain-containing 1 (Prdm1) and X-box-binding protein 1 (Xbp1), and decreased the expression of phosphorylated inositol-requiring enzyme 1 α (p-IRE1α), XBP1, and B lymphocyte-induced maturation protein-1 (Blimp-1). In conclusion, FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway. Thus, FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.

Localization and therapeutic effect of bone marrow hematopoietic cell transplantation in rat model of liver fibrosis / 临床肝胆病杂志

ObjectiveTo investigate the localization and therapeutic effect of allogeneic bone marrow hematopoietic stem cell (HSC) transplantation in the rat model of liver fibrosis induced by carbon tetrachloride (CCl4). MethodsBone marrow HSCs from allogeneic Sprague-Dawley (SD) rats were isolated and cultured in vitro and labeled with 5-bromo-2′-deoxyuridine (BrdU) before transplantation. Eighteen female SD rats were randomly and equally divided into groups A, B, and C. A female rat model of liver fibrosis was established using CCl4. The rats in group A were injected with HSC-containing suspension through the caudal vein in the fourth week after CCl4 injection, while the rats in groups B and C were injected with normal saline through the caudal vein. In the eighth week, blood samples were taken from all groups. Then all rats were sacrificed, and the liver, pancreatic, and stomach tissues were collected to examine the localization of HSC and evaluate the therapeutic effect of HSC on liver damage. The double-blind method was used to statistically analyze experimental results. Comparison of continuous data between these groups was made by analysis of variance, and pairwise comparison was made by SNK-q test; comparison of categorical data between these groups was made by Kruskal-Wallis H test, and pairwise comparison was made by Nemenyi test. ResultsGroup A showed significantly improved histopathology compared with group B, while groups A and C showed approximately the same histological findings. There were significant differences in classification of liver fibrosis between groups A, B, and C (χ2=13.14, P=0.001), and groups A and C had significantly lower grades of liver fibrosis than group B (both P＜0.05). In group A, BrdU-positive cells were detected in the liver tissues of all rats, but no positive cells were detected in the pancreatic and stomach tissues; no BrdU-positive cells were detected in groups B and C. Compared with group B, groups A and C had significantly lower alanine aminotransferase and aspartate aminotransferase levels but a significantly higher albumin level (all P＜0.05). ConclusionAllogeneic HSC can be localized in the rat model of liver fibrosis and reverse the liver damage.