Establishment and Evaluation of Intestinal Injury Model of Mouse Acute Graft Versus Host Disease Based on An Organoid Technology / 中国实验血液学杂志

OBJECTIVE@#To establish an intestinal organoid model that mimic acute graft versus host disease (aGVHD) caused intestinal injuries by using aGVHD murine model serum and organoid culture system, and explore the changes of aGVHD intestine in vitro by advantage of organoid technology.@*METHODS@#20-22 g female C57BL/6 mice and 20-22 g female BALB/c mice were used as donors and recipients for bone marrow transplantation, respectively. Within 4-6 h after receiving a lethal dose (8.0 Gy) of γ ray total body irradiation, a total of 0.25 ml of murine derived bone marrow cells (1×107/mice, n=20) and spleen nucleated cells (5×106/mice, n=20) was infused to establish a mouse model of aGVHD (n=20). The aGVHD mice were anesthetized at the 7th day after transplantation, and the veinal blood was harvested by removing the eyeballs, and the serum was collected by centrifugation. The small intestinal crypts of healthy C57BL/6 mice were harvested and cultivated in 3D culture system that maintaining the growth and proliferation of intestinal stem cells in vitro. In our experiment, 5%, 10%, 20% proportions of aGVHD serum were respectively added into the organoid culture system for 3 days. The formation of small intestinal organoids were observed under an inverted microscope and the morphological characteristics of intestinal organoids in each groups were analyzed. For further evaluation, the aGVHD intestinal organoids were harvested and their pathological changes were observed. Combined with HE staining, intestinal organ morphology evaluation was performed. Combined with Alcian Blue staining, the secretion function of aGVHD intestinal organoids was observed. The distribution and changes of Lgr5+ and Clu+ intestinal stem cells in intestinal organoids were analyzed under the conditions of 5%, 10% and 20% serum concentrations by immunohistochemical stainings.@*RESULTS@#The results of HE staining showed that the integrity of intestinal organoids in the 5% concentration serum group was better than that in the 10% and 20% groups. The 5% concentration serum group showed the highest number of organoids, the highest germination rate and the lowest pathological score among experimental groups, while the 20% group exhibited severe morphological destruction and almost no germination was observed, and the pathological score was the highest among all groups(t=3.668, 4.334,5.309,P<0.05). The results of Alican blue staining showed that the secretion function of intestinal organoids in serum culture of aGVHD in the 20% group was weaker than that of the 5% group and 10% of the organoids, and there was almost no goblet cells, and mucus was stainned in the 20% aGVHD serum group. The immunohistochemical results showed that the number of Lgr5+ cells of intestinal organoids in the 5% group was more than that of the intestinal organoids in the 10% aGVHD serum group and 20% aGVHD serum group. Almost no Clu+ cells were observed in the 5% group. The Lgr5+ cells in the 20% group were seriously injuried and can not be observed. The proportion of Clu+ cells in the 20% group significantly increased.@*CONCLUSION@#The concentration of aGVHD serum in the culture system can affect the number and secretion function of intestinal organoids as well as the number of intestinal stem cells in organoids. The higher the serum concentration, the greater the risk of organoid injury, which reveal the characteristics of the formation and functional change of aGVHD intestinal organoids, and provide a novel tool for the study of intestinal injury in aGVHD.

Serum interleukin-2 receptor α as a clinical biomarker in patients with systemic lupus erythematosus / 北京大学学报(医学版)

OBJECTIVE@#To investigate the clinical relevance of serum interleukin-2 receptor α (IL-2Rα) in patients with systemic lupus erythematosus (SLE).@*METHODS@#One hundred and seven SLE patients and 39 healthy controls with comparable age and gender were recruited at Peking University People's Hospital from January 2019 to December 2020. Complete clinical data in 107 SLE patients at baseline and follow-up were collected. SLE disease activity index 2000 (SLEDAI-2K) was used to assess the disease activity of the SLE patients. The serum level of IL-2Rα in the SLE patients and healthy controls was measured using enzyme-linked immunosorbent assay (ELISA). The association between serum IL-2Rα and clinical and laboratory parameters was investigated. Mann-Whitney U test or t test, Chi-square test and Spearman correlation were used for statistical analysis.@*RESULTS@#The serum IL-2Rα levels were significantly higher in the SLE patients [830.82 (104.2-8 940.48) ng/L], compared with those in the healthy controls [505.1 (78.65-1 711.52) ng/L] (P < 0.001). Association analysis showed that the increased serum IL-2Rα was positively associated with SLEDAI-2K scores and anti-nucleosome antibody (r=0.357, P < 0.001; r=0.25, P=0.027, respectively). Thirty-six of 107 (33.6%) SLE patients had lupus nephritis. Serum IL-2Rα levels were significantly higher in the patients accompanied with lupus nephritis [1 102.14 (126.52-8 940.48) ng/L] than in the patients without lupus nephritis [743.89 (104.19-4 872.06) ng/L] (P=0.032). The patients in the high IL-2Rα group had more lupus nephritis compared with those in the low IL-2Rα group (40.8% vs. 19.4%, P=0.031). Meanwhile, SLEDAI-2K scores were found significantly higher in the high IL-2Rα group than in the low IL-2Rα group [10 (3-21) vs. 7 (3-16), P=0.001]. With the improvement of disease activity in the SLE patients after conventional treatments, serum levels of IL-2Rα [1 119.1 (372.25-2 608.86) ng/L] in the week 12 decreased significantly compared with the baseline [1 556.73 (373.08-8 940.48) ng/L] (P=0.042).@*CONCLUSION@#Serum IL-2Rα may be used as a biomarker of disease activity in patients with SLE. There is certain correlation between serum IL-2Rα and renal involvement in SLE.