This study addresses the fabrication of an extracellular matrix material of the acellular sheep periosteum and the systematic evaluation of its biocompatibility to explore its potential application in guided bone regeneration. Sheep periosteum was harvested and decellularized by a combined decellularization protocol. The effectiveness of cell removal was proved and residual α-Gal antigen was also quantitatively detected. Then, mouse MC3T3-E1 cells were seeded onto the acellular periosteum. A scanning electron microscope (SEM) was used to record the whole process of cell adhesion. The CCK-8 assay suggested that the acellular periosteum not only had zero toxic effect on pre-osteoblasts, but played a positive role in cell proliferation. We also tested whether the acellular periosteum possesses favorable osteogenesis induction activity using an alkaline phosphatase (ALP) assay and a quantitative real-time PCR (Col I, Runx2, OCN) assay. An in vivo study of a subcutaneous implantation test using Sprague Dawley (SD) rats was performed to detect the changes in IL-2, IFN-γ and IL-4 in serum and elucidate the host's local response to acellular periosteum through hematoxylin and eosin (HE) and immunohistochemical staining. The results show that acellular sheep periosteum did not elicit a severe immunogenic response via the Th1 pathway, unlike fresh sheep periosteum. In conclusion, acellular sheep periosteum possesses favorable biocompatibility to be employed for guided bone regeneration.
The 5-fluorouracil/leucovorin plus oxaliplatin (FOLFOX) regimen is the standard first-line treatment for metastatic colorectal cancer (mCRC), however, the optimal second-line regimen for KRAS wild-type mCRC patients is still investigational. In this study, we aimed to determine the clinical efficacy and safety of CMAB009 plus irinotecan compared to irinotecan-only as a second-line regimen for treating KRAS wild-type mCRC patients. Patients with KRAS wild-type mCRC who had previously failed to respond to FOLFOX treatment were randomly assigned in a 2:1 ratio, to receive CMAB009 plus irinotecan or irinotecan-only. Patients receiving irinotecan-only were permitted to switch to CMAB009 therapy on disease progression and were grouped as the sequential-CMAB009 arm. The primary endpoints were overall response rate (ORR) and median progression-free survival (PFS). The secondary endpoints were median overall survival (OS), disease control rate (DCR), clinical benefit rate (CBR), and duration of response (DOR). The CMAB009 plus irinotecan arm demonstrated significantly improved ORR (33.2% vs. 12.8%; P < 0.001) and longer median PFS (169 days vs. 95 days; P < 0.001) as compared to the irinotecan-only arm. Patients receiving CMAB009 plus irinotecan also demonstrated improved DCR (80.1% vs. 65.2%, P < 0.001), CBR (30.0% vs. 14.6%, P < 0.001), and DOR (210 days vs. 109 days; P < 0.001) as compared to irinotecan-only. However, patients treated with CMAB009 had an increased risk of skin rash (66.9% vs. 5.5%, P < 0.001) and paronychia (9.8% vs. 0.0%, P < 0.001). Anti-drug antibodies (ADA) were detected in 3.6% of patients, and only 0.9% of patients who received CMAB009 experienced hypersensitivity reactions. In patients receiving sequential-CMAB009 therapy after failure with irinotecan, their median PFS was 84 days (95% CI 65 to 113 days). The median OS was 425 days for patients receiving CMAB009 plus irinotecan and 401 days for those with sequential-CMAB009 (P = 0.940). Treatment with CMAB009 plus irinotecan was found to be a superior second-line regimen in comparison to irinotecan-only in KRAS wild-type mCRC patients. Further, switching to CMAB009 can be considered as an efficient third-line of treatment after treatment failure with second-line irinotecan-only. Trial registration ClinicalTrials.gov: NCT01550055, retrospectively registered on March 9, 2012.
Food allergies can alter the gut microbiome composition, increasing the risk of conditions such as ankylosing spondylitis (AS).To identify the association between specific allergens and AS, we investigated the differences in the serum levels of 14 food antigen-specific immunoglobulin (Ig) G between AS patients and healthy participants. The association between the levels of these antibodies and disease activity was assessed by measuring the inflammatory marker C-reactive protein (CRP).We enrolled 75 AS patients and 78 healthy controls who had undergone antigen-specific IgG tests in West China Hospital between January 2015 and October 2017, and performed enzyme-linked immunosorbent assays for specific IgG against 14 food allergens: rice, egg, mushroom, milk, pork, chicken, beef, crab, codfish, corn, soybean, tomato, shrimp, and wheat. The following tests were used to analyze differences between AS patients and healthy controls: χ test for sex, and a 2-tailed Student t-test or Mann-Whitney U test based on the results of Levene test for age and IgG levels. Correlations between IgG and CRP levels were calculated using a Spearman's correlation.AS patients had significantly higher serum levels of beef-, crab-, and pork-specific IgG than did healthy participants. In addition, the serum levels of pork-specific IgG were significantly and positively correlated with CRP.These results suggest that α-Gal, the predominant natural antigen in mammalian red meat, might play a potential role in the pathogenesis of AS, and therefore, AS patients should exclude such allergenic foods, including beef, crab and pork, from their daily diet.
In order to address the disadvantage of rapid degradation and serious immune response of bladder acellular matrix (BAM) tissues in clinical application, in this study, oxidized carboxymethyl cellulose (DCMC) was developed to replace glutaraldehyde (GA), a most common synthetic crosslinking reagent in clinical practice, to fix BAM tissues for lower cytotoxicity. The aim of this work was to evaluate feasibility of DCMC as a crosslinking reagent for BAM fixation and developing DCMC fixed-BAM (D-BAM) tissues for tissue engineering. For the preparation of DCMC, the results showed that when DCMC was prepared using a specific concentration of sodium periodate solution (the mass ratio of NaIO/CMC is 1 : 1) and a specific reaction time (4 hours), its cytotoxicity was the lowest and its fixation effect was better. The critical crosslinking characteristics and cytocompatibility of optimum D-BAM tissues were also investigated. The results demonstrated that DCMC-fixation (especially 30 mg ml DCMC-fixation) not only formed stable cross-linking bonds but also preserved well the original ultrastructure of the BAM tissues, which simultaneously increased the mechanical strength and capacity of the enzymatic hydrolytic resistance. The DCMC-fixation could also reduce the expression of α-Gal in BAM tissues and preserve the useful growth factors such as GAGs, KGF and TGF-β in bladder tissues. In addition, 30 mg ml D-BAM tissues had excellent cytocompatibility. Moreover, it could stimulate the secretion of PDGF and EGF from seeded bladder transitional epithelial cells (BTECs), which is a critical feature for further re-epithelialization. Its anti-calcification ability was also prominent, which is necessary in bladder repair. The present studies demonstrated that DCMC could be a potential biological crosslinking agent for BAM fixation due to its excellent crosslinking effects, and the D-BAM tissues were suitable to be used as a substitute for the bladder due to their resistance to enzymatic degradation, anticalcification and cytocompatibility.
Sichuan da xue xue bao. Yi xue ban = Journal of Sichuan University. Medical science edition •
To develop a method for quantitative assay of alpha-Gal on pig cell surface. After centrifugation of the anticoagulated blood samples, the white blood cell layer was collected for addition of FITC-BSIB4 and analysis using FCM as well as Laser Scan Confocal Microscope (Bio-Rad). With human blood group B as negative control, and mouse myeloma SP2/0 cells as positive control. the peripheral blood cells of two Chinese pigs were all positive, there were about 9.16 x 10(5) alpha-Galactosyl epitopes expressed on the cell-membrane of granulocytes 1.37 x 10(5) on the monocytes of Banna Minipig Inbred Line (BMI), and 1.16 x 10(6) on the granulocyte and 2.45 x 10(5) on the monocytes of Sichuan White Pig (SWP). The levels of alpha-Galactosyl expression on the surface of blood cells in BMI and SWP differed in various cells, the sequence from high to lower expression levels being on the platelets, granulocytes, monocytes, erthrocytes in each species of pig. The method is useful for quantitative assay of alpha-Gal on pig cell surface, and the assay may be used for alpha-Gal for on-site large-scaled screening of living pigs.
