An expression vector pET-28a-mGM-CSF-X10-βhCGCTP37 plasmid containing the βhCG and mGM-CSF gene was designed and constructed. The fusion protein was induced by lactose and purified by ammonium sulfate precipitation and DEAE-cellulose anion exchange column. Then dendritic cells(DC)in C57BL/6J mice were extracted and sensitized by the fusion protein to obtain DC vaccine. The DC vaccine was inoculated to C57BL of / 6J mice with prostate cancer RM-1. The results indicated that the anti-tumor effects of DC group and DC combined with paclitaxel(DP)group were superior to that of paclitaxel(Pac)group(P< 0. 01), and the anti-tumor effect of DP group was better than that of DC group. Thus, the constructed DC vaccine can inhibit the growth of prostate cancer, and have synergistic anti-tumor when used with paclitaxel.

Objective:To study the in vitro construction of functional and self-renewing cartilage organoids based on cartilage acellular extracellular matrix (ECM) microcarriers.Methods:Fresh porcine articular cartilage was taken. The merely crushed cartilage particles were set as natural cartilage group and ECM microcarriers of appropriate particle size, which were prepared by the acellular method of combining physical centrifugation and chemical extraction, were set as microcarrier group. Cartilage organoids were constructed by loading human umbilical cord mesenchymal stem cells (hUCMSCs) and human chondrocytes (hCho) with a ratio of 3∶1 with microcarriers through a rotating bioreactor. The organoids with different induction times were divided into 0-, 7-, 14-, and 21-day induction groups. The cell residues of the microcarrier group and natural cartilage group were evaluated by 4′, 6-diaminidine 2-phenylindole (DAPI) fluorescence staining and DNA quantitative analysis. The retention of microcarrier components was observed by Safranin O and toluidine blue stainnings, and the collagen and glycosaminoglycan (GAGs) levels in the microcarrier group and the natural cartilage group were determined by colorimetric method and dimethyl-methylene blue (DMMB) method. The microcarriers were further characterized by scanning electron microscopy and energy dispersive spectroscopy. The hUCMSCs cultured with Dulbecco′s Modified Eagle′s Medium (DMEM) supplemented with fetal bovine serum (FBS) in a volume fraction of 10% was used as the control group and the hUCMSCs cultured with the microcarrier extract was used as the experimental group. Subgroups of hUCMSCs cultured at 3 time points: 1, 3 and 5 days were set up in the two groups separately. Cell Counting Kit 8 (CCK-8) was used to detect the biocompatibility of the two groups. The cellular activity of the organoids of the 0-, 7-, 14-, and 21-day induction groups was detected by live/dead staining and the self-renewal ability of the cartilage organoids of the 14-day induced group was identified by Ki67 fluorescence staining. The organoids of the 7-, 14-, and 21-day induction groups were detected by RT-PCR in terms of the expression levels of chondrogenesis-related marker aggrecan (ACAN), type II collagen (COL2A1), SRY-related high mobility group-box gene-9 (SOX9), cartilage hypertrophy-and mineralization-related marker type I collagen (COL1A1), Runt-related transcription factor-2 (RUNX2), and osteocalcin (OCN). Colorimetric and DMMB assays were performed to determine the ability of organoids in the 0-, 7-, 14-, and 21-day induction groups to secrete collagen and GAGs.Results:The results of DAPI fluorescent staining showed that the natural cartilage group had a large number of nuclei while the microcarrier group hardly had any nuclei. The DNA content of the microcarrier group was (7.8±1.8)ng/mg, which was significantly lower than that of the natural cartilage group [(526.7±14.7)ng/mg] ( P<0.01). Saffranin O and toluidine blue staining showed that the microcarrier was dark- and uniform-colored and it kept a lot of cartilage ECM components. The collagen and GAGs contents of the microcarrier group were (252.9±1.4)μg/mg and (173.4±0.8)μg/mg, which were significantly lower than those of the natural cartilage group [(311.9±2.2)μg/mg and (241.3±0.7)μg/mg] ( P<0.01). Scanning electron microscopy showed that the surface of the microcarriers had uneven and interleaved collagen fiber network. The results of energy spectrum analysis showed that elements C, O and N were evenly distributed in the microcarriers, indicating that the composition of the microcarrier was uniform. The microcarrier had good biocompatibility and there was no statistical significance in the results of CCK-8 test between the control group and the experimental group after 1 and 3 days of culture ( P>0.05). After 5 days of culture, the A value of the experimental group was 0.53±0.02, which was better than that of the control group (0.44±0.03) ( P<0.05). In the 0-, 7-, 14-, and 21-day induction groups, hUCMSCs and hCho were attached to the surface of the microcarriers, with good cellular activity, and the live/death rates were (70.6±1.1)%, (80.5±0.6)%, (94.5±0.9)%, and (90.8±0.5)% respectively ( P<0.01). There were a large number of Ki67 positive cells in cartilage organoids. RT-PCR showed that the expression levels of ACAN, COL2A1, SOX9, COL1A1, RUNX2 and OCN were 1.00±0.09, 1.00±0.24, 1.00±0.18, 1.00±0.03, 1.00±0.06 and 1.00±0.13 respectively in the 7-day induction group; 4.16±0.28, 5.09±1.25, 5.65±1.05, 0.47±0.01, 1.68±0.02 and 0.21±0.06 respectively in the 14-day induction group; 13.42±0.92, 3.07±0.21, 1.84±1.08, 2.72±0.17, 2.91±0.18 and 3.32±1.20 respectively in the 21-day induction group. Compared with the 7-day induction group, the expression levels of ACAN, COL2A1, SOX9 and RUNX2 in the 14-day group were increased ( P<0.05), but COL1A1 expression level was decreased ( P<0.05), with no significant difference in OCN expression level ( P>0.05). Compared with the 7-day induction group, the expression levels of ACAN, COL1A1 and RUNX2 in the 21-day induction group were significantly increased ( P<0.01), with no significant differences in the expression levels of COL2A1, SOX9 and OCN ( P>0.05). Compared with the 14-day induction group, the expression levels of ACAN, COL1A1, RUNX2 and OCN in the 21-day group were increased ( P<0.05 or 0.01), with no significant difference in the expression level of COL2A1 ( P>0.05), but the expression level of SOX9 was decreased ( P<0.05). The contents of collagen in 0-, 7-, 14-and 21-day induction groups were (219.15±0.48)μg/mg, (264.07±1.58)μg/mg, (270.83±0.84)μg/mg and (280.01±0.48)μg/mg respectively. The GAGs contents were (171.18±1.09)μg/mg, (184.06±1.37)μg/mg, (241.08±0.84)μg/mg and (201.14±0.17)μg/mg respectively. Compared with the 0-day induction group, the contents of collagen and GAGs in 7-, 14-, and 21-day induction groups were significantly increased ( P<0.01), among which the content of collagen was the lowest in 7-day induction group ( P<0.01) but the highest in the 21-day induced group ( P<0.01); the content of GAGs was the lowest in the 7-day induced group ( P<0.01) but the highest in the 14-day induction group ( P<0.01). Conclusions:The microcarriers prepared by combining physical and chemical methods are decellularized successfully, with more matrix retention, uniform composition and on cytotoxicity. By loading microcarriers with hUCMSCs and hCho, cartilage organoids are successfully constructed in vitro, which are characterized by good cell activity, self-renewal ability, strong expression of genes related to chondrogenesis and secretion of collagen and GAGs. The cartilage organoids constructed at 14 days of induction have the best chondrogenic activity.

BACKGROUND:There is no consensus on the optimal bone tunnel position in the lateral clavicle,which guides coracoclavicular ligament reconstruction.Postoperative complications such as enlargement of the lateral clavicle bone tunnel,bone osteolysis,clavicle fracture,and failure of internal fixation are likely to occur.Bone mass density plays an important role in the strength and stability of endophytic fixation.Regional differences in the bone mass density of the distal clavicle should not be overlooked in the repair and reconstruction of acromioclavicular dislocation.Currently,there are no quantitative clinical studies in humans regarding the bone mass density of the distal clavicle. OBJECTIVE:To measure the magnitude of bone mass density in different regions of the distal clavicle by quantitative CT to provide a reference for surgeons to repair and reconstruct the coracoclavicular ligament. METHODS:101 patients undergoing quantitative CT checking in Fuyang People's Hospital Affiliated to Anhui Medical University from October to December 2022 were enrolled,from which 1 616 samples of subdivisional bone mass density of the distal clavicle were measured.For each of the quantitative CT samples,firstly,the distal clavicle was divided medially to laterally into the following four regions:conical nodal region(region A),inter-nodal region(region B),oblique crest region(region C)and distal clavicular region(region D).Secondly,each region was divided into the first half and the second half to determine eight subdivisions,then setting semiautomatic region of interest(ROI)in each subdivision:(ROI A1,A2,B1,B2,C1,C2,D1,and D2).Thirdly,each quantitative CT scan was transferred to the quantitative CT pro analysis workstation,and cancellous bone mass density was measured in the distal clavicle ROI.Finally,the clavicular cortex was avoided when measuring. RESULTS AND CONCLUSION:(1)There was no statistically significant difference in bone mineral density on the different sides of the shoulder(P＞0.05).(2)The analysis of bone mineral density in eight sub-areas of the distal clavicle A1,A2,B1,B2,C1,C2,D1,and D2 showed statistically significant differences(P＜0.05).It could be considered that there were differences in bone mineral density in different areas of the distal clavicle.After pairwise comparison,there was no statistically significant difference in bone mineral density between A1 and A2,D1 and D2,A2 and B1(P＞0.05),and there was a statistically significant difference in bone mineral density between the other sub-areas(P＜0.05).(3)The bone mineral density in the region A2 of the anatomical insertion of the conical ligament was significantly higher than that in the inter-nodular area(region B)(P＜0.05).The bone mineral density in the region A1 was higher than that in the region A2,but the difference was not statistically significant(P＞0.05).The bone mineral density in the region C1 of the anatomical insertion of the trapezium ligament was higher than that in regions C2,D1 and D2,and the bone mineral density in the inter-nodular area(region B)was significantly higher than that in regions C and D(P＜0.05).(4)These results have suggested that there are differences in bone mass density in different regions of the distal clavicle;regional differences in bone mass density in the distal clavicle during repair and reconstruction of acromioclavicular dislocation cannot be ignored.Consideration should be given not only to biomechanical factors but also to the placement of implants or bone tunnels in regions of higher bone mass density,which could improve the strength and stability of implant fixation and reduce the risk of complications such as bone tunnel enlargement,osteolysis,fracture and implant failure.