Objective To study the effect of transforming growth factor β1(TGF-β1) and insulin-like growth factor 1(IGF-1) during the induction course from marrow mesenchymal stem cells (MSCs) to chondrocytes and to observe the effect of cell density on cell induction. Methods Differential time adherent methods were used to purify MSCs obtained from the bone marrow of Kunming mice. MSCs were cultured under special conditionsto induce themto differentiate into chondrocytes. Toluidine blue staining and immunofluoresence were used to identify those induced chondrocytes.TGF-β1 and IGF-1 were used individually or in combination under two different culture patterns: pellet culture and monolayer culture. According to different growth factors, experiment included 3 experimental groups(TGF-β1+IGF-1 group,10 ng/mland 50 ng/ml respectively;TGF-β1 group, 10 ng/ml; and IGF-1 group, 50 ng/ml) and control group(without growth factor). In TGF-β1+IGF-1 group, toluidine blue staining and immunofluoresence staining were carried out at 14 days and 21 days. The effect ofTGF-β1 and IGF-1 on the expression of collagen Ⅱgene was detected by RT-PCR at 7, 14 and 21 days of induction; the expressionsof collagen Ⅱ were compared between two culture patterns. Results In TGF-β1+IGF-1 group, the histological examination and immunofluoresence showed that those inducted chondyocytes could express collagen Ⅱ at 14 days. The gel electrophoresis results showed that the fragment of collagen Ⅱ gene was seen in TGF-β1+IGF-1 group andTGF-β1 group and that no fragment ofcollagen Ⅱ gene was seen in IGF-1 group and control group. The expression of collagen Ⅱ gene was ber in TGF-β1+ IGF-1 group than inTGF-β1 group, showing significant difference(Plt;0.05). Cells expressed more collagen Ⅱ under pellet culture than under monolayer culture. Conclusion IGF-1 could enhance the effect ofTGF-β1 during the induction course from MSCs to chondrocytes. A certain extent of high cell density is more effective for MSCs to differentiate into chondrocytes.
Objective To explore the hemodynamic monitoring value of pulse-indicated continuous cardiac output( PiCCO) during lung transplantation. Methods Twenty patients with end-stage lung disease undergone lung transplantation were enrolled. Hemodynamic states were monitored by PiCCO and Swan-Ganz standard thermodilution pulmonary artery catheter( PAC) simultaneously at six stages throughout the study. Changes in the variables were calculated by subtracting the first fromthe second measurement( Δ1 ) and so on ( Δ1 to Δ5 ) . Results The linear correlation between intra-thoracic blood volume index( ITBVI) and stroke volume index( SVIpa) was significant ( r = 0. 654, P lt; 0. 05) , whereas pulmonary artery wedge pressure ( PAWP) poorly correlated with SVIpa( P gt; 0. 05) . Changes in ITBVI correlated with changes in SVIpa ( Δ1 , r =0. 621; Δ2 , r = 0. 784; Δ3 , r = 0. 713; Δ4 , r = 0. 740; Δ5 , r = 0. 747; all P lt; 0. 05) , whereas PAWP failed. The mean bias between CIart and CIpa was ( 0. 09 ±0. 5) L·min-1 ·m-2 ; the limit of agreement was ( - 0. 89 ～1. 07) L·min-1 ·m-2 . Conclusions There is good correlation between the two methods of PiCCO and PAC for reflecting the change of heart preload. PiCCO is reliable in hemodynamic monitoring in patients undergone lung transplantation.
Objective To investigate the causes and management strategies for lower limb ischemic necrosis following xenogeneic heterotopic heart transplantation from a multigene-edited pig to a rhesus monkey. Methods A xenogeneic heterotopic heart transplantation was performed on December 16, 2023, at the Institute of Experimental Animals of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, using a quintuple-gene-edited pig as the donor and a rhesus monkey as the recipient. On postoperative day (POD) 9, the recipient monkey underwent left lower limb amputation due to ischemic necrosis. Blood samples were collected at various time points after transplantation for analysis of hematologic parameters, liver and renal function, myocardial enzymes, and coagulation profiles. Ultrasound and computed tomography (CT) were used to evaluate anastomotic patency and cardiac structure. Immunological assays, including complement-dependent cytotoxicity (CDC) and IgG/IgM antibody detection, combined with clinical observations, were employed to assess rejection type and therapeutic response. Results The recipient monkey survived for 46 days after transplantation. Echocardiography demonstrated preserved biventricular systolic function in the recipient’s native heart, with left ventricular ejection fraction (LVEF) consistently exceeding 50%. In the donor pig heart, left ventricular endocardial thickening was noted on POD 9, followed by right ventricular endocardial thickening on POD 24, while LVEF remained around 35%. No hyperacute or acute rejection was detected immunologically. CDC positivity ranged between 3.4% and 5.1%, with IgG/IgM antibody binding trends consistent with CDC results. Following amputation, the recipient exhibited elevated inflammatory markers, coagulopathy, and reactive thrombocytosis, which later normalized. Immunohistochemical staining of the necrotic limb revealed arterial and venous thrombosis; however, no T-cell or B-cell infiltration was observed in vascular structures, thrombi, nerves, muscles, fascia, or skin tissues, with CD3 and CD20 staining both negative. Conclusion Limb ischemia after xenogeneic heart transplantation may be associated with lower extremity vascular thrombosis triggered by local trauma in the context of transplantation-induced inflammatory activation and coagulation dysfunction. While no clear lymphocyte-mediated rejection was observed, further studies are needed to explore the potential role of non-lymphocyte-mediated immune mechanisms.
