Expert Consensus on the Application of Stem Cells in Psoriasis Research and Clinical Trials.

Psoriasis is an immune-mediated, chronic, relapsing, inflammatory, systemic disease induced by individual-environmental interactions, and is often lifelong because of the difficulty of treatment. In recent years, a variety of targeted therapies, including biologics, have improved the lesions and quality of life of most psoriasis patients, but they still do not address the problem of relapse and may be associated with decreased efficacy or adverse events such as infections over time. Therefore, there is an urgent need for breakthroughs in psoriasis treatment and in relapse-delaying and non-pharmacologic strategies, and stem cell therapy for psoriasis has emerged. In recent years, research on stem cell therapy for psoriasis has received a lot of attention, however, there is no reference standard as well as consensus in this field of research. Therefore, according to the latest consensus and guidelines, combined with relevant literature reports, clinical practice experience and the results of discussions with experts, this consensus specifies the types of stem cells commonly used in the treatment of psoriasis, the methods, dosages, and routes of stem cell therapy for psoriasis, as well as the clinical evaluations (efficacy and safety) of stem cell therapy for psoriasis. In addition, this consensus also provides normative standards for the processes of collection, preparation, preservation and quality control of stem cells and their related products, as well as recommendations for the management of stem cells during infusion for the treatment of psoriasis. This consensus provides the latest specific reference standards and practice guidelines for the field of stem cell therapy for psoriasis.

Lipopolysaccharide preconditioning increased the level of regulatory B cells in the spleen after acute ischaemia/reperfusion in mice.

BACKGROUND: The inflammatory reaction of the spleen is an important component in the pathophysiology of cerebral ischaemia (CI). Regulatory B cells (Bregs) derived from the spleen can inhibit the expansion of inflammation and reduce the damage caused by CI. AIM: The aim of the present study was to explore changes in spleen function and Bregs production due to lipopolysaccharide preconditioning (LPS PC) in ischaemia/reperfusion (I/R) and to uncover potential protective effect of LPS PC on stroke. METHODS: Focal cerebral I/R mice were induced by middle cerebral artery occlusion (MCAO). Infarct size and inflammatory cell infiltration in brain tissue, athletic ability, and immune status were analysed by immunostaining, behavioural analyses, and flow cytometry, respectively. RESULTS: The volume of the cerebral infarct was significantly decreased in I/R mice with LPS PC (LPS + I/R) compared to I/R mice, and neuronal apoptosis was ameliorated by LPS PC. After preconditioning with LPS, locomotor activity, forelimb strength, motor endurance, motor coordination, and short-term memory were improved to varying degrees. Moreover, blood-brain barrier (BBB) dysfunction was reversed, and CD11b+, major histocompatibility complex-II positive (MHC-II+), and Gr-1+ cell infiltration in the brains of LPS + I/R mice was also significantly reduced. B cell-activating factor (BAFF), tumour necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1ß), and IL-6 in the brain and spleen in the LPS + I/R group decreased to different degrees, while the levels of transforming growth factor-ß (TGF-ß) and IL-10 increased. LPS PC alleviated atrophy of the spleen following I/R. In addition, the number of CD8+ T cells, macrophages, TNF+ cells, NF-κB+ cells, and neutrophils in the spleen was reduced, while the number of proliferating cells and CD19+-IL10+ Bregs was significantly increased. The number of follicular B (FO B) cells and marginal zone B (MZ B) cells in the spleens of LPS + I/R mice was also increased. CONCLUSIONS: I/R mice preconditioned with LPS showed significantly reduced pathological damage, motor dysfunction, cognitive dysfunction, and inflammatory responses. LPS PC may initiate anti-inflammatory protective mechanism in the spleen after stroke, may increase the number of anti-inflammatory cells, such as Bregs, in the spleen, and may play a protective role in stroke.

[LFA-1 and VLA-4 involved in vasoendothelial adhesion and transendothelial migration of human high proliferative potential endothelial progenitor cells].

To investigate whether lymphocyte function-associated antigen 1 (LFA-1) and very late antigen 4 (VLA-4) are involved in vasoendothelial adhesion and transendothelial migration of high proliferative potential endothelial progenitor cells (HPP-EPCs), flow cytometry was used to analyze the expression of integrin beta1 and beta2, the expression of intercellular adhesion molecule (ICAM-1, 2) and vascular cell adhesion molecule (VCAM-1) in mouse bone marrow endothelial cells (mBMECs). The adhesion and transmigration through endothelial cells of the HPP-EPCs blocked by functional grade neutralizing antibodies of VLA-4 and LFA-1 were studied in vitro. The results revealed that HPP-EPCs were positive for CD11a and CD49d in HPP-EPCs. The expression of ICAM-1and VCAM-1 of mBMECs increased after activated by IL-1beta and TNF-alpha. The results of adhesion in vitro revealed that the numbers of the adhered and migrated cells in the CD11a antibody group, in the CD49d antibody group and in the combinational antibody group were less than those in the isotype control antibody group. Furthermore, the number of adhered and migrated cells in the combinational antibody group was less than that in the CD11a or the CD49d antibody group (p < 0.05). It is concluded that both LFA-1 and VLA-4 are involved in vasoendothelial adhesion and transendothelial migration of HPP-EPCs.

Inducing effects of macrophage stimulating protein on the expansion of early hematopoietic progenitor cells in liquid culture.

BACKGROUND: Macrophage stimulating protein (MSP) is produced by human bone marrow endothelial cells. In this study, we sought to observe its effects on inducing the expansion of early hematopoietic progenitor cells which were cultured in a liquid culture system in the presence of the combination of stem cell factor (SCF), interleukin 3 (IL-3), interleukin 6 (IL-6), granulocyte macrophage-colony stimulating factor (GM-CSF), erythropoietin (EPO) (Cys) and MSP or of Cys and bone marrow endothelial cell conditioned medium (EC-CM). METHODS: Human bone marrow CD34(+) cells were separated and cultured in a liquid culture system for 6 days. Granulocyte-macrophage colony forming unit (CFU-GM) and colony forming unit-granulocyte, erythrocyte, macrophage, megakaryocyte (CFU-GEMM) were employed to assay the effects of different treatment on the proliferation of hematopoeitic stem/progenitor cells. The nitroblue tetrazolium (NBT) reductive test and hoechest 33258 staining were employed to reflect the differentiation and apoptosis of the cells respectively. RESULTS: MSP inhibited the proliferation of CFU-GM and CFU-GEMM in semi-solid culture and the inhibitory effect on CFU-GEMM was stronger than on CFU-GM. MSP inhibited the differentiation of early hematopoietic progenitor cells induced by hematopoietic stimulators. Bone marrow (BM) CFU-GEMM was 2.3-fold or 1.7-fold increase or significantly decreased in either Cys + EC-CM, Cys + MSP or Cys compared with 0 hour control in liquid culture system after 6 days. CONCLUSION: MSP, a hematopoietic inhibitor, inhibits the differentiation of early hematopoietic progenitor cells induced by hematopoietic stimulators and makes the early hematopoietic progenitor cells expand in a liquid culture system.

[Effects of endothelial cells from cord blood on the amplification of human early hematopoietic cells from cord blood in vitro].

OBJECTIVE: To observe the effects of endothelial cells from umbilical cord blood (UCB) on the amplification of human early hematopoietic cells from UCB in vitro. METHODS: Endothelial cells from UCB were cultured by the optimized medium of endothelial cells. There were 2 experiment groups: cytokines group (SCF+IL-3+IL-6+GM-CSF, CKs group) and noncontact group (endothelial cell layer with CKs without contacting the CD34+ cells group). CD34+ cells from UCB were isolated by MiniMACS. After the cells in the CKs group and the noncontact group were cultured for 7 days, the amplifying folds of early hematopoietic cells were assayed. RESULTS: Early hematopoietic cells from UCB were expanded in the CKs group or the noncontact group. The amplifying folds of the noncontact group on early hematopoietic cells were significantly more than those of the CKs group. CONCLUSION: The amplification effect of the noncontact group on early hematopoietic cells is superior to that of the CKs group.

Angiogenic potential difference between two types of endothelial progenitor cells from human umbilical cord blood.

The hierarchy of endothelial progenitor cells (EPCs) in human umbilical cord blood has been disclosed. In this study we compare, for the first time, the angiogenic potential difference between two types of EPCs. We cultured mononuclear cells (MNCs) isolated from human umbilical cord blood using endothelial cell-conditioned medium and obtained two types of EPCs, referred to as circulating angiogenic cells (CACs) and high proliferative potential endothelial progenitor cells (HPP-EPCs). Both types of cells possess characteristics of EPCs, including expressing CD31, VE-cadherin, KDR and von Willebrand factor, uptake of Ac-LDL and binding to lectin. However, unlike CACs, which express CD14 but not CD133, HPP-EPCs express CD133 but not CD14. Also, unlike CACs, HPP-EPCs display stronger proliferation and clonogenic potential in vitro and show stronger ability to promote vascular growth in the hind-limb model of ischemia in mice (BALB/C-nu) in vivo.

[Promoting effects of serum-free murine bone marrow endothelial cell conditioned medium on the growth of bone marrow endothelial cells].

To study the effects of serum-free murine bone marrow endothelial cell conditioned medium (mBMEC-CM) on the growth of bone marrow endothelial cells, mBMEC-CM was collected and ultrafiltrated by Centriprep-10. The retentate of mBMEC-CM [molecular weight (MW)>10 kDa] and the filtrate of mBMEC-CM (MW<10 kDa) were obtained. The effect of bone marrow conditioned media, their components and exogenous cytokines on the formation of endothelial cell colonies were observed. The effect of bone marrow conditioned media, their components and exogenous cytokines on the proliferation of murine bone marrow endothelial cells were determined by [(3)H]-thymidine incorporation. The method of hybridizing to the Atlas cDNA array was used to determine the expression of cytokine mRNAs in bone marrow endothelial cells. The results obtained are as follows: vWF was expressed in bone marrow endothelial cells. The original mBMEC-CM and MW>10 kDa component of mBMEC-CM promoted the proliferation of bone marrow endothelial cell colonies and increased [(3)H]-thymidine incorporation of bone marrow endothelial cells. The MW<10 kDa component did not affect the production of endothelial cell colonies and did not increase [(3)H]-thymidine incorporation of endothelial cells. Six cytokines (IL-6, IL-11, SCF, GM-CSF, VEGF, bFGF) promoted the proliferation of bone marrow endothelial cell colonies. VEGF, bFGF and SCF increased [(3)H]-thymidine incorporation of bone marrow endothelial cells. According to the results of the Atlas cDNA array, GM-CSF,TGF-beta,BMP-2, bFGF, SCF, endothelin-2, thymosin beta10, MSP-1, connective tissue GF, PDGF-A chain, MIP-2 alpha, PlGF, neutrophil activating protein ENA-78, INF-gamma, IL-1, IL-6, IL-13, IL-11, inhibin-alpha mRNAs were expressed in endothelial cells. These results suggest that murine bone marrow endothelial cell conditioned medium promotes the proliferation of bone marrow endothelial cells.

[Effects of murine bone marrow endothelial cells on the in vitro expansion of human cord blood hematopoietic progenitor cells].

OBJECTIVE: To observe the effects of bone marrow endothelial cells on the expansion of human umbilical cord blood (UCB) hematopoietic progenitors in vitro. METHODS: Bone marrow endothelial cells were cultured and the serum free conditioned media (ECM) were collected. CD34+ cells derived from human umbilical cord blood (UCB) were isolated by MiniMACS. Hematopoietic progenitor cells were assayed after culturing with ECM or co-culturing with endothelial cell layer (ECL) for 24 hours. The effects of conditioned medium of endothelial cells which were cultured with bFGF (bFGF-ECM) on the expansion of cord blood hematopoietic progenitors also were investigated. RESULTS: UCB hematopoietic progenitors were significantly expanded by adding ECM or co-cultured with ECL, and ECM cultures and ECL cultures showed similar expansion effect on early progenitor cells. The effect of bFGF-ECM on the expansion of UCB hematopoietic progenitors was significantly better than that of ECM. CONCLUSION: Murine bone marrow endothelial cells support the quantitative expansion of UCB hematopoietic progenitor cells in vitro.

Expression of hematopoietic inhibitory factors in mouse fibroblasts, macrophages and endothelial cells.

Pure bone marrow fibroblasts, macrophages and endothelial cells were cultured in Iscove-modified Dulbecco's medium. RT-PCR was used to determine the expression of inhibitory cytokine mRNAs in these cell types. Serum-free conditioned medium was collected from each cell type and ultrafiltration was performed with a centriprep 10. The retentate contained substances whose molecular weights were >10 kD, whilst the filtrate contained substances with molecular weights <10 kD. The effect of conditioned media and their components on colony forming unit-granulocyte-macrophage (CFU-GM) were investigated. The results showed: (1) six cytokines, MIP-1alpha, MIP-2, TGF-beta, TNF-alpha, IFN-gamma and Tbeta(4), inhibited the growth of CFU-GM when murine WEHI-3 conditioned medium was added to the culture system as a source of colony stimulation. (2) The original endothelial cell conditioned medium (E-CM) did not affect the production of CFU-GM, but the >10 kD component of E-CM increased its production, and the <10 kD component decreased it. Both fibroblast conditioned medium (F-CM) and the >10 kD component of F-CM stimulated proliferation of CFU-GM, but the <10 kD component suppressed it. All three components of macrophage conditioned medium (M-CM) inhibited the growth of CFU-GM. (3) Expression of four of the mRNAs, namely MIP-2, TNF-alpha, INF-gamma and Tbeta(4), was seen in all three types of stromal cells, while TGF-beta mRNA was only seen in endothelial cells and macrophages, and MIP-1alpha mRNA in endothelial cells and fibroblasts. The inhibitors TGF-beta, MIP-1alpha, and Tbeta(4)have an inhibitory effect on the growth of CFU-GM, but TNF-alpha, INF-gamma and MIP-2 do not.

[Hematopoietic inhibitors elaborated by bone marrow endothelial cells].

UNLABELLED: In this study, the roles of hematopoietic inhibitors elaborated by bone marrow endothelial cells in the proliferation and differentiation of hematopoietic progenitors were investigated. Murine bone marrow endothelial cell conditioned medium (BMEC-CM) was collected and the components with > 10 kD and < 10 kD were obtained by centrifugal ultrafiltration. The effect of BMEC-CM and its components on proliferation of hematopoietic progenitors was evaluated by CFU-GM and HPP-CFC assay and antibody neutralization test. The expression of the inhibitors in BMEC and BMEC-CM was detected by RT-PCR and Western blot, and change of proliferation and differentiation-related genes during expansion of hematopoietic progenitors was examined by membrane hybridization technique. THE RESULTS: (1) When BME C-CM and its components directly were added to CFU-GM and HPP-CFC culture system, BMEC-CM had no effect on colony formation, > 10 kD component enhanced and < 10 kD component inhibited the formation of CFU-GM and HPP-CFC. (2) When BMEC-C M and its components were added to liquid culture system of marrow cells, after 24 hours incubation, CFU-GM decreased and HPP-CFC increased significantly in B MEC-CM group, CFU-GM increased and HPP-CFC had no significant change in > 10 kD component group; and both CFU-GM and HPP-CFC reduced in < 10 kD group. (3) MIP-2, MIP-1 alpha, MSP, TGF-beta, TNF-alpha, IFN-gamma and T beta 4 were expressed in murine marrow endothelial cells, and MIP-2, MIP-1 alpha, MSP, TGF-beta, TNF-alpha and T beta 4 were existed in BMEC-CM. (4) Antibody neutralization test results demonstrated that TGF-beta, MSP, MIP-1 alpha, IFN-gamma and T beta 4 existed in BMEC-CM had significant suppressive effects on CFU-GM and HPP-CFC. (5) T beta 4 combined with 5 hematopoietic cytokines (SCF, IL-3, IL-6, GM-CSF and EPO) added to CD34(+) cells expansion culture system, HPP-CFC significantly increased compared with 5 cytokines group. T beta 4 could downregulated the expression of proliferation and differentiation-related genes and signal transduction-related genes. It is concluded that BM EC-CM promotes the proliferation of early hematopoietic progenitor cells, and this effect is related with the inhibitors existed in BMEC-CM and it could be executed via influencing cell proliferation and differentiation-related genes and signal-related genes.