The purpose of this review is to provide an overview of the effect of (lymph)angiogenic cytokines on hematopoietic cells involved in acute myeloid leukemia (AML). Like angiogenesis, lymphangiogenesis occurs in pathophysiological conditions but not in healthy adults. AML is closely associated with the vasculature system, and the interplay between lymphangiogenic cytokines maintains leukemic blast survival in the bone marrow (BM). Once AML is induced, proangiogenic cytokines function as angiogenic or lymphangiogenic factors and affect hematopoietic cells, including BM-derived immune cells. Simultaneously, the representative cytokines, VEGFs and their receptors are expressed on AML blasts in vascular and osteoblast niches in both the BM and the peripheral circulation. After exposure to (lymph)angiogenic cytokines in leukemogenesis and infiltration, immune cell phenotypes and functions are affected. These dynamic behaviors in the BM reflect the clinical features of AML. In this review, we note the importance of lymphangiogenic factors and their receptors in hematopoietic cells in AML. Understanding the functional characterization of (lymph)angiogenic factors in the BM niche in AML will also be helpful in interrupting the engraftment of leukemic stem cells and for enhancing immune cell function by modulating the tumor microenvironment.
Animals ; Cytokines/*immunology ; Hematopoietic Stem Cells/immunology/*pathology ; Humans ; Immunity, Cellular ; Leukemia, Myeloid, Acute/immunology/*physiopathology ; *Lymphangiogenesis ; Lymphatic Vessels/immunology/*physiopathology ; Vascular Endothelial Growth Factor A/immunology

OBJECTIVETo evaluate the effects of endothelial cell- targeted soluble Notch ligand hD1R protein on expansion and engraftment of cord blood hematopoietic stem/progenitor cell (CB HSPCs).

METHODSRecombinant hD1R protein was first induced and purified. Human cord blood CD34⁺ cells were co-cultured on human umbilical vein endothelial cells (HUVECs) supplemented with a cocktail containing 5 types of human cytokines including TPO, SCF, FL, IL-6, IL-3 (5GF) and soluble hD1R. The expansion of CD34⁺ cells was tested under different culture conditions including PBS group (PBS replaces HUVEC), hD1R group, sup group (HUVEC supernatant replaces HUVEC), fix group (fixed HUVEC replaces HUVEC), Day 0 group (Control). Cell cycle and apoptosis of cultured cells were also analyzed. Their progeny expanded in PBS or hD1R group were transplanted into sublethally irradiated NOD/SCID mice. The percentages of human CD45⁺ (hCD45⁺) cells in the marrow of recipient mice were determined by FACS 12 weeks later.

RESULTShD1R induced more expansion in the total number of CD34⁺ cells cocultured with HUVECs plus 5GF, which was 87.50-fold increase compared to the Day 0 group, and 7.98-fold increase than that of PBS group. FACS analysis also showed that the percentage of CD34⁺ cells was 77.0% in G0/G1 phase in the hD1R group, which indicated that hD1R enhanced HSPCs expansion and inhibited apoptosis. Moreover, hD1R significantly promoted human HSPC engraftment after BM transplantation in irradiated mice.

CONCLUSIONThe Notch-mediated ex vivo expansion system has been established and hD1R promoted expansion and engraftment of human CB HSPCs, which provided the evidence for further clinical application.

Animals ; Antigens, CD34 ; Cells, Cultured ; Coculture Techniques ; Endothelial Cells ; immunology ; Fetal Blood ; Hematopoietic Stem Cells ; immunology ; Humans ; Membrane Proteins ; immunology ; Mice

The understanding of main mechanisms that determine the ability of immune privilege related to Sertoli cells (SCs) will provide clues for promoting a local tolerogenic environment. In this study, we evaluated the property of humoral and cellular immune response modulation provided by porcine SCs. Porcine SCs were resistant to human antibody and complement-mediated formation of the membrane attack complex (38.41+/-2.77% vs. 55.02+/-5.44%, p=0.027) and cell lysis (42.95+/-1.75% vs. 87.99 +/-2.25%, p<0.001) compared to immortalized aortic endothelial cells, suggesting that porcine SCs are able to escape cellular lysis associated with complement activation by producing one or more immunoprotective factors that may be capable of inhibiting membrane attack complex formation. On the other hand, porcine SCs and their culture supernatant suppressed the up-regulation of CD40 expression (p<0.05) on DCs in the presence of LPS stimulation. These novel findings, as we know, suggest that immune modulatory effects of porcine SCs in the presence of other antigen can be obtained from the first step of antigen presentation. These might open optimistic perspectives for the use of porcine SCs in tolerance induction eliminating the need for chronic immunosuppressive drugs.
Animals ; Antibodies, Heterophile/immunology ; Antibody Formation/*immunology ; Antigens, CD40/immunology ; Aorta/cytology ; Cell Line, Transformed ; Cell Survival/immunology ; Complement Membrane Attack Complex/immunology ; Complement System Proteins/immunology ; Dendritic Cells/cytology/immunology ; Endothelial Cells/cytology/immunology ; Epitopes/immunology ; Humans ; Immune Tolerance/*immunology ; Immunity, Cellular/*immunology ; Male ; Mice ; Mice, Inbred C57BL ; Sertoli Cells/cytology/*immunology ; Swine ; *Tissue Engineering ; Transplantation, Heterologous

OBJECTIVETo investigate the prevalence of anti-endothelial cell antibodies (AECAs) in the sera of connective tissue diseases (CTD) patients with pulmonary arterial hypertension (PAH) and its correlation with clinical manifestations.

METHODSAECAs in sera of 39 CTD patients with PAH, 22 CTD patients without PAH, and 10 healthy donors as controls were detected with Western blotting. The prevalence of different AECAs in different groups was compared and its correlation with clinical manifestations was also investigated.

RESULTSThe prevalence of AECAs was 82.1% in CTD patients with PAH, 72.7% in CTD patients without PAH, and 20.0% in healthy donors. Anti-22 kD AECA was only detected in CTD patients with PAH (15.4%). Anti-75 kD AECA was more frequently detected in CTD patients with PAH than in those without PAH (51.3% vs. 22.7%, P < 0.05). In CTD patients with PAH, anti-75 kD AECA was more frequently detected in those with Raynaud's phenomenon or with positive anti-RNP antibody.

CONCLUSIONAECAs could be frequently detected in CTD patients with or without PAH, while anti-22 kD and anti-75 kD AECA might be specific in CTD patients with PAH.

Adult ; Autoantibodies ; blood ; immunology ; Cell Line ; Connective Tissue Diseases ; blood ; immunology ; pathology ; physiopathology ; Endothelial Cells ; cytology ; immunology ; Female ; Humans ; Hypertension, Pulmonary ; blood ; immunology ; pathology ; physiopathology ; Middle Aged

OBJECTIVETo study the relationship between simian acquired immunodeficiency syndromn (SAIDS) and autoimmunity in simian immunodeficiency virus (SIV)-infected monkeys.

METHODSIndirect immunofluorescence assays were performed to detect plasma or serum autoantibodies in SIV-infected monkeys. The heart, liver, spleen, lung, kidney, and lymph node of BALB/c mice, a strain of endothelial cell ECV304, and granulocytes were used as target antigens. These results were compared with HE stained slides of SIV-infected monkeys.

RESULTSThe levels of various autoantibodies, including anti-lymphocyte autoantibodies, anti-endothelial cell autoantibodies, and anti-granulocyte antibodies, increased after SIV infection in monkeys. Moreover, pathological examinations showed injuries in the lymphoid tissue and vascular pathological changes in cerebral cortex, submucosa of gastrointestinal tract, interstitial capillaries of myocardium, nephron of the kidney, and sinusoid cell of liver.

CONCLUSIONThe increased autoantibodies and the pathological changes of tissues and organs confirm the existence of autoimmunity in SIV-infected monkeys.

Animals ; Autoantibodies ; blood ; Autoimmunity ; Endothelial Cells ; immunology ; Granulocytes ; immunology ; Lymphocytes ; immunology ; Mice ; Mice, Inbred BALB C ; Simian Acquired Immunodeficiency Syndrome ; immunology ; pathology ; Simian Immunodeficiency Virus

Tumor microenvironment is defined as a heterogeneous complex composed of cancer cells, vascular endothelial cells, fibroblasts, and diverse immune cells. Cancer immunology is the study of interactions between the immune system and cancer cells which is applied to develop therapeutic strategies for human cancers. This review focused on tumor promoting myeloid derived cells such as tumor associated macrophages (TAM) and myeloid derived suppressor cells (MDSC) and their therapeutic applications.
Allergy and Immunology ; Endothelial Cells ; Fibroblasts ; Humans ; Immune System ; Macrophages ; Tumor Microenvironment

OBJECTIVETo investigate whether fetal bone marrow stromal cells have hemangioblastic characteristics.

METHODSHuman fetal bone marrow stromal cells (hfMSCs) were isolated and cultured. Immunophenotypes of hfMSCs were tested by FACS. hfMSCs seeded in the matrigel were induced with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in vitro. Vascularization and hematopoiesis were detected with immunohistochemistry and electron microscope.

RESULTSThe typical properties of this CD34- stromal cell population were that 99% cells expressed Flk1 (vascular endothelial cell growth factor receptor 2) and tube structure was formed. In the process of induction, hfMSCs could give rise to CD34+ round cells.

CONCLUSIONSWe have demonstrated that fetal bone marrow stroma-derived Flk1+ CD34- cells could differentiate into vascular endothelial cells and hematopoietic cells, indicating that fetal bone marrow stroma-derived Flk1+ CD34- cells have hemangioblastic characteristics.

Antigens, CD34 ; immunology ; Bone Marrow Cells ; cytology ; immunology ; metabolism ; Cell Differentiation ; Cells, Cultured ; Fetus ; Fibroblast Growth Factor 2 ; metabolism ; Hematopoiesis ; Hematopoietic Stem Cells ; cytology ; immunology ; metabolism ; Humans ; Immunophenotyping ; Stromal Cells ; cytology ; immunology ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; physiology

This study was purposed to investigate the immunoregulatory effect of endothelial cells derived from mesenchymal stem cells (MSC). The human MSC was induced to differentiate into endothelial cells for one week. The phenotypes were evaluated by flow cytometry, the cell morphologic feature was observed by invert phase-contrast microscope and analysis of capillary formation was performed by using the in vitro angiogenesis kit. The immunoregulatory effect was detected by lymphocyte transformation test. The result indicated that during the differentiation cells grew fast and there was no significant change in the phenotypes, i.e. CD73, CD105, HLA-ABC were positive and CD34, CD80, CD86, HLA-DR, CD31 were negative. Immunofluorescence analysis showed typical expression of the von Willebrand factor. Differentiated MSCs formed capillary-like structure. Endothelial cells derived from MSC also revealed immunosuppressive effect on T cell proliferation in a dose-dependent manner. It is concluded that endothelial cells derived from MSC also harbor immunoregulatory effect on T lymphocytes.
5'-Nucleotidase ; metabolism ; Cell Differentiation ; physiology ; Cells, Cultured ; Child ; Endothelial Cells ; cytology ; immunology ; Humans ; Mesenchymal Stromal Cells ; cytology ; metabolism ; T-Lymphocytes ; immunology ; von Willebrand Factor ; metabolism

OBJECTIVETo prepare the polyclonal antibody of human endothelial-overexpressed lipopolysaccharide-associated factor 1 (EOLA1), and to determine the expression of EOLA1 in human umbilical vein endothelial cell (HUVEC).

METHODSThe protein samples (sample 1 and 2) expressing EOLA1 were purified and renatured. The protein concentrations were determined with bicinchoninic acid assay. The protein samples were identified with peptide mass fingerprinting (PMF) analysis. Protein sample with higher coincidence rate of amino acid sequence with theoretic protein was used to inoculate 4 mice; another 4 mice inoculated with adjuvant were used as control. Serum was isolated from collected mice blood. Polyclonal antibody of EOLA1 was purified with saturated ammonium sulfate precipitation, and was determined with ELISA for the titer (data were denoted by absorbance value). The expression of EOLA1 in HUVEC was determined with Western blot.

RESULTSThe concentration of protein sample 1 and 2 was respectively 0.124 16 mg/mL and 0.132 15 mg/mL. According to PMF analysis, the coincidence rate of amino acid sequence between protein samples and theoretic protein were 32% (protein sample 1) and 24% (protein sample 2). The polyclonal antibody of EOLA1 with titer more than 1:10 000 was obtained from mice inoculated with protein sample 1. The expression of EOLA1 protein in HUVEC was determined with polyclonal antibody of EOLA1.

CONCLUSIONSThe polyclonal antibody of EOLA1 can be prepared by inoculating mice with EOLA1 prokaryotic expressing protein, which can be used for determination of EOLA1 protein.

Animals ; Antibodies ; Cells, Cultured ; Human Umbilical Vein Endothelial Cells ; metabolism ; Humans ; Lipopolysaccharides ; metabolism ; Membrane Proteins ; immunology ; metabolism ; Mice

In order to study the possible mechanism of CD226 monoclonal antibody (mAb)-mediated intracellular message transduction in human umbilical vein endothelial cells (HUVECs), the influence of CD226 mAb and its cross-linking by secondary antibody (II Ab) on the concentration changes in [Ca(2+)](i) in the HUVECs under different conditions were determined by confocal laser scanning microscopy. The main results are as follows. (1) When the culture medium was balanced by Hanks Buffer, [Ca(2+)](i) in HUVECs increased slowly after stimulation by CD226 mAb, whereas [Ca(2+)](i) increase was accompanied by [Ca(2+)](o) decrease after the mAb was cross-linked by goat anti-mouse IgG. Then [Ca(2+)](i) and [Ca(2+)](o) all returned to the normal level. (2) When the culture medium was balanced by D-Hanks buffer, [Ca(2+)](i) in HUVECs showed little variation when the cells were stimulated by CD226 mAb, but [Ca(2+)](i) decreased markedly after cross-linking. (3) When HUVECs were pretreated with EGTA, there was no variation in [Ca(2+)](i) of HUVECs after CD226 mAb stimulation alone or cross-linking of the mAb. Our results suggest that stimulation by CD226 mAb and cross-linking by goat anti-mouse IgG induce the variation of [Ca(2+)](i) in HUVECs under different conditions and the variation of [Ca(2+)](i) in HUVECs may play an important role in many physiological and pathological processes.
Antibodies, Monoclonal ; pharmacology ; Antigens, Differentiation, T-Lymphocyte ; immunology ; Calcium ; metabolism ; Cells, Cultured ; Human Umbilical Vein Endothelial Cells ; metabolism ; physiology ; Humans