BACKGROUND AND OBJECTIVES: Mesenchymal stem cells (MSCs) are used to treat autoimmune or inflammatory diseases. Our aim was to determine the immunomodulatory mechanisms elicited by MSCs during inflammation. METHODS AND RESULTS: We cocultured MSCs with peripheral blood mononuclear cells for a mixed lymphocyte reaction or stimulated them by phytohemagglutinin. Morphological changes of MSCs and secretion of acetylcholine (ACh) from MSCs were measured. The effects of an ACh antagonist and ACh agonist on lymphocyte proliferation and proinflammatory-cytokine production were determined. The inflammatory milieu created by immune-cell activation caused MSCs to adopt a neuronlike phenotype and induced them to release ACh. Additionally, nicotinic acetylcholine receptors (nAChRs) were upregulated in activated peripheral blood mononuclear cells. We observed that ACh bound to nAChR on activated immune cells and led to the inhibition of lymphocyte proliferation and of proinflammatory-cytokine production. MSC-mediated immunosuppression through ACh activity was reversed by an ACh antagonist called α-bungarotoxin, and lymphocyte proliferation was inhibited by an ACh agonist, ACh chloride. CONCLUSIONS: Our findings point to a novel immunomodulatory mechanism in which ACh secreted by MSCs under inflammatory conditions might modulate immune cells. This study may provide a novel method for the treatment of autoimmune diseases by means of MSCs.
Acetylcholine ; Autoimmune Diseases ; Humans ; Immunosuppression ; Inflammation ; Lymphocyte Culture Test, Mixed ; Lymphocytes ; Mesenchymal Stromal Cells ; Methods ; Phenotype ; Receptors, Nicotinic

BACKGROUND: The relationship between hypertension and the lesion distribution of posterior reversible encephalopathy syndrome (PRES) is in debate. METHODS: Twenty patients with PRES which developed during chemotherapy or immunosuppression treatment for the control of underlying malignancy or auto-immune disorders were selected from the database. Data regarding brain images, clinical symptoms, co-morbid illnesses, and mean arterial pressure (MAP) at the pre-symptomatic period (one day before the symptom onset) and at the symptom onset were collected. Patients were divided into two groups according to the presence of pre-symptomatic hypertension. The lesion distribution degree was calculated by numerical method (involvement score [IS]) and compared with MAP. RESULTS: No significant differences of clinical symptoms were found between two groups. IS and onset period MAP were higher in the hypertensive group. Pre-symptomatic MAP correlated with onset period MAP and IS in total patients. No significant correlation was found between IS and onset period MAP. CONCLUSIONS: The PRES patient with hypertension in the pre-symptomatic period would show more spatially distributed brain lesions than the patient with stable blood pressure.
Arterial Pressure ; Blood Pressure ; Brain ; Drug Therapy ; Humans ; Hypertension ; Immunosuppression ; Methods ; Posterior Leukoencephalopathy Syndrome

Non-infectious uveitis is one of the leading causes of preventable blindness worldwide. Long-term immunosuppressive treatment is generally required to achieve durable control of inflammation in posterior and panuveitis. Although systemic corticosteroids have been the gold standard of immunosup- pressive treatment for uveitis since first introduced in 1950s, its side effects of long-term use often warrant an adjuvant treatment to reduce the dosage/duration of corticosteroids needed to maintain disease control. Conventional immunosuppressive drugs, classified into alkylating agent, antimetabolites and T cell inhibitors, have been widely used as corticosteroid-sparing agents, each with characteristic safety/tolerance profiles on different uveitis entities. Recently, biologic agents, which target specific molecules in immunopathogenesis of uveitis, have gained great interest as alternative treatments for refractory uveitis based on their favorable safety and effectiveness in a variety of uveitis entities. However, lack of large randomized controlled clinical trials, concerns about efficacy and safety of long-term usage, and economic burden are limiting the use of biologics in non-infectious uveitis. Local administration of immunosuppressive drugs (from corticosteroids to biologics) through intraocular drug delivery systems represent another direction for drug development and is now under intense investigation, but more evidences are needed to support their use as regular alternative treatments for uveitis. With the numerous choices belonging to different treatment modalities (conventional immunosuppressive agents, biologics and local drug delivery systems) on hand, the practice patterns have been reported to vary greatly from center to center. Factors influence uveitis specialists' choices of immunosuppressive agents may be complex and may include personal familiarity, treatment availability, safety/tolerability, effectiveness, patient compliance, cost concerns and suggestions from related specialists such as rheumatologists and pediatricians. The focus of this review is to provide an overview of each treatment modality on safety/tolerability and effectiveness, which are believed to be the two most important factors affecting treatment decision making.
Humans ; Immunosuppression ; methods ; Immunosuppressive Agents ; therapeutic use ; Uveitis ; immunology ; pathology ; therapy

BACKGROUNDRheumatic diseases involve multiple organs that are affected by immunological mechanisms. Treatment with corticosteroids and immunosuppressive agents may also increase the frequency of infection. Cytomegalovirus (CMV) is a widespread herpes virus and a well-recognized pathogen, which causes an opportunistic and potentially fatal infection in immunocompromised patients. This retrospective study aimed to investigate the clinical and laboratory characteristics of CMV pneumonia in patients with rheumatic diseases after immunosuppressive therapy in a single center in Shanghai, China.

METHODSEight hundred and thirty-four patients with rheumatic diseases who had undergone CMV-DNA viral load tests were included, and the medical records of 142 patients who were positive for CMV-DNA in plasma samples were evaluated. GraphPad Prism version 5.013 (San Diego, CA, USA) was used to conduct statistical analysis. The correlation between CMV-DNA viral loads and lymphocyte counts was assessed using the Spearman rank correlation coefficient test. Significance between qualitative data was analyzed using Pearson's Chi-squared test. The cut-off thresholds for CMV-DNA viral load and lymphocyte count were determined by receiver operating characteristic (ROC) curve analysis.

RESULTSOne hundred and forty-two patients had positive CMV viral load tests. Of these 142 patients, 73 patients with CMV pneumonia were regarded as symptomatic, and the other 69 were asymptomatic. The symptomatic group received higher doses of prednisolone (PSL) and more frequently immunosuppressants than the asymptomatic group (P < 0.01). The symptomatic group had lower lymphocyte counts, especially CD4+ T-cells, than the asymptomatic group (P < 0.01). By ROC curve analysis, when CD4+ T-cell count was <0.39 × 109/L, patients with rheumatic diseases were at high risk for symptomatic CMV infection. The CMV-DNA load was significantly higher in the symptomatic patients than that in asymptomatic patients (P < 0.01; threshold viral loads: 1.75 × 104 copies/ml). Seven patients had a fatal outcome, and they had lower peripheral lymphocyte counts (P < 0.01), including CD4+ and CD8+ T-cells (P < 0.01).

CONCLUSIONSWhen CD4+ T-cell count is <0.39 × 109/L, patients are at high risk for pulmonary CMV infection. Patients are prone to be symptomatic with CMV-DNA load >1.75 × 104 copies/ml. Lymphopenia (especially CD4+ T-cells), presence of symptoms, and other infections, especially fungal infection, are significant risk factors for poor outcome, and a higher PSL dosage combined with immunosuppressants may predict CMV pneumonia.

CD4-Positive T-Lymphocytes ; metabolism ; China ; Cytomegalovirus ; pathogenicity ; Cytomegalovirus Infections ; genetics ; immunology ; therapy ; virology ; Humans ; Immunosuppression ; methods ; Pneumonia ; genetics ; immunology ; therapy ; virology ; Polymerase Chain Reaction ; Retrospective Studies ; Rheumatic Diseases ; genetics ; immunology ; therapy ; virology ; Viral Load

OBJECTIVETo investigate the immunological characteristics of human tonsil mesenchymal stem cells (TMSCs).

METHODSHuman tonsil tissues were obtained from the children patients with chronic tonsillitis. TMSCs were separated, cultured, and were detected the expression profiles of HLA-I, HLA-II, CD80, CD86 by flow cytometry. The measurement of immunogenicity, the effect on phytohemagglutinin (PHA) induced peripheral blood mononuclear cell (PBMCs) proliferation and mixed lymphocytes reaction (MLR) were performed to identify the immunological characteristics of TMSCs. The co-cultures of TMSCs + PBMCs + PHA and TMSCs + MLR were established, respectively, and the concentration of kynurenine, which is the metabolin of indoleamine 2, 3-dioxygenase, in the culture supernatant were examined. Then we added 1-methyl-L-tryptophan into the co-culture of TMSCs + PBMCs + PHA and TMSCs + MLR, respectively, and tested the proliferation of PBMCs. Each experiment was repeated three times, and there were six samples in each group. Statistical significance was assessed by analysis of variance (ANOVA), and a P value less than 0.05 was considered statistically significant.

RESULTSTMSCs expressed HLA-I, were negative for HLA-II and co-stimulatory molecules CD80 and CD86. The stimulation index in the group of TMSCs + allogeneic PBMCs was 1.38 ± 0.26, whereas the stimulation index in the group of allogeneic PBMCs was 1.22 ± 0.28, and there was no significant difference between the two groups (P > 0.05), indicating that TMSCs could not initiate the proliferation of allogeneic PBMCs. The stimulation indexes in the group of TMSCs + allogeneic PBMCs + PHA were 1.49 ± 0.29 and 1.23 ± 0.22, respectively, whereas the stimulation index in the group of allogeneic PBMCs + PHA was 4.60 ± 0.81, and the difference between the two groups had a statistical significance (P < 0.05) suggesting that TMSCs could inhibit PHA-induced PBMCs proliferation. The stimulation indexes in the group of TMSCs + MLR were 1.29 ± 0.23 and 1.26 ± 0.27, respectively, however, the stimulation index in the group of MLR was 3.04 ± 0.66, and the difference between the two groups had a statistical significance (P < 0.05), demonstrating that TMSCs could suppress MLR-induced PBMCs proliferation. The levels of kynurenine were (26.0 ± 2.3) μmol/L and (23.5 ± 4.5) μmol/L in the culture of TMSCs + PBMCs + PHA and TMSCs + MLR, respectively, thus elevating significantly. After adding of 1-methyl-L-tryptophan, TMSCs-mediated-proliferation suppression of PBMCs restored to normal levels.

CONCLUSIONTMSCs possess low immunogenecity and immunosuppressive function, may be used in allogeneic transplantation.

Cell Proliferation ; Cells, Cultured ; Child ; Coculture Techniques ; Flow Cytometry ; Humans ; Immunosuppression ; Kynurenine ; analysis ; Leukocytes, Mononuclear ; Lymphocyte Culture Test, Mixed ; methods ; Mesenchymal Stromal Cells ; cytology ; immunology ; Palatine Tonsil ; cytology ; Tryptophan ; administration & dosage ; analogs & derivatives

Pancreatic islet transplantation is a physiologically advantageous and minimally invasive procedure for the treatment of type 1 diabetes mellitus. Here, we describe the first reported case of successful allogeneic islet transplantation alone, using single-donor, marginal-dose islets in a Korean patient. A 59-yr-old patient with type 1 diabetes mellitus, who suffered from recurrent severe hypoglycemia, received 4,163 islet equivalents/kg from a single brain-death donor. Isolated islets were infused intraportally without any complications. The immunosuppressive regimen was based on the Edmonton protocol, but the maintenance dosage was reduced because of mucositis and leukopenia. Although insulin independence was not achieved, the patient showed stabilized blood glucose concentration, reduced insulin dosage and reversal of hypoglycemic unawareness, even with marginal dose of islets and reduced immunosuppressant. Islet transplantation may successfully improve endogenous insulin production and glycemic stability in subjects with type 1 diabetes mellitus.
Blood Glucose/analysis ; Diabetes Mellitus, Type 1/*surgery ; Female ; Humans ; Hypoglycemia/*surgery ; Immunosuppression/methods ; Immunosuppressive Agents/therapeutic use ; Islets of Langerhans/physiology/*surgery ; Islets of Langerhans Transplantation/*methods ; Middle Aged ; Republic of Korea ; Tissue Donors

BACKGROUNDIn haploidentical hematopoietic stem cell transplantation (HSCT), the duration of graft-versus-host disease (GVHD) prophylaxis after modified donor lymphocyte infusion (DLI) was the only risk factor of DLI-associated grades 3-4 acute GVHD. However, the successful application of modified DLI depended not only on the reduction of severe GVHD, but also on the preservation of graft-versus-leukemia (GVL) effect. Therefore, this study was performed to compare the impact of prophylaxis for 6-8 weeks and prophylaxis for <6 weeks on GVL effect after modified DLI in haploidentical HSCT.

METHODSA total of 103 consecutive patients developing hematological relapse or minimal residual disease (MRD)-positive status after haploidentical HSCT and receiving modified DLI were investigated retrospectively. Fifty-two patients received prophylaxis for 6-8 weeks after modified DLI; the remaining 51 patients received prophylaxis for <6 weeks.

RESULTSFirst, compared with prophylaxis for <6 weeks, prophylaxis for 6-8 weeks reduced incidence of relapse in total patients (26.6% vs. 69.0%, P < 0.001). Besides, prophylaxis for 6-8 weeks also reduced incidence of relapse in 54 patients developing hematological relapse post-transplant (P = 0.018) and in 49 patients developing MRD-positive status post-transplant (P < 0.001). Second, prophylaxis for 6-8 weeks reduced incidence of acute GVHD (P < 0.05), reduced the therapeutic application of immunosuppressive agents (P = 0.019), but increased the incidence of chronic GVHD (P < 0.05). Third, prophylaxis for 6-8 weeks improved overall survival and disease-free survival in total patients, as well as in patients developing hematological relapse post-transplant and in patients developing MRD-positive status post-transplant (P < 0.05).

CONCLUSIONSIn haploidentical HSCT, prophylaxis for 6-8 weeks after modified DLI does not reduce GVL effect, but reduces the incidence of DLI-associated acute GVHD compared with prophylaxis for <6 weeks. This strategy will probably improve the safety and efficacy of modified DLI further.

Adolescent ; Adult ; Child ; Female ; Graft vs Host Disease ; prevention & control ; Hematopoietic Stem Cell Transplantation ; methods ; Humans ; Immunosuppression ; methods ; Leukemia ; therapy ; Male ; Middle Aged ; Neoplasm, Residual ; prevention & control ; Young Adult

No abstract available.
Animals ; Antigen-Presenting Cells/immunology ; Graft Rejection/immunology/*prevention & control ; Graft Survival ; *Histocompatibility ; Humans ; Immunosuppression/*methods ; Intercellular Adhesion Molecule-1/immunology ; Isoantigens/*immunology ; Organ Transplantation/*adverse effects ; *Transplantation Tolerance

Heart transplantation is now regarded as the treatment of choice for end-stage heart failure. To improve long-term results of the heart transplantation, we analyzed causes of death relative to time after transplantation. A total of 201 consecutive patients, 154 (76.6%) males, aged > or = 17 yr underwent heart transplantation between November 1992 and December 2008. Mean ages of recipients and donors were 42.8 +/- 12.4 and 29.8 +/- 9.6 yr, respectively. The bicaval anastomosis technique was used since 1999. Mean follow up duration was 6.5 +/- 4.4 yr. Two patients (1%) died in-hospital due to sepsis caused by infection. Late death occurred in 39 patients (19.4%) with the most common cause being sepsis due to infection. The 1-, 5-, and 10-yr survival rates in these patients were 95.5% +/- 1.5%, 86.9% +/- 2.6%, and 73.5% +/- 4.1%, respectively. The surgical results of heart transplantation in adults were excellent, with late mortality due primarily to infection, malignancy, and rejection. Cardiac deaths related to cardiac allograft vasculopathy were very rare.
Adult ; Anastomosis, Surgical/methods ; Female ; Follow-Up Studies ; Graft Rejection/mortality ; Heart Transplantation/*mortality ; Humans ; Immunosuppression/methods ; Infection/mortality ; Male ; Middle Aged ; Neoplasms/mortality ; Postoperative Complications/mortality/surgery ; Survival Rate ; Transplantation/*mortality ; Treatment Outcome

Heart transplantation is a standard treatment for end-stage heart disease. Pediatric heart transplantation, however, is not frequently performed due to the shortage of pediatric heart donors. This is the first report of pediatric heart transplantation in Korea. Our retrospective study included 37 patients younger than 18 yr of age who underwent heart transplantation at Asan Medical Center between August 1997 and April 2009. Preoperative diagnosis was either cardiomyopathy (n = 29, 78.3%) or congenital heart disease (n = 8, 22.7%). Mean follow up period was 56.9 +/- 44.6 months. There were no early death, but 7 late deaths (7/37, 18.9%) due to rejection after 11, 15, 41 months (n = 3), infection after 5, 8, 10 months (n = 3), suspicious ventricular arrhythmia after 50 months (n = 1). There was no significant risk factor for survival. There were 25 rejections (25/37, 67.6%); less than grade II occurred in 17 patients (17/25, 68%) and more than grade II occurred in 8 patients (8/25, 32%). Actuarial 1, 5, and 10 yr survival was 88.6%, 76.8%, and 76.8%. Our midterm survival of pediatric heart transplantation showed excellent results. We hope this result could be an encouraging message to do more pediatric heart transplantation in Korean society.
Adolescent ; Arrhythmias, Cardiac/mortality ; Cardiomyopathies/surgery ; Child ; Child, Preschool ; Female ; Graft Rejection/mortality ; Heart Defects, Congenital/surgery ; *Heart Transplantation ; Humans ; Immunosuppression/methods ; Infant ; Infection/mortality ; Male ; Postoperative Complications ; Republic of Korea ; Retrospective Studies ; Tissue Donors ; Treatment Outcome