جستجوی مقالات مرتبط با کلیدواژه « فاگوسیتوز » در نشریات گروه « پزشکی »

Macrophages are one of the most important immune cells. Macrophages can be divided into two main subgroups of classical or inflammatory macrophages(M1) and alternative or non -inflammatory macrophages or (M2), due to different stimuli. One of the factors that causes the macrophage to orient towards M2, is the phagocytosis of apoptosis cells (efferocytosis). The phagocytosis of mesenchymal stem cells, can be very important in cell therapy due to immunomedulatory properties and their ability to modulate macrophage function. Mesenchymal stem cells were isolated from Wharton's jelly and characterized by flow cytometry as well as differentiation to Osteoblasts and adipocytes. MSCs in the passage 2 exposed to UV light for induction of apoptosis for thirty minutes and followed by incubation for two hours. The cells were then isolated and added to macrophages in a ratio of 4 to 1. After that cells were incubated for 48 hours, after incubation time the production of TNFα and IL10 cytokines was measured by ELISA and nitric oxide production was measured. Macrophages phagocytosis ability was also measured by yeast and apoptotic thymocytes phagocytosis in different groups. The phagocytosis of Wharton's jelly–Mesenchymal stem cells (WJ–MSCs) by macrophages reduces the production of inflammatory cytokine TNFα and increases the production of inhibitory cytokine IL-10. Nitric oxide production has decreased in these macrophages. Also, after phagocytosis of apoptotic WJ–MSCs, the ability of yeast phagocytosis in these macrophages was reduced and phagocytosis of apoptotic thymocyte was increased. The phagocytosis of apoptotic WJ–MSCs, induce non-inflammatory phenotype in macrophages. So, injected WJ–MSCs maintain their immunomodulatory properties even if they get apoptosed in the body.

Immune platelet resistance is a condition in which antibodies are produced against platelet antigens and cause damage to injected platelets by phagocytes and macrophages. The aim of this study is to evaluate the efficacy of flow cytometry in predicting the results of platelet injections and platelet resistance and selecting compatible platelet for patients.
This case-control study was performed on 15 patients with acute myeloid leukemia (AML) with two or multiple injections of platelets and 15 healthy subjects without a history of platelet injection. After marking the platelets with 5-Chloromethylfluorescein diacetate (CMFDA) and their adjacency to the serum of patients, the amount of phagocytosis of platelets by monocytes was assessed in the two groups.
FINDINGS: The mean phagocytic power of platelets by monocyte was 18.27 ± 2.86% in the control group, 68.47 ± 10.40% in the group of patients with immune platelet resistance, and 36.73 ± 15.21 in the group of patients without immune platelet resistance (p = 0.001). In addition, there was a significant negative correlation between phagocytic power of platelets by monocyte and Corrected Count Increment (CCI) at 1 and 24 hours (p = - 0.001).
Based on the results of this study and considering the high sensitivity of the flow cytometric method, the use of CMFDA is highly appropriate for evaluating platelet studies, and it can also be used for platelet crossmatch by flow cytometry.

Curcumin is a bright yellow chemical produced by some plants like Turmeric. The anti-inflammatory effects of Curcumin were recorded in some studies. This study was done to investigate the effects of the Curcumin on the physiological functions of rat blood monocytes.
This study was an experimental one. The study population consisted of 20 rats randomly categorized into the treatment and control groups. Curcumin was orally administered to treatment group in daily doses of 200 mg/kg from the beginning of the study and continued for 4 weeks. The control rats received PBS at the same volume. At the ends, the blood samples were taken from the rats and the monocytes were isolated under a ficoll-hypaque gradient. Isolated monocytes were challenged with opsonized yeast and the functions were evaluated.
The results showed that the monocytes isolated from the control and treatment groups have not shown any significant differences in phagocytosis after challenge with opsonized yeast (p=0.1). Nevertheless, the respiratory burst (P=0.009) and nitric oxide production (P=0.03) were decreased in curcumin treated rat compared to the control rats. Albeit, the biological activities of monocytes in the treatment group was increased compared to the monocytes isolated from the control group (P=0.0001).
Collectively, it seems that curcumin is a natural source to intervene the monocytes functions especially in autoimmune diseases so that monocytes hyperactivity causes immunopathological conditions.

Background and Cold storage results in clustering of gpIbα molecules on platelets. Consequently, the lectin domains of αMβ2 receptors on the liver macrophages recognize these molecules and ingest the platelets. Probably coverage of sugar molecules of gpIbα using galactose could prevent the recognition and ingestion of platelets by macrophages. The purpose of this study therby was to investigate this function. Twenty-one units of platelet concentrates (PCs) were prepared from Iranian Blood Transfusion Organization and each unit was divided into three portions. In glycosylation UDP-galactose was injected to one of the portions. The bags were kept in different temperatures (22°C or 4°C). The parameters of platelet counts, aggregation and the binding capacity of macrophages (THP1 cell line) to platelets and their ingestion were studied. Data was analyzed using the Wilcoxon test. The results showed that platelet counts and function remained almost stable in refrigerated platelets. Galactosylation and storage of PC in cold temperature led to a better response of platelets to agonists in the aggregation test but it could not prevent their subsequent ingestion and phagocytosis by THP1 monocytic cell line. Galactosylation and cold storage of platelets did not affect their phagocytosis by THP1cells. Because of the good maintenance of platelet count and function during storage of PC in cold, cold storage of PC could be an interesting area of research in future.

Mesenchymal stem cells (MSCs) are a population of adult stem cells which is an appropriate source for therapeutic purposes. The aim of this study was to investigate the effects of rat mesenchymal cells and soluble factors on the function of peripheral blood neutrophils. This experimental study was conducted on rat mesenchymal stem cells. Mesenchymal cells obtained from bone marrow of the femur and Tybaof 6-8 week rats and were cultured in DMEM. After maturation, the mesenchymal cells and supernatant at ratios of 1:4, 1:2 and 3:4 were adjacent with peripheral blood neutrophil phagocytosis. Subsequently, the respiratory burst of neutrophils, the yeast phagocytosis and nitroblue tetrazolium test was evaluated for revival. The Data were analyzed by t-tests, ANOVA and Tukey's test (p ˂0.05). The rates of phagocyted neutrophil treated with MSCs compared to controls were decreased.This reduction was not statistically significant (p ˂0.05).The phagocitic cell in the rats of the treated group with supernatant compared to the control group in all three ratios of 1:4, 1:2, 3:4 increased significantly (p ˂0.05. by the increase in the ratio was observed (05/0> p). Respiratory burst of neutrophils treated with mesenchymal stem cells compared to the control group significantly decreased. Respiratory burst was increased in the groups treated with cell supernatant at ratios of 1:2 only (P˂0.05). Mesenchymal cell-cell interaction with neutrophils was remarkable for therapeutic strategies in diseases associated with neutrophil function in response to physiological and pathological cell therapy with MSCs.

Introduction & Thalassemia is the most common genetic disorders in the world. These disorders are common in the Middle Estern countries containing Iran. It seems that factors like splenectomy, iron overload, frequent contacts with antigens during blood transfusion & using chelating agents cause severe disturbances to immune system. This study is done to evaluate the immune status in thalasemic patients refered to Ahvaz Shafa Hospital. This case- control study was done on 40 major thalassemic patients who had not the history of frequent bacterial and viral infections, splenectomy, using immunosuppressive drugs& patients with hepatitis, diabetes or other chronic diseases. Control group contained 31 healthy persons. Peripheral blood samples were collected from all participants. The last CBC and serum ferritin was taken from patient files. NBT test, evaluation of CD4, CD8, CD5, CD20 markers with flowcytometry, and assessment of IgG, IgM, and IgA levels with nephlometry method carried out on peripheral blood samples of patient and control groups. The percent of CD4, CD8 and CD5 markers and CD4/CD8 ratio had no significant difference between case & control groups. The percent of CD20 marker, and IgG, IgM & IgA levels were significantly higher in case group in comparison with control group. NBT test in all case and control groups were normal. There was no significant difference in serum ferritin, WBC count and percentage of lymphocytes and neutrophils among two groups. In major thalassemia patients, cellular immunity and phagocytosis are similar to normal individuals. CD4, CD8 and CD5 positive lymphocytes and CD4/CD8 ratio showed no difference between patients and normal groups. CD20 positive lymphocytes and IgM, IgG & IgA levels in patient group were significantly higher than normal control group. This can’t be due to viral or recurrent infections, because these patients were excluded from our study. This may related to increase in allo antibodies & auto antibodies due to frequent blood transfusion and antigen contact with in these patients which is not related to additional iron.

Chronic pulmonary infection in patients with cystic fibrosis is predominantly due to infection by mucoid strains of Pseudomonas aeruginosa. Mucoid P. aeruginosa is due to the production of exopolysaccharide called also alginate. Alginate in addition to interference with the clearance of lung has antiphagocytic property. Optimal killing activity of P. aeruginosa requires opsonic antibodies. Since immunomodulatory effects of garlic on enhancing phagocytic activity has been proved, in this study the effect of combination of alginate and an immunomodulator protein of garlic on production of opsonic antibodies against P. aeruginosa mucoid exopolysaccharide has been investigated. Alginate was extracted from a 72-hour culture of P. aeruginosa strain 8821M and then DNase1, RNaseA and Proteinase k were added. Subsequently, alginate was purified with gel filtration chromatography by sephacryl S-400. Female BALB/c mice aged 6-8 weeks were divided into five groups and injected subcutaneously on days 0,7,14 with either alginate, garlic, alginate- garlic, R10 or alginate-R10 and opsonophagocytic killing activity was calculated in each group. The purified alginate contained 34.6µg/ml uronic acid, 0.5 µg/ml nucleic acid, 1.45 µg/ml protein and 0.08µg/ml LPS. Opsonophagocytic killing activity after immunization with R10, alginate and their combination showed significant increases of respectively 69%, 67% and 82% comparing to the control group. Combination of P.aeruginosa alginate and immunomodulator fraction of garlic enhances immunogenicity to P.aeroginosa by the elicitation of opsonic antibodies in BALB/c mice.

Thalassemia is the most common blood disorder in the world. This hereditary anemia, Which develops due to a constitutional imbalance in alpha and beta chains of adult haemoglobin (hbA), has serious and life- threatening complications (accompanied by haemolysis and bone deformities) in its major form. We may encounter a diverse collection of articles in world research centers about the investigations carried out on Thalassemic patients. In the present research non- specific immune cells (neutrophiles) of these patients have been evaluated, additionally it is to be determined if there is any relationship between neutrophil function and such parameters as: serum ferritin level- splenectomy,desferal injection and the number of transfusions. We selected 30 patients with Beta-Thalassemia major, and 30 healthy persons as controls for neutrophiles from blood with Heparin anticoagulent (154/ml) with dextran 6% and used cold centrifugal for isolation of albicans candida from fungi collection upon SDA environment and in order to neutrophiles suspension, fungi from RPMI environment 1640 and PBS Bafer. The obtained data were analyzed by t-test or x-test. The result of this research shows that the neutrophils of thalassemia major patients are like the control group from the number and opsonisation, introducing N.B.T., however they have a weak function to the control group from Chemotaxi and Killing the organism. In this research should patients with Beta tgalassemia major in comparison with control group have allergy to infection.