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PubMed1992

T lymphocyte subsets and NK cell cytotoxicity in chronic hemodialysis patients. The effect of recombinant human erythropoietin (rHu-EPO) treatment.

We investigated subpopulations of T lymphocytes, NK cell number and cytotoxic activity in 14 chronic uremic patients on regular hemodialysis treatment. We observed a significantly decreased absolute lymphocyte number and percentage of CD3 cells. Relative numbers of CD16 cells were significantly elevated, but NK cell cytotoxic activity was within a normal range. Nine patients with chronic renal anemia on maintenance hemodialysis were enrolled in rHu-EPO treatment trial. The treatment was continued till the hematocrit level reached 30%. Each of the patients had corrected anemia and well-being. After 12 weeks of the treatment we observed in these patients decreases in CD3, CD4, CD8 and CD16 cell numbers and elevation of CD4/CD8 ratio. Cytotoxic activity of NK cells did not change significantly. Presented results indicate that chronic hemodialysis patients have significantly diminished lymphocyte number. rHu EPO treatment affects the T lymphocyte subsets inducing a deep decrease of CD8 and CD16 cell percentage leading to normalisation of the CD4/CD8 ratio.

Adolescent↗
PubMed2003

Dysregulation of blood lymphocyte subsets and natural killer cells in schistosomal liver cirrhosis and hepatocellular carcinoma.

Immunological factors are important in the pathogenesis of a wide spectrum of hepatobiliary diseases. Using flow cytometry, we determined the changes in lymphocyte subsets and natural killer cells in 123 individuals (81 patients with liver disease and 42 healthy volunteers). The liver diseases included periportal fibrosis (PPF, 10 patients), liver cirrhosis (LC, 31 patients), and hepatocellular carcinoma (HCC, 40 patients). Schistosomiasis and viral hepatitis B and C were the putative etiological agents of liver diseases. Immunophenotyping by indirect immunofluorescence was conducted using monoclonal antibodies to CD3 (T-lymphocytes), CD4 (helper/inducer T-cells), CD8 (suppressor/cytotoxic T-cells), and CD57 (natural killer cells) cell surface markers. Immunophenotyping of PPF patients showed no significant changes in all markers compared with the healthy controls. However, there was a significant decrease ( P<0.01) in CD3 and CD4 T-cells, and a highly significant increase ( P<0.001) in CD57 T-cells in patients with LC or HCC. In addition, LC and HCC patients showed no significant change in CD8 T-cells compared with controls. In conclusion, the progression of liver diseases is associated with a dysregulation of cellular immune responses. T-lymphocytes and natural killer cells may play a role in the immunopathogenesis of liver cirrhosis and HCC.

CD4-CD8 Ratio↗
PubMed1987

Alterations in lymphocyte subsets and serum immunoglobulin levels in patients with silicosis.

The numbers of total lymphocyte and lymphocyte subsets in peripheral blood of patients with silicosis and their serum immunoglobulin (Ig) levels were studied to evaluate their immune status. The numbers of total lymphocytes and OKT4+ and OKT8+ cells tended to be decreased and the numbers of OKT3+ cells was significantly decreased (p less than 0.001), but that of OKIa-1+ cells was increased (p less than 0.001) in the patients. In the lymph nodes of the lung hilus, the ratio of OKT4+ cells to total lymphocytes was increased but that of OKT8+ cells to total lymphocytes was decreased. The serum levels of IgG and IgA were elevated in the patients with reduction in the numbers of total lymphocytes and OKT4+ cells in peripheral blood. The serum IgE levels in 17 of 82 patients were above 400 IU/ml. In 8 patients with serum IgE 82 patients were above 400 IU/ml. In 8 patients with serum IgE levels of more than 1,000 IU/ml, the numbers of total lymphocytes and OKT3+ and OKT4+ cells were decreased compared with those in controls. The following suggestions are proposed from the results: Increase and activation of helper T cells may be caused by the presentation of silica dust to macrophages in the lymph nodes, and these cells may then stimulate B cell proliferation and Ig production by B cells, resulting in increase in the serum Ig (IgG, IgA and IgE) level. Reduction in the number of OKT4+ cells helper/inducer T cells) in peripheral blood may be due to migration of helper T cells into the lymph nodes. These immunological events in patients with silicosis are probably due to the adjuvant effect of silica dust.

Adult↗
PubMed1998

T-and B-lymphocyte subsets in patients with Dupuytren's disease. Correlations with disease severity.

Previous reports have indicated that inflammatory mechanisms may be involved in the pathogenesis of Dupuytren's disease and it has even been suggested that this condition is a T-cell mediated autoimmune disorder. We investigated peripheral blood lymphocyte subsets from 21 patients with Dupuytren's disease and compared them with ten healthy blood donors. The Dupuytren's patients had an increase in DR+ T-cells compared with healthy controls. Furthermore, patients with both palmar and plantar involvement had a higher percentage of DR+ T-cells than those with only the palm affected. The percentage of circulating CD5+ B-cells was lower in the Dupuytren's patients compared with the control group; this feature was marginally significant for the whole group of Dupuytren's patients but was strongest in the group of patients with both palmar and plantar involvement. These findings support previous suggestions that immunological mechanisms, involving activated T-cells and probably also B-cells, are involved in the pathogenesis of Dupuytren's disease.

Adult↗
PubMed1986

Abnormalities of lymphocyte subsets and anti-LAV/HTLV-III status in Greek hemophiliacs.

Peripheral blood lymphocyte subsets and the incidence of LAV/HTLV-III antibodies were studied in 63 patients with hemophilia A who had been transfused with a low dose regimen of commercial (U.S.A.) factor VIII concentrates. Five patients with hemophilia B were also included in this study. In hemophilia A patients a significant reduction in the percentage and absolute numbers of T4+ cells and of the T4/T8 ratio and a significant increase in the percentage of T8+ and Leu-7+ cells were observed. These abnormalities were independent of the presence of anti-LAV/HTLV-III. In hemophilia B patients a significant increase of T8+ cells and a decrease of T4/T8 ratio was noted while the percentage of Leu-7+ cells was normal. A significant negative correlation of F VIII units transfused and T4/T8 ratio was seen only in LAV/HTLV (-) patients, suggesting that F VIII per se could cause immunodysregulation. Seropositive patients were found to have consumed a larger amount of F VIII units than seronegative patients during the period 1980-1984 (p less than 0.005).

Acquired Immunodeficiency Syndrome↗
PubMed2001

Lymphocyte subset populations in children with polysaccharide antibody deficiency following cardiac transplantation.

Pneumococcal polysaccharide (PPS) antibody deficiency occurs in some children immunosuppressed following cardiac transplantation in early childhood. We studied lymphocyte subset populations in these children to identify patterns associated with antibody deficiency, particularly in CD21 + B cells. Lymphocyte surface markers CD3, CD4, CD8, CD19, and CD21 were measured on whole blood by FACS analysis in four patient groups: cardiac transplant patients who did and did not respond to PPS, nontransplanted cardiac patients, and normal controls. Absolute cell numbers were compared with age-related normal ranges. The proportion of children with values below the age-related 25th percentile in each group was compared. Normal controls had significantly more CD3+, CD8+, and CD19+ cells, even when age-related differences were accounted for. Control groups had significantly more CD19 cells than transplant patients and transplanted PPS responders and cardiac controls had more mature B cells (CD21+) than transplanted PPS nonresponders. PPS antibody deficiency following pediatric cardiac transplantation may be related to an immaturity in B cells due to immunosuppression commenced in early childhood.

Adolescent↗
PubMed2000

Changes in lymphocyte subsets during pregnancy and post-partum in cases of beginning eclampsia.

AIMS: The goal of the present retrospective study was to examine the peripheral blood lymphocytes for expression of phenotypic and activation markers concerning the development of hypertension in pregnancy. METHODS: 16 women (aged 25-43 years; mean 35.1) developing hypertension in the third trimester (week 25-34) have had blood samples taken in the first (< 14 weeks), the second (week 14-23), the third trimester (week 24-35), in late pregnancy (week 36-termination of pregnancy) and within 1 week post-partum, The control group consisted of 16 age-matched pregnant healthy women, who underwent the same regime. All blood samples were taken in the morning, stored at room temperature and stained within 6 hours and measured within 24 hours. Kruskal-Wallis analysis of variance between both groups was done with multiple comparison according to Dunn. RESULTS: Comparing both groups, the total white cell count was significantly increased in all pregnancies and post-partum. In case of hypertension in pregnancy the cell numbers of suppressor/cytotoxic (CD 8+) and CD 56(+)-activated T cells showed a significant increase in the first trimester (< 14 weeks) [p < 0.05] and decreased thereafter to normal values. In the second trimester (week 14-23) helper/inducer lymphocytes and CD 56+/CD 3+ lymphocytes decreased in case of pre-ecclampsia and cytotoxic lymphocytes elevated [p < 0.05]. In the third trimester (week 24-35) there was no difference in both study groups and in late pregnancy (week 36-termination) there were only small differences without statistical significance. Within 1 week postnatal the value of Il-2 receptor T lymphocytes decreased in the group of pre-eclampsia in comparison to normal pregnancies [p < 0.05]. CONCLUSIONS: Regarding the major changes in activated T cells in both study groups no specific pattern of lymphocyte subsets in case of pre-eclampsia could be found in comparison to healthy pregnant women. Further investigations should focus on functional activation and/or suppression of the cellular immune system. Perhaps this could lead to a screening test for pre-eclampsia in future, which is non-invasive for the patient and economic for our social community because it might reduce medical costs.

Adult↗
PubMed1990

Lymphocyte subsets during the first hours and days after a 2.5 h running test.

After a 2.5 h running test on eight healthy young males the lymphocyte subsets in peripheral blood were analyzed by flow cytometry. The analysis was carried out immediately post-exercise, after a 1 h and 3 h interval as well as a one day, a two day and five day interval. Lymphocyte subpopulations were also measured in five control subjects who did not exercise. Compared with the pre-exercise level the total lymphocyte and T-cell count was decreased 1 h and 3 h after the run and one and two days after exercise (p less than 0.01). The absolute number of monocytes and B-lymphocytes fell significantly (p less than 0.01) on the first and second day after exercise. No consistent change of helper-/suppressor-inducer T-lymphocytes (CD4+) and cytotoxic-suppressor T-cells (CD8+) cells was observed immediately after exercise. One and 3 h later, however, the absolute number of both cell types dropped below pre-exercise values (p less than 0.01). The decrease of the CD8+ cells was more pronounced, causing an increase of the CD4+ to CD8+ ratio (p less than 0.01). Among the CD4+ cells only the Leu 8+ subpopulation showed a relative increase 1 h after the exercise (p less than 0.01) while the Leu 8- population remained unaffected. 1 h and 3 h after the end of the run there was a significant fall of the absolute number and percentage of natural killer cells (Leu 7+) and cytotoxic T-cells (CD8+ Leu 7+) (p less than 0.01). These cells remained low during the first and second day after the exercise (p less than 0.01). In the control subjects the changes of cell counts for all cells examined were much smaller than in the runners. The results indicate that strenuous and prolonged exercise causes a delayed redistribution of lymphocyte subpopulations with a reduction of lymphocytes and particularly of natural killer and cytotoxic cells beginning 1 h after the exercise followed by a reduction of monocytes 24 h later. The percentage increase of CD4+ cells 1 h after the exercise could be explained by an increase of the CD4+ Leu 8+ subpopulation.

Adult↗
PubMed1992

Pristane induced arthritis in mice. IV. Immunotherapy with monoclonal antibodies directed against lymphocyte subsets.

Pristane induced arthritis (PIA), a seropositive experimental disease model in mice, was used to investigate the influence of immunotherapy with monoclonal antibodies against lymphocyte subsets. Treatment with L3T4, a monoclonal antibody specific for murine CD4+ T cells, significantly reduced the incidence of pristane arthritis, and delayed the disease onset. Monoclonal antibody to Lyt2, the murine CD8+ T cell marker, significantly reduced the levels of rheumatoid factor in pristane injected animals compared with controls, but did not influence the clinical course of PIA. Our experiments demonstrate the ability of anti-CD4 antibodies to modify the course of PIA, and provide support for the hypothesis that CD4+ T lymphocytes have an important role in the pathogenesis of this experimental autoimmune arthritis.

Animals↗
PubMed1993

Cardiopulmonary bypass and cellular immunity: changes in lymphocyte subsets and natural killer cell activity.

To investigate whether cell-mediated immunity responses are suppressed or activated by the effect of cardiopulmonary bypass (CPB), we studied peripheral blood lymphocyte subsets and antibody-dependent cell-mediated cytotoxicity in 52 adult patients who had undergone open heart operations. Lymphocyte function also was studied with regard to mixed lymphocyte reaction, which indicates the amount of DNA synthesis of lymphocytes, and natural killer (NK) cytotoxicity, which represents the killing activity of NK cells on the tumor cells (K-562), in 11 patients. The total T lymphocyte (OKT3+ and OKT11+) number showed no significant change during CPB. Suppressor/cytotoxic T cell (OKT8+) and NK cell (Leu7+ and Leu11+) numbers were found to be remarkably increased. However, helper/inducer T cell (OKT4+) and B cell (Leu12+) numbers were decreased during CPB. Antibody-dependent cell-mediated cytotoxicity was elevated during CPB. All of these changes were almost returned to the preoperative levels by the seventh day after operation. Mixed lymphocyte reaction and NK cytotoxicity were also activated during CPB. The results show that heart operations in which cardiopulmonary bypass is used are associated with activation of cytotoxic cell-mediated immunity.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1995

Varied effects of thoracic irradiation on peripheral lymphocyte subsets in lung cancer patients.

To investigate the influence of thoracic irradiation on immunological competence in patients with lung cancer, we examined the changes in peripheral blood lymphocyte subsets in 15 patients before and after radiation therapy by two-color flow cytometry techniques. After radiation therapy, the percentage and the absolute number of CD4+CD45RA+ cells (naive T cells) and CD56+ and/or CD16+ cells (NK cells) decreased. The percentage of CD4+human leukocyte antigen-DR(HLA-DR)+ cells (activated CD4T cells) and CD8+HLA-DR+ cells (activated CD8T cells) increased, although the absolute number did not change significantly. Naive T cells may be more selectively damaged than memory T cells by thoracic irradiation, through their recirculation behavior. The reduction of natural killer (NK) cells is disadvantageous for anti-tumor immunity. The percentage of HLA-DR positive T lymphocytes was significantly increased, and thus the possibility of HLA-DR enhancement by irradiation cannot be excluded. Therefore, thoracic irradiation has numerous varied effects on the immunological system of lung cancer patients.

Adult↗
PubMed1996

Evaluation of a novel stable whole blood quality control material for lymphocyte subset analysis: results from the UK NEQAS immune monitoring scheme.

The UK NEQAS immune Monitoring Scheme (UK NEQAS) evaluates the performance of laboratories routinely performing T-lymphocyte subset analysis on HIV-infected individuals. The scheme originally issued fresh whole blood, but a significant problem was that of analyte stability, especially 36 h postphlebotomy. To circumvent this problem, we have developed a novel stabilisation procedure that ensures retention of leucocyte light scatter and immunological staining characteristics for up to 300 days. In addition, the stabilised whole blood preparation is fully compatible with flow cytometer technology, incorporating either whole blood lysis or "no wash, no lyse" techniques. The ranges of interlaboratory coefficient of variation for the stabilised material are now tighter than those previously obtained with fresh whole blood. Development of this novel material has enabled overseas laboratories to participate in the UK NEQAS immune Monitoring Scheme and could in the future lead to the production of reference and/or calibration reagents for leucocyte immunophenotyping.

B-Lymphocytes↗
PubMed2003

Flow-cytometric analysis of T-lymphocyte subsets in sinistral and dextral patients with gingivitis.

The aim of this study was to determine whether there was any change in T-lymphocyte subsets in sinistral and dextral patients with gingivitis. The study was carried out on 36 patients (16 males and 20 females) with gingivitis. The age of the patients ranged from 16 to 25 (mean age = 18.50 +/- 3.85). Patients were divided into two equal groups according to their right or left hand use. Being right- or left-handed was determined with Edinburgh Handedness Inventory (Oldfield). At the beginning of the study, gingival index (GI-Löe-Silness) and plaque index (PI-Silness-Löe) scores were recorded in order to assess the gingival tissue health in patients. At the same time, the biopsy samples were taken from the gingival pocket wall tissues at sites of gingivitis. Then, CD4+ and CD8+ lymphocyte and CD4/CD8 ratio values were determined using flow-cytometry in the biopsy samples. The two groups were compared by using Student's t-test. The normal value in peripheral blood of CD4+ lymphocyte and that of CD8+ lymphocyte are 25-29% and 19-48%, respectively. According to flow cytometry findings, in both sinistrality and dexterity with gingivitis, CD+ and CD8+ lymphocyte values were under the normal value while the CD4/CD8 rate was within normal distribution interval. CD4+ lymphocyte values observed in the sinistral patients were found to be lower than those in the dextral patients. The difference between the CD8+ lymphocyte values in left-handed patients and that obtained in right-handed patients was not found to be statistically significant while the difference between the CD4+ lymphocyte values in left-handed patients and that obtained in right-handed patients was found to be statistically significant (p < .05). In addition, the difference between the CD4/CD8 rate obtained in left-handed patients and that obtained in right-handed patients was found to be statistically very significant (p < .001). Consequently, these findings suggested CD4+ lymphocyte value and CD4/CD8 rate was lower in sinistrality. Sinistrality and dexterity may play an important role in local immune response.

Adolescent↗
PubMed1987

Lack of prognostic significance of T-lymphocyte subset counts in B-cell chronic lymphocytic leukaemia.

In the 50 newly diagnosed, unselected, untreated B-CLL patients, the absolute numbers of blood T cells, T-helper cells, and T-suppressor/cytotoxic cells were by flow cytometric counting of mononuclear cells labelled with the monoclonal antibodies Leu5 (T cells), Leu3a (T-helper cells), and Leu2a (T-suppressor/cytotoxic cells). These estimations and the serum concentrations of IgG, IgA, and IgM were correlated to clinical stage (International Workshop System) and pretreatment observation time. For all patients together, the mean counts of Leu5+, Leu3+, and Leu2+ cells were significantly increased compared with the mean counts in 12 healthy controls (Mann-Whitney). In patients with advanced disease (stage B + C), both T-subset mean cell counts were significantly increased, whereas in patients with early-stage disease (stage A), although some high T-helper cell counts were noted, only the T-suppressor/cytotoxic mean cell count increase reached significance. Thus a trend was observed of a more frequent T-suppressor/cytotoxic cell predominance in early-stage disease, which is the opposite of the findings in most other prognostic studies. However, there was no significant difference in pre-treatment observation time according to T-helper: T-suppressor cell ratio below vs. above 1.0, irrespective of stage, whereas according to clinical stage, the pretreatment observation time in stage A was highly significantly longer than in stage B + C (logrank test). Thus, no independent prognostic significance of T-subset counts was found as judged by pretreatment observation time. No correlation was found between the occurrence of hypogammaglobulinaemia, T-subset ratios or T-subset counts.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1984

Lymphocyte subsets and inflammatory indices in synovial fluid and blood of patients with rheumatoid arthritis.

Lymphocyte subsets defined by monoclonal antibodies, C reactive protein (CRP), immune complexes (IC), rheumatoid factor (RF), C3, C4 and neutrophil and lymphocyte numbers were measured in synovial fluid (SF) and blood samples from 11 patients with rheumatoid arthritis. SF showed an increased percentage of T cells, Ia+ cells and OKT8+ cells and a reduced percentage of B cells and OKT4+ cells, when compared with blood. Reduced levels of CRP, RF, C3 and C4 were found in SF compared with blood. Comparisons between cellular subsets and other indices in SF revealed a positive correlation between neutrophil numbers and IC, CRP, and RF with a negative correlation between neutrophil numbers and numbers of T cells and OKT8+ cells. A similar negative correlation was found in blood between OKT8+ cells and both CRP and RF. These results indicate an association between increasing disease activity and a lack of suppressor/cytotoxic cells in both circulating and intraarticular compartments. An additional important finding was the lack of correlation of Ia+ cells in both SF and blood with neutrophil numbers, CRP, IC, C3 and C4 or RF.

Adult↗
PubMedDate not supplied

Imbalanced "memory" T lymphocyte subsets and analysis of dendritic cell precursors in the peripheral blood of adult patients with Langerhans cell histiocytosis.

OBJECTIVES: To investigate the phenotype of lymphocytes and dendritic cell precursors in the peripheral blood of adult patients with histiocytosis X. METHODS: Data were obtained on patients with histiocytosis X treated in La Pitié-Salpetrière Hospital. Peripheral blood mononuclear cells from 10 patients (4 with unifocal and 6 with disseminated disease) were studied by flow cytometry. A method was set up to detect circulating Langerhans cells, dendritic cells and their precursors. RESULTS: An abnormal repartition of "memory" T lymphocyte subsets was observed, with a significant decrease of CD4CD45RO and CD8CD45RO and a reciprocal increase of CD4CD45RA "naive" cells, while CD4+ cells displaying the accessory molecule CD28 were decreased in some patients. These abnormalities disappeared in vitro after triggering of the CD3 and CD28 molecules in the absence of antigen presenting cells, hence demonstrating that there was no constitutive defect in the capacity of CD4+ and CD8+ T cells to convert from the CD45RO- to the CD45RO+ isoform. Langerhans cells were undetectable in the peripheral blood, and dendritic cells and their precursors were present in normal proportions (0.5 +/- 0.2% and 2.8 +/- 1.2%, respectively), but the latter were more numerous (4% and 6% of the PBMC) in the two patients with the more severe form of the disease. CONCLUSIONS: We found in these patients some T lymphocyte phenotype abnormalities which suggest alterations in antigen-driven activation processes. The number of dendritic precursor cells was not consistently elevated in the peripheral blood from histiocytosis X patients.

Adult↗
PubMed1990

Analysis of T helper and suppressor lymphocyte subsets in relation to the clinical stage of solid neoplasms.

Neoplastic disease affect the immunity in cancer patients. The immune alterations in human neoplasms, however, need to be further defined. The present study was carried out to analyze T lymphocyte subsets in patients with solid tumors. The study included 93 patients suffering from early or metastatic solid neoplasms. T helper and T suppressor subsets were measured on venous blood samples by using flow cytometry and monoclonal antibodies. As controls, 58 healthy subjects were included in the study. The T mean helper/suppressor ratio (CD4/CD8) was significantly lower in metastatic cancer patients with respect to that observed either in controls or in patients without metastases. A low CD4/CD8 ratio was seen in 25 of 93 cancer patients (26.9%), 8 of whom had no metastases, while the other 17 showed a metastatic disease. Within the nonmetastatic group, the decline in the CD4/CD8 ratio was due to increases in the T suppressor subset alone in 7. On the contrary, the percentage of cases with decreased T helper subset was significantly higher in metastatic than in the nonmetastatic patients. The results of this study suggest that the decrease in the CD4/CD8 ratio mainly depends on an increase in T suppressor cells in patients without metastases whereas it is due to a decrease in the T helper subset in most patients with metastatic diseases.

Adult↗
PubMed1989

[A study of lymphocyte subsets in human normal tonsil and lymph node].

A series of T and B lymphocyte specific monoclonal antibodies was used to determine the localization of lymphocyte subpopulation in frozen and paraffin tissue sections of human normal tonsil and lymph node by means of immunocytochemical technique. In the paracortical and interfollicular area of tonsil and lymph node, most lymphocytes reacted with Leu 1, Leu 3 a, Leu 4 and OKT4. The numbers of Leu 2 a and OKT8 positive cells were rare in tissue. These cells were not only limited in paracortical area, they also appeared in considerable numbers in medullary cords of lymph nodes. Leu 2 a and OKT 8 positive cells decreased with prominent follicular hyperplasia of tonsils. In addition, substantial leu 3 a and Leu 4 cells were found in the germinal centers. This finding supports the importance of these lymphocyte subsets in regulation of human immune response. In the mantle zone of secondary follicles, the majority of lymphocytes were positive for OKB 2 and BA 1, whereas, the IgM positive cells were predominately observed in the cytoplasma and extracellular substance of B lymphocytes in the germinal centers, but the lymphocytes bearing sIgM were rarely observed. In the mantle zone, the IgM were frequently found on the surface of membrane of small lymphocytes, however, the staining intensity was much than that in the germinal centers.

Antibodies, Monoclonal↗