Magdolna Aleksza

Elevated rate of Thelper1 (TH1) lymphocytes and serum IFN-γ levels in psoriatic patients

Abstract Several disorders are known to be associated with altered Thelper1/Thelper2 (T H 1/T H 2) cytokine balance. Psoriasis is characterized by increased systemic and local production of T H 1 and pro-inflammatory cytokines. Furthermore recent data indicate the dominant presence of T H 1 lymphocytes in the circulation and T H 1 and Tcytotoxic1 (T C 1) cells in lesional skin of psoriatic patients. In order to assess the systemic T H 1/T H 2 imbalance in psoriasis most of the studies so far tested isolated peripheral mononuclear cells. As a new approach we applied a whole blood flow cytometric assay to determine the rate of circulating T H 1/T H 2 and T C 1/Tcytotoxic2 (T C 2) lymphocytes based on their intracellular IFN-γ, IL-4 and IL-10 expression. Besides, serum levels of these cytokines were determined in healthy controls and psoriatic patients by commercial ELISAs. In psoriatic patients we found significantly ( P + /IFN-γ + lymphocytes (30.3±8.8%) while the percent of CD4 + /IL-4 + cells (0.37±0.31%) were significantly ( P + /IFN-γ + : 20.1±7.3% and CD4 + /IL-4 + : 0.78±0.44%). The IL-10-positive CD4 + and CD8 + cells also had higher rate in psoriasis, but the difference between patients and controls was not significant, similarly to the rate of CD8 + /IFN-γ + and CD8 + /IL-4 + lymphocytes. Beside cellular expression, serum IFN-γ levels were also significantly higher (control: 4.9±6.4 pg/ml; psoriatic patients: 35.9±47.0 pg/ml; P H 1/T H 2 balance in psoriasis measured in non-separated whole blood T cells.

Measurement of natural (CD4+CD25high) and inducible (CD4+IL-10+) regulatory T cells in patients with systemic lupus erythematosus

Abnormalities of regulatory T cells may play an important role in the loss of self-tolerance, which is a major characteristic of lupus. The objective of this study was to determine the ratio and the number of natural CD4+CD25highFoxp3+ and inducible CD4+IL-10+ regulatory T cells in lupus patients and to search correlation with disease activity. Seventy-two Hungarian lupus patients were enrolled in the study. Fourty-one age- and sex matched healthy donors served as controls. Flow cytometry was used for the quantification of CD4+CD25high Foxp3+ (nTreg) and CD4+IL-10+ (iTreg) cells. The ratio (3.06 ± 1.45%) and the number (0.019 ± 0.012 × 109/L) of nTreg cells decreased in lupus significantly (P < 0.001 in both) as compared to normal controls (4.26 ± 1.01% and 0.039 ± 0.017 × 109/L). The ratio of iTreg cells were significantly higher in patients than in controls (20.92 ± 14.02% versus 15.49 ± 11.65%, P < 0.03), but the number of these cell type did not differ in significant manner (0.314 ± 0.236 × 109/L versus 0.259 ± 0.183 × 109/L). The 19 active patients were characterised by significantly higher disease activity index (SLEDAI 8.63 ± 2.95 versus 1.74 ± 1.68, P < 0.001) and anti-DNA concentration (117.85 ± 145.89 versus 37.36 ± 68.85 IU/mL, P = 0.001) as compered to the 52 inactive patients. Furthermore, active patients required higher dose of methylprednisolon than inactive ones (14.8 ± 10.6 versus 4.8 ± 3.4 mg/day, P < 0.001). However, we did not find statistical significant difference in the number and ratio of the examined cell populations regarding to disease activity. Altered ratio and number of both natural and inducible regulatory T cells may play a role in the pathogenesis of lupus. There are small but appreciable difference in the number of regulatory T cells between inactive patients and healthy controls. It suggests that immunoregulatory deficiencies are present in the inactive stage of the disease also. Lupus (2007) 16, 489—496.

Th1/Th2 imbalance, measured by circulating and intracytoplasmic inflammatory cytokines : Immunological alterations in acute coronary syndrome and stable coronary artery disease

To describe how peripheral immune‐parameters reflect the inflammatory alterations of the atherosclerotic plaques in coronary atherosclerosis. We measured general inflammatory markers C‐reactive protein (CRP) and granulocyte activity, lymphocyte subpopulations and their state of activation, evaluated circulating Th1/Th2‐type cytokines, and specific intracytoplasmic cytokines. We investigated the association of immune‐parameters with disease outcome and mortality. Thirty‐three patients with acute coronary syndrome (ACS), 62 with stable coronary artery disease (CAD) and 58 healthy controls were studied. Peripheral blood lymphocyte subgroups were quantified by flow cytometry, soluble cytokines and autoantibodies were assessed using enzyme‐linked immunosorbent assay (ELISA), while intracellular cytokine levels were measured by flow cytometry after intracellular staining. We found elevated levels of CRP and granulocyte activity in ACS versus CAD (P < 0.001, P = 0.017, respectively). Natural killer (NK) cell percentages were elevated, while percentage of T cells to the total lymphocyte count was slightly decreased in ACS compared to controls (P < 0.0001, P = 0.012, respectively). Both forms of coronary atherosclerosis showed significantly higher percentages of activated T cells than controls when stained for the activation markers HLA‐DR3 and CD69+ (ACS: P < 0.0001, P = 0.002, CAD: P < 0.0001, P = 0.018, respectively). IL‐1, IL‐4 and IL‐10 proved significantly higher in ACS versus controls (P = 0.036, P = 0.01, P < 0.0001 respectively). Th1 to Th2 ratio shifted towards a Th1 dominance in both diseases. Both general proinflammatory markers and activated T cells signify CAD. The orchestrated proinflammatory cascade eventually leads to the development of the disease.

Increased frequency of intracellular interleukin (IL)-13 and IL-10, but not IL-4, expressing CD4+ and CD8+ peripheral T cells of patients with atopic dermatitis.

Summary Background  A number of studies exist demonstrating the increased expression of type 2 cytokines and decreased capacity to produce interferon‐γ (IFN‐γ) in peripheral blood mononuclear cells (PBMCs) of patients with atopic dermatitis (AD).

The severity of systemic lupus erythematosus negatively correlates with the increasing number of CD4+CD25highFoxP3+ regulatory T cells during repeated plasmapheresis treatments of patients

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by increased pathologic autoantibody production. A decrease in the number of CD4+CD25highFoxP3+ regulatory T cells can play a key role in the loss of tolerance to self antigens. Our aim was to determine the absolute number of peripheral CD4+CD25highFoxP3+ T cells in 44 patients with SLE, furthermore, to measure the changes in the number of CD4+CD25highFoxP3+ T cells in 5 patients with severe SLE treated with repeated plasmapheresis for 4–6 days in comparison to the changes in the activity of disease (SLEDAI). Percent of CD4+CD25highFoxP3+ T cells were measured by flow cytometry. The absolute number of peripheral CD4+CD25highFoxP3+ T cells was significantly decreased in the 44 patients with SLE compared to the healthy controls n = 32 (0.012 ± 0.006 vs. 0.038 ± 0.017 G/L, p < 0.05). In the 5 patients with severe SLE the repeated plasmapheresis treatments increased the peripheral number of CD4+CD25highFoxP3+ T cells. As the number of CD4+CD25highFoxP3+ T cells increased during the treatment, the activity of disease (the value of SLE activity index) decreased. In the peripheral blood of SLE patients not only the ratio was decreased (as it was published earlier) but also the absolute number of these regulatory T cells. The repeated plasmapheresis treatments of SLE patients induced a significant increase in the number of peripheral CD4+CD25highFoxP3+ T cells in parallel to the decrease in the values of SLEDAI (the activity of disease). This phenomenon is, among others, possibly due to the elimination of interpheron-alpha and lymphocytotoxic antibodies during plasmapheresis.

Clinical and Immunoserological Characteristics of Mixed Connective Tissue Disease Associated with Pulmonary Arterial Hypertension

We investigated the clinical characteristics and immunoserological alterations in patients with mixed connective tissue disease (MCTD) associated with pulmonary arterial hypertension (PAH). Anti‐U1RNP autoantibodies, anti‐endothelial cell antibodies (AECA) and serum thrombomodulin (TM) as well as von Willebrand factor antigen (vWFAg) concentrations were measured in 25 patients with MCTD associated with PAH and in 154 MCTD patients without PAH. The results showed that the probability of survival was lower in MCTD patients with PAH than in the 154 MCTD‐non‐PAH patients (5‐year survival rate in MCTD with PAH: 73%, versus 96% in MCTD‐non‐PAH; P < 0.01). AECA were more frequently present in the sera of MCTD patients with PAH than in MCTD‐non‐PAH (P < 0.001). Serum TM and vWFAg levels were higher in MCTD‐PAH patients than in MCTD‐non‐PAH patients (TM: P < 0.001; vWFAg: P < 0.001). Significant correlation was noticed between the quantity of AECA and TM level (r = 0.466) as well as the quantity of AECA and vWFAg level (r = 0.550). In conclusion, our results suggest that in MCTD the presence of AECA and endothelial cell activation may play a role in the development of PAH and in the maintenance of obliterative vascular processes.

Opposite roles of protein kinase C isoforms in proliferation, differentiation, apoptosis, and tumorigenicity of human HaCaT keratinocytes

We have previously shown that the protein kinase C (PKC) system plays a pivotal role in regulation of proliferation and differentiation of the human keratinocyte line HaCaT which is often used to assess processes of immortalization, transformation, and tumorigenesis in human skin. In this paper, using pharmacological and molecular biology approaches, we investigated the isoform-specific roles of certain PKC isoenzymes (conventional cPKCα and β; novel nPKCδ and ε) in the regulation of various keratinocyte functions. cPKCα and nPKCδ stimulated cellular differentiation and increased susceptibility of cells to actions of inducers of apoptosis, and they markedly inhibited cellular proliferation and tumor growth in immunodeficient mice. In marked contrast, cPKCβ and nPKCε increased both in vitro and in vivo growth of cells and inhibited differentiation and apoptosis. Our data present clear evidence for the specific, antagonistic roles of certain cPKC and nPKC isoforms in regulating the above processes in human HaCaT keratinocytes.

Altered cytokine expression of peripheral blood lymphocytes in polymyositis and dermatomyositis

Objective: To investigate the intracellular and soluble cytokine levels and T cell subsets in peripheral blood of patients with active and inactive polymyositis and dermatomyositis. Methods: The frequencies of T and B lymphocytes, T helper (Th), and T cytotoxic (Tc) cells and of interferon γ (IFNγ), interleukin (IL)4, and IL10 expression of CD4+ or CD8+ cells were determined by flow cytometry. The concentrations of soluble cytokines were measured with commercial enzyme linked immunosorbent assays. Results: In active dermatomyositis there was a decreased percentage of T (CD3+) lymphocytes and Tc (CD8+) lymphocytes, decreased IFNγ expression of CD4+ and CD8+ cells, but an increase in B and IL4 producing CD4+ lymphocyte frequencies. These prominent changes disappeared in the inactive stage of the disease. In polymyositis no significant change in these lymphocyte subsets or in intracellular cytokine expression could be detected in either the active or the inactive form. The frequency of IL4+/IFNγ+ Th cells was calculated and a significantly increased Th2/Th1 frequency was found in active dermatomyositis, and a decreased frequency in inactive dermatomyositis, compared with the control population. Conclusions: There appears to be a difference between polymyositis and dermatomyositis in the level of peripheral blood lymphocytes and their intracellular cytokine content. These findings provide further evidence for a difference in the pathogenesis of polymyositis and dermatomyositis.

Immunological alterations in newly diagnosed primary Sjögren's syndrome characterized by skewed peripheral T-cell subsets and inflammatory cytokines.

Objectives: To describe how certain peripheral immune parameters reflect the inflammatory alterations in patients with primary Sjögrens syndrome (pSS). We determined lymphocyte subpopulations and their state of activation from peripheral blood, evaluating both soluble serum T‐helper (Th)1/Th2‐type cytokines and intracytoplasmic cytokines. Methods: Forty‐nine patients with newly diagnosed pSS and 40 healthy individuals, all free from immunomodulant or immunosuppressive medication, were studied. Peripheral blood lymphocyte subgroups were quantified by flow cytometry, soluble cytokines were assessed using enzyme‐linked immunosorbent assay (ELISA), and intracellular cytokine levels were measured after phorbol myristate acetate (PMA) stimulation by flow cytometry after staining of intracellular cytokines. Results: Patients with primary SS had higher percentages of activated CD3+/CD69+ T cells than controls. When comparing naïve vs. memory subsets of CD4+ and CD8+ T cells, a shift towards the memory phenotype was observed for both. Natural killer (NK) cell and NK T‐cell (NKT) percentages and Th0 and Th1 cell numbers were increased in patients compared to controls. Among circulating cytokines, interferon (IFN)‐γ was high, whereas interleukin (IL)‐10 was decreased in SS when compared to controls. Conclusions: SS, considered as a systemic autoimmune disease, is characterized by a complex interplay of various cytokines and immune cells. The skewed T‐cell subsets and cytokine imbalance play important roles in an orchestrated proinflammatory cascade.

Measurement of intracellular interferon-gamma and interleukin-4 in whole blood T lymphocytes from patients with systemic lupus erythematosus

Contradictory data are available about the dominance of T-helper 1 (T(H)1), or T-helper 2 (T(H)2) cytokines in systemic lupus erythematosus (SLE). Therefore, intracellular interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) production of T lymphocytes was measured in whole blood of healthy donors and active and inactive SLE patients by flow cytometry. The percentage of IFN-gamma and IL-4 positive cells was low (<1%) in unstimulated samples of the healthy controls, while that of IFN-gamma and IL-4 positive cells in the stimulated cells was 25.2+/-10.6% and 0.6+/-1.5%, respectively. No significant difference was found between SLE patients and healthy controls and between active and inactive patients in these parameters either in the unstimulated or in the stimulated samples. One patient with severe disease had as high as 11.8% IL-4 positive cells and 12.5% IFN-gamma positive cells in the stimulated samples, but after the initiation of intensive corticosteroid and cytostatic therapy, the percentage of IL-4 positive T cells decreased (4.76%) while that of IFN-gamma positive T cells increased (47.91%). We conclude that the intracellular IL-4 and IFN-gamma expression of T lymphocytes does not differ markedly between SLE patients and healthy controls, with the possible exception of severe disease, when marked IL-4 overproduction may exist beside low IFN-gamma production. Furthermore, corticosteroid and cytostatic therapy might normalize this altered IFN-gamma/IL-4 ratio.