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The aetiology and progression of systemic lupus erythematosus (SLE) resulted from a complex sequence of events generated both from genetic and epigenetic processes. In the current research, the effect of methyl-supplemented nutrition on the development of SLE was studied in the pristane-induced mouse model of the disease. The results clearly demonstrated decreased anti-dsDNA antibody and proteinuria levels, modulation of cytokines and protected renal structures in the group of treated mice. An additional increase in the DNA methylation of mouse B lymphocytes was also observed. The beneficial effect of the diet is due to the methyl-containing micronutrients with possible anti-inflammatory and immunomodulating effects on cell proliferation and gene expression. Since these components are responsible for maintaining the physiological methylation level of DNA, the results point to the central role of methylation processes in environmentally triggered lupus. As nutrition represents one of the major epigenetic factors, these micronutrients may be considered novel agents with significant therapeutic outcomes., (© 2024 John Wiley & Sons Ltd.)

IgA nephropathy (IgAN) diagnosis remains largely based upon immunohistologic detection of IgA- and IgG-containing glomerular deposits in renal mesangial cells, and little is known about the underlying pathogenic mechanisms. This study examines the putative contribution of B cell types, including the Breg type, to IgAN pathogenesis. Twenty-four patients with IgAN and proteinuria (Group A: <3.5 g/24 h, n = 13; Group B: >3.5 g/24 h, n = 11) and 10 healthy controls were enrolled. The frequencies of B cell subtypes in venous blood were measured by flow cytometry. Galactose-deficient IgA1 was measurement by ELISA. Needle biopsies were analysed by histology and immunofluorescence microscopy. Correlation between clinical features and B cell subtypes, including the regulatory B (Breg) cells, and Breg cell-derived immunomodulatory cytokine IL-10 was assessed by Spearman's rank correlation test. IgAN patients had significantly higher frequencies of CD27(+) CD19(+) , CD38(+) CD19(+) , CD86(+) CD19(+) and CD5(+) CD19(+) B cells than the healthy controls, but significantly lower levels of Breg cells and intracellular expression of IL-10 protein in the Breg subtype. Serum IgA concentration positively correlated with CD27(+) CD19(+) B cell frequency and negatively correlated with IL-10(+) Breg cell frequency in IgAN patients, and the percentage of CD19(+) CD5(+) CD1d(+) in CD19(+) cells was negatively correlated with the level of serum Gd-IgA1. Furthermore, the frequencies of CD19(+) CD38(+) and CD19(+) CD86(+) in the CD19(+) subpopulation negatively correlated with the estimated glomerular filtration rate of IgAN patients. Several of the CD19(+) B cell subtypes and the IL-10(+) Breg cells are differentially expressed in IgAN patients and may contribute to the disease pathogenesis., (© 2013 John Wiley & Sons Ltd.)

E2A has been shown to be an important transcription factor downstream of the T-cell receptor (TCR) signal during T-cell development. The TCR signal is known to elicit different cellular responses at different stages of T-cell development. Whether E2A is still required for normal TCR signalling in mature T cells is unknown. Here we examined T-cell function after disruption of the E2A gene exclusively in the T-cell lineage. The conditional E2A-deficient mice show enhanced humoral immunity to a T-dependent antigen. We further show that E2A is involved in regulating TCR-induced T-cell proliferation events. However, E2A seems to play opposite roles in naïve and effector T cells. In the absence of E2A, TCR-induced proliferation is increased in naïve T cells and decreased in effector T cells. At older ages, these mice frequently develop antinuclear antibodies and proteinuria. Our studies suggest that E2A regulates T-cell function and the loss of E2A may promote age-dependent autoimmune diseases.

Haemolytic uraemic syndrome (HUS) associated with Escherichia coli O157:H7 is the commonest cause of acute renal failure (ARF) in childhood. Production of verotoxin by the organism is pivotal in the pathogenesis of the disease. Verotoxin binds to a receptor on blood and endothelial cells, expressed as the P1 blood group antigen on red blood cells. A protective effect of the P1 phenotype has been proposed in this disease. This study investigates prognostic factors and the relationship between outcome and P1 phenotype in 27 cases of diarrhoea-associated HUS. A poor outcome as defined by the presence of chronic renal failure (CRF), hypertension or proteinuria on 6 month follow-up was associated with the age of the patient at presentation and with the following clinical markers: maximum WBC and duration of raised WBC, duration of anuria and duration of need for dialysis. None of these outcome measures or prognostic factors, and no extra-renal manifestations of the disease were associated with P1 phenotype.

We have studied the role of complement in a model of glomerular inflammation induced by the in situ formation of immune complexes along the glomerular basement membrane. In C3-deficient mice, produced by homologous recombination, immune complex formation occurs initially in the subendothelial site and progresses slowly to the subepithelial position, whereas wild-type mice do not develop subendothelial deposits. In addition, the accumulation of electron-dense deposits is greater in the complement-deficient mice. Complement therefore influences glomerular handling of immune complexes, possibly because of changes in the physiochemical characteristics of the immune complexes. However, despite evidence of complement activation in the wild-type mice, as demonstrated by immunohistochemical detection of C3, C4 and C9, the degree of proteinuria was similar in C3-deficient mice. We conclude that, although complement is required for the normal glomerular metabolism of immune complexes, other, complement-independent, factors are involved in the generation of glomerular injury in this model.

In Brown-Norway (BN) rats mercuric chloride induces an autoimmune disease characterized by an increase in serum IgE concentration, and by the production of anti-glomerular basement membrane antibodies responsible for a glomerulonephritis with a heavy proteinuria. (i) This disease results from a B-cell polyclonal activation probably due to frequent anti-class II T cells. (ii) The self limitation observed in this model is associated with both a decrease in the frequency of anti-class II T cells and the emergence of CD8+ T cells able to suppress these autoreactive T cells. (iii) In Lewis (LEW) rats which do not develop autoimmunity, HgCl2 provokes the appearance of non-antigen-specific CD8+ T cells responsible for a depression of T-cell functions. The aim of this work was to test the effect of treatment with an anti-CD8 monoclonal antibody (MoAb) in both BN and LEW rats. Anti-CD8 MoAb-treated rats were effectively depleted in CD8+ T cells. However, neither the induction nor regulation phases of mercury-induced autoimmunity were modified in BN rats. Mercury-induced immunosuppression in LEW rats was abrogated; however, depletion in CD8+ T cells did not allow the disease to occur in that strain. Finally, CD8 depletion induced in normal BN rats the appearance of rare anti-class II T cells showing that these cells are normally present in that strain but negatively controlled by suppressor T cells.

Suppressor cell activity (SCA) was analysed in 28 patients with lipoid nephrosis (LN) and 11 patients with chronic proliferative glomerulonephritis (CGN). We have assessed the ability of peripheral blood lymphocytes (PBL) stimulated by concanavalin A (Con A) to inhibit the proliferative response of normal allogeneic lymphocytes by both Con A and phytohaemagglutinin (PHA). It was found that the LN patients in the earlier phase of relapse had significantly increased levels of suppression index (SI) were compared with the values obtained with normal controls. In contrast, the mean suppression values in the PBL from LN patients in remission and CGN patients with or without nephrotic syndrome, whether the mitogen used was Con A or PHA, were similar to those of the control subjects. Moreover, when individual patients were followed through their clinical illness, LN patients had high levels of SI, particularly in the beginning of acute exacerbations; the SI levels than decreased sharply in the latter phase of relapse and again increased to relatively normal levels with the onset of clinical remission. These in vitro findings suggest that there exists an alteration in Con A-induced SCA in a group of patients with LN.

Cellular and humoral responses were ivestigated following human glomerular basement membrane a-d streptococcol Type 12 membrane injections in rabbits. Using the leucocyte migration inhibition test and double diffusion in agar gel, cross-reactivity between the antigens was evident, though neither antigen induced significant proteinuria or nephritis in the dosages given.

Mice selectively bred to produce either high or low affinity antibody to protein antigens were injected daily with bovine serum albumin (BSA) and studied for the development of chronic antigen-antibody complex disease. After 41-44 injections of BSA, evidence of circulating antigen-antibody complexes and renal localization of complexes was obtained in both lines. However, low affinity mice had significantly higher levels of circulating complexes than high affinity mice. Impairment of renal function was seen in low affinity mice but not in high affinity mice and there was significantly more complex deposition in the glomeruli of low compared to high affinity mice. Furthermore, the pattern of localization of complexes was predominantly mesangial in high affinity mice but in low affinity mice the deposition was both mesangial and in the glomerular basement membrane. The role of antibody affinity in the induction of chronic antigen-antibody complex disease is discussed in the light of these results.

Wistar rats rendered cirrhotic with carbon tetrachloride excreted significant proteinuria and hematuria. Serum levels of IgA and IgG were significantly elevated in cirrhotic animals. They showed mild mesangial proliferation and immunofluorescent studies revealed deposits of IgA and IgG predominantly in mesangial areas and along capillary walls. These findings were very similar to those seen in patients with hepatic cirrhosis or IgA nephropathy. The deposits of IgA were also found in hepatic tissue from cirrhotic animals. The intensity and distribution of glomerular IgA deposits were not diminished after treatment with acid buffer. These results suggest that glomerular IgA are IgA polymers and decreased hepatic clearance of hepatic IgA polymers may be responsible for the glomerular deposition of IgA.

Three cases are described showing a seasonal exacerbation of their nephrotic syndrome in association with an atopic trait and grass pollen allergy. The first patient has a history of four consecutive seasonal relapses each requiring steroid therapy. Following a course of desensitization injections he has now been free of relapse for 3 consecutive years. The second patient has also had a recurrent steroid-sensitive nephrotic syndrome often associated with the pollen season and allergic rhinitis. In this patient a course of cyclophosphamide has reduced his tendency to relapse. The third patient who has been on continuous prednisone therapy shows a seasonal increase in proteinuria. Serum changes in the first two patients include: a seasonal rise in total and grass pollen specific IgE; the continued presence of grass pollen specific IgG throughout the year but with a reduction during the pollen season in association with a more pronounced fall in the total IgG level; a depression in the C3 level in association with each major relapse; a mild rise in the I-K titre and a positive result in the Clq test for circulating complexes. A renal biopsy performed on the first patient when in relapse showed minor histological changes only and IgG, IgM, IgA, IgD, IgE, C3 and fibrinogen were undetectable by immunofluorescent examination. The probable mechanism for the development of proteinuria in these patients is discussed.