IL-37 inhibits the production of pro-inflammatory cytokines in MSU crystal-induced inflammatory response

Acute gouty arthritis (AGA) is an auto-inflammatory disease characterized by resolving spontaneously, which suggests that negative feedback loops control inflammatory and immunological responses to monosodium urate (MSU) crystals. By now, the molecular mechanism for spontaneous resolution of acute GA remains unclear; this study was undertaken to evaluate whether IL-37 is involved in spontaneous resolution of AGA. A total of 45 acute GA (AGA),29 non-acute GA (NAGA) male patients and 82 male health control (HC) were involved in this study, we measured IL-7 expression in the peripheral blood mononuclear cells (PBMCs), together with levels of IL-1β, IL-6, IL-10, TNF-α and TGF-β1 in the serum. Further, we either inhibited IL-37 expression in human PBMCs with siRNA or over-expressed the cytokine in human macrophages. Pro-inflammatory cytokine IL-1β, IL-6, and TNF-α expressions were significantly higher in the AGA group than in the NAGA or HC group (P?<?0.05, respectively). However, anti-inflammatory IL-37, TGF-β1, and IL-10 were greater in the NAGA group than in the AGA and HC groups (P?<?0.05, respectively). Expression of IL-37 in MSU crystal-treated macrophages inhibited the expression of pro-inflammatory cytokines, whereas the abundance of these cytokines increased with silencing of endogenous IL-37 in human blood cells. However, anti-inflammatory TGF-β1 and IL-10 expressions in these supernatants were unaffected by over-expression or knockdown of IL-37. Our study indicates that IL-37 is an important anti-inflammatory cytokine in AGA by suppressing the production of pro-inflammatory cytokines. Thus, IL-37 may provide a novel research target for the pathogenesis and therapy of GA.     

Oral histone deacetylase inhibitor synergises with T cell targeted immunotherapy to preserve beta cell metabolic function and induce stable remission of new-onset autoimmune diabetes in NOD mice

Aim/hypothesis

Combination therapy targeting the major actors involved in the immune-mediated destruction of pancreatic beta cells appears to be an indispensable approach to treat type 1 diabetes effectively. We hypothesised that the combination of an orally active pan-histone deacetylase inhibitor (HDACi: givinostat) with subtherapeutic doses of CD3 antibodies may provide ideal synergy to treat ongoing autoimmunity.

Methods

NOD mice transgenic for the human CD3ε (also known as CD3E) chain (NOD-huCD3ε) were treated for recent-onset diabetes with oral givinostat, subtherapeutic doses of humanised CD3 antibodies (otelixizumab, 50 μg/day, 5 days, i.v.) or a combination of both drugs. Disease remission, metabolic profiles and autoreactive T cell responses were analysed in treated mice.

Results

We demonstrated that givinostat synergised with otelixizumab to induce durable remission of diabetes in 80% of recently diabetic NOD-huCD3ε mice. Remission was obtained in only 47% of mice treated with otelixizumab alone. Oral givinostat monotherapy did not reverse established diabetes but reduced the in situ production of inflammatory cytokines (IL-1β, IL-6, TNF-α). Importantly, the otelixizumab + givinostat combination strongly improved the metabolic status of NOD-huCD3ε mice; the mice recovered the capacity to appropriately produce insulin, control hyperglycaemia and sustain glucose tolerance. Finally, diabetes remission induced by the combination therapy was associated with a significant reduction of insulitis and autoantigen-specific CD8⁺ T cell responses.

Conclusions/interpretation

HDACi and low-dose CD3 antibodies synergised to abrogate in situ inflammation and thereby improved pancreatic beta cell survival and metabolic function leading to long-lasting diabetes remission. These results support the therapeutic potential of protocols combining these two drugs, both in clinical development, to restore self-tolerance and insulin independence in type 1 diabetes.

     

Relationship between serum pro- and anti-inflammatory cytokine and growth factor concentrations with the age and gender adjusted prevalence of diabetes and pre-diabetes

The main goal of the present study is to compare the serum pro- and anti-inflammatory cytokines and growth factor profile (IL-1α, IL-1β, IL-2, IL-6, IL-8, IFN-γ, MCP-1, TNF-α, IL-10, IL-4, VEGF, and EGF) in individuals with diabetes or pre-diabetes and control subjects matched for age and gender. This study included 270 normal control subjects, 41 pre-diabetics, and 104 diabetic subjects. Demographic and anthropometric characteristics and serum biochemistry parameters, smoking status, and blood pressure were determined. Serum cytokine and growth factor measurements were performed using a multiplex biochip array based method. After removing the effects of confounders such as age, sex, smoking, BMI, serum triglyceride and cholesterol, hypertension, and treatment with anti-diabetic drugs, serum IL-4 (p = 0.015), IL-1α (p = 0.031), and VEGF (p = 0.012) were significantly associated with the presence of diabetes mellitus. The presence of pre-diabetes was positively associated with serum IL-4 (p < 0.001), and IL-1α (p = 0.026). We have found a positive association between serum IL-1α, and IL-4, and a negative association of serum VEGF with the presence of diabetes, or pre-diabetes.     

Clinical and laboratory aspects of dyslipidemia in Brazilian women with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is associated with dyslipidemia, atherosclerosis, and cardiovascular disease. In this study, we investigated the presence of dyslipidemia in Brazilian SLE patients by evaluating their lipid profile and immune status, including the production of autoantibodies and cytokines involved in atherogenesis. Ninety-four female SLE patients participated in this study and, based on their lipid profile, were classified as dyslipidemic or not. All were tested for antinuclear antibodies (ANAs), antiphospholipid antibodies, and autoantibodies to extractable nuclear antigens and double-stranded DNA. Serum levels of apolipoproteins A and B, C3, C4, and C-reactive protein were measured, as well as serum levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-10. Lupus activity was scored according to the Systemic Lupus Erythematosus Disease Activity Index 2000. Sixty-nine patients (73.4%) had dyslipidemia, and the remaining 25 patients (26.6%) were non-dyslipidemic. Lupus activity was correlated with non-high-density lipoprotein cholesterol and triglyceride (TG) levels (non-HDL-C, r?=?0.34 and p?=?0.0043 and r?=?0.46 and p?<?0.0001, respectively). Atherogenic indexes apolipoprotein B/apolipoprotein A and TG:HDL-C ratios were higher in dyslipidemic women, and TG:HDL was correlated with disease activity (r?=?0.40, p?=?0.0007). IL-6, TNF-α, and IL-10 levels were similar between groups; however, a positive correlation between IL-6 and CRP levels was only observed in the group with dyslipidemia (r?=?0.55, p?<?0.0001). Female Brazilian SLE patients present a high prevalence of dyslipidemia and exhibit a higher risk of cardiovascular diseases as compared with female SLE patients without dyslipidemia and healthy individuals.     

Analysis of PD-1 and Tim-3 expression on CD4<Superscript>+</Superscript> T cells of patients with rheumatoid arthritis; negative association with DAS28

Expression of T cell immunoglobulin and mucin-domain containing-3 (Tim-3) and programmed cell death-1 (PD-1) was studied on CD4⁺ T cells of patients with rheumatoid arthritis (RA). Association of Tim-3 and PD-1 expression with disease activity of RA patients was also addressed. A total of 37 RA patients and 31 sex- and age-matched healthy controls were included in this study. Disease activity of RA patients was determined by Disease Activity Score of 28 joints scoring system (DAS28). A three-color flow cytometry method was applied to determine the frequency of Tim-3⁺/PD-1⁺/CD4⁺ T cells. To measure the cytokine production, peripheral blood mononuclear cells (PBMCs) were stimulated with PMA/ionomycin. Concentrations of IL-17, IL-10, IFN-γ, and TNF-α were measured in culture supernatants by ELISA. The frequency of PD-1⁺/CD4⁺ and Tim-3⁺/PD-1⁺/CD4⁺ T cells was significantly higher in patients with RA compared to that in controls (p?=?0.0013 and p?=?0.050, respectively). The percentage of Tim-3⁺/CD4⁺ T cells was similar in patients and controls (p?=?0.4498). The RA patients have produced significant higher levels of TNF-α, IL-17, and IFN-γ than those of healthy controls (p?=?0.0121, p?=?0.0417, and p?=?0.0478, respectively). Interestingly, an inverse correlation was found between the frequency of Tim-3⁺/CD4⁺ cells and DAS28 of RA patients (r?=???0.4696, p?=?0.0493). Similarly, the percentage of Tim-3⁺/PD-1⁺/CD4⁺ T cells was also revealed an inverse correlation with DAS28 (r?=???0.5268, p?=?0.0493). Moreover, significant positive correlations were detected between the concentrations of TNF-α (r?=?0.6418, p?=?0.0023) and IL-17 (r?=?0.4683, p?=?0.0373) with disease activity of RA patients. Our results indicate that Tim-3 and PD-1 are involved in immune dysregulation mechanisms of rheumatoid arthritis and could be considered as useful biomarkers for determination of disease activity and progression.     

HDL does not influence the polarization of human monocytes toward an alternative phenotype

Background

Macrophages are crucial cells in the pathogenesis of atherosclerosis. Macrophages are plastic cells which can switch from a classical pro-inflammatory M1 to an alternative anti-inflammatory M2 macrophage phenotype, depending on the environmental stimuli. Because high-density lipoprotein (HDL) cholesterol levels are inversely correlated to cardiovascular disease and since HDL displays anti-inflammatory properties, we investigated whether HDL can affect alternative macrophage differentiation of primary human monocytes in the presence of interleukin (IL)-4, a M2 macrophage polarization driver, in vitro and ex vivo.

Methods and results

M2 macrophages are highly responsive to HDL stimulation, since the expression of pentraxin 3 (PTX3), a well known HDL target gene, is induced by HDL more strongly in M2 macrophages than in control unpolarized resting macrophages (RM). As expected, the expression of M2 markers, such as Mannose Receptor (MR), CD200 Receptor (CD200R), Coagulation factor XIII A1 (F13A1), IL-1 receptor antagonist (IL-1RA) and IL10, was induced in IL-4 polarized M2 macrophages compared to RM. However, incubation with HDL added in vitro did not modulate the gene expression of M2 macrophage polarization markers. Moreover, monocytes isolated from subjects with genetically low HDL levels, carrying ABCA1 or LCAT mutations, differentiated ex vivo into M2 macrophages without any difference in the alternative macrophage marker expression profile.

Conclusions

These in vitro and ex vivo results indicate that, contrary to mouse macrophages, HDL does not influence macrophage M2 polarization of human monocyte-derived macrophages. Thus, the anti-inflammatory properties of HDL in humans are probably not related to the enhancement of the M2 macrophage phenotype.     

<Emphasis Type="Italic">C-reactive protein</Emphasis> +1444CT (rs1130864) genetic polymorphism is associated with the susceptibility to systemic lupus erythematosus and C-reactive protein levels

The T rare allele of +1444CT (rs1130864) polymorphism of C-reactive protein (CRP) has been associated with increased CRP levels in some inflammatory conditions, but its role on systemic lupus erythematosus (SLE) susceptibility and on CRP levels in SLE patients remains uncertain. The objective of the study was to evaluate the association between the rs1130864 CRP polymorphism with SLE susceptibility, disease activity, and CRP levels in SLE Brazilian patients. The study enrolled 176 SLE patients and 137 controls. SLE disease activity was assessed using the SLE Disease Activity Index (SLEDAI). The rs1130864 CRP polymorphism was determined using polymerase chain reaction and restriction fragment length polymorphism. SLE patients presented higher body mass index (p = 0.046) and CRP levels (p = 0.017) than controls. The genotype and allele frequencies of patients differed from controls [CC vs. CT = odds ratio (OR) 1.730, 95% confidence interval (CI) 1.068–2.803, p = 0.035; CC vs. TT = OR 3.667, 95% CI 1.410–9.533, p = 0.009; C vs. T = OR 1.883, 95% CI 1.299–2.728, p = 0.001)]. Patients carrying the T allele presented higher CRP levels (p = 0.009), were more frequent Caucasians (p = 0.018), and with no use of immunosuppressive treatment (p = 0.004) than those carrying the C allele. However, the SLEDAI and anti-double-stranded DNA positivity did not differ from those carrying T vs. C allele (p = 0.595 and p = 0.243, respectively). The rs1130864 CRP polymorphism was associated with SLE susceptibility and CRP levels, but not with disease activity, suggesting that this polymorphism may play a role in the pathophysiology of SLE through increasing the CRP that, probably, plays an inflammatory role in SLE pathophysiology.     

Influence of <Emphasis Type="Italic">MX1</Emphasis> promoter rs2071430 G/T polymorphism on susceptibility to systemic lupus erythematosus

The expression of interferon inducible genes are reported to be heightened in systemic lupus erythematosus (SLE); nevertheless, not much is known regarding the genetic variants underlying these genes and their role in the pathogenesis of disease. Herein, we aim to explore the potential association and contribution of polymorphisms in MX1 gene (i) promoter with part of exon 1 (ii) intron 6, and (iii) their resulting haplotypes, with susceptibility to SLE. A total of 306 subjects, 152 SLE and 154 healthy controls (HC), were screened by direct sequencing method. Statistical analysis was carried out using appropriate software. The screening region of interest in MX1 revealed the existence of promoter (?123C/A, ?88G/T, ?20 A/C) and intron 6 (+9862G/A, +10190G/A, +9901C/G, +9920C/A, +9959C/T, +10047A/G) variants in SLE and HC. A significant association was observed between MX1 ?88G/T SNP and susceptibility to SLE (χ ²?=?4.18, p?=?0.04, OR?=?1.89, 95 % CI 1.03–3.5). Haplotype analysis also revealed increased risk of SLE among individuals carrying CTA haplotype (?123 C, ?88 T, ?20 A) (χ ²?=?5.74, p?=?0.017, OR?=?4.28, 95 % CI 1.30–14.06). None of the other tested variants showed any significant association with SLE. The present study is the first to reveal the influence of genetic variation in MX1 gene in susceptibility to SLE.     

Gastrointestinal system manifestations in juvenile systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease which may involve gastrointestinal system (GIS). The aim of this study was to present GIS manifestations of pediatric SLE patients. The medical files of 69 children with SLE followed between January 2011 and January 2016 were reviewed. All fulfilled the Systemic Lupus International Collaborating Clinics criteria. All patients (≤18 years of age) with GIS manifestations were included. GIS manifestations were observed in 19 (27.5%) out of 69 SLE patients and present at the time of SLE diagnosis in 13 (68.4%). The GIS manifestations due to SLE were autoimmune hepatitis (AIH) (n = 8) and lupus enteritis (n = 1). Manifestations associated with SLE were hepatomegaly and hypertransaminasemia due to macrophage activation syndrome (MAS) (n = 3) and hepatic steatosis (n = 1). GIS manifestations as a result of the adverse events of drugs were as follows: toxic hepatitis (n = 3; associated with methotrexate and nonsteroidal anti-inflammatory drugs in one, methotrexate in another, and azathioprine in another patient), azathioprine-induced cholestatic hepatitis (n = 1), and gastritis associated with corticosteroid (n = 1). In one patient, acute appendicitis occurred as a coincidence. In this study, one of every five pediatric SLE patients had GIS-related manifestations. GIS involvement may occur as an initial manifestation of the disease.     

巨噬细胞在支气管哮喘中的作用及研究进展

受微环境变化的影响,巨噬细胞分为经典激活的巨噬细胞(M1)和非经典激活的巨噬细胞(M2).M1型巨噬细胞可释放如肿瘤坏死因子α(TNF-α)和IL-1β等促炎因子加重炎症反应,也可因极化的增多发挥抗炎作用.M2型巨噬细胞分为M2a、M2b和M2c 3种亚型,M2a及M2b型巨噬细胞主要产生炎性细胞因子如ID4和IL-13,M2c型巨噬细胞主要产生抗炎细胞因子如IL-10并有很强的吞噬功能.细胞因子、趋化因子和免疫调节细胞影响着M1型和M2型巨噬细胞的平衡.巨噬细胞不同的极化在支气管哮喘发生与发展中起到重要的作用.     

Patients with primary breast and primary female genital tract diffuse large B cell lymphoma have a high frequency of <Emphasis Type="Italic">MYD88</Emphasis> and <Emphasis Type="Italic">CD79B</Emphasis> mutations

This study is to retrospectively evaluate the prevalence of MYD88 and CD79B mutations and the clinicopathologic characteristics of patients with primary diffuse large B cell lymphoma (DLBCL) of the female genital tract and breast. The characteristics, treatments, and outcomes of 19 patients diagnosed with primary DLBCL of the female genital tract and breast, who had formalin-fixed and paraffin-embedded tissues obtained from diagnostic samples diagnosed between January 2004 and June 2016, were analyzed retrospectively. Nineteen female patients (7 with primary breast and 12 with primary female genital tract DLBCL) were included in this retrospective study. Eleven patients (57.9%) carried a MYD88 mutation, including 10 with MYD8 L265P and 1 with the MYD88 L265S mutation. Seven patients (36.8%) harbored a CD79B mutation, which included two cases with CD79B Y196H, two cases with CD79B Y196N, one case with CD79B Y196D, one case with CD79B Y196F, and one case with CD79B Y196X. Four cases had both MYD88 and CD79B mutations. The clinicopathologic parameters, progression-free survival (PFS), and overall survival (OS) of the MYD88 mutation-carrying group were not significantly different from those of the MYD88 wild-type group except for higher LDH levels. Six patients received cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP), while 13 patients received rituximab plus CHOP, and 13 patients received central nervous system prophylaxis. The median OS and PFS were 73 and 56 months, respectively. Patients with primary breast and primary female genital tract DLBCL have a high frequency of MYD88 and CD79B mutations. The presence of these mutations does not affect survival but may offer additional therapeutic options.     

<Emphasis Type="Italic">Fusobacterium nucleatum</Emphasis> Potentiates Intestinal Tumorigenesis in Mice via a Toll-Like Receptor 4/p21-Activated Kinase 1 Cascade

Background

The underlying pathogenic mechanism of Fusobacterium nucleatum in the carcinogenesis of colorectal cancer has been poorly understood.

Methods

Using C57BL/6-Apc^Min/+ mice, we investigated gut microbial structures with F. nucleatum, antibiotics, and Toll-like receptor 4 (TLR4) antagonist TAK-242 treatment. In addition, we measured intestinal tumor formation and the expression of TLR4, p21-activated kinase 1 (PAK1), phosphorylated-PAK1 (p-PAK1), phosphorylated-β-catenin S675 (p-β-catenin S675), and cyclin D1 in mice with different treatments.

Results

Fusobacterium nucleatum and antibiotics treatment altered gut microbial structures in mice. In addition, F. nucleatum invaded into the intestinal mucosa in large amounts but were less abundant in the feces of F. nucleatum-fed mice. The average number and size of intestinal tumors in F. nucleatum groups was significantly increased compared to control groups in Apc^Min/+ mice (P?<?0.05). The expression of TLR4, PAK1, p-PAK1, p-β-catenin S675, and cyclin D1 was significantly increased in F. nucleatum groups compared to the control groups (P?<?0.05). Moreover, TAK-242 significantly decreased the average number and size of intestinal tumors compared to F. nucleatum groups (P?<?0.05). The expression of p-PAK1, p-β-catenin S675, and cyclin D1 was also significantly decreased in the TAK-242-treated group compared to F. nucleatum groups (P?<?0.05).

Conclusions

Fusobacterium nucleatum potentiates intestinal tumorigenesis in Apc^Min/+ mice via a TLR4/p-PAK1/p-β-catenin S675 cascade. Fusobacterium nucleatum-induced intestinal tumorigenesis can be inhibited by TAK-242, implicating TLR4 as a potential target for the prevention and therapy of F. nucleatum-related colorectal cancer.

     

Changes and clinical significance of CD8+CD122+ T cells in the peripheral blood of patients with ankylosing spondylitis

The aim of our study was to explore the relationship between circulating T cells and ankylosing spondylitis (AS) and to find the role of the CD8+CD122+ T cells in the pathogenesis and progression of AS. With the method of case-control design, flow cytometry was performed to quantitatively determine the percentage of circulating CD8⁺CD122⁺ T cells in peripheral blood mononuclear cells from established AS patients and age- and gender-matched healthy controls. Serum levels of inflammatory cytokines like interleukin-2, interleukin-10, interleukin-15, TGF-β1, and TNF-ɑ were detected by enzyme-linked immunosorbent assay. The t test was used to compare differences between groups, correlation analysis with Spearman rank test and Pearson correlation was performed. The percentage of circulating CD8⁺CD122⁺ T cells were significantly increased in AS patients compared with controls (Z = ? 4.917, P = 0.001). Plasma IL-2, IL-10, IL-15, TGF-β1, and TNF-ɑ levels between cases and controls were analyzed but no statistically significant differences were found. The percentage of circulating CD8⁺CD122⁺ T cells were not significantly different in the two groups of patients with AS whether they were treated or not. In addition, the percentage of circulating CD8⁺CD122⁺ T cells was positively correlated with disease duration, CRP, and ASDAS-CRP. The CD8⁺CD122⁺ T cells in the peripheral blood of AS patients may be involved in the development of AS, and they may coordinate regulate inflammation and immune dysregulation in patients with AS, which may play an important role in the pathogenesis and prognosis of AS.     

Polymorphisms of genes encoding interleukin-4 and its receptor in Iranian patients with juvenile idiopathic arthritis

As cytokines, including interleukin-4 (IL-4), seem to have a pivotal role in the pathogenesis of juvenile idiopathic arthritis (JIA), this study is aimed at investigating of association of polymorphisms in IL-4 and IL-4 receptor α (IL-4RA) genes with susceptibility to JIA. A case-control study was conducted on 53 patients with JIA and 139 healthy unrelated controls. Single nucleotide polymorphisms of IL-4 gene at positions -1098, -590, and -33, as well as IL-4RA gene at position +1902 were genotyped using polymerase chain reaction with sequence-specific primers method and compared between patients and healthy individuals. At the allelic level, C allele at IL-4 -33 was found to be more frequent in patients compared to control (P value <0.01). At the genotypic level, CC genotype at IL-4 -590 (P value <0.01), together with CC and TT genotypes at IL-4 -33 (P value <0.01), were significantly higher in patients with JIA, while TC genotypes at IL-4 -590 and -33 positions were found to be lower in case group (P value <0.01). At the haplotypic level, IL-4 (positions -1098, -509, -33) TTC, GCC, and TTT haplotypes were significantly lower than controls (P value <0.01, P value?=?0.03, and P value?=?0.04, respectively). Although, TCC haplotype at the same positions was found to be higher in patients (P value <0.01). Polymorphic site of +1902 IL-4RA gene did not differ between cases and controls. Polymorphisms in promoter region of IL-4 but not IL-4RA genes confer susceptibility to JIA and may predispose individuals to adaptive immune responses.     

Higher activation of the interferon-gamma signaling pathway in systemic lupus erythematosus patients with a high type I IFN score: relation to disease activity

Increased IFN-γ levels have been associated with systemic lupus erythematosus (SLE). However, the relationships among IFN-γ, type I interferons (IFNs) and clinical features have not been extensively studied. Peripheral blood samples from 44 SLE patients and 36 healthy donors (HDs) were collected. Quantitative real-time PCR was used to assess the mRNA expression of IFNG, type II IFN-inducible genes (IRF1, GBP1, CXCL9, CXCL10, and SERPING1, which are used for the type II IFN score), type I IFN-inducible genes (IRF7, MX1, ISG15, and ISG20, which are used for the type I IFN score), TBX21, and EOMES in peripheral blood mononuclear cells. Flow cytometry was used to measure the IFN-γ levels in lymphocytes. The mRNA levels of type II IFN-inducible genes, IFNG, TBX21, and EOMES were significantly higher in SLE patients than those in HDs. Similarly, the percentages of IFN-γ-producing cells in lymphocytes and their subsets in SLE patients were significantly increased. Linear regression indicated that IFNG expression levels and type II IFN scores were positively correlated with anti-double-stranded DNA autoantibody levels and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores. Compared with patients with low type I IFN scores, patients with high type I IFN scores showed increased type II IFN scores and SLEDAI scores. Type II IFN scores were positively associated with type I IFN scores. The IFN-γ signaling pathway is activated in SLE patients and may be considered an index of disease activity. IFN-γ, together with type I IFNs, promotes the pathogenesis of SLE.     

Monocyte-derived macrophage cytokine responses induced by M. bovis BCG.

SETTING: One important aspect of macrophage function is the production of inflammatory and anti-inflammatory cytokines, which in turn affect the survival of intracellular organisms such as mycobacteria. OBJECTIVE: To determine the relationship between phagocytosis of mycobacteria and expression of intracellular cytokines. DESIGN: Phagocytosis and cytokine production were studied simultaneously within human monocyte-derived macrophages (MDMs) from healthy donors using fluorescent labelling of M. bovis BCG and flow cytometry. RESULTS: At a range of infection ratios (5:1, 1:1, 0.2:1) TNF- alpha, IL-10, IL-6 and IL-12 were all produced in a dose-dependent manner. At an infection ratio representative of the in vivo situation (1:1), cytokine production was induced in both MDMs containing intracellular M. bovis BCG and in uninfected bystander MDMs. Phagocytosis increased over time, but there was considerable donor variation: the proportions of cells containing one or more mycobacterium were 15.4+/-14.8% (mean+/-SD) at 4 h and 32.7+/-21.1% at 24 h (n=19). Analysis of cytokine production by MDMs not containing mycobacteria (bystander cells) at 4 h revealed that these uninfected cells produced 79+/-6.6% of the TNF- alpha, 53.9+/-40.0% of the IL-10 and 64.2+/-12.4% of the IL-12. By 20 h these proportions had decreased to 57+/-13.5%, 30.9+/-7.4% and 45.5+/-13.3% respectively. CONCLUSION: Both infected and bystander MDMs can be stimulated to produce cytokines in response to M. bovis BCG, indicating that the ability of MDMs to produce cytokines is not necessarily dependent on the ability to phagocytose mycobacteria.     

Association between paraoxonase-1 gene Q192R and L55M polymorphisms in systemic lupus erythematosus (SLE) and anti-phospholipid syndrome (APS) in a population from Cairo of Egypt

Paraoxonase-1 (PON1) is involved in the oxidative stress process that cause tissue damage observed in systemic lupus erythematosus (SLE) and anti-phospholipid syndrome (APS). The aim of the present study was to investigate the association of PON1 Q192R and L55M polymorphisms with risk of SLE and associated APS among Egyptian sample. The study included 120 SLE patients (45 without APS and 75 with APS) and 120 healthy subjects. PON1 Q192R and L55M polymorphisms were genotyped by real-time PCR. No significant differences in Q192R genotypes or allele frequencies were found between patients and controls (p = 0.5 and 0.1, respectively). The frequency of the 55M allele was significantly higher in SLE patients than in controls (66.6 vs. 43.3%), while the 55L allele was more frequent in controls (56.6%) than in patients (33.3%) (p = 0.03). The LL genotype was more frequent in controls (21.6%) than in patients (10%) while M allele carrier genotypes (LM + MM) were more frequent among patients (90%) than controls (78.3%), p = 0.04. Also, the 55M allele was more frequent in APS patients (73.3%) than in patients without APS (55.6%), p = 0.004. M allele carrier genotypes (LM + MM) was significantly higher among APS patients (95.4%) than in non-APS patients (80%), p = 0.008. Our results indicated that the PON1 L55M polymorphism associated with SLE and associated APS in a population from Cairo of Egypt, while the Q192R polymorphism plays no role in disease susceptibility. A large scale study to assess PON1 polymorphisms, PON1 activity, and markers of oxidative stress interaction is needed to clarify the role of PON-1 polymorphisms in the pathogenesis of SLE and associated APS.