Spaska Stanilova

Comparative study of circulating immune complexes quantity detection by three assays : CIF-ELISA, C1Q-ELISA and anti-C3 ELISA

The assessment of the soluble immune complexes (IC) in human sera is traditionally performed by the C1q binding assay. In the present study, a novel method for the quantity of immune complexes was reported. The methodology was based on measuring their deposition on solid-phase C3 binding glycoprotein (CIF), using an enzyme-linked immunosorbent assay. We also used ELISA that employed anti-C3 antibodies to determined the quantity of immune complexes. The three assays were evaluated for their performance characteristics on the same specially prepared samples: 55 normal sera, 99 sera from RA, 88 sera from SLE, and 27 sera from PSS. The results were compared by reference to a common standard-heat aggregated IgG that possesses many activities of immune complexes. Three of the tests used displayed almost the same specificity (over 95%), while their relative sensitivity varied depending on the disease sera tested. The sensitivity of the assays used was recorded highest for C1q ELISA-28.97% of positive sera, followed by CIF-ELISA-19.63% and lowest for anti-C3 ELISA-17.29%. A well-expressed correlation was found between CIF-ELISA and anti-C3 ELISA data (r=0.42), and a week correlation was noted when comparing CIF-ELISA and C1q ELISA IC levels detected (r=0.28). When the correlation coefficients were calculated individually for each disease category, they were clearly different, and that reflected indirectly in different sensitivities of the test for various disease categories. We also found that the results from the simultaneous performance of the tests demonstrated low percentage positive results when three or two assays were used. This is most probably due to the different assay abilities to detect IC with different sizes and composition, which shows that a small part of IC in the tested sera can be detected simultaneously by more than one assay. On the basis of the results obtained, we concluded that optimal screening for IC could be achieved by parallel application of several different methods.

The combined effect of interleukin (IL)-10 and IL-12 polymorphisms on induced cytokine production

Interleukin (IL)-12 and IL-10 are immunoregulatory cytokines with an antagonistic effect of the T-helper (Th)1/Th2 cytokine balance and provide a functional link between innate and adaptive immune responses. The aim of the study was to investigate the combined effect of -1082A*G in IL10 and +16974A*C in IL12B single nucleotide polymorphisms (SNPs) on induced cytokine production by stimulated peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. The presence of the high-producer IL-12p40 genotype led to diminished production of IL-10 as determined by the -1082*G allele of SNP in IL10. Significantly decreased IL-10 production was detected in AA+AG/GG in comparison with the low-producer IL-12p40 (AC/CC+AG/GG) genotype combination after stimulation with C3bgp (2+/-4 vs. 29+/-14.2 pg/ml; p=0.0003) and LPS (33.4+/-13.5 vs. 93.3+/-59.6 pg/ml; p=0.019). IL-12p40 production was independent of IL10 genotype. The present results demonstrated that the production of IL-10 from PBMC depended on both -1082A*G in IL10 and +16974A*C in IL12B polymorphisms.

Association of Polymorphisms in Regulatory Regions of Interleukin-12p40 Gene and Cytokine Serum Level with Colorectal Cancer

ABSTRACT The present study investigates the association between IL12Bpro and +16974A/C in 3′ -untranslated region (UTR) polymorphisms of IL12B and IL-12p40 serum level related to development of colorectal cancer (CRC). Our results showed similar distribution of both the investigated polymorphisms among CRC patients and healthy donors, which suggests that these polymorphisms in IL12B were not associated with the development of CRC. However, we found an increased IL-12p40 level in sera from patients compared to healthy donors and the highest level was observed in stage I compared to more advanced stages of CRC. These findings demonstrated that IL-12p40 serum level has an association with the progression of CRC.

Ile105Val GSTP1 polymorphism and susceptibility to colorectal carcinoma in Bulgarian population.

Background and aimsEtiologically, the sporadic colorectal cancer (CRC) is a complex and multifactorial disease that is linked to both exogenic and endogenic factors. Accumulating evidence indicates that susceptibility to cancers, including CRC, is mediated by genetically determined differences in the effectiveness of detoxification of potential carcinogens. A member of the glutathione-S-transferase (GST) family, GSTP1, is an important candidate for involvement in susceptibility to carcinogen-associated CRC. An A→G transition in exon 5 of the GSTP1 gene resulting in Ile105Val amino acid substitution has been identified. This change leads to alteration in catalytic efficiency of variant enzyme. The aim of the current study was to evaluate the influence of Ile105Val GSTP1 polymorphism on susceptibility to CRC.Materials and methodsThe GSTP1 genotyping was conducted in a case-control study of 80 ethnic Bulgarian CRC patients and 126 unaffected controls using polymerase chain reaction restriction fragment length polymorphism method.ResultsA statistically significant case-control difference in genotype frequencies was observed: 0.69 vs 0.54 for Ile/Ile, 0.22 vs 0.39 for Ile/Val, and 0.09 vs 0.07 for Val/Val (p = 0.049). The odds ratio (OR) for Val/Val was close to 1 (0.96, 95%CI: 0.35–2.66, p = 0.942), whereas the OR for Ile/Val was significantly lower, 0.45 (95%CI: 0.24–0.86, p = 0.016), compared to the referent Ile/Ile genotype. Although a prevalence of the GSTP1 variant allele-containing genotypes (Ile/Val or Val/Val) was found in controls than in patients (OR = 0.53, 95%CI: 0.30–0.96, p = 0.035), the allele frequencies did not show significant difference between cases and controls (p = 0.127).ConclusionsBased on the obtained protective effect of Ile/Val GSTP1 genotype, we could suggest that Ile105Val GSTP1 polymorphism may play some role in susceptibility to CRC.

The inhibition of JNK and p38 MAPKs downregulates IL-10 and differentially affects c-Jun gene expression in human monocytes

Interleukin-10 is the most important anti-inflammatory cytokine that controls the progress of the immune response. The molecular mechanisms driving the IL10 gene regulation are not well understood. To gain insight into this process we studied the IL-10 expression on mRNA and protein levels, together with c-Jun, FOXP3 and RelA transcription factors gene expression in human monocytes. We investigated also, the involvement of JNK and p38 transduction pathways in IL-10, c-Jun, FOXP3 and RelA gene expression. The quantity determination of IL-10 was performed by ELISA. qRT-PCR was performed for the detection of mRNA transcripts. The pharmacological inhibitors SP600125 and SB202190 were used to explore JNK and p38 MAPKs involvement in IL10, c-Jun, FOXP3 and RelA gene expression. The measurement of IL-10 mRNA synthesis, triggered by lipopolysaccharide (LPS) or C3 binding glycoprotein (C3bgp) showed that stimulation with both inducers led to similar high level of IL-10 mRNA synthesis, whereas C3bgp was the stronger inducer of IL-10 production than LPS. JNK and p38 inhibition significantly decreased IL-10 expression in stimulated cells. C3bgp and LPS induced comparatively low expression of FOXP3, RelA and c-Jun mRNA in monocytes. The inhibition of p38 MAPK in stimulated monocytes resulted in significant enhancement of c-Jun mRNA synthesis suggesting the functional relation between p38 MAPK and c-Jun gene expression. We concluded that the IL10 gene transcription did not associate with enhancement of c-Jun, RelA and FOXP3 gene expression and strictly depended on the JNK and p38 MAPKs activation in stimulated human monocytes.

Advanced Colorectal Cancer Is Associated With Enhanced Il-23 and IL-10 Serum Levels

Objective: Cytokines play a pivotal role in the induction of host immune responses against tumor growth and are involved in the development and progression of colorectal cancer in humans. Methods: A group of 48 patients and 27 healthy volunteers were included in the study. The quantitative determination of IL-23, IL-17, IL-10, and IFN-a serum levels were performed by ELISA. Results: We observed significantly enhanced IL-23 in CRC patients compared to the controls. The serum level of IL-10 was significantly higher in CRC patients than healthy donors. The highest level of IL-10 was detected in patients with stage IV, which was significantly greater than those in stages I, II, and III. Conclusions: We found that IL-23 and IL-10 levels were significantly elevated in patients’ sera, in contrast to IL-17 and IFN-a, and this serum cytokine profile may play a role in tumor development. In addition, an increased level of IL-10 was strongly associated with the progression of colorectal carcinoma (CRC).

High expression of Foxp3, IL-23p19 and survivin mRNA in colorectal carcinoma

IntroductionCytokines have been suggested to both modulate anti-tumor responses and promote tumor growth.Materials and methodsWe analyzed the expression of pro-inflammatory IL-12p35, IL-12p40, IL-23p19, anti-inflammatory IL-10, antiapoptotic factor survivin, and transcription factors—RelA, c-Jun, and Foxp3 mRNA in patients’ blood, colon carcinoma tissue, and in normal mucosal tissue by real-time polymerase chain reaction. The quantity determination of serum IL-12p40, IL-23, and IL-10 was performed by enzyme-linked immunosorbent assay.ResultsWe observed significantly higher levels in patients for all three analyzed cytokines, with IL-23 concentration change being the highest. We detected the greatest upregulation of IL-23p19, Foxp3 and survivin mRNA in colorectal carcinomas than normal mucosa. A statistically significant upregulation of IL-12p40, IL-10, and c-Jun mRNA but not for IL-12p35 and RelA mRNA in tumor tissue comparing to normal tissue was also established.ConclusionsIn conclusion, we show a characteristic gene expression profile combining markers associated with inhibition of anti-tumor immune response (Foxp3, IL-10), inhibition of apoptosis (survivin), and induction of the cytokines with protumoral activity as IL-12p40 and IL-23p19 (IL-23) in the colorectal tumor tissue but not in peripheral blood of patients.

Preliminary studies on the immunomodulatory effect of the C3 binding glycoprotein isolated from Cuscuta europea.

This study investigates the immunomodulatory effect of a C3 binding glycoprotein (C3bgp), isolated from the parasitic plant Cuscuta europea. When BALB/c mice, immunized with sheep red blood cells (SRBC), were given a single intraperitoneal injection of C3bgp a dose-dependent immunostimulation was observed. The stimulation was assessed by an increase in the number of haemolytic plaque forming cells (PFC) and haemaglutination titres. The induction was time dependent in respect to the administration of both the C3bgp and SRBC. When C3bgp was applied 24 h before SRBC at a dose of 30 microg per mouse (1.2 mg/kg), a well expressed immunostimulation was found. It was also found that giving C3bgp to mice, which had previously been treated with the immunosuppressive drug cyclophosphamide (CY), produced an increase in PFC. The immune response was also restored in vitro experiments were performed using human whole blood cultures stimulated with 30 microg/ml C3bgp in the presence or absence of egg albumin (OVA) as antigen for 72 to 168 h. In C3bgp stimulated cultures it was found that after 120 h there was a high expression of the CD 19+ subset of the activation antigen CD25 (IL-2R) as assessed by flow cytometric phenotype analysis. Supernatants from cultures with different stimuli were assayed by a solid phase ELISA for the determination of OVA-specific IgM at 120, 144 and 168 h. It was found that C3bgp application alone, failed to enhance OVA specific IgM, but significantly high levels of IgM in cultures containing C3bgp and OVA, were detected. Overall it has been shown that the C3 binding glycoprotein, as obtained from the parasitic plant Cuscuta europea, has strong immunostimulatory properties both in vivo and in vitro.

Induction of immunostimulatory cytokine genes expression in human PBMCs by a novel semiquinone glucoside derivative (SQGD) isolated from a Bacillus sp. INM-1.

In the present study, a semiquinone glucoside derivative (SQGD) isolated from a radioresistant bacterium Bacillus sp. INM-1 was evaluated for its immunostimulatory activities. Human peripheral blood mononuclear cells (PBMCs) were stimulated by different doses (30-90 microg/ml) of SQGD for different time (3-12h) intervals at 37°C, and IL-12p40, IL-23p19, IL-10, RelA and c-Jun gene expression analysis was carried out by qRT-PCR method. SQGD dose dependent cytokines protein expression kinetic analysis was carried out using western blotting. As the results of SQGD (30μg/ml) stimulation for 3h at 37°C, significant induction in IL-12p40, IL-23p19 and RelA gene expression was observed in PBMCs compared to unstimulated control cells. However, no such induction in IL-10 and c-Jun gene expression was observed. Time dependent protein expression study indicated significant increase in IL-12p40, IL-12p35, IL-23p19 and RelA protein expression at 3-6h, which was found decrease at 12h upon SQGD treatment. In contrast, IL-10 protein expression was found to enhance significantly at 12h after SQGD treatment to the PBMCs. SQGD dose dependent study showed approximately similar level of induction in IL-12p40, IL-12p35, IL-23p19 and RelA proteins expression at all tested concentration (30-90 microg/ml) compared to control. However, no significant change in the IL-10 and c-Jun protein expression was observed at any SQGD concentration. SQGD treatment (0.25mg/kgbwt.) was also found to enhance anti-keyhole Limpet Hemocynin (KLH) IgM antibodies significantly in the mice immunized by KLH. Thus, SQGD fraction stimulates cellular immunity by inducing immunostimulatory cytokines and humoral immunity by enhancing IgM antibodies and could be a promising immunostimulant. Further studies related to molecular mechanisms offering immunostimulation is underway, will certainly helpful to unravel its mode of action in the biological system.

Association of single nucleotide polymorphism at position −308 of the tumor necrosis factor-alpha gene with ankylosing spondylitis and rheumatoid arthritis

In this study, we analyzed the putative association between the −308 G/A polymorphism in the promoter region of the tumor necrosis factor (TNF) α gene (rs1800629) and chronic inflammatory arthritis in the Bulgarian population. A case-control study was carried out on 58 patients with ankylosing spondylitis (AS), 108 rheumatoid arthritis (RA) patients and 177 healthy subjects. −308 G/A TNF-α genotypes of patients and controls were determined by restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR). No significant association between the rs1800629 polymorphism and RA risk in the study cohort was observed. However, there were significant differences in the genotype and allele frequencies of the −308 G/A TNF-α polymorphism between AS patients and the healthy subjects. In logistic regression analysis, the presence of the TNF-α −308A allele in the genotype (AA + AG vs. GG) was associated with a 3.298 times lower risk of developing AS. In addition, in AS, there were associations for age at disease onset (<29 years; odds ratio (OR) = 0.222), disease severity (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score > 4; OR = 0.152) and response to anti-TNF treatment (OR = 2.25) under a dominant model (AA + AG vs. GG). In conclusion, our results suggested that the promoter polymorphism −308 G/A in the TNF-α gene had no significant effect on RA development, but could play a role in AS development and in determining the age of disease onset, disease severity and therapeutic outcome of AS in the Bulgarian patients who participated in our study.