No gender differences in the 24-month course of non-invasive liver fibrosis markers after DAA therapy in HCV-mono and HCV/HIV-coinfected patients

Untreated HCV mono and HCV/HIV coinfected women have lower degrees of liver fibrosis (LF) compared to men. Direct acting antiviral (DAA) therapy attains viral eradication in > 90% of patients with progressive LF decline in parallel. Gender-related differences in LF regression in the long term assessed by non-invasive liver fibrosis markers (NILFM) in HCV mono and HCV/HIV coinfected after DAA treatment have not been explored so far. 374 HCV-infected adult patients, 214 of them HCV/HIV coinfected, were followed-up for 24 months after starting DAA therapy. LF was assessed by NILFM: transient elastometry (TE) and several biochemical indexes (APRI, Forns, FIB-4). Men had significantly more advanced LF at baseline than women assessed by NILFM. No LF differences at baseline in age, HIV coinfection course (CD4, HIV viral load), and HCV features (HCV viral load, genotype) were detected. No significant gender differences in LF decline after comparing 24-month and baseline LF values were observed. LF changes after DAA therapy were similar in HCV mono and HCV/HIV coinfected patients and in both sexes. Gender did not influence the course of LF decline after DAA assessed by NILFM: TE (P = 0.8), APRI (P = 0.9), Forns (P = 0.4) and FIB-4 (P = 0.7) by multivariate analysis. No gender differences in the 24 month LF decline after DAA with independence of having HCV mono or HCV/HIV coinfection were found.

205. IL-1 β gene (+3954C/T, exon 5, rs1143634) and NOS2 (exon 22) polymorphisms associate with early aseptic loosening of hip and knee arthroplasties but not with implants infection

Background

Aseptic prosthetic loosening (APL) and prosthetic joint infections (PJI) are frequent complications of hip and knee implants. Polymorphisms of cytokines and nitric oxide (NO), key inflammatory molecules in APL and PJI pathogenesis, could explain individual susceptibility to these complications.

Methods

Three cytokines (IL-1-a, IL-1-β, TNF-α) and two nitric oxide synthase (NOS2, NOS3) genes polymorphisms were genotyped in 77 APL and 117 PJI patients and 145 controls with aseptic hip or knee implants lasting > 16 years. Plasma cytokines and nitrate-nitrite (NOx) levels were measured.

Results

The TT genotype and T allele of the (+3954C/T, exon 5, rs1143634) IL-1β polymorphism were more frequent in APL patients compared to controls (p=0.03 and p=0.02, respectively). No genotypic associations in PJI patients were observed. S. epidermidis was their most frequently isolated microorganism (39.3%). Plasma IL-6, TNF-α and NOx were significantly different between APL and controls (p< 0.0001). Plasma IL-1β and IL-6 were significantly higher in APL T allele carriers vs. non-carriers (p< 0.03). Knee implant (HR 2.488, 95% CI 1.307-4.739, p=0.005), male gender (HR 2.252, 95% CI 1.121-4.525, p=0.023), carriages of the TT genotype of the (+3954C/T) IL-1β polymorphism (HR 3.704, 95% CI 1.274-10.753, p=0.016) and AA genotype of the (exon 22) NOS2 polymorphism (HR 3.509, 95% CI 1.266-9.709, p=0.016) were independently associated with a shorter implant survival by Cox regression.

Conclusion

Genotyping of IL-1β (+3954C/T, exon 5, rs1143634) and NOS2 (exon 22) polymorphisms could be useful as predictors of early hip or knee APL.

Disclosures

All Authors: No reported disclosures.

IL-1 β gene (+3954 C/T, exon 5, rs1143634) and NOS2 (exon 22) polymorphisms associate with early aseptic loosening of arthroplasties

Aseptic prosthetic loosening (APL) and prosthetic joint infections (PJI) are frequent complications of hip and knee implants. Polymorphisms of cytokines and nitric oxide (NO), key inflammatory molecules in APL and PJI pathogenesis, could explain individual susceptibility to these complications. Three cytokines (IL-1-a, IL-1-β, TNF-α) and two nitric oxide synthase (NOS2, NOS3) genes polymorphisms were genotyped in 77 APL and 117 PJI patients and 145 controls with aseptic hip or knee implants that were implanted for > 16 years. Plasma cytokines and nitrate-nitrite (NOx) levels also were measured. The TT genotype and T allele of (+3954 C/T, exon 5, rs1143634) IL-1β polymorphism were more frequent in APL patients compared to controls (P = 0.03 and P = 0.02, respectively). No genotypic associations in PJI patients were observed. Plasma IL-6, TNF-α and NOx were significantly different between APL and controls (P < 0.0001). Plasma IL-1β and IL-6 were significantly higher in APL T allele carriers vs. non-carriers (P < 0.03). Knee implant (HR 2.488, 95% CI 1.307-4.739, P = 0.005), male gender (HR 2.252, 95% CI 1.121-4.525, P = 0.023), carriages of the TT genotype of the (+3954 C/T) IL-1β polymorphism (HR 3.704, 95% CI 1.274-10.753, P = 0.016) and AA genotype of the (exon 22) NOS2 polymorphism (HR 3.509, 95% CI 1.266-9.709, P = 0.016) were independently associated with a shorter implant survival by Cox regression. No genotypic associations in PJI patients were observed. Genotyping of IL-1β (+3954 C/T, exon 5, rs1143634) and NOS2 (exon 22) polymorphisms could be useful as predictors of early hip or knee APL.

The TNF-α (-238 G/A) polymorphism could protect against development of severe sepsis

Primary responses in sepsis-mediated inflammation are regulated by pro-inflammatory cytokines. Variations in the cytokine genes might modify their transcription or expression, plasma cytokines levels and response to sepsis. Activation protein-1 (AP-1) and NF-κB regulate cytokines gene expression in sepsis. A total of 90 severely septic and 91 non-infected patients were prospectively studied. IL-1α (–889 C/T), IL-1β (+3954 C/T), IL-6 (–174 G/C), TNF-α (–238 G/A), TNF-α (–308G/A), IL-8 (–251A/T) and IL-10 (–1082 G/A) SNPs, plasma IL-1β, IL-4, IL-6, IL-8, IL-10, IL-13, IFN-γ, TNF-α and monocyte chemoattractant protein 1 (MCP-1) levels, and AP-1 and NF-κB gene expression by neutrophils were assessed. A allele carriers of TNF-α (–238 G/A) SNP were less frequent among septic patients. IL-6, IL-8, IL-10, TNF-α and MCP-1 levels were higher, and AP-1 and NF-κB gene expressions lower in septic patients. Sepsis was independently associated with higher fibrinogen, neutrophils counts and IL-8 levels, lower prothrombin, absence of the variant A allele of the TNF-α (–238 G/A) SNP, and haemodynamic failure. Death was independently associated with a higher APACHE II score, higher IL-8 levels, and the diagnosis of sepsis. TNF-a (–238 G/A) SNP could protect against sepsis development. Higher IL-8 levels are predictive of sepsis and mortality.

Matrix metalloproteases and their tissue inhibitors in non-alcoholic liver fibrosis of human immunodeficiency virus-infected patients

AIM

To investigate the relationships among diverse metalloproteases (MMPs) and their tissue inhibitors (TIMPs) and non-alcoholic liver fibrosis in human immunodeficiency virus (HIV)-infected patients.

METHODS

Single nucleotide polymorphisms (SNPs) in MMPs, TNF-α and CCR5 genes, and serum levels of MMPs and TIMPs were determined in HIV-infected individuals with/out hepatitis C virus (HCV) coinfection. A total of 158 patients were included, 57 of whom were HCV-coinfected. All patients drank < 50 g ethanol/day. Diverse SNPs (MMP-1 -1607 1G/2G, MMP-8 -799C/T, MMP-9 -1562 C/T, MMP-13 -77A/G, TNF-α -308 G/A, CCR5-∆32), and serum levels of MMPs (2, 3, 8, 9 and 10) and TIMPs (1, 2 and 4) were assessed. Liver fibrosis was determined by transient elastometry, although other non-invasive markers of fibrosis were also considered. Significant liver fibrosis (F ≥ 2) was defined by a transient elastometry value ≥ 7.1 kPa.

RESULTS

A total of 34 patients (21.5%) had liver fibrosis ≥ F2. MMP-2 and TIMP-2 serum levels were higher in patients with liver fibrosis ≥ F2 (P = 0.02 and P = 0.03, respectively) and correlated positively with transient elastometry values (P = 0.02 and P = 0.0009, respectively), whereas MMP-9 values were negatively correlated with transient elastometry measurements (P = 0.01). Multivariate analyses showed that high levels of MMP-2 (OR = 2.397; 95%CI: 1.191-4.827, P = 0.014) were independently associated with liver fibrosis ≥ F2 in the patients as a whole. MMP-2 (OR = 7.179; 95%CI: 1.210-42.581, P = 0.03) and male gender (OR = 10.040; 95%CI: 1.621-62.11, P = 0.013) were also independent predictors of fibrosis ≥ F2 in the HCV-infected subgroup. Likewise, MMP-2, TIMP-2 and MMP-9 were independently associated with transient elastometry values and other non-invasive markers of liver fibrosis. None of the six SNPs evaluated had any significant association with liver fibrosis ≥ F2.

CONCLUSION

Certain MMPs and TIMPs, particularly MMP-2, seems to be associated with non-alcoholic liver fibrosis in HIV-infected patients with/without HCV coinfection.

Factors associated with long-term CD4 cell recovery in HIV-infected patients on successful antiretroviral therapy

OBJECTIVES

The aim of the study was to study the factors associated with immunological recovery in HIV-infected patients with suppressed viral load.

METHODS

Nadir and current CD4 cell counts were recorded in 821 patients, as well as many demographic, epidemiological, lifestyle, clinical, therapeutic, genetic, laboratory, liver fibrosis and viral hepatitis parameters.

RESULTS

The median age of the patients was 44.4 years [interquartile range (IQR) 40.3-48.0 years], the median time since HIV diagnosis was 15.3 years (IQR 10.5-18.9 years), the median time of suppressed viral load was 7.0 years (IQR 4.0-10.0 years) and the median time on the current antiretroviral regimen was 2.8 years (IQR 1.4-4.7 years). The median nadir and current CD4 counts were 193.0 (IQR 84.0-301.0) and 522.0 (IQR 361.0-760) cells/μL, respectively, separated by a median period of 10.2 years (IQR 5.9-12.9 years). The median CD4 count gain during follow-up was 317.0 (IQR 173.0-508.0) cells/μL. Many variables were associated with CD4 cell gains in univariate analyses, including age, gender, epidemiology, prior clinical conditions, fibrosis stage, transient elastometry, aspartate aminotransferase (AST), nadir CD4 count and hepatitis B and C virus infections and genotypes, as well as the durations of follow-up since nadir CD4 count, overall antiretroviral treatment, current antiretroviral regimen, protease inhibitor therapy and suppression of viral load. Multivariate analysis revealed that longer duration of HIV suppression (P < 0.0001), more advanced clinical Centers for Disease Control and Prevention (CDC) stages (P < 0.0001), younger age (P = 0.0003), hepatitis C virus genotypes 1 and 4 (P = 0.003), sexual acquisition of HIV (P = 0.004), and lower transient elastometry values (P = 0.03) were independent predictors of CD4 cell gains. Overall, the model accounted for 14.2% of the variability in CD4 count.

CONCLUSIONS

In addition to the duration of HIV suppression, HIV-related diseases, HIV epidemiology, age, hepatitis C virus genotypes, and liver fibrosis were independently associated with long-term immunological recovery.

The effect of gender and genetic polymorphisms on matrix metalloprotease (MMP) and tissue inhibitor (TIMP) plasma levels in different infectious and non-infectious conditions

Matrix metalloproteases (MMPs) are increased in different infections due to their role in controlling immune responses and are regulated by tissue inhibitors (TIMPs). Different MMP promoter single nucleotide polymorphisms (SNPs) induce changes in MMP genes, mRNA and protein expression. Gender might also modify MMP plasma levels. In order to determine the weight of these variables on MMP secretion we studied MMP-1, -2, -3, -8, -9, -10, -13 and TIMP-1, -2, -4 plasma levels in 90 patients with severe bacterial sepsis, 102 with anti-retroviral (ARV)-treated HIV monoinfection, 111 with ARV-treated HIV-hepatitis C virus (HCV) co-infection and 86 non-infected controls (45 stroke and 41 trauma patients). MMP-1(-1607 1G/2G), MMP-3(-1612 5A/6A), MMP-8(-799C/T), MMP-9(-1562 C/T) and MMP-13(-77A/G) SNPs were genotyped. MMP-3 plasma levels were significantly higher in men than in women in each diagnostic group, and MMP-3 SNP allele 6A carriers also had higher levels than allele 5A carriers, an effect that was magnified by sepsis. Independent predictors of higher MMP-3 levels were male gender (P = 0.0001), MMP-3(-1612 5A/6A) SNP (P = 0.001), higher levels of TIMP-4 (P = 0.004) and MMP-8 (P = 0.006) and lower levels of MMP-1 (P = 0.03) by multivariate analysis. No strong associations with gender or SNPs were observed for other MMPs or TIMPs. In conclusion, male gender and MMP-3(-1612 5A/6A) 6A allele carriage increased MMP-3 plasma levels significantly, especially in patients with severe bacterial sepsis. This confounding gender effect needs to be addressed when evaluating MMP-3 plasma levels in any infectious or non-infectious condition.

Can antiretroviral therapy be tailored to each human immunodeficiency virus-infected individual? Role of pharmacogenomics

Pharmacogenetics refers to the effect of single nucleotide polymorphisms (SNPs) within human genes on drug therapy outcome. Its study might help clinicians to increase the efficacy of antiretroviral drugs by improving their pharmacokinetics and pharmacodynamics and by decreasing their side effects. HLAB*5701 genotyping to avoid the abacavir-associated hypersensitivity reaction (HSR) is a cost-effective diagnostic tool, with a 100% of negative predictive value, and, therefore, it has been included in the guidelines for treatment of human immunodeficiency virus (HIV) infection. HALDRB*0101 associates with nevirapine-induced HSR. CYP2B6 SNPs modify efavirenz plasma levels and their genotyping help decreasing its central nervous system, hepatic and HSR toxicities. Cytokines SNPs might influence the development of drug-associated lipodystrophy. APOA5, APOB, APOC3 and APOE SNPs modify lipids plasma levels and might influence the coronary artery disease risk of HIV-infected individuals receiving antiretroviral therapy. UGT1A1*28 and ABCB1 (MDR1) 3435C > T SNPs modify atazanavir plasma levels and enhance hyperbilirubinemia. Much more effort needs to be still devoted to complete large prospective studies with multiple SNPs genotyping in order to reveal more clues about the role played by host genetics in antiretroviral drug efficacy and toxicity.

HIV/antiretroviral therapy-related lipodystrophy syndrome (HALS) is associated with higher RBP4 and lower omentin in plasma

Very little information is available on the involvement of newly characterized adipokines in human immunodeficiency virus (HIV)/antiretroviral therapy (ART)-associated lipodystrophy syndrome (HALS). Our aim was to determine whether apelin, apelin receptor, omentin, RBP4, vaspin and visfatin genetic variants and plasma levels are associated with HALS. We performed a cross-sectional multicentre study that involved 558 HIV type 1-infected patients treated with a stable highly active ART regimen, 240 of which had overt HALS and 318 who did not have HALS. Epidemiologic and clinical variables were determined. Polymorphisms in the apelin, omentin, RBP4, vaspin and visfatin genes were assessed by genotyping. Plasma apelin, apelin receptor, omentin, RBP4, vaspin and visfatin levels were determined by enzyme-linked immunosorbent assay in 163 patients (81 with HALS and 82 without HALS) from whom stored plasma samples were available. Student's t test, one-way ANOVA, chi-square test, Pearson and Spearman correlations and linear regression analysis were used for statistical analyses. There were no associations between the different polymorphisms assessed and the HALS phenotype. Circulating RBP4 was significantly higher (p < 0.001) and plasma omentin was significantly lower (p 0.001) in patients with HALS compared to those without HALS; differences in plasma levels of the remaining adipokines were nonsignificant between groups. Circulating RBP4 concentration was predicted independently by the presence of HALS. Apelin and apelin receptor levels were independently predicted by body mass index. Visfatin concentration was predicted independently by the presence of acquired immunodeficiency syndrome. HALS is associated with higher RBP4 and lower omentin in plasma. These two adipokines, particularly RBP4, may be a link between HIV/ART and fat redistribution syndromes.

Endothelial (NOS3 E298D) and inducible (NOS2 exon 22) nitric oxide synthase polymorphisms, as well as plasma NOx, influence sepsis development

INTRODUCTION

Nitric oxide (NO) influences susceptibility to infection and hemodynamic failure (HF) in sepsis. NOS3 and NOS2 SNPs might modify plasma nitrite/nitrate (NOx) levels, sepsis development, hemodynamics and survival.

METHODS

90 severely septic and 91 non-infected ICU patients were prospectively studied. NOS3 (E298D), NOS3 (-786 T/C), NOS3 (27 bp-VNTR), and NOS2A (exon 22) SNPs and plasma NOx levels were assessed.

RESULTS

21 patients (11.6%) died, 7 with sepsis. TT homozygotes and T allele carriers of NOS3 (E298D) and AG carriers of the NOS2A (exon 22) SNPs were more frequent among septic compared to non-infected ICU patients (p < 0.05). Plasma NOx was higher in septic, especially in septic with hemodynamic failure (HF) or fatal outcome (p < 0.006). Plasma NOx was higher in carriers of the T allele of the NOS3 (E298D) SNP (p = 0.006). Sepsis independently associated with HF, increased NOx, peripheral neutrophils, and fibrinogen levels, decreased prothrombin and the presence of the NOS3 (E298D) and NOS2A (exon 22) SNPs. A low APACHE II score was the only variable associated with sepsis survival. NOx was independently associated with sepsis, HF, decreased neutrophils and higher APACHE.

CONCLUSIONS

NOS3 (E298D) and NOS2A (exon 22) SNPs, individually and in combination, and plasma NOx, associated with sepsis development. NOx associated with HF and fatal outcome.

Role of plasma matrix-metalloproteases (MMPs) and their polymorphisms (SNPs) in sepsis development and outcome in ICU patients

Matrix-metalloproteases (MMPs) and their tissue-inhibitors (TIMPs), modulated by different single nucleotide polymorphisms (SNPs), are critical in sepsis development. Ninety ICU severely septic and 91 ICU uninfected patients were prospectively studied. MMP-1 (−1607 1G/2G), MMP-3 (−1612 5A/6A), MMP-8 (−799 C/T), MMP-9 (−1562 C/T), and MMP-13 (−77A/G) SNPs were genotyped. Plasma MMPs (-1, -2, -3, -8, -9, -10, -13) and TIMPs (-1,-2,-4) were measured. AA homozygotes and A allele carriers of MMP-13 (−77 A/G) and 1G2G carriers of the MMP-1 (−1607 1G/2G) SNPs frequencies were different between septic and uninfected patients (p < 0.05), as well as plasma MMP-3, -8, -9 -10 and TIMP-2 levels (p < 0.04). No differences in MMPs levels among MMP-13 or MMP-1 SNPs genotypes carriers were observed. The area under the ROC curve for MMP-8 in the diagnosis of sepsis was 0.87 (95% CI 0.82–0.92), and that of CRP was 0.98 (0.94–0.998), whereas the area of MMP-9 in the detection of non-septic state was 0.73 (0.65–0.80), p < 0.0001 for all curves. Sepsis associated with increased MMP-8 and decreased MMP-9 levels in multivariate analysis (p < 0.0002). We report for the first time an association between MMP-13 and MMP-1 SNPs and sepsis. An independent association of MMP-8 and MMP-9 levels with sepsis was also observed.

Involvement of the LPS-LPB-CD14-MD2-TLR4 inflammation pathway in HIV-1/HAART-associated lipodystrophy syndrome (HALS)

OBJECTIVES

A relationship between obesity and intestinal bacterial translocation has been reported. Very little information is available with respect to the involvement of the bacterial translocation mechanistic pathway in HIV-1/highly active antiretroviral therapy (HAART)-associated lipodystrophy syndrome (HALS). We determined whether lipopolysaccharide (LPS)-binding protein (LBP), cluster of differentiation 14 (CD14), myeloid differentiation protein 2 (MD2) and toll-like receptor 4 (TLR4) single-nucleotide polymorphisms and LPS, LBP and soluble CD14 (sCD14) plasma levels are involved in HALS.

PATIENTS AND METHODS

This cross-sectional multicentre study involved 558 treated HIV-1-infected patients, 240 with overt HALS and 318 without HALS. Anthropometric, clinical, immunovirological and metabolic variables were determined. Polymorphisms were assessed by genotyping. Plasma levels were determined by ELISA in 163 patients (81 with HALS and 82 without HALS) whose stored plasma samples were available. Student's t-test, one-way ANOVA, two-way repeated measures ANOVA, the χ(2) test and Pearson and Spearman correlation analyses were carried out for statistical analysis.

RESULTS

LBP rs2232582 T→C polymorphism was significantly associated with HALS (P = 0.01 and P = 0.048 for genotype and allele analyses, respectively). Plasma levels of LPS (P = 0.009) and LBP (P < 0.001) were significantly higher and sCD14 significantly lower (P < 0.001) in patients with HALS compared with subjects without HALS. LPS levels were independently predicted by triglycerides (P < 0.001) and hepatitis C virus (P = 0.038), LBP levels by HALS (P < 0.001) and sCD14 levels by age (P = 0.008), current HIV-1 viral load (P = 0.001) and protease inhibitor use (P = 0.018).

CONCLUSIONS

HALS is associated with LBP polymorphism and with higher bacterial translocation.

tPA Alu (I/D) polymorphism associates with bacterial osteomyelitis

BACKGROUND

Coagulation and fibrinolysis are important in infections and systemic inflammatory response syndrome. Polymorphisms in plasminogen activator inhibitor-1 (PAI-1, SERPINE1) and tissue plasminogen activator (tPA, PLAT), such as PAI-1 (-675 4G/5G deletion/insertion) and tPA (Alu insertion/deletion [I/D]), are associated with strokes, myocardial infarctions, bacterial infections and septic shock severity, and trauma. Osteomyelitis is a mostly posttraumatic, Staphylococcal bone infection.

PATIENTS AND METHODS

tPA Alu (I/D) (rs4646972) and PAI-1 (4G/5G) (rs1799889) polymorphisms were studied by DNA amplification with polymerase chain reaction in 261 patients with osteomyelitis and in 299 matched blood donors. Plasma PAI-1/tPA complex was assessed by enzyme-linked immuosorbent assay.

RESULTS

II homozygotes (37.9% vs 19.1%) and I allele carriers (56.3% vs 46.3%) for the tPA Alu (I/D) polymorphism were significantly more frequent in osteomyelitis patients compared to controls (P < .001). II genotype carrier osteomyelitis patients had lower PAI-1/tPA complex levels compared to those with the D allele (P ≤ .04). There was no association between these genotypes and chronicity of osteomyelitis, post-traumatic etiology, or with a specific bacterial etiology. PAI-1 (4G/4G) homozygotes were not significantly different between osteomyelitis patients and controls (P = .1).

CONCLUSIONS

We report for the first time to our knowledge an association between the tPA Alu (I/D) polymorphism and susceptibility to bacterial osteomyelitis, perhaps by fibrinolysis dysfunction.

Didanosine (ddI) associates with increased liver fibrosis in adult HIV-HCV coinfected patients

The role of exposure to antiretrovirals (ARV) and serum matrix metalloproteases (MMPs) on liver fibrosis (LF) progression in human immunodeficiency virus (HIV) mono or HIV- hepatitis C virus (HCV) coinfection is unclear. Thus, 213 Caucasian adult HIV-infected patients were studied, 111 of whom had HCV-coinfection and 68 were HCV-monoinfected. Patients with ethanol consumption >50 g/day, hepatitis B coinfection, non-infective liver diseases or HAART adherence <75% were excluded. LF was assessed by transient elastometry (TE, Fibroscan). Serum levels of MMPs (MMP -1,-2,-3,-8,-9,-10 and -13) and their tissue inhibitors (TIMP-1,-2 and -4) were measured by ELISA microarrays. Associations with LF were statistically analysed. Protease inhibitors, usually administered to patients with advanced LF were excluded from the analysis. Increased LF was significantly associated with d4T (P = 0.006) and didanosine (ddI) use (P = 0.007), months on d4T (P = 0.001) and on ARV (P = 0.025), duration of HIV (P < 0.0001) and HCV infections (P < 0.0001), higher HIV (P = 0.03) and HCV loads (P < 0.0001), presence of lipodystrophy (P = 0.02), male gender (P = 0.02), older age (P = 0.04), low nadir (P = 0.02) and current CD4(+) T-cells (P < 0.0001), low gain of CD4(+) T-cells after HAART (P = 0.01) and higher MMP-2 (P = 0.02) and TIMP-2 serum levels (P = 0.02). By logistic regression the only variables significantly associated with increased LF were: use of ddI (OR 8.77, 95% CI: 2.36-32.26; P = 0.005), male gender (OR 7.75, 95% CI: 2.33-25.64, P = 0.0008), HCV viral load (in log) (OR 3.53, 95% CI: 2.16-5.77; P < 0.0001) and age (in years) (OR 1.21, 95% CI: 1.09-1.34, P = 0.0003). We conclude that only higher HCV viral load, older age, male gender, and use of ddI associated independently with increased LF in our study.

The IL-1β (+3953 T/C) gene polymorphism associates to symptomatic lumbar disc herniation

PURPOSE

To determine whether polymorphisms (SNPs) in the genes encoding cytokines and nitric oxide synthase (NOS) might play some role in lumbar disc herniation (LDH).

PATIENTS AND METHODS

Case-control study in which 179 patients were retrospectively reviewed. The case group was made of 50 patients with symptomatic LDH diagnosed by MRI while the control group was made of 129 individuals undergoing routine hip or knee arthroplasty with a lifetime lack of low back pain. SNPs in the cytokine genes of IL-1 [IL-1α (-889 C/T), IL-1β (+3953 T/C)], TNF-α (-308 G/A and -238 G/A) and NOS genes [eNOS (r 27 bp, intron 4 and -786 T/C) and iNOS (22 G/A)].

RESULTS

The CC genotype and C allele of the IL-1β (+3953 T/C) SNP were significantly more frequent among LDH patients compared to controls. On the other hand, eNOS (-768 T/C) and iNOS (22 G/A) SNPs were significantly more common in the control group.

CONCLUSIONS

Carriers of the CC genotype of the IL-1β (+3953 T/C) SNP were more frequent among LDH patients suggesting some potential role of the IL-1β SNP on LDH pathogenesis. The eNOS (-786 T/C) and iNOS (22 G/A) SNPs were more frequent among the control subjects, suggesting their possible protective role against LDH. Genotyping these SNPs could be useful to identify persons with an increased lifetime risk of disc herniation in whom measures to avoid LDH could be implemented.

Autoregulation mechanism of human neutrophil apoptosis during bacterial infection

Neutrophils (PMN), potent phagocytes, are the first line of the host immune defence against microorganisms, especially bacteria. Their half-life is very short and they are eliminated through apoptosis. Delayed neutrophil apoptosis is a characteristic feature of human osteomyelitis arising from Gram-negative or Gram-positive bacterial infection. The aim of this study was to investigate the modulation of apoptosis during infection of the human neutrophils by Staphylococcus aureus or Escherichia coli, the most common isolate in osteomyelitis. Analysis of host cells by flow cytometry using propidium iodide or annexin V labelling revealed an apoptosis inhibition after bacterial infection or treatment with LPS or LTA. We detected the secretion of cytokines such as IL-6, TNF-alpha and IL-1 beta by infected neutrophils. The addition of monoclonal antibodies to each cytokine abolished the protection against apoptosis. The anti-apoptotic Bcl-x(L) protein expression was increased and the pro-apoptotic Bax-alpha protein expression was decreased. These results identify a novel apoptotic effect in bacteria-infected cells that is mainly dependent on auto-production of cytokines and is correlated with Bax-alpha/Bcl-x(L) ratio. This may be a mechanism through which to resolve bacterial osteomyelitis infection.

Bax gene G(-248)A promoter polymorphism is associated with increased lifespan of the neutrophils of patients with osteomyelitis

BACKGROUND

Patients with osteomyelitis have a decreased rate of spontaneous apoptosis of their peripheral blood neutrophils. The G(-248)A polymorphism in the promoter region of the bax gene is associated with prolonged peripheral blood neutrophil survival in leukemic patients and may play some role in osteomyelitis.

METHODS

Bax G(-248)A promoter polymorphism was detected by DNA amplification using polymerase chain reaction, followed by restriction fragment length polymorphism analysis. Spontaneous apoptosis of peripheral blood neutrophils was measured by propidium iodide, annexin V, and flow cytometry, and Bax was quantified by Western blotting.

RESULTS

The bax promoter polymorphism A allele was significantly more frequent in 80 patients with osteomyelitis than in 220 healthy donors (18.1% vs. 10.6%, chi=4.84, odds ratio=1.81, 95% confidence interval=1.06-3.07, P=.028). Carriers of the A allele had a lower apoptotic rate of their peripheral blood neutrophils compared with noncarriers (33.3+/-16.7 vs. 43.1+/-3.1, P=.036). Patients with the AA genotype showed a lower expression of the Bax protein compared with carriers of other genotypes (P=.038).

CONCLUSIONS

Substitution of a nucleotide G-->A at position -248 in the bax gene was more frequent in patients with osteomyelitis and was associated with a longer lifespan of their peripheral blood neutrophils and lower Bax protein expression. These findings may play a role in the pathogenesis of osteomyelitis.