Kidney Transplantation, Polymorphisms of IL-18, and Other Pro-Inflammatory Genes and Late Post-Transplant Outcome

Investigation of the Relationship Between IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) Gene Variations and Serum Copper and Zinc Levels in Patients Diagnosed with Chronic Renal Failure

The aim of this study is to investigate the relationship between IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) gene variations and serum trace element levels in patients diagnosed with CRF. Genotype distributions of IL-18 (- 607 C/A, - 137 G/C) gene variations were determined by polymerase chain reaction (PCR) method. PCR-restriction fragment length polymorphism (RFLP) methods were used to determine the MMP-2 (- 1306 C/T) gene variation genotype distributions. Serum trace element levels were determined by atomic absorption spectrophotometer method. A significant difference was found between the CRF patient and healthy control groups in terms of genotype distributions of IL-18 (- 607 C/A) and MMP-2 (- 1306 C/T) gene variations (p < 0.05). The significant difference was found between the patient and control groups in terms of serum copper and zinc levels and copper/zinc ratio (p < 0.05). The significant difference was detected between patient and control groups in terms of copper and zinc levels and copper/zinc ratio according to IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) gene variations and genotype distributions (p < 0.05). In addition, significant difference was determined in terms of serum copper and zinc levels and copper/zinc ratio according to haplotypes of IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) gene variations between patient and control groups (p < 0.05). In conclusion, evaluation of IL-18 (- 607 C/A, - 137 G/C) and MMP-2 (- 1306 C/T) gene variations and serum trace element levels together is extremely important in terms of obtaining important biomarkers in CRF early diagnosis and progression.

Influence of Interferon Gamma +874 T>A (rs2430561) Polymorphism on Renal Allograft Rejection: A Meta-analysis

BACKGROUND

Reported associations of the interferon gamma (IFNG) +874T/A (rs2430561) polymorphism with post-kidney transplantation allograft rejection (AR) have been inconsistent, prompting a meta-analysis to obtain more precise estimates.

METHODS

Eighteen articles (22 studies) were included in the meta-analysis. Operating on the hypothesis that IFNG rs2430561 either increases or reduces AR risk, we used a genetic model-free approach to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Subgrouping was based on ethnicity (white, Middle Eastern, black, and mixed) and rejection type (ACR: acute rejection and CHR: chronic rejection). Quality of the associative effects was assessed with sensitivity treatment and test for publication bias.

RESULTS

The overall analysis in the dominant model indicated increased risk (OR = 1.26; P^a = .02) was validated in the ACR subgroup (OR = 1.29; P^a = .01), which contrasted with the CHR subgroup, with a nonsignificant effect indicating reduced risk (OR = 0.83; P^a = .68). Only the black subgroup showed significant increased risk (OR = 2.87; P^a = .04), but the association was tenuous on account of low sample size (n = 2) and imprecise effect (95% CI, 1.07-7.73).

CONCLUSIONS

Increased risk associations (overall and ACR) of IFNG rs2430561 with AR is significant, robust, statistically powered, and lacking bias. Contrasting ACR (1.3-fold increased risk) and CHR (7% protective) effects may be clinically relevant in the genetics of renal transplantation.

Direct peritoneal resuscitation reduces inflammation in the kidney after acute brain death

Brain death is associated with significant inflammation within the kidneys, which may contribute to reduced graft survival. Direct peritoneal resuscitation (DPR) has been shown to reduce systemic inflammation after brain death. To determine its effects, brain dead rats were resuscitated with normal saline (targeted intravenous fluid) to maintain a mean arterial pressure of 80 mmHg; DPR animals also received 30 cc of intraperitoneal peritoneal dialysis solution. Rats were euthanized at 0, 2, 4, and 6 h after brain death. Pro-inflammatory cytokines were measured using ELISA. Levels of IL-1β, TNF-α, and IL-6 in the kidney were significantly increased as early as 2 h after brain death and significantly decreased with DPR. Levels of leukocyte adhesion molecules ICAM and VCAM increased after brain death and were decreased with DPR (ICAM 2.33 ± 0.14 vs. 0.42 ± 0.04, P = 0.002; VCAM 82.6 ± 5.8 vs. 37.3 ± 1.9, P = 0.002 at 4 h) as were E-selectin and P-selectin (E-selectin 25,605 vs. 16,144, P = 0.005; P-selectin 82.5 ± 3.3 vs. 71.0 ± 2.3, P = 0.009 at 4 h). Use of DPR reduces inflammation and adhesion molecule expression in the kidneys, and is associated with reduced macrophages and neutrophils on immunohistochemistry. Using DPR in brain dead donors has the potential to reduce the immunologic activity of transplanted kidneys and could improve graft survival.