Management of allergy transfer upon solid organ transplantation

Allergy transfer upon solid organ transplantation has been reported in the literature, although only few data are available as to the frequency, significance, and management of these cases. Based on a review of 577 consecutive deceased donors from the Swisstransplant Donor-Registry, 3 cases (0.5%) of fatal anaphylaxis were identified, 2 because of peanut and 1 of wasp allergy. The sera of all 3 donors and their 10 paired recipients, prospectively collected before and after transplantation for the Swiss Transplant Cohort Study, were retrospectively processed using a commercial protein microarray fluorescent test. As early as 5 days posttransplantation, newly acquired peanut-specific IgE were transiently detected from 1 donor to 3 recipients, of whom 1 liver and lung recipients developed grade III anaphylaxis. Yet, to define how allergy testing should be performed in transplant recipients and to better understand the impact of immunosuppressive therapy on IgE sensitization, we prospectively studied 5 atopic living-donor kidney recipients. All pollen-specific IgE and >90% of skin prick tests remained positive 7 days and 3 months after transplantation, indicating that early diagnosis of donor-derived IgE sensitization is possible. Importantly, we propose recommendations with respect to safety for recipients undergoing solid-organ transplantation from donors with a history of fatal anaphylaxis.

Cell-free nucleic acids are present in blood products and regulate genes of innate immune response

BACKGROUND

Extracellular nucleic acids circulate in plasma. They are expected to be present in manufactured blood products eligible for transfusion, but little is known about their biological activity on human cells. The aim of this study is to investigate whether cell-free nucleic acids (CFNAs) are present and biologically active in red blood cell units (RBCUs), fresh frozen plasmas, and platelet concentrates.

STUDY DESIGN AND METHODS

CFNAs were extracted from RBCUs, fresh frozen plasma, and platelet concentrates. Their nature and structure were analyzed by regular methods of nucleic acid detection/quantification. A normalized polymerase chain reaction combining amplification of a CFNA marker (Alu 115) and amplification of an internal nonhuman DNA control spiked in all samples (phiX 174) was developed to study CFNA release after RBCU storage. The impact of CFNAs on gene regulation was tested by microarray after coculture with peripheral blood mononuclear cells and macrophages.

RESULTS

Extracellular double-stranded DNA was present in all blood products, with higher amounts found in cellular suspensions (RBCUs and platelet concentrates). Storage up to 40 days did not influence release from RBCUs, and CFNA amount varied considerably from one unit to another. Microarray experiments showed that exposition of macrophages to CFNA increased the expression of genes involved in the innate immune response including chemokines, chemokine receptors, and receptors of the innate response.

CONCLUSION

CFNAs are present in blood products. Immunoregulatory properties of CFNA are shown in vitro, providing new insights on biologically active components of blood products besides those for intended therapeutic use.

Impact of exercise training without caloric restriction on inflammation, insulin resistance and visceral fat mass in obese adolescents

BACKGROUND

Exercise training has been shown to improve cardiometabolic health in obese adolescents.

OBJECTIVES

Evaluate the impact of a 12-week exercise-training programme (without caloric restriction) on obese adolescents' cardiometabolic and vascular risk profiles.

METHODS

We measured systemic markers of oxidation, inflammation, metabolic variables and endothelial function in 20 obese adolescents (OB) (age: 14.5 ± 1.5 years; body mass index: 34.0 ± 4.7 kg m(-2) ) and 20 age- and gender-matched normal-weight adolescents (NW). Body composition was assessed by magnetic resonance imagery. Peak aerobic capacity and maximal fat oxidation were evaluated during specific incremental exercise tests. OB participated in a 12-week exercise-training programme.

RESULTS

OB presented lower peak aerobic capacity (24.2 ± 5.9 vs. 39.8 ± 8.3 mL kg(-1)  min(-1) , P < 0.05) and maximal fat oxidation compared with NW (P < 0.05). OB displayed greater F2t-Isoprostanes (20.5 ± 6.7 vs. 13.4 ± 4.2 ng mmol(-1) creatinine), Interleukin-1 receptor antagonist (IL-1Ra) (1794.8 ± 532.2 vs. 835.1 ± 1027.4 pg mL(-1) ), Tumor Necrosis Factor-α (TNF-α) (2.1 ± 1.2 vs. 1.5 ± 1.0 pg mL(-1) ), Soluble Tumor Necrosis Factor-α Type II Receptor (sTNFαRII), leptin, insulin, homeostasis model assessment of insulin resistance, version 2 (HOMA2-IR), high-sensitive C-reactive protein, triglycerides and lower adiponectin and high-density lipoprotein cholesterol (all P < 0.05). After exercise training, despite lack of weight loss, VO2peak (mL.kg(-1) .min(-1) ) and maximal fat oxidation increased (P < 0.05). IL-1Ra and IFN-gamma-inducible protein 10 (IP-10) decreased (P < 0.05). Insulin and HOMA2-IR decreased (14.8 ± 1.5 vs. 10.2 ± 4.2 μUI mL(-1) and 1.9 ± 0.8 vs. 1.3 ± 0.6, respectively, P < 0.05). Change in visceral fat mass was inversely associated with change in maximal fat oxidation (r = -0.54; P = 0.024). The subgroup of participants that lost visceral fat mass showed greater improvements in triglycerides, insulin resistance and maximal fat oxidation.

CONCLUSION

Our data confirms the role of exercise training on improving the inflammatory profile and insulin resistance of OB in the absence of weight loss. However, those who lost a greater amount of visceral fat mass showed greater benefits in terms of insulin profile, triglycerides and maximal fat oxidation.

Procalcitonin, IL-6, IL-8, IL-1 receptor antagonist and C-reactive protein as identificators of serious bacterial infections in children with fever without localising signs

Fever without localising signs in very young children remains a diagnostic problem. Until present, a clinical scoring system combined with leucocyte count, urine analysis and determination of CRP are recognised as being helpful to identify patients at risk of serious bacterial illness. In this study we asked the question whether the determination of procalcitonin (PCT), interleukin (IL)-6, IL-8 and interleukin-1 receptor antagonist (IL- Ra) was superior to these commonly used markers for the prediction of a serious bacterial infection (SBI). Children, 7 days to 36 months of age, with a rectal temperature above 38 degrees C and without localising signs of infection were prospectively enrolled. For each infant, we performed a physical examination, a clinical score according to McCarthy, a complete white cell count, an urine analysis and a determination of CRP. We further determined PCT, IL-6, IL-8, and IL-1Ra concentrations and compared their predictive value with those of the usual management of fever without localising signs. Each infant at risk of SBI had blood culture, urine and cerebrospinal fluid cultures when indicated, and received antibiotics until culture results were available. A total of 124 children were included of whom 28 (23%) had SBI. Concentrations of PCT, CRP and IL-6 were significantly higher in the group of children with SBI but IL-8 and IL-1Ra were comparable between both groups. PCT showed a sensitivity of 93% and a specificity of 78% for detection of SBI and CRP had a sensitivity of 89% and a specificity of 75%.

CONCLUSION

Compared to commonly used screening methods such as the McCarthy score, leucocyte count and other inflammatory markers such as interleukin-6, interleukin-8 and interleukin- receptor antagonist, procalcitonin and C-reactive protein offer a better sensitivity and specificity in predicting serious bacterial infection in children with fever without localising signs.

Tumour necrosis factor alpha and its soluble receptors in juvenile chronic arthritis

OBJECTIVE

To identify possible imbalance of tumour necrosis factor alpha (TNFalpha) and its soluble receptors in the different subgroups of juvenile chronic arthritis (JCA).

METHODS

Serum and synovial fluid samples from 45 children were examined, 25 pauciarticular JCA, 13 polyarticular JCA and seven spondyloarthropathy. TNFalpha, sTNFRI and sTNFRII levels were measured by EASIA and enzyme-linked immunosorbent assay (ELISA). Analysis of the results was carried out using non-parametric tests: Kruskal-Wallis one-way analysis of variance was used to compare the three clinical subgroups; the Mann-Whitney U-test was used to compare group medians.

RESULTS

Thirty-three serum samples were assayed for TNFalpha. There was no significant difference between the three groups using the Kruskal-Wallis analysis of variance. Analysis of synovial fluid TNF levels showed significantly lower levels in the spondyloarthropathy group compared with the pauciarticular JCA (P = 0.01) and the polyarticular group (P = 0.002). Significantly higher levels of sTNFRI were observed in the synovial fluid of the polyarticular JCA group compared with the pauciarticular JCA group (P = 0.004) and similarly for sTNFRII (P = 0.03). Molar ratios were calculated for TNF vs sTNFRI. The sTNFRI/TNFalpha ratio was significantly higher in the spondyloarthropathy group compared with the pauci- (P 0.003) and the polyarticular JCA subgroups (P = 0.003). The combined soluble receptor levels expressed as molar ratio to TNF again showed a significantly higher ratio in the spondyloarthropathy group compared with the pauciarticular group (P = 0.01) and compared with the polyarticular group (P = 0.05).

CONCLUSION

These results suggest that the increased joint destruction observed in polyarticular disease compared with the other two subtypes may be related to the lower sTNFR/TNFalpha ratios observed.