The value of serum neopterin, interferon-gamma levels and interleukin-12B polymorphisms in predicting acute renal allograft rejection.

Acute rejection remains a poor predictor of graft outcome. In this study, we measured serum levels of interferon (IFN)-gamma and neopterin by enzyme-linked immunosorbent assay and a single nucleotide polymorphism (SNP) within the 3' untranslated region of the interleukin (IL)-12 B gene (1188 A/C) to determine whether either of these factors could predict acute rejection in renal transplantation. Significantly higher early post-transplant neopterin levels (days 5-7; 35.7 versus 19.9 nmol/l) were observed in recipients who subsequently rejected their grafts. Post-transplant neopterin levels showed a strong positive correlation with 1-month creatinine levels (Spearman's correlation 0.62, P < 0.001), suggesting macrophage activation early after transplantation. Pretransplant neopterin and IFN-gamma levels and the IL-12B gene SNP did not predict acute rejection in this small retrospective study. The ability to predict acute rejection non-invasively early after transplantation could lead to individual tailoring of immunosuppressive regimens and perhaps lead eventually to longer graft survival.

Effect of stress on basophil function in chronic idiopathic urticaria.

BACKGROUND: Chronic idiopathic urticaria (CIU) is a distressing skin condition involving recurrent itchy hives lasting 6 weeks or longer. The mechanism involves mast cell and basophil degranulation, which releases inflammatory mediators including histamine. In our clinical practice, we have observed that the onset of CIU is often preceded by a major life event. OBJECTIVE: To investigate the role of the hormones of the hypothalamic-pituitary-adrenal (HPA) axis in the link between psychological stress and CIU. METHODS: Thirty people with CIU and 30 normal controls were recruited. A flow cytometric CD63 expression assay was used to quantify basophil activation, and serum cortisol concentrations were measured as an indication of stress. RESULTS: Both corticotrophin releasing factor (CRF) and adrenocorticotrophic hormone (ACTH) were shown to activate basophils. There was no significant difference between numbers of CIU patients and normal controls responding to CFR, ACTH or cortisol. However, the responses in the CIU patients were stronger than those in normal controls. There was also a trend towards higher serum cortisol concentrations in CIU patients. The basophil response to CRF and ACTH correlated with the serum cortisol concentration in normal controls, but not in CIU patients. CONCLUSIONS: Although our data have not supported the hypothesis that stress makes a major contribution to CIU, the heightened basophil response to CFR and ACTH and higher levels of serum cortisol do suggest a derangement of the HPA axis in CIU.

Tumour necrosis factor alpha promoter polymorphism at position -308 is not associated with actinic prurigo.

Actinic prurigo (AP) has been found to be strongly associated with HLA DR4 and in particular with the DR4 subtype DRB1*0407. However, AP may occur in the absence of HLA-DR4. Furthermore, it has been shown that HLA-DR4 and DRB1*0407, even in association with polymorphic light eruption (PLE), are insufficient for the expression of the AP phenotype. It seems likely, therefore, that other genes in the HLA DR or adjacent regions may contribute to AP susceptibility. One possible predisposing factor in AP may be tumour necrosis factor (TNF)alpha as suggested by the good response of AP to the TNFalpha inhibitor thalidomide, and by the involvement of this cytokine in many immune responses. The aim of this study was to explore the relationship between AP and TNFalpha by examining the frequency of TNF2 in patients with AP, PLE and in normal controls. TNF1 and TNF2 are biallelic polymorphisms at position -308 of the TNFalpha gene promoter and are known to affect transcription of TNFalpha. TNF2 is the rarer of the two alleles and is associated with high functional levels of TNFalpha. This study confirms the positive linkage disequilibrium that has been described between HLA DR3 and TNF2, but fails to show an association between TNF2 and AP.

A candidate gene analysis of three related photosensitivity disorders: cutaneous lupus erythematosus, polymorphic light eruption and actinic prurigo.

BACKGROUND: Polymorphic light eruption (PLE) is a common inherited photosensitivity disorder, which may predispose to several related but distinct conditions, including subacute cutaneous lupus erythematosus (SCLE), discoid lupus erythematosus (DLE) and actinic prurigo (AP). OBJECTIVES: To examine specific candidate genes for shared susceptibility alleles between these related phenotypes. METHODS: Eighty-five caucasian patients with annular SCLE or DLE were recruited, in addition to 102 first-degree relatives. The prevalence of PLE in both the patient and relative groups was determined by detailed interview and clinical examination. Eighty-five patients with pure PLE and 59 patients with AP were also recruited. Candidate genes were analysed by typing of single nucleotide polymorphisms of IL10 (-1082 G/A and -819 C/T), FCGR2A (131 R/H), SELE (128 S/R), ICAM1 (241 G/R and 469 E/K), IL1A (+ 4845 G/T), IL1B (-511 C/T and + 3954 C/T), IL1RN (+ 2018 T/C) and TNF (-308 G/A) using polymerase chain reaction (PCR) with sequence-specific primers and 5'-nuclease PCR. RESULTS: A significant association was found between SCLE and the rare TNF -308 A allele when compared with patients with DLE (P = 0.043), PLE (P = 0.001), AP (P < 0.001) and healthy controls (P < 0.001). However, there was strong linkage disequilibrium between TNF -308 A and the HLA A*01, B*08, DRB1*0301 haplotype. A negative association was also found between SCLE and the IL1B + 3954 T allele (P = 0.039), but the significance was lost on correction for multiple testing. CONCLUSIONS: We have demonstrated the association of SCLE with the rare TNF -308 A allele, which may be pathogenic or, alternatively, a marker allele for the extended HLA A*01, B*08, DRB1*0301 haplotype that is associated with a number of autoimmune conditions. Although many of the other loci that we chose failed to demonstrate an association, a candidate gene approach remains the most logical one, and the most likely to yield positive results in the future.

Prevention of hyperacute rejection by removal of antibodies to HLA immediately before renal transplantation.

BACKGROUND: Many patients with circulating antibodies to human leucocyte antigens (anti-HLA) are highly sensitised against renal transplantation and are liable to immediate graft loss through hyperacute rejection. Our aim was to find out whether removal of anti-HLA immediately before renal transplantation prevented hyperacute graft rejection. METHODS: 13 highly sensitised patients underwent cadaveric renal transplants immediately after immunoadsorption (IA) treatment to remove anti-HLA. Before IA, 12 patients had a positive crossmatch against donor cells either by cytotoxic or flow-cytometric assay; results for one patient were equivocal. FINDINGS: Renal biopsy samples were obtained 20 min after removal of the vascular clamps in nine patients. There was no evidence of hyperacute rejection in six of the nine patients; the other three patients showed glomerular thrombosis but no other evidence of hyperacute rejection. Two of these three grafts were functioning at 31 months of follow-up. Six episodes of acute rejection occurred in five patients during the first month after transplantation and overall there were 13 rejection episodes in nine patients. At latest follow-up (median 26 months, range 9-42), 12 of 13 patients were alive and seven of 13 grafts were surviving with a median plasma creatinine concentration of 185 mumol/L (range 106-296) in the functioning grafts. No graft was lost as a result of classic hyperacute rejection. INTERPRETATION: Immediate pretransplant IA can prevent hyperacute rejection and provide an opportunity for successful transplantation in highly sensitised patients.

Anticipation of highly sensitised renal patients' immunoadsorption requirements by prescreening using protein A minicolumns.

We are able to subdivide highly sensitised renal patients who wish to enter our immunoadsorption programme into two groups; those who will require acute pretransplant immunoadsorption only and those requiring regular immunoadsorption prior to transplantation. This division of patients is based on the results obtained from laboratory assessment using protein A minicolumns. Patient's plasma is passed down a minicolumn for 6 x 10 min cycles, a sample of plasma is kept after each cycle for analysis by cell flow cytometric cross-match (FCXM). The samples are screened against cells from two normal volunteers, one expressing a previously mismatched Class I HLA antigen (MMA) to which the patient has raised persistent IgG antibodies, the other, whilst not expressing any MMAs, should express a cross-reactive HLA Class I antigen (XRA) to which the patient has formed persistent IgG antibodies. Patients are allocated into the acute pretransplant immunoadsorption group if, after 6 minicolumn cycles, the T cell FCXM vs XRA and MMA is reduced to less than 1 Log median fluorescence intensity shift above the negative control and that both these values have been reduced by at least 15% from the preimmunoadsorption figure. If these criteria are not met, regular immunoadsorption is required under cover of cyclophosphamide. Eleven patients who have been allocated by these criteria have subsequently been transplanted without any incidence of hyperacute rejection.

Antibody removal and subsequent transplantation of a highly sensitised paediatric renal patient.

We report a successful renal transplant in a highly sensitised paediatric recipient following removal of HLA-specific antibodies by extracorporeal immunoadsorption. The immediate pretransplant cytotoxic titre against the donor was greater than 1:512; this was reduced to negativity by two immunoadsorption sessions prior to transplant surgery. We also describe the presence of unexpected non-HLA-specific antibody activities in this immunoadsorbed patient.

The specificity of antibodies induced by infection with rhinovirus type 2.

Mouse monoclonal antibodies (MAbs) against three distinct antigenic sites on rhinovirus type 2 have been obtained and the sites identified. We describe how these MAbs were used in a blocking test to detect antibodies in human sera directed against the same three defined sites. Sera from twelve volunteers were studied. All had been exposed to rhinovirus type 2 by intranasal inoculation, four had been uninfected, eight were infected of whom four developed a cold while four did not. Blocking antibodies were high and did not increase in the resistant volunteers, and were lower and increased in the infected volunteers. The antibodies were almost as sensitive as other antibody assays for detecting infection. The responses to all three sites were similar. Correlations between the results of all tests were calculated and the results are summarised. Tests were also devised to measure the Ig subclass of antibodies against the whole virus particle. The A1, G1, and G4 classes showed most frequent rises in response to infection. Correlations between these results and other antibody assays were found and are presented.