Size and Composition of T-Cell Receptor δ (TCRD) Junctional Sequences Are Not Predictive of the Sensitivity of Clonospecific Oligonucleotides Designed for Detection of Minimal Residual Disease in Acute Lymphoblastic Leukemia

We characterized 168 junctional regions of T-cell receptor delta (TCRD) rearrangements from 116 children with acute lymphoblastic leukemia (ALL) (101 with precursor B-cell ALL, 15 with T-cell ALL). Application of 101 allele-specific oligonucleotide (ASO) probes representing 85 Vdelta2Ddelta3, 10 Ddelta2Ddelta3, 3 Vdelta1Jdelta1, 1 Vdelta3Jdelta1, and 2 Ddelta2Jdelta1 junctions for the detection of minimal residual disease (MRD) revealed detection levels of 10(-4) to 10(-6) leukemia cells in the vast majority of cases (93 of 101). Of interest was that neither the N, D, P (nontemplated, diversity, palindromic) content and length of the junctional regions nor the number of nucleotides deleted from the flanking V, D, or J (variable, diversity, joining) elements correlated with the sensitivity of ASO probes. These data indicated that in ALL TCRD rearrangements can serve as suitable tools for the detection of MRD irrespective of the specific composition of the junctional region.     

Combinatorial detection of autoreactive CD8<Superscript>+</Superscript> T cells with HLA-A2 multimers: a multi-centre study by the Immunology of Diabetes Society T Cell Workshop

Aims/hypothesis

Validated biomarkers are needed to monitor the effects of immune intervention in individuals with type 1 diabetes. Despite their importance, few options exist for monitoring antigen-specific T cells. Previous reports described a combinatorial approach that enables the simultaneous detection and quantification of multiple islet-specific CD8⁺ T cell populations. Here, we set out to evaluate the performance of a combinatorial HLA-A2 multimer assay in a multi-centre setting.

Methods

The combinatorial HLA-A2 multimer assay was applied in five participating centres using centralised reagents and blinded replicate samples. In preliminary experiments, samples from healthy donors were analysed using recall antigen multimers. In subsequent experiments, samples from healthy donors and individuals with type 1 diabetes were analysed using beta cell antigen and recall antigen multimers.

Results

The combinatorial assay was successfully implemented in each participating centre, with CVs between replicate samples that indicated good reproducibility for viral epitopes (mean %CV = 33.8). For beta cell epitopes, the assay was very effective in a single-centre setting (mean %CV = 18.4), but showed sixfold greater variability across multi-centre replicates (mean %CV = 119). In general, beta cell antigen-specific CD8⁺ T cells were detected more commonly in individuals with type 1 diabetes than in healthy donors. Furthermore, CD8⁺ T cells recognising HLA-A2-restricted insulin and glutamate decarboxylase epitopes were found to occur at higher frequencies in individuals with type 1 diabetes than in healthy donors.

Conclusions/interpretation

Our results suggest that, although combinatorial multimer assays are challenging, they can be implemented in multiple laboratories, providing relevant T cell frequency measurements. Assay reproducibility was notably higher in the single-centre setting, suggesting that biomarker analysis of clinical trial samples would be most successful when assays are performed in a single laboratory. Technical improvements, including further standardisation of cytometry platforms, will likely be necessary to reduce assay variability in the multi-centre setting.

     

Multislice CT angiography in the follow-up of fenestrated endovascular grafts: effect of slice thickness on 2D and 3D visualization of the fenestration stents

PURPOSE: To investigate the effect of multislice computed tomography (CT) protocols on the visualization of target vessel stents in patients with abdominal aortic aneurysm (AAA) treated with fenestrated endovascular grafts. METHODS: Twenty-one patients (19 men; mean age 75 years, range 63-86) undergoing fenestrated endovascular repair of AAA were retrospectively studied. Multislice CT angiography was performed with several protocols, and the section thicknesses used in each were compared to identify any relationship between slice thickness and target vessel stents visualized on 2-dimensional (2D) axial, multiplanar reformatted (MPR), and 3-dimensional (3D) virtual intravascular endoscopy (VIE) images. Image quality was assessed based on the degree of artifacts and their effect on the ability to visualize the configuration, intra-aortic location, and intraluminal appearance of the target vessel stents and measure their protrusion into the aortic lumen. RESULTS: There were 7 different multislice CT scanning protocols employed in the 21 patients (25 datasets, with 2 sets of follow-up images in 4 patients). The slice thicknesses and numbers (n) of studies included were 0.5 (n=3), 0.625 (n=6), 1.0 (n=1), 1.25 (n=9), 2.5 (n=3), 3.0 (n=1), and 5.0 mm (n=2). Of these CT protocols, images (especially 2D/3D reconstructions) acquired at 2.5, 3.0, and 5.0 mm were significantly compromised by interference from artifacts. Images acquired with a slice thickness of 1.0 or 1.25 mm were scored equal to or lower than those acquired with a submillimeter section thickness (0.5 or 0.625 mm), with minor degrees of artifacts resulting in acceptable image quality. CONCLUSION: Visualization of the target vessel stents depends on the appropriate selection of multislice CT scanning protocols. Our results showed that studies performed with a slice thickness of 1.0 or 1.25 mm produced similar image quality to those with a thickness of 0.5 or 0.625 mm. Submillimeter slices are not recommended in imaging patients treated with fenestrated stent-grafts, as they did not add additional information to the visualization.     

Risk factors for domestic sporadic campylobacteriosis among young children in Sweden

A case-control study was conducted in Sweden to study risk factors for domestically acquired Campylobacter jejuni/coli infections among children aged less than 6 y. A total of 126 cases, reported to the national surveillance system were recruited over 1 y. Controls, selected from the population register, were matched to the cases by age, gender, place of residence and time of infection of the case. Information was gathered by posted questionnaires. Two separate conditional regression models were developed including and excluding 'protective' factors. Two of the factors significantly associated with Campylobacter infection were water-related: having a well in the household (OR=2.6) and drinking water from a lake/river (OR=7.4; 6.0). Other exposures associated with increased risk were: having a dog (OR=8.4; 3.8) and eating grilled meat (OR=5.5; 2.1). Drinking unpasteurized milk was borderline significant in 1 model (OR=3.7). Eating sausage was protective (OR=0.05). Eating chicken was not a significant risk. Exposures such as eating grilled meat and drinking water from a lake or a river were more common in the warm months, a factor that may partly explain the observed seasonality. The authors suggest that differences between risk factors across studies may reflect geographical and age-specific differences in the sources of infection.     

Alcohol, marijuana, cocaine use, and relationship quality among HIV serodiscordant male couples

The association between substance use and relationship quality was explored in a sample of 117 serodiscordant male couples. Several measures of relationship quality were used including dyadic satisfaction, affection, commitment, sexual satisfaction, and domestic violence. Although frequency of use was assessed for several substances, only alcohol, marijuana, and cocaine were used frequently enough for statistical analyses. The highest frequency of use within the couple in the past 2 months as well as the discrepancy in the frequency of use between the 2 members of the couple were considered. Although daily substance use was relatively rare in this sample, alcohol use was reported by 79%, marijuana use by 35%, and cocaine use by 15% of the men. Domestic violence was not associated with any substance use variable. Marijuana use was generally not associated with relationship quality. Alcohol and cocaine use were moderately associated with several indicators of poorer relationship quality.     

Dementia and depressive symptoms as predictors of home help utilization among the oldest old: population-based study in an urban area of Sweden

OBJECTIVE: The objective of this article is to investigate predictors of public home help utilization, particularly mental health problems such as dementia and depressive symptoms. METHODS: A population-based sample of community-dwelling people aged 81-100 was interviewed and assessed with medical examinations (N = 502). RESULTS: Dementia increased the odds of receiving public home help among people residing alone. Among coresiding people, it increased the odds of receiving home help, but only among those who had extra residential care. Depressive symptoms decreased the odds of receiving home help among people with lower levels of education who lived alone. Depressive symptoms among highly educated people who lived alone and among coresiding people of any educational level were not related to receipt of home help. DISCUSSION: Improvement of screening activities for public home help needs of community-dwelling elders might allow better targeting of limited social resources to the most needy.     

Large iliac arteries: a high-risk group for endovascular aortic aneurysm repair.

PURPOSE: To examine if the presence of large iliac arteries is a potential risk factor for the development of a type Ib endoleak (iliac sealing zone) or need for iliac artery-related secondary intervention in patients undergoing endovascular abdominal aortic aneurysm repair. METHODS: The medical notes and all preoperative and postoperative plain abdominal radiographs and computer tomographic scans were reviewed for a consecutive series of 100 patients (89 men; mean age 75 years, range 56-91) with large iliac arteries (mean 19.7 mm, range 16-22) who had Zenith endovascular stent-grafts inserted for management of aortoiliac aneurysmal disease from January 1999 until September 2002. Endpoints were all-cause mortality, aneurysm-related death, endoleak, secondary intervention, secondary interventions, and stent-graft migration. RESULTS: Mean follow-up was 30.1+/-8.3 months; at the last follow-up, 30% of patients were dead, 3% were aneurysm-related. Seven (7%) patients developed a type Ib endoleak, with the remainder being type II (29%), type Ia (2%), type III (1%), and type V (endotension, 1%). Eight (27.5%) type II endoleaks persisted, with the remainder closing spontaneously with sac shrinkage. The iliac artery-related secondary intervention rate was 10%, and the overall secondary intervention rate was 16%. CONCLUSION: Iliac arteries between 16 and 22 mm in diameter may be treated with a cuff to the iliac limb with an expectation of 90% efficacy. Surveillance is required, with a high index of suspicion for type 1b endoleaks. Early secondary iliac intervention with extension to the external iliac artery is recommended if there is an increase in sac size after 6 months.