Antibody Screening (antibody + screening)

Distribution by Scientific Domains


Selected Abstracts


HLA antibody testing: a tool to facilitate not to prevent organ transplantation

INTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4-5 2008
Frans H. J. Claas
Summary The introduction of very sensitive HLA antibody screening assays has destroyed the old dogma that pre-existence of donor specific HLA antibodies in the patient is a contra-indication for transplantation. The challenge is now to reach consensus on the parameters which predict the clinical relevance of donor specific HLA antibodies. Antibody screening assays should not only be used to prevent transplantation of patients with donor specific antibodies but also to facilitate transplantation of highly sensitized patients, both by defining acceptable HLA mismatches and non-detrimental donor specific HLA antibodies. [source]


Flow cytometry antibody screening using pooled red cells,

CYTOMETRY, Issue 2 2010
Dong Il Won
Abstract Background: For red cell alloantibody screening, the column agglutination technique (CAT) is used extensively, and flow cytometry (FC) screening has recently been demonstrated to be accurate, rapid, and cost effective. We attempted to determine whether the high sensitivity of FC allows pooling of screening red cells, which is generally not an acceptable technique in CAT. Methods: For FC screening, a commercial two-cell screening panel was utilized for the preparation of individual cells (CSi), as well as pooled cells diluted 1 in 2 (CSp), and 1 in 3 (CS1/3). Another panel was pooled from 120 randomly selected group O donors (RSp). Results: Comparing the endpoint titrations of serial dilutions, CS1/3 was found to be one dilution, on the average, less sensitive than CSi. In 33 CAT-positive patient samples, the sensitivities of CSi and CSp did not differ significantly without polyethylene glycol (PEG) (30/33, 26/33, respectively, P = 0.125), although they did differ significantly with PEG (32/33, 25/33, respectively, P = 0.016). The percentages of reactive cells among the total cells from RSp were roughly proportional to the relevant antigen frequencies of the local donors. Conclusions: A trend toward reduced sensitivity was observed using pooled red cells, even via FC. Pooled cells from randomly selected group O donors may be employed as another method by which the characteristics of known antibodies might be assessed. © 2009 Clinical Cytometry Society [source]


The effect of biopsy-positive silent coeliac disease and treatment with a gluten-free diet on growth and glycaemic control in children with Type 1 diabetes

DIABETIC MEDICINE, Issue 12 2009
S. Sun
Abstract Objective, To determine the effect of coeliac disease and treatment with a gluten-free diet on growth and glycaemic control in asymptomatic children with Type 1 diabetes. Methods, Data were compared in children with coeliac disease diagnosed by annual antibody screening and jejunal biopsy and treated with a gluten-free diet (n = 49) against individuals who were antibody negative (n = 49) matched for age, sex and duration of diabetes. Results, No differences in growth were observed. In the years prior to diagnosis of coeliac disease, mean glycated haemoglobin (HbA1c) was lower in cases compared with control subjects [8.3 ± 1.1% vs. 8.7 ± 0.9%, P = 0.02 (mean ± sd)]. In cases, HbA1c deteriorated 12 months from the start of a gluten-free diet to levels similar to control subjects (8.9 ± 1.5% vs. 8.8 ± 1.5%, P -value for analysis of variance = 0.9). In regression analysis, the diagnosis of coeliac disease and start of a gluten-free diet was associated with a rise in HbA1c in the first year of treatment [odds ratio 1.56 (95% confidence intervals 1.16,2.10), P = 0.003] after adjusting for insulin dose and regimen and other variables. Conclusions, In children with Type 1 diabetes, lower HbA1c prior to diagnosis of silent coeliac disease rises following treatment with a gluten-free diet to levels similar to those without coeliac disease. Although unproven, these observations may relate to abnormalities at the small bowel mucosa before the appearance of circulating coeliac antibodies. [source]


HLA antibody testing: a tool to facilitate not to prevent organ transplantation

INTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4-5 2008
Frans H. J. Claas
Summary The introduction of very sensitive HLA antibody screening assays has destroyed the old dogma that pre-existence of donor specific HLA antibodies in the patient is a contra-indication for transplantation. The challenge is now to reach consensus on the parameters which predict the clinical relevance of donor specific HLA antibodies. Antibody screening assays should not only be used to prevent transplantation of patients with donor specific antibodies but also to facilitate transplantation of highly sensitized patients, both by defining acceptable HLA mismatches and non-detrimental donor specific HLA antibodies. [source]


Role of enzyme-treated cells in RBC antibody screening using the gel test: a study of anti-RH1, -RH2, and -RH3 antibodies

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2007
Jocelyne Conne
Abstract The role of enzyme-treated cells (ETCs) in red blood cell (RBC) antibody screening has been the subject of controversy, and its place in the clinical routine remains to be determined. In this work, plasma samples containing anti-RH1 (anti-D; N = 10), anti-RH2 (anti-C; N = 10), or anti-RH3 (anti-E; N = 10) antibodies were studied. The samples were diluted in nonbuffered or buffered normal saline, as well as in a pool of AB plasma samples. Titers and scores were determined by means of the gel test, using the indirect antiglobulin test (IAT) as well as ETCs, with R0r, r,r, or r,r test cells. Our results showed that compared to the IAT, ETCs allowed a clearer detection of anti-RH2 and anti-RH3, but not of anti-RH1 antibodies. Based on our study, it is not clear whether the ETC phase of the gel test should be maintained for RBC antibody screening. J. Clin. Lab. Anal. 21:61,66, 2007. © 2007 Wiley-Liss, Inc. [source]


Pretransplant HLA Antibodies Are Associated with Reduced Graft Survival After Clinical Islet Transplantation

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2007
P. M. Campbell
Despite significant improvements in islet transplantation, long-term graft function is still not optimal. It is likely that both immune and nonimmune factors are involved in the deterioration of islet function over time. Historically, the pretransplant T-cell crossmatch and antibody screening were done by anti-human globulin,complement-dependent cytotoxicity (AHG-CDC). Class II antibodies were not evaluated. In 2003, we introduced solid-phase antibody screening using flow-based beads and flow crossmatching. We were interested to know whether pretransplant human leukocyte antigen (HLA) antibodies or a positive flow crossmatch impacted islet function post-transplant. A total of 152 islet transplants was performed in 81 patients. Islet function was determined by a positive C-peptide. Results were analyzed by procedure. Class I and class II panel reactive antibody (PRA) > 15% and donor-specific antibodies (DSA) were associated with a reduced C-peptide survival (p < 0.0001 and p < 0.0001, respectively). A positive T- and or B-cell crossmatch alone was not. Pretransplant HLA antibodies detectable by flow beads are associated with reduced graft survival. This suggests that the sirolimus and low-dose tacrolimus-based immunosuppression may not control the alloimmune response in this presensitized population and individuals with a PRA > 15% may require more aggressive inductive and maintenance immunosuppression, or represent a group that may not benefit from islet transplantation. [source]