Murdoch University Research Repository

Welcome to the Murdoch University Research Repository

The Murdoch University Research Repository is an open access digital collection of research
created by Murdoch University staff, researchers and postgraduate students.

Learn more

A rapid and sensitive flow-based screening test for detection of HLA-B57 to avoid abacavir hypersensitivity

Kostenko, L., Lucas, A., Kjer-Nielsen, L., Foley, B., Nicholson, I., Tait, B., Holdsworth, R., Rossjohn, J., Mallal, S. and McCluskey, J. (2007) A rapid and sensitive flow-based screening test for detection of HLA-B57 to avoid abacavir hypersensitivity. In: 4th International AIDS Conference on HIV Pathogenesis, Treatment and Prevention, 22 - 25 July, Sydney, Australia.

Abstract

Objectives: About 5-10% of HIV-1 patients treated with Abacavir develop a hypersensitivity reaction characterised by systemic symptoms which resolve when treatment is discontinued. The presence of HLA-B*5701 is a strong predictor of Abacavir hypersensitivity and pre-screening of patients for HLA-B*5701 reduces the incidence of Abacavir hypersensitivity. However, current DNA-based methods of HLA-B*57 typing (SBT) are slow and expensive. Screening by Flow cytometry offers logistical advantages when combined with the routine CD4 T cell enumeration and potentially provides a 1-2 day turnaround.

Methods: A mAb that reacts with members of the HLA-B57 and B58 serological group (anti-HLA-B17) was generated and optimised for flow cytometry-based assay.

Results: Screening of ~70 consecutive normal blood donors with known HLA genotype and staining of Labscreen beads coated with disparate HLA class I allotypes verified the mAb, 3E12, has 100% sensitivity for HLA-B57/B58. A pilot exchange program confirmed the utility of the mAb in a single-step flow cytometry-based assay, using whole blood and either fresh or frozen/thawed PBMCs. The mAb was used to screen frozen PBMCs from 601 HIV-infected patients participating in the PREDICT-1 clinical trial and compared to sequence-based HLA typing . The sensitivity of the mAb typing was again 100%.

Conclusions: Our findings suggest that the 3E12 mAb provides a basis for a rapid Flow-based screening test to identify patients with HLA-B57/B58 prior to treatment with abacavir. Given the combined phenotype frequency of HLA-B57 and B58 in most populations is 5-8%, screening with mAb 3E12 would allow >90% of patients to start therapy without further HLA-testing. Patients who screened positive for the mAb would be referred for DNA-based HLA-genotyping. The screen also offers the possibility of rapid and simple point-of-care test adaptable for developing nations.

Item Type: Conference Item
Murdoch Affiliation(s): Institute for Immunology and Infectious Diseases
Conference Website: http://www.iasociety.org/
URI: http://researchrepository.murdoch.edu.au/id/eprint/15739
Item Control Page Item Control Page