Conclusions
The monomeric form is the predominant form secreted by tubular epithelial cells, and the dimeric form is the predominant form secreted by neutrophils. The development of molecular form-specific assays for HNL/NGAL may be a means to identify the origin of HNL/NGAL in urine and construct more specific tools for the diagnosis of AKI.
Results
The major molecular form of HNL/NGAL secreted by neutrophils is dimeric, whereas the major form secreted by HK-2 cells is monomeric. This was reflected by a predominance of the monomeric form in urine from patients with AKI and the dimeric form in patients with UTIs. The epitope specificities of the antibody used in the ELISAs had a profound effect on assay performance and paralleled differences of the antibodies to identify the different forms of urine HNL/NGAL. Conclusions: The monomeric form is the predominant form secreted by tubular epithelial cells, and the dimeric form is the predominant form secreted by neutrophils. The development of molecular form-specific assays for HNL/NGAL may be a means to identify the origin of HNL/NGAL in urine and construct more specific tools for the diagnosis of AKI.