DESCRIPTION

Lysosome membrane protein II (LIMPII) is a member of the CD36 family. It is a lysosomal membrane protein that plays a role in the targeting of lysosomal enzymes and the regulation of lysosomal function. LIMPII is involved in the transport and processing of lysosomal enzymes, ensuring their proper delivery to lysosomes. Additionally, LIMPII has been identified as a receptor for glucocerebrosidase (GCase), an enzyme involved in the degradation of glucocerebroside. This receptor function is crucial for the proper functioning of lysosomes and the overall metabolic health of the cell.

PRINCIPLE OF THE ASSAY

Sandwich ELISA structure (Detection antibody labeled with HRP) A capture antibody is pre-coated onto the bottom of wells which binds to analyte of interest. A detection antibody labeled with HRP also binds to the analyte. TMB acts as the HRP substrate and the solution color will change from colorless to blue. A stop solution containing sulfuric acid turns solution yellow. The color intensity is proportional to the quantity of bound protein which is measurable at 450 nm with the correction wavelength set at 630 nm.

PRECISION

Intra-assay Precision (Precision within an assay) Three samples of known concentration were tested 8 times on one plate to assess intra-assay precision. Inter-assay Precision (Precision between assays) Three samples of known concentration were tested in 16 separate assays to assess inter-assay precision.

Intra-assay Precision

Sample	n	Mean (ng/mL)	SD	CV%
1	8	33.07	1.93	5.84
2	8	7.53	0.63	8.31
3	8	4.03	0.31	7.61

Inter-assay Precision

Sample	n	Mean (ng/mL)	SD	CV%
1	16	33.74	2.77	8.22
2	16	7.71	0.70	9.11
3	16	4.27	0.38	8.89

RECOVERY

The recovery of human/mouse LIMPII spiked to three different levels throughout the range of the assay in various matrices was evaluated.

Sample Type		Average% of Expected	Range (%)
Human plasma	1:4	99	81-126
Cell lysate	1:64	108	99-123
	1:128	98	97-101

LINEARITY

To assess the linearity of the assay, samples were diluted with the appropriate Sample Diluent to produce samples with values within the dynamic range of the assay. (The cell lysate was initially diluted 1:8. )

		Human plasma	Cell lysate
1:2	Average% of Expected	100	100
	Range (%)	-	-
1:4	Average% of Expected	108	106
	Range (%)	103-111	94-117
1:8	Average% of Expected	112	105
	Range (%)	106-117	92-118
1:16	Average% of Expected	120	104
	Range (%)	118-122	92-116

CALIBRATION

This immunoassay is calibrated against a highly purified recombinant human/mouse LIMPII produced at Sunlong Medical™.