| XBP1

X-Box Binding Protein 1 is a transcription factor that regulates the expression of genes important to the proper functioning of the immune system and in the cellular stress response.XBP1 expression is controlled by the cytokine IL-4 and the antibody IGHM.XBP1 in turn controls the expression of IL-6 which promotes plasma cell growth and of immunoglobulins in B lymphocytes.XBP1 is required for eosinophil differentiation. Eosinophils lacking XBP1 exhibit defects in granule proteins.XBP1 acts to regulate endothelial cell proliferation through growth factor pathways,leading to angiogenesis. Additionally, XBP1 protects endothelial cells from oxidative stress by interacting with HDAC3.
 

| Typical data

As the OD values of the standard curve may vary according to the conditions of the actual assay performance (e.g. operator, pipetting technique, wash technique or temperature effects), the operator should establish a standard curve for each test. Typical standard curve and data are provided below for reference only.

 

Concentration (ng/mL)	10	5	2.5	1.25	0.625	0.312	0.156	0
OD	2.22	1.56	0.92	0.63	0.42	0.25	0.18	0.08
Corrected OD	2.14	1.48	0.84	0.55	0.34	0.17	0.1	-

 

| Repeatability

Intra-assay Precision (Precision within an assay)：CV% < 10%; Inter-assay Precision (Precision between assays)：CV% < 10%
 

| Recovery

The recovery of Human XBP1 spiked at three different levels in samples throughout the range of the assay was evaluated in various matrices.

 

Sample Type	Range(%)	Average Recovery(%)
Tissue Homogenates(n=8)	84-101	96
Cell Lysates(n=8)	92-105	102

 

| Linearity

Samples were spiked with high concentrations of Human XBP1 and diluted with Universal Diluent to produce samples with values within the range of the assay.

 

		Tissue Homogenates(n=4)	Cell Lysates(n=4)
1 : 2	Range (%)	84-95	85-96
	Average (%)	91	93
1 : 4	Range (%)	89-103	87-108
	Average (%)	94	95