DESCRIPTION

IL-4Rα (IL-4 receptor alpha chain, also known as CD124) is an important member of the cytokine receptor family, primarily involved in immune responses and cellular signal transduction. It is a single-pass transmembrane protein that binds to IL-4 and IL13 through its extracellular domain, activating the JAK/STAT signaling pathway to regulate cell proliferation, differentiation, and function. IL-4Rα is expressed in various immune cells (such as T cells, B cells, and macrophages) and is crucial for Th2 cellmediated immune responses. In allergic diseases (such as asthma and atopic dermatitis), IL-4Rα plays a key role by promoting the production of IgE antibodies and the activation of inflammatory cells. Additionally, IL-4Rα is involved in the regulation of autoimmune diseases and the tumor microenvironment. Studying the signaling pathways and functional mechanisms of IL-4Rα helps to develop new therapeutic strategies for allergies, inflammation, and cancer.

PRINCIPLE OF THE ASSAY

An anti-tag antibody is pre-coated onto the bottom of wells. After adding antigen or samples, Tagged-Capture antibody and HRP-conjugated detection antibody, a sandwich complex is formed in the solution. TMB acts as a HRP substrate, and the solution color will change from colorless to blue. A stop solution containing sulfuric acid turns the 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 (pg/mL)	SD	CV%
1	8	813.9	17.9	2.2
2	8	212.5	2.7	1.3
3	8	114.4	1.4	1.2

Inter-assay Precision

Sample	n	Mean (pg/mL)	SD	CV%
1	16	805.9	20.6	2.6
2	16	212.9	3.3	1.6
3	16	114.9	2.3	2.0

RECOVERY

The recovery of mouse IL-4 R alpha/CD124 spiked to three different levels throughout the range of the assay in various matrices was evaluated.

Sample Type		Average% of Expected	Range (%)
Mouse serum	1:640	96	81-112
Tissue lysate	1:16	98	88-113

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 mouse serum was initially diluted 1:40.)

		Mouse serum(Sample Diluent PT 4B1)	Tissue lysate(Sample Diluent PT 5)
1:2	Average% of Expected	100	100
	Range (%)	-	-
1:4	Average% of Expected	101	94
	Range (%)	91-111	92-95
1:8	Average% of Expected	105	92
	Range (%)	99-112	86-98
1:16	Average% of Expected	113	88
	Range (%)	105-121	79-97

CALIBRATION

This immunoassay is calibrated against a highly purified recombinant human Mouse IL-4 R alpha/CD124 One-Step ELISA Kit produced at Sunlong Medical™.