| HHLA2

HERV-H LTR –associating 2 (HHLA2) is a recently discovered member of the B7-family of immune checkpoint molecules that is overexpressed in several types of cancer. HHLA2 was discovered in 1999 as a new member of the immunoglobulin (Ig) superfamily.It is constitutively expressed on the surface of human monocytes and is induced on B cells.HHLA2 binds to its putative receptor(s) on a variety of immune cells, including CD4 and CD8 T cells and antigen-presenting cells,[6] and it suppresses CD4 and CD8 T-cell function in the presence of T-cell receptor signaling.HHLA2 is reported to have both, co-inhibitory and co-stimulatory functions.
 

| 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)	20	10	5	2.5	1.25	0.625	0.312	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 HHLA2 spiked at three different levels in samples throughout the range of the assay was evaluated in various matrices.

 

Sample Type	Range(%)	Average Recovery(%)
Serum(n=8)	84-101	96
Plasma(n=8)	92-105	103
Cell Culture Supernates(n=8)	96-108	105

 

| Linearity

Samples were spiked with high concentrations of Human HHLA2 and diluted with Universal Diluent to produce samples with values within the range of the assay.

 

		Serum(n=4)	Plasma(n=4)	Cell Culture Supernates(n=4)
1 : 2	Range (%)	84-95	88-96	90-110
	Average (%)	91	93	96
1 : 4	Range (%)	89-103	87-108	105-115
	Average (%)	94	98	108