Human Hashtag 3 Antibody from BIOLEGEND

TotalSeq™ anti-human Hashtag reagents are designed to label most human cells, using a combination of two clones that recognize CD298 and β2 microglobulin, respectively. The antibodies are conjugated to the same oligonucleotide, pre-mixed to be used following an optimized protocol similar to the CITE-seq workflow.

β2-microglobulin (β2M) is a 12 kD nonpolymorphic Ig like protein. It is a non-membrane-anchored glycoprotein and is noncovalently associated with 39-44 kD polymorphic heavy chains of MHC class I molecules to form HLA class I antigen complex. In association with HLA class I, β2M is expressed on all leukocytes, platelets, endothelial cells, and epithelial cells. β2M plays an essential role both in governing MHC class I molecules stability and in promoting antigen binding and presenting the antigen to CD3/TCR complex of CD8⁺ T cells.

CD298 or the β3 Na⁺/K⁺ ATPase, is a 42 kD type II transmembrane protein, also known as ATP1B3. An integral plasma membrane protein, Na⁺/K⁺ ATPase is composed of one α and one β subunits. Four isoforms of the α and three isoforms of the β subunits have been reported. Na⁺/K⁺ ATPase couples ATP hydrolysis to the development of an ionic gradient by pumping Na⁺ and K⁺ ions in opposite directions across the cell plasma membrane. It has broad tissue distribution, including all leukocytes and many other tissues.