Table 2.

Targets and descriptions of 21 metal-conjugated antibodies for IMC analysis. Markers are subdivided into epithelial, endothelial, leukocyte, and prostate-specific panels for classification of cell type and origin.

Target	Description
ALDH1	ALDH1 belongs to the aldehyde dehydrogenase family. Nineteen ALDHs are present in humans, expressed in a variety of organelles, and having different substrate preferences. It is also expressed in the epithelium of many organs
Caspase 3	Caspase-3 is activated during the early stages of apoptosis. Caspase-3 is either partially or totally responsible for the proteolytic cleavage of many key proteins, such as the nuclear enzyme polymerase. Caspase-3 is widely distributed including high expression in cells of lymphoid origin and active caspase-3 is a marker for cells undergoing apoptosis
CD14	CD14 is a glycosylphosphatidylinositol (GPI)-linked membrane glycoprotein. CD14 is expressed at high levels on antigen presenting innate immune cells including monocytes and macrophages and at lower levels of granulocytes. It has also been reported to be expressed on some dendritic cell sub-populations
CD24	CD24 is expressed on the surface of B cells, granulocytes, follicular dendritic cells, and epithelial cells and may play a role in the regulation of B-cell proliferation and maturation
CD3	CD3 is a transmembrane subunit of the T Cell receptor complex. It is a member of the immunoglobulin superfamily that plays a role in antigen recognition, signal transduction, and T cell activation. CD3 is expressed by T lymphocytes (thymocytes) at the highest levels on mature cell types
CD31	CD31, also known as platelet endothelial cell adhesion molecule-1, is a type I transmembrane glycoprotein. It binds CD38 and plays a role in wound healing, angiogenesis, removing aged neutrophils and cellular migration in an inflammatory situation
CD38	CD38 is a transmembrane glycoprotein. It is expressed at variable levels across most human hematopoietic cells and in other tissues (i.e. Brain, muscle, and kidney). It is expressed at the highest levels on plasma cells (memory B cells) as well as activated T and B cells
CD44	CD44 is a cell surface glycoprotein. It is involved in a variety of cellular functions including: cell-to-cell interactions, adhesion, homing and migration, as well as being a receptor for hyaluronic acid. CD44 is expressed on a number of cell types including leukocytes, endothelial cells, hepatocytes, and mesenchymal cells and has been reported to be a marker for memory cell subsets
CD45	CD45 is a type I transmembrane glycoprotein. It is expressed on the plasma membrane of all hematopoietic cells, except mature red blood cells and platelets. Its intracellular domain is a tyrosine phosphatase that serves to regulate signal transduction in most hematopoietic cells.
CD45 RA	CD45A is a type I transmembrane glycoprotein. It is a specific splice variant of the transmembrane tyrosine phosphatase CD45. The CD45RA isoform is most highly expressed on resting/naïve T cells, B cells and monocytes. Like CD45, CD45A’s intracellular domain is a tyrosine phosphatase that servers to regulate signal transduction event—in particular, enhancing both T cell receptor and B cell receptor signalling
CD61	CD62 is a type I transmembrane glycoprotein. CD61 is a member of integrin family and is expressed on platelets and megakaryocytes playing a role in platelet activation and aggregation. CD61 in complex with CD51 has also been reported on osteoclasts, fibroblast, macrophages and some tumour cells
CD66	CD66a is a glycoprotein belonging to the immunoglobulin superfamily. It plays a role in multiple cellular activities such as differentiation and arrangement of tissue 3D structure, angiogenesis, apoptosis, tumour suppression, metastasis and the modulation of innate and adaptive immune responses. It can be found expressed on the surface of endothelial/epithelial cells, neutrophils and monocytes and can be induced on T cells, B cells, and CD16-negative NK cells
CD8a	CD8 is a type I membrane glycoprotein. CD8 is a member of the immunoglobulin superfamily found on the majority of thymocytes, a subset of PB T cells, and natural killer cells (which express almost exclusively CD8a homodimers). CD8 acts as a co-receptor with MHC class I-restricted T cell receptors in antigen recognition and T cell activation and has been shown to play a role in thymic differentiation
CK8/18	CytoKeratin 8 and 18 are intermediate filaments that provides mechanical support and serves variety of functions in epithelial cells. They are part of the cytoskeleton of the cell. CK8/18 is used by pathologist to evaluate pathogenesis of biopsy tissue in breast cancer
E-Cadherin	E-Cadherin (Epithelial cadherin) is a member of the cadherin superfamily. E-cadherin is a calcium-dependent, transmembrane cell–cell adnesion glycoprotein composed of 4 extracellular cadherin repeats and a highly conserved cytoplasmic tail region. It functions as cell adhesion molecule involved in development, bacterial, pathogenesis, and tumour invasion
EpCAM	Epithelial cell adhesion molecule (EpCAM) is a type I transmembrane protein. EpCAM functions as homotypic calcium-independent cell adhesion molecule and believed to be involved in carcinogenesis by inducing genes involved in cellular metabolism and proliferation. It is highly expressed in bone marrow, colon, lung, most epithelial cells and on carcinomas of gastrointestinal origin
HLA-DR	HLA-DR or human leukocyte antigen DR is an MHC class II cell surface receptor that is a cell surface glycoprotein. HLA-DR is expressed on B cells, activated T cells, monocytes/macrophages, dendritic cells, and other non-professional antigen presenting cells (APCs). HLA-DR is critical for efficient antigen presentation to CD4 + T cells
KI-67	Ki-67 protein is a cellular marker for proliferation. It is strictly associated with cell proliferation. During interphase, the Ki-67 antigen can exclusively detected within the cell nucleus, whereas in mitosis most of the protein is relocated to the surface of the chromosomes
PSA	Prostate-specific antigen (PSA) is a glycoprotein enzyme encoded in humans by the KLK3 gene. PSA is a member of the kallikrein-related peptidase family and is secreted by the epithelial cells of the prostate gland
PSMA	Human prostate-specific membrane antigen (PSMA) is a type II transmembrane zinc metallopeptidase. As a tumour marker in PCa, PSMA expression has been shown to correlate with disease progression
Vimentin	Vimentin are class-III intermediate filaments found in various non-epithelial cells, especially mesenchymal cells. It is highly expressed in fibroblasts, low in T- and B-lymphocytes. Vimentin has dynamic structural changes and spatial re-organization in response to extracellular stimuli help to coordinate various signalling pathways. Remodelling of Vimentin and other intermediate filaments is important during lymphocyte adhesion and migration through the endothelium

Epithelial Markers | Endothelial Markers | Leukocyte Markers | Prostate-specific Markers