The serum of a normal human has a low concentration of these proteins but when the body is activated due to disease, their concentrations increase drastically, and therefore, monitoring of cD levels helps in disease management.<\/li>\n<\/ul>\n\n\n\nFor example;<\/strong><\/p>\n\n\n\n\n- CD54, also known as intercellular adhesion molecule-1 (ICAM-1), is a protein that is an important early marker of immune activation and response. It is a ligand for the lymphocyte function-associated antigen-1 (LFA-1) found on lymphocytes, monocytes, and neutrophils. The CD54\/LFA-1 interaction is important in T-cell\u2013antigen-specific responses and lymphocyte emigration into inflammatory sites. CD54 also is found on mucosal epithelial cells and erythrocytes. Recent evidence suggests CD54 is the cellular receptor for the human rhinovirus and Plasmodium falciparum-infected<\/em> erythrocytes. The circulation of CD54 relates to the progress and prognosis of skin cancer metastatic melanoma,<\/li>\n\n\n\n
- CD23 which is a B-cell growth factor, is a protein found on the surface of IgM-bearing B cells, eosinophils, macrophages, and platelets. Soluble CD23 is a B-cell growth factor and upregulates IgE synthesis in conjunction with interleukin-4 released from T cells. When its levels are elevated, it is associated with chronic lymphocytic leukemia.<\/li>\n\n\n\n
- CD35 is a glycoprotein that is present on erythrocytes, Poly MorphoNuclear cells (PMNs), monocytes, all B-cells, and some T cells, mast cells, and in the soluble form in the plasma. It is the receptor for complement C3b\/C4b. The functions of CD35 include binding of immune complexes on erythrocytes that bear C3b or C4b and promote their clearance from the circulation, CD35 augments the maturation of B-cells into antibody-secreting cells, aiding leukocytes in binding and phagocytosing C3b- or C4bcoated objects. CD35 is also a potential agent for suppression of complement-dependent tissue injury in autoimmune inflammatory disease.<\/li>\n\n\n\n
- The CD8 molecule is a polypeptide found on the surface of cytotoxic T cells. It is a molecule that participates in the interaction of class I
MHC found on target cells. Elevated CD8 is found in children with lymphoid malignancies and in HIV-infected individuals<\/li>\n\n\n\n - CD4 is a glycoprotein that is found on T-cells associated with helper\/inducer regulatory functions and also reduces the degree on monocyte and macrophages. It is a cell adhesion molecule that has a great affinity for class II MHC.<\/li>\n\n\n\n
- The CD2 is a glycoprotein present on T cells, thymocytes, and NK cells. It functions as an intercellular adhesion molecule and binds
to the human leukocyte function-associated antigen-3 or LFA-3 (CD58). CD2 may be involved in the attachment of TH cells to antigen-presenting cells and cytotoxic T cells to target cells, and in other cellular interactions. It also is a signal-transducing molecule and may help stimulate T cells to proliferate and secrete cytokines.<\/li>\n<\/ul>\n\n\n\n