Antigen positive cells

In order to label antigen-positive cells, treat PBMC prepared as in Section 3.2.1. with OK.T4 or OKT8 MAb of the appropriate specificity as follows ... 

After electroporation into Raji cells, CD4 antigen-positive cells are enriched by repeated cell sorting and plasmids are recovered in Escherichia coli. Individual plasmids are retransfected and clones that induce expression of CD4 antigen on the cell surface were identified. Positive clones are sequenced and their deduced amino acid sequences are examined for the presence of a signal peptide. If a stretch of hydrophobic amino acids is detected immediately... 

After three times of expansion and sorting, CD4 antigen-positive cells were enriched from 0.1% to 44.8% (about 450-fold), in our hands. 

Hayashi et al. (1996) tested the effects of a flavonoid in original-type anti-glomerular basement membrane antibody associated glomerulonephritis in male Sprague Dawley rats on upregulation of intracellular adhesion molecule expression and on increase in leukocyte function-associated antigen positive cells in nephritic glomeruli. 

Rotational stress caused a significant reduction in the number of CD3+ and CD4+ T-lymphocyte subsets in summer, whereas in winter the number of CD3+ subset was significantly increased the CD4+/CD8+ ratio and the number of NK 1.1 antigen positive cells were not significantly modified by rotational stress in both periods considered. The increase in metastasis formation by rotational stress thus appears to negatively correlate with the number of splenic CD3+ and CD4+ T-lymphocyte subsets (Perissin et al., 1998). 

Anti-CD20 MoAB linked to radioactive yttrium (Y ) murine version of the rituximab antibody monoclonal antibody to CD20 (a B-lymphocyte surface antigen)-positive cells binds complement and increases antibody dependent cellular cytotoxicity radioactive linkage delivers radiation dose directly to tumor cells to decrease damage to normal cells... 

Monoclonal antibody that reacts with CD20 (a B-lymphocyte surface antigen)-positive cells binds complement and increases antibody dependent ceiiuiar cytotoxicity... 

Proliferation markers show nuclear antigens that appear during one or more proliferative phases of the cell cycle. A labeling index (LI), also known as a proliferation index (PI), can be derived from them. i The LI of any of the proliferation antigens is the number of antigen-positive cells divided by the total number of cells in sampled microscopic areas of the tumor. Histologic grading of astrocytomas correlates with LI. ... 

Two days after electroporation cells are screened for T-antigen expression by indirect immunofluorescence. Efficiency is expressed as the percentage of T-antigen-positive cells. 

This antibody is raised against the protein-based CD3 antigen, present on the cell surface of most T-lymphocytes. I.v. administration of (unconjugated) antibody appears to block normal functioning of such T-cells and promote their clearance from the blood. However, upon cessation of antibody administration, CD3 positive cell numbers rapidly revert to normal values. Therefore, maintenance immunosuppressives (e.g. with cyclosporine) must subsequently be restored. 

Akdis M, Simon H-U, Weigl L, Kreyden 0, Blaser K, Akdis CA Skin homing (cutaneous lymphocyte-associated antigen-positive) CD8+ T cells respond to superantigen and contribute to eosinophilia and IgE production in atopic dermatitis. J Immunol 1999 163 466-475. 

Muromonab is a mouse monoclonal antibody against the CD3 receptor of T-lymphocytes. Its activity is based on inhibition of interactions between antigen-presenting cells and T-cells. By preventing antigen presentation it suppresses T-cell activation and proliferation. The indication for muromonab is the treatment of acute graft rejection after kidney, liver and hart transplantations. Its adverse effects consist of those symptoms that are initiated by the release of cytokines and lymphokines as a result of the reaction of muromonab with CD3 positive T-lymphocytes. These symptoms may vary from a mild flu-like syndrome to serious cardiac, pulmonale and neurological reactions. 

Cytokines have been under clinical investigation as adjuvants to vaccines, and IFNs and IL-2 have shown some positive effects in the response of human subjects to hepatitis vaccine. IL-12 and GM-CSF have also shown adjuvant effects with vaccines. GM-CSF is of particular interest because it promotes recruitment of professional antigen-presenting cells such as the dendritic cells required for priming naive antigen-specific T-lymphocyte responses. There are some claims that GM-CSF can itself stimulate an antitumor immune response, resulting in tumor regression in melanoma and prostate cancer. 

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