Monoclonal antibodies testing

I direct fluorescent monoclonal antibody test. Given the fact that most women are asymptomatic, an annual screening or physical is necessary, as early detection may reduce rates of transmission. 

Hospital and commercial diagnostic testing laboratories rely on monoclonal antibody tests to measure the amounts of specific proteins, hormones, or drugs in blood. Monoclonal antibodies tagged to fluorescent dyes are also used with lasers to determine the kind of tumor a patient has, to track the number of tumor cells, and to monitor the level of immune system cells. The CD4 count test, important to patients with HIV infection, uses monoclonal antibodies and a laser-driven device that checks cell by cell for the CD4 protein, the marker for the critical immune system cell. The same technology and a set of antibodies to immune system cell proteins are used to diagnose children suspected of having inherited an immune system deficiency. 

Tissue cross-reactivity studies, although burdensome, provide a rational in vitro assay to determine the range and intensity of distribution of potential epitopes reactive with a monoclonal antibody test article prior to its administration to humans. In addition, cross-reactivity studies provide a useful tool to identify animal species for safety assessment. The cross-reactivity profiles of different species can be compared to the profiles obtained in human tissues. The predictive value of the assay lies in incorporating the characteristics of the monoclonal antibody (isotype, subtype, and other molecular modifications) with the biological activity of the molecule itself, and the potential in vivo distribution of it. 

Homologous proteins and/or systems Testing purified animal protein in the same species or, for monoclonal antibodies, testing an antibody directed against the receptor in the animal. Data should be interpreted with caution as the biological properties of the animal protein may differ from those of the human protein. 

Commercial use of cell and tissue culture continues to expand. Improvement of organisms through recombinant nucleic acid techniques has become commonplace. Formerly, a few laboratories were well ahead of most others, but now the methods have been perfected for routine use. Another technique that is widely practiced is culturing of cells that excrete high concentrations of just one antibody protein. The specificity of antibodies and antigens is exploited in medical testing procedures using these pure monoclonal antibodies. 

The first mouse monoclonal antibody specific for human CD3 was produced in 1979 and named orthoclone OKT3. Aside from its use in the laboratory, OKT3 became the first anti-CD3 antibody to be utilized in transplantation medicine, but its wider application was hampered by its immunogenic and mitogenic properties (reviewed in [6]). Consequently, humanized and engineered anti-CD3 antibodies were developed to circumvent these limitations (Table 1). Since T cells and the TCR are involved in many immunological diseases, it is not surprising that the application of CD3 antibodies is not restricted to the field of transplantation. For example, CD3 antibodies are tested in clinical studies of diseases such as autoimmune diabetes (type 1 diabetes), immune-mediated inflammatory arthritis and inflammatory bowel disease [7]. 

Davio et al. (43) report efforts to obtain monoclonal antibodies (mAbs) to STX. Because STX is a small molecule of approximately 300 daltons, well below the size necessary for immunogenicity, a carrier molecule must be conjugated to the hapten (STX). This technique must minimize alterations of the antigenic form. For the anti-STX antibodies tested to date, the ratios of immunoassay response factor to pharmacological potency for various STX derivatives differ substantially, the immunoassay being virtually unresponsive to some of the common natural derivatives (44). 

The next hypothesis tested was whether combining monoclonal antibody therapy with chemotherapy could increase... 

M. L. Roy, M. J. Pikal, E. C. Rickard, and A. Maloney, The effects of formulation and moisture on the stability of a freeze-dried monoclonal antibody-vinca conjugate A test of the WLF glass transition theory Dev. Biol. Standards, 74, 323 (1991). 

The most common BTA test is an immunoassay-based assay that uses monoclonal antibodies to detect the presence of bladder tumor-associated antigen in urine. In clinical studies, the BTA test was compared with cytoscopy-voided urine for the detection of recurrent bladder cancer. The sensitivity of BTA appeared su-... 

Figure 7.1. Protein expression mapping using an antibody array. The antibody array consists of monoclonal antibodies specific for a set of proteins in the organism of interest gridded onto a filter. To determine if a protein is expressed under the conditions being tested, a crude lysate is obtained and the proteins within the lysate are labeled with a fluorescent tag. The lysate is applied to the filter and the proteins are allowed to bind to the relevant antibody. Bound proteins are visualized via the fluorescent tag.

The limitations of ELISA methods include the specificity of antibodies, the concentrations of primary antibody and antigen, and the type of reaction solution. Nonspecific binding of either of the antibodies to related antigens, unrelated proteins of other bacteria, or even the microtiter plate may lead to false positive reactions.49,52 57 Use of a monoclonal antibody may decrease crossreactivity with other antigens. For detection of low numbers of bacteria, as in drinking water, the sample may be filtered to concentrate the cells or cultured in a selective broth until it reaches the minimum detection limit for ELISA.49,58 Commercial test kits using dipsticks, immunoblots, and sandwich ELISA methods have been developed for the identification of pathogenic bacteria.58,59... 

Wan WH, Fortuna MB, Furmanski P. A rapid and efficient method for testing immunohistochemical reactivity of monoclonal antibodies against multiple tissue samples simultaneously. I. Immunol. Methods 1987 103 121-129. 

---