Monoclonal antibodies immunization

For the production of monoclonal antibodies, immunization may be achieved either in vivo (most common) or in vitro. Immunization in culture and subsequent production of monoclonal antibodies may carry several important advantages (reviewed by Reading, 1982) ... 

Cytokines. Figure 1 Inhibition of cytokine synthesis during activation of the specific immune system. The monoclonal antibodies Muromonab and Basiliximab are specific for the CD3 complex of the T-cell receptor, and for the IL-2 receptor on lymphocytes, respectively. Cyclosporin and Tacrolimus inhibit activation of cytoplasmic NF-AT, a transcription factor essential for activation of the IL-2 gene ( NFAT Family of Transcription Factors). Sirolimus interferes with mTOR signaling and inhibits IL-2 dependent proliferation. Red pharmaka, blue target proteins. 

Two main strategies are presently used to suppress immune responses (summarized in Fig. 3). The first focuses on cytokines, the central mediators of the immune system. Efficient inhibition of cytokine production can be achieved by glucocorticoids. Specific anticytokine strategies include the use of monoclonal antibodies, soluble receptors, or receptor constructs. 

Immune Defense. Figure 3 Drugs involved in suppressing innate and adaptive immune response. Abbreviations mob monoclonal antibody, TCR T-cell antigen receptor, IL-2 interleukin-2, R receptor, CD cluster of differentiation. 

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]. 

Commercially available dtugs used for therapeutic therapy comprise up to date mainly injectable monoclonal antibodies like Infliximab (Remicade ) and Adalimumab (Humira ) or TNF-receptor derivatives like Etanercept (Enbrel ) (Fig. 3). One possible way of action of these reagents is the neutralization of TNF, thereby blocking its inflammatory effects and dampening (auto)immune responses [3, 4]. 

Humanized Monoclonal Antibodies Humoral Immunity HVA Ca2+ Channels Hybridization... 

Miyake et al reported an ELISA method for the determination of pesticide residues in the aquatic environment. The polyclonal antibody and three monoclonal antibodies of acifluorfen were prepared by immunization of rabbits and mice with acifluorfen-bovine serum albumin conjugates. The polyclonal antibody reacted with acifluorfen at concentrations of 1.5-800 mg L , while the monoclonal antibodies reacted with acifluorfen at concentrations of 1.5-144 mg L . Among three monoclonal antibodies, AF 75-144 reacted with chlornitrofen, which did not react with the other two antibodies. It seems that the ELISA method is effective for the determination of herbicide residues in the aquatic environment. 

Figure 13 Structures of haptens used for immunizing and coating antigens in a monoclonal antibody-based immunoassay for diuron. A sensitive assay was developed using coating hapten I that had the handle in a position different from the immunogen hapten. When the oxygen in the urea moiety of hapten I was replaced with a sulfur (hapten 11), increasing the heterology, even greater sensitivity was achieved...

The cell surface contains antigens, which are referred to as CD, which stands for cluster of differentiation. The antibodies are produced against a specific antigen. When administered, usually by an intravenous injection, the antibody binds to the antigen, which may trigger the immune system to result in cell death through complement-mediated cellular toxicity, or the antigen-antibody cell complex may be internalized to the cancer cell, which results in cell death. Monoclonal antibodies also may carry radioactivity, sometimes referred to as hot antibodies, and may be referred to as radioimmunotherapy, so the radioactivity is delivered to the cancer cell. Antibodies that contain no radioactivity are referred to as cold antibodies. 

Administration of Tyv-specific monoclonal antibodies to rat pups already infected with intestinal larvae causes larvae in the epithelium to be expelled (Carlisle et al, 1990). Only the LI stage is susceptible to expulsion once the larva has moulted to L2 it resists the effects of the antibodies (Carlisle et al, 1990). Expulsive immunity is transferred by three IgG isotypes, F(ab )2 fragments, as well as IgM (Carlisle et al., 1991a). These findings argue against a role for Fc-mediated effector functions and imply that antibodies against Tyv can disturb the larva s niche in a direct fashion. 

Parasitism by T. spiralis has been a subject of scientific interest for over 150 years. Recently, considerable attention has been paid to the parasite by immunologists interested in immunity to nematodes in general, and mucosal immunity in particular. It has been shown that glycan-specific antibodies are highly effective mediators of host defence against intestinal 7. spiralis infection. Protective monoclonal antibodies have been used to elucidate mechanisms of worm expulsion, as well as to identify molecules that the parasite uses to create its niche. In the future, detailed characterization of these molecules and their functions should afford additional insights into parasitism by Trichinella spiralis, and possibly also by other types of pathogen. 

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