Antibody activities determination

Rituximab is a monoclonal antibody to the CD20 receptor expressed on the surface of B lymphocytes the presence of the antibody is determined during flow cytometry of the tumor cells. Cell death results from antibody-dependent cellular cytotoxicity. The pharmacokinetics of rituximab are best described by a two-compartment model, with a terminal half-life of 76 hours after the first infusion and a terminal half-life of 205 hours after the fourth dose.36 Rituximab has shown clinical activity in the treatment of B-cell lymphomas that are CD20+. Side effects include hypersensitivity reactions, hypotension, fevers, chills, rash, headache, and mild nausea and vomiting. 

Pressman, D., and Keighley, G. (1948) The zone of activity of antibodies as determined by the use of radioactive tracers. The zone of activity of nephritoxic antikidney serum. /. Immunol 59, 141-146. 

The surface activation time of the polymer required for maximum site activity for binding antibodies was determined by evaluating the fluorescence intensity of a series of probes incubated in inorganic acids at different times. Knowledge of the surface activation time is necessary to obtain maximum activation, thus allowing maximum antibody immobilization on the probe. Consequently, lower detection limits may be achieved. 

In general, four factors help to determine the sensitivity of the sandwich ELISA. These factors are (1) the number of molecules of the first antibody that are bound to tbe solid phase (2) the avidity of the first antibody for the antigen (3) the avidity of the second antibody for the antigen (4) the specific activity of the second antibody. By diluting or concentrating the antibody solution, the amount of capture antibody that is bound to the solid phase can be adjusted. In contrast, tbe avidity of the antibodies for the antigen can be altered only by substituting other antibodies. The specific activity of the second antibody is determined by the number and type of labeled moieties it contains. 

EMSA assays can also be exploited to measure STAT nuclear localization, which is, similar to NFkB localization, a measure of STAT activity. Determination of JAK phosphorylation is carried out by immunoprecipitation of the JAK proteins from cell lysates, followed by SDS-PAGE electrophoresis, immunoblotting with antiphosphotyrosine antibody and JAK-specific antibody re-probing [99]. 

There are five classes of immunoglobulins that can be distinguished by antigenic determinants on the heavy chains (see later), namely, IgM, IgG, IgA, IgD, and IgE. Antibody activity has been demonstrated in each of the classes. The molecular organization of immunoglobulins is based on a four-chain, unitary structure con-... 

Bergman, R., Malkin, L., Sabo, E., and Kemer, H. 2001. MIB-1 monoclonal antibody to determine proliferative activity of Ki-67 antigen as an adjunct to the histopathologic differential diagnosis of spitz nevi. J. Am. Acad. Dermatol. 44 500—504. 

In all the experiments reported here, antibody activities were determined by antibody-mediated complement-dependent release of trapped narker from liposomes (3,10). The liposomes contained dimyristoylphosphatidylcholine (except where indicated), choles-... 

MAbs produced by immunizing with receptor transfectants must be screened by flow cytometry—first against receptor transfectants to select for immunore-active MAbs to the immunogen and then against the parental cell line to eliminate those immunoreactive antibodies recognizing determinants other than the transfected receptor. Mice will make antibodies to cell surface determinants other than the receptor of interest even when a syngeneic mouse cell line is used as the parental line for transfectants. 

Using the total protein concentrations (in milligrams per milliliter) for each primary antibody sample determined on Day 1, calculate the specific activity of the four rabbit serum samples using the following equation ... 

Figure 6 shows a typical calibration curve obtained for the inhibition of binding of a urease-cAMP conjugate to anti-cAMP antibody as determined by the ammonia electrode. One hundred percent of activity refers to blank tubes, which had rates of 11-12 mV/min in the absence of cAMP. Selectivity of the assay over structurally similar cGMP is also shown in Fig. 6. It takes approximately 1000 times more cGMP than...

Therapy becomes problematic when antibodies and markers of HCV infection are evident. It is imperative to complete the unambiguous identification of HCV antibodies by determination of HCV RNA. (The positivity of HCV antibodies may well be a methodologically related false-positive result.). If HCV RNA is detected, i. e. in florid HCV infection, interferon therapy (or a combination with ribavirin) should be considered. This antiviral therapy may be indicated despite positivity of LKM 1 following critical evaluation and close-meshed controls. There is a possibility of AIH activation under antiviral therapy. In this case, INF therapy has to be stopped as quickly as possible. It is not currently known whether this risk can be avoided by simultaneous administration of low-dose prednisolone. The same problem arises in the (very rare) combination of AIH with coexistent florid HBV infection. 

Increased values of AH and AS for the mAh 4-4-20/monofluoresceinated peptide complexes relative to the mAh 4-4-20/fluorescein complex decay were interpreted as resulting from inclusion of the carrier peptides. Increased enthalpic contributions may have resulted from actual binding interactions between the surface accessible complementarity determining regions (CDRs) surrounding the mouth of the antibody active site and the amino acids of the peptides. Whitlow etal. (15) reported that a significant percentage of the amino acids that compose the mAb 4-4-20 CDRs were solvent accessible when fluorescein was in the active site. The increased values for AH also may have been due to differences in hydration of the antibody complexes. 

Production of Monoclonal Anti-Picloram Antibody, Ten 11-week-old mice were injected intraperitoneally with a total volume of 250 uL of a 1 1 (v/v) mixture of 70 ug of immunogen dissolved in PBS and Freund s complete adjuvant (16). Secondary inoculations were given three and eleven weeks after the initial immunization. One week following each secondary inoculation, the mice were bled from the retro-orbital plexus and the anti-picloram serum antibody titer was determined using the RIA procedure described by Hall et al. (1 ). A serum sample was considered positive for anti-picloram antibody activity if binding of the picloram radiolabel was more than twice the level of non-specific binding. 

Non-competitive solid-phase enzyme immunoassays based on the avidin-biotin system for the determination of antibody activity in sera ... 

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