Antibody immunization schedule

Most vaccines require two or three primary immunizations, followed by a booster for optimum immune response. If one injection of the immunization schedule is missed, it leads to manifold loss of effective antibody titers. According to WHO statistics, more than 30% of the patients do not return for the next injection at each period of the immunization schedule. The effect of noncompliance is most severe in third world countries, where more than a million children die each year from vaccine-preventable diseases. 

The immunization schedule used will vary with the antigen and the characteristics of the antibody required. For a novel antigen, it is common to employ previously reported procedures successfully used with similar antigens and to adapt these... 

Figure 3. Immunization schedule and antibody titre in a sheep injected intramuscularly with THC-hemisuccinate-BSA in the amounts shown. Titre is defined as the reciprocal of the dilution of antiserum that bound 50% of the 3H-THC label.

A wide range of doses and immunization schedules has been used successfully. A convenient schedule for immunization of rabbits is to inject 200-500 fjLg of conjugated protein, emulsified in complete Freund s adjuvant, intradermally and subcutaneously on the first day, and to inject the same dose in incomplete adjuvant on days 14 and 21. Serum can be obtained 5-7 days later. Further bleedings may be done weekly, with intra-dermal booster injections given if the serum antibody levels fall. After an... 

The polyclonal antibodies obtained by immunizing experimental animals have been and will continue to be satisfactory reagents for many immunoassay methods. Choices can be made among adjuvants, routes of injection, dosage and immunization schedules, species of animal to be immunized, etc. (2-6, 28-31). 

Immunization schedules and fusion protocols (for monoclonals) should be documented. A good antibody pool of either polyclonal or monoclonal must exist. Storage precautions, such as the use of... 

Production of antisera does not require specialized immunological techniques and cell culture facilities. Therefore it may be a simpler, faster and cheaper way than production of monoclonal antibodies (see section 3.3.). However, it must be noted that antisera-based immunoassays are sometimes less selective than monoclonal antibody-based immunoassay because of the polyclonality of antibodies in the antisera, and good antisera are not reproduced. The production of high affinity antisera may be helped by long-term immunization schedules from the mechanism of antigen-dependent B lymphocyte differentiation and selection (23). 

Antibody specificity and affinity are modified by manipulating the immunization schedule. After the immunization procedure is finished, antibodies need to be characterized in depth to ensure specificity and affinity, which will help select the best-performing antibodies before they are used in assay development. Serum containing antibodies can be used as is, without further treatment, but antibodies can also be purified. Several methods are available to purify antibodies from serum, but the most common procedures use the IgG-binding protein A (or protein G). Purification of antibodies is required when they have to be conjugated to other molecules, such as enzymes, latex and gold particles, radioactive isotopes, or fluorescent labels. Undesired cross-reacting antibodies can be eliminated by im-munoaffinity purification. 

In rats, cells from immime lymph nodes are an excellent sotirce of specific B cells and we use routinely cells taken from the mesenteric nodes of animals immunized via the Peyer s patches. As with spleen cells, the animals are rechallenged via the Peyer s patches three days before removing the mesenteric nodes for fusion. Using this route for immunization we have successfully prepared rat X rat IgA-secreting hybridomas following a short immunization schedule whereas hyperimmunization 5nelded high affinity IgG antibodies (14). 

Janah S, Hussain QZ, Chaudhuri SN. 1970. Effect of hydrocortisone on immune cytokinetics. Part 1-Effects of different dose schedules on 19S and 7S antibody forming cells in Jeme s plaque technique. Indian J Med Res 58 1206-1216. 

Immunization procedures vary and are dependent on type of antigen to be used, duration of immunization process, and the amounts of immune product needed. The antigen suspension may be administered intravenously, intramuscularly, or subcutaneously. The amount of antigen injected can range from 1 to 200 mg. The quantity is determined by the availability of and the potency of the antigen. The time schedule also varies. Protocols for the three types of immunizations used to produce anti-carbohydrate antibodies are recorded in the following. 

Four rabbits were immunized each with 0.3 mL of the nonviable suspension of cells administered daily intravenously for 3 days, followed by a rest period of 4 days. This schedule was repeated for 5 weeks. After a 1-week rest period, a second administration of vaccine was used following the foregoing schedule. Blood samples were drawn weekly and serum was obtained. In 6 weeks the sera of the rabbits showed a high titer of antibodies directed at the cell-wall polysaccharide. The antisera from each rabbit were maintained separately. The antibodies were isolated from the serum by an affinity-chromatography procedure employing adsorbtion on lactosyl-... 

For immunization, a concentrated solution of gum arabic was prepared by dissolving 320 mg of the gum in 2 mL of sterile phosphate buffer (0.02 M phosphate, pH 7) in saline.49 This solution was then mixed with an equal volume of Freund s complete adjuvant, and samples of 0.4 mL of the suspension were injected intramuscularly in the hind leg of a rabbit weekly in alternate legs for 6 weeks. The animal was then allowed to rest for 2 weeks and the injection schedule was repeated. Four cycles of immunization were used to obtain sera containing a high titer of antibodies. Blood samples were drawn in the second and subsequent cycles and antisera were prepared from the samples by conventional methods. 

Procedures for preparation of the immunizing antigen, injection schedules, and assays for antibody formation are similar to those used for helical polynucleotide-MBSA antigens and are discussed in detail in the following section and in Vol. 12B [174] of this series. 

All three vaccine preparations may be administered for preexposure prophylaxis as a three-dose series of 1 mL IM on days 0 and 7 and once between days 21 and 28. Alternatively, HDCV can be administered intradermally in a dose of 0.1 mL using the same schedule. HDCV must be given using the specific intradermal dosage form and syringe. Lower rabies antibody concentrations have been observed in individuals immunized using the intradermal route while taking malaria prophylaxis concurrently. The IM route is recommended in this situation. ... 

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