Booster injection

Artificially acquired immunity against some diseases may require periodic booster injections to keep an adequate antibody level (or antibody titer) circulating in the blood. A booster injection is the administration of an additional dose of die vaccine to boost the production of antibodies to a level diat will maintain die desired immunity. The booster is given months or years after die initial vaccine and may be needed because die life of some antibodies is short. 

Immunization procedures and schedules vary depending on the laboratory. Usually an initial series of injections is followed by booster injections some weeks later. Animals are generally bled 7-14 days after each booster injection and the characteristics of the serum determined. Serum may be collected or pooled following numerous booster injections and(or) the animal may be exsanguinated. 

Two goats were immunized three times during the first 2 weeks with 1 mg of the antigen emulsified in 1 ml of Freund s complete adjuvant at several subcutaneous sites near regional lymph centers. Booster injections of 3 mg of antigen were administered at monthly intervals. The animals were bled 7 days after each boost. After several months of immunization, the titer and affinity of the antibody response was judged sufficient for use. 

Antiserum Production The immunogen, carboxymethylmorphine-bovine-serum-albumin, is emulsified with equal volume of complete Freund s adjuvant. Initial immunization doses are injected into the New Zealand albino rabbits and later on this followed up with booster injections after a period of 6 weeks. The antiserum titer is determined with each booster dose injection and is duly harvested when the titre value is maximum. This is diluted suitably and employed in the radioimmunoassay. ... 

Immunization and Antibody Production The immunogen 3-hemisuccinyloxyflurazepam, is emulsified with complete Freund s adjuvant. It is injected intradermally into two female New Zealand albino (white) rabbits. Repeated doses are administered twice at interval of two weeks. Subsequently, booster injections of the thick-immunogen-emulsion-paste are administered after a span of 6-weeks. The antibody is harvested when its titer level is high enough, diluted to the suitable-level and employed in the RIA. 

After 10 days, booster injections of the same amount of antigen in incomplete adjuvant were given every 2 weeks for a total of seven injections. Antisera to dust fractions (AD) and to bract (AB) were pooled and concentrated approximately tenfold by 40% saturation with ammonium sulfate at 4°c. The precipitated... 

Dosage Three injections of 0.5 ml at one or two months interval followed by a booster injection administered one year after the primary vaccination. 

The preparation of any MAB commences with the generation of lymphocytes sensitized to the antigen of choice. Conventionally this is done by the immunization of a mouse against the antigen followed by repeated booster injections until a suitable serum response has been obtained. Optimal results are obtained if the immune... 

To produce monoclonal antibodies, the first antigen injection in mice is followed a few weeks later by a booster of the same antigen. When polyclonal antibodies are detected in the serum of mice a few days after the booster injection,... 

ARS2 dissolved in PBS was emulsified with an equal volume of Freund s complete or incomplete adjuvant. The emulsion was s.c. injected into male JW rabbits at an initial dose of 1.0 mg, followed by 0.5 mg injections every 2 weeks. Serum was collected 2 weeks after the last booster injection. 

Check the antiserum titer Repeat the booster injection, and proceed with the protocol if the titer is not satisfactory. 

A rabbit may be bled every week provided that booster injections are administered every 8-12 wk. When this schedule is followed a large volume of antiserum can be collected from a single animal. 

Where antigens are introduced into the body intravenously, they usually travel rapidly to the spleen, followed by the fast production of an antibody. Subcutaneous or lntradermal injection of antigens most frequently localizes in the lymph nodes and antigens that are inhaled favor local sensidzadon. In some cases, such as tetanus immunization, loxin produced by the bacteria may be slow and insufficient to provoke a significant immunologic reaction. Thus, the requirement for properly timed booster injections. 

Serial measurements of antibody response after primary immunization or a secondary booster injection. 

The immunisation procedure (at least 12 weeks with booster injections, addition of oil based adjuvants to stimulate the immunogenic response) gives rise to an antiserum representing a mixture of polyclonal antibodies which are produced by different immunocompetent cells and thus have different binding sites and affinities. 

Each sheep initially received 5 mg of protein in multiple injections at intervals of 5 weeks until a serum with a satisfactory precipitating potency was obtained. Generally, 2 booster injections were sufficient and blood was withdrawn 15 days after the last booster. The serum was purified by precipitation of the immunoglobulins with half a volume of a saturated ammonium sulfate solution and then dialysed for 4 days against a 0.9 % sodium chloride solution which was replaced every day. It was stored at -30 °C. 

Seven days after the booster injection, bleed the rabbit and prepare cell-free serum as described in this chapter. 

Administer similar booster injections in Freund s incomplete adjuvant after 8 and 16 wk. 

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... 

For booster injections, give 0.5 ml of emulsion intramuscularly either into each hind limb or into each fore limb, alternately. Bleeds (20-40 ml) may be taken for testing on two occasions between 7 and 10 days after each booster and similarly every 3-4 weeks thereafter if the antiserum is satisfactory. Further boosters may be given at minimum intervals of 4 weeks (but preferably not within 2 weeks of a bleed) although it may pay to rest the animal for 3-4 months after the second or third booster. 

After the multiple injections the animals should be left for at least 10 weeks before boosting. Antibody levels rise to relatively high titers during this time, however, and it is certainly worth taking a large bleed for testing after 8-10 weeks. All booster injections are given by the intramuscular route, and the method of treatment from the tenth week onward is thus exactly the same as for the previous schedule. 

---