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Vaccine Adjuvants in Immunotoxicology
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
Active immunity occurs when encountering a specific antigen or with the transfer of the antibodies protecting against antigens. It is acquired through immunization or getting through the disease itself (Baxter 2007). Moreover, the immune system usually responds within hours thanks to the presence of memory B and T cells when encountering the agent again later. During the active immunity process, the main mechanism providing the relation between innate immunity and adaptive immunity which is acquired weeks later is the ability to perceive the pathogen-associated molecular patterns (PAMPs) which innate immunity considers foreign substances (Peterfalvi et al. 2019; Maughan, Preston, and Williams 2015). This recognition occurs via the class-specific pattern recognition receptor (PRR) which is available in the innate immune system. The most important PRR in innate immunity is a toll-like receptor (TLR). The innate immune system considers PAMPs in a microorganism as a signal of danger and stimulates the adaptive immune system (Ivanov et al. 2020). Antigen-presenting cells (APCs), which are present in the circulation system and are the supervisory components of the immune system, are the group of cells which encounters a pathogen first and define it as “foreign.”
B Cells and Humoral Immunity
Published in Constantin A. Bona, Francisco A. Bonilla, Textbook of Immunology, 2019
Constantin A. Bona, Francisco A. Bonilla
As one might guess, active immunity is the response generated during encounter of the immune system with antigen. This may occur during the course of a natural infection, or after intentional antigen administration (vaccination).
The Prevention of Diphtheria
Published in Sir Arthur Newsholme, The Story of Modern Preventive Medicine, 2015
More recently diphtheria toxin has been treated with formalin, and its toxicity thus reduced: and it would appear that this use of toxoid and toxoid-antitoxin gives good results without some of the disadvantages of the earlier method. A series of injections are given, occupying a period of two or three weeks. Immunity does not immediately develop, but is increasingly established in 3 to 9 months. It would appear that the active immunity thus developed is comparable with the immunization established as adult life is approached by most members of an urban community; presumably by intermittent exposure to small doses of infective material, inadequate to cause a definite clinical attack. The evidence so far gathered points to effective protection lasting for at least six years, which means artificial protection at the most dangerous ages, this protection merging into the natural acquired immunity of adult life. The method has also proved its value in protecting nurses exposed to diphtheria infection; and it can be applied with great success to susceptible children in residential institutions when an outbreak of diphtheria occurs.
Immunization, not vaccination: monoclonal antibodies for infant RSV prevention and the US vaccines for children program
Published in Journal of Medical Economics, 2023
Infant vaccination, like all vaccination and past infections, confers active immunity, that is, immunity resulting from the work of antibodies generated by the individual’s own immune system, which has been taught to recognize the pathogen by vaccines or past infection28. However, infant vaccination is unlikely to be effective until the infant immune system has sufficiently matured to actively generate its own antibodies, which may happen only six months after birth29. Thus protection during the first six months of life likely benefits from passive immunity, where the antibodies come from an external source28, through either MV or mAbs. MV stimulates antibody production by the maternal immune system (providing active immunity to the mother) and transplacental transfer of such antibodies to the infant (providing passive immunity to the infant). With mAbs, the dose itself contains the antibodies30.
Combined vaccines for prophylaxis of infectious conditions
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Pravin Shende, Mansi Waghchaure
DTaP-IPV-Hep B-Hib is a hexavalent combined vaccines and consists of diphtheria with two acellular pertussis antigens (PT and PHA) and tetanus toxoids, Hib and inactivated poliovirus vaccine (IPV-types 1, 2 and 3). The action of vaccine includes the stimulation of active immunity through endogenously produced antibodies to fight against diphtheria, tetanus, hepatitis B, pertussis, Hib and poliovirus. The vaccine delivers primary as well as booster immunization against major childhood diseases simultaneously. Prior vaccination no requirement of reconstitution as the formulation is available in the fully liquid form, hence the administration is facilitated and also decreases the risk of medication error. The vaccine is recommended to be used both for primary vaccination (three doses at least 4 weeks apart from 6 weeks of age) as well as for booster vaccination till 2 years of age. Hexaxim manufactured by Sanofi Pasteur (Lyon, France) is a liquid suspension intended to be used as primary immunization for infants and booster immunization up to 24 months of age by intramuscular route [8]. The vaccination schedule is between 6 and 14 weeks or 2 and 6 months of age.
COVID-19 reinfection: the role of natural immunity, vaccines, and variants
Published in Journal of Community Hospital Internal Medicine Perspectives, 2021
Bao Y. Sciscent, Caroline D. Eisele, Lisa Ho, Steven D. King, Rohit Jain, Reshma R. Golamari
Properties of immunity from a previous infection will help characterize the reinfection potential [7,8]. According to Gomes et al., the duration of immunity matters[7]. In Figure 1 we depict that active immunity, from either infection or a vaccine provides full protection for a limited duration of time, which makes reinfection more likely[7]. In our review, we delve into previous studies and case reports related to reinfection. We must also determine the significance of a positive antibody test, which will deepen our understanding of the concept of reinfection.