1. Immunoprophylaxis (prophylactic immunization)

2. Immunoprophylaxis Types of immunization Immunoglobulins and vaccines Strategies in vaccine preparation Mechanisms of action of different types of vaccines

3. NATURAL ARTIFICIAL (PROPHYLACTIC) ACTIVE PASSIVE IMMUNIZATION Immunity after infection Transplacental transfer of IgG Immunoglobulines in milk (breast feeding) Immunoglobulins and antisera (antitoxins) Vaccination

4. Pasive immunization (Administration of immunoglobulins/antisera) For prophylaxis or therapy Human immunoglobulins (from blood donors) Animal (horse) sera (antisera, antitoxins) e.g. for snake venoms, botulism, diphteria... immediate effect temporary immunity (weeks, months) Antibodies-Immunoglobulins (Ig) - human serum (gama)globulin (Ig of various specificity) - specific immune globulins (high-titre of specific Ig) serum disease!!! e.g. for hepatitis B, tetanus, rabies... e.g. for immunodeficiencies...

5. Active immunization (Vaccination) Requires time (weeks) for induction of immune response Administration Long-lasting immunity - prior to exposure to pathogen (exception: rabies vaccine) - post-exposure (in combination with specific Ig) - multiple doses needed for most vaccines Herd immunity Primarily for prophylaxis Adjuvant - increases immunogenicity

13. Vaccine types Live (attenuated) vaccines Inactivated (killed) vaccines - contain killed whole infectious agents Conjugate vaccines - contain structural parts/products of infectious agents New approches for vaccines obtained from pathogens by isolation and purification synthetic (genetic engineering) Subunit (antigenic) vaccines - contain live, attenuated (weakend) infectious agents Combined (polyvalent) vaccines - contain T-independent antigen bound to T-dependent antigen - contain several antigens of one or more different pathogens

14. Live (attenuated) vaccines Examples Advantages Induction of both humoral (Abs) and cellular response (CTLs) Several viral vaccines (against polio (oral-Sabin), mumps, measles, rubella, varicella) and some bacterial (BCG for tuberculosis)... Long-lasting immunity (administered in one or two doses) Limitations Risk in immunocompromised persons Instability (termolabile) Principle Imunization with attenuated (weakened) pathogen BCG (limited efficacy)

15. Inactivated (killed) vaccines Greater stability Vaccines against pertussis, typhoid, polio (Salk), influenza... Safety (no risk of infection) Shorter immunity (multiple, booster administration required) Low immunogenicity (only Ab induced, adjuvant required) Examples Advantages Limitations Principle Imunization with killed (inactivated) whole infective agents

16. Subunit (antigenic) vaccines Vaccine against pertussis (acellular), tetanus and diphteria (toxoid), influenza (Hemagglutinin and Neuraminidase), hepatitis B (HBsAg) and human papilloma virus (L1 protein) – so-called virus-like particles (VLP), pneumococcal and meningococcal polysaccharide vaccines... Same as for inactivated vaccines (lower immunogenecity) Examples Advantages Limitations Principle Same as for inactivated vaccines (greater safety) Immunization with structural antigens (protein or polysaccharide) of pathogens or their products (e.g. toxoid)

17. Conjugate vaccines Principle Immunization with capsular polysaccharide antigen of one pathogen (weak immunogen in children) conjugated to protein antigen of another pathogen (strong immunogen)

18. Principle of immunization with conjugated vaccines

22. Conjugate vaccines Good immune response to capsular antigens Vaccines against pneumococcus, menigococcus and H. influenzae type B (capsular polysaccharide bound to diptheria toxoid ) Efficient in children in the first two years of life and asplenic persons Relatively high cost Same as for subunit vaccines Example Advantages Limitations Principle Immunization with capsular polysaccharide antigen of one pathogen (weak immunogen in children) conjugated to protein antigen of another pathogen (strong immunogen) Same as for subunit vaccines

23. Combined (polyvalent) vaccines Practical (fewer administration, fewer visits of doctor...) Vaccines against tetanus, diphtera and pertussis (DTP), measles, mumps and rubella (MMR), polysaccharide or conjugate pneumococcal vaccines... Same as for single vaccines Examples Advantages Limitations Principle Simultaneous immunization with several serotypes of one pathogen (either attenuated strains or antigens) or several different pathogens The same as for appropriate single vaccines Good immune response to every component in vaccine

24. New approaches for vaccines (Hybride vaccines with live viral vectors) Immunization with live viral vectors (e.g. vaccinia virus) with introduced genes for immunodominant peptides of different pathogens Repeated administration not possible Ongoing clinical trials for several vaccines (e.g. against HIV) Examples Advantages Limitations Principle Induction of both humoral (Abs) and cellular immune response (CTLs) Possibility of polyvalent vaccine preparation

25. Injection of bacterial plasmid with DNA containing genes for various microbial antigenes Mechanism of action and possible adverse effects not well understood Ongoing clinical trials for several pathogens Simple handling, possibility of polyvalent vaccines preparation Example Advantages Limitations Principle Induction of both humoral (Abs) and cellular immune response (CTLs) New approaches for vaccines (DNA vaccines)

26. transplacental transfer of IgGj. Adjuvants increase10. immunogenicity of antigens in vaccinesi. Conjugate vaccines induce production of9. immunity after recovery from infectious disease h.Combined vaccines contain8. high-affinity antibodies to polysaccharidesg. Inactivated vaccines contain7. parts of infective agents or their productsf. Subunit vaccines contain6. induce production of mucosal IgAe. Live attenuated vaccine against polio5. whole killed microorganismsd.Example of natural passive immunization is 4. immunity to tetanus after injection of antitetanus immunoglobulins c. Example of natural active immunization is 3. immunity to tetanus after injection of tetanus toxoid b. Example of artificial passive immunization is 2. antigens from different infectious agentsa. Example of artificial active immunization is 1. 1.____2.____3.____4.____5.____6.____7.____8.____9.____10.___ bch j efdagh