Immunization – basic concepts, passive immunization.

Immunization

The process of inducing immunity against a disease

Types of Immune System

Innate
Acquired

The natural or innate immune system

Recognition, mobilization, destruction– Against any molecule identified as foreign!

• Cells (+ cell membrane receptors):

  • Interstitial space: phagocytes/monocytes- macrophages, dendritic cells;

  • In circulation: monocytes, neutrophil granulocytes, NK (natural killer) cells

Cytokine production (IFN, IL, TNF), Chemokine production

• Humoral components: In circulation: antimicrobial enzymes, proteins, and peptides (e.g., defensins) – complement system proteins!

No antigen specificity, barriers

Adaptive or acquired immunity

Components: Cells (Th; Tc; Treg; B lymphocytes) – signaling molecules, receptors

Cytokine production, Chemokine production

Site of production is the bone marrow -> migration to lymphoid organs

Antigen specificity!

Passive immunisation

• Natural passive: Maternal antibodies crossing the placenta (IgG), breast milk (IgA)

• Artificial passive: Specific antibodies (immune serum, immunoglobulin) → immediate but short-term protection (a few days to 3–4 weeks)

Passive immunisation characteristics

• Contains antibody

• Immediate effect

• Short-term immunity

• No memory

• Ability to mount an immune response is not required

• Only helps humoral defense

Rapid but short-lived immunity