Innate recognition

• Describe the role of interferons in response to viral infections(antiviral activity)

  Interferons inhibit viral replication within infected cells by inducing the expression of antiviral protein to disrupt the different stages of the viral life cycle, limiting viral spread and reducing viral load
• Describe the role of interferons (activation of immune cells)

  Interferons activate and modulate immune cells like natural killer cells, T cells and macrophages. They enhance natural killer cells cytotoxic activity and promote macrophage phagocytosis to clear virus.
• Describe the role of interferons (induction of antigen presentation)

  Interferons stimulate the expression of MHC molecules on infected cells, facilitating the presentation of antigens to T cells and activating specific immune responses against virus.
• Describe the role of interferons (Modulation of inflammatory responses)

  Interferons regulate the inflammatory responses duing viral infections by influencing the production of cytokines and chemokine as well as cell recruitment to balance immune response and prevent excessive tissue damage.
• Describe the role of interferons (Establishment of antiviral state)

  Interferons induce a cellular resistance state to viral infection in neighbouring cells, upregulating antiviral proteins and activating cellular defence mechanism to revisit viral replication and spread.
• Describe the role of macrophages in immune response

  Macrophages in phagocytosis engulf and digest pathogens, cellular debris and foreign particles through specialized receptors.
• Describe the role of macrophages (antigen presentation)

  Macrophages capture, process and present antigen to T cells via MHC molecules, initiating specific immune responses against pathogens.
• Describe the role of macrophages (cytokine production)

  Macrophages produce cytokines and chemokines that regulate immune responses by promoting inflammation and recruiting immune cells to infection sites which contribute to immune response balance.
• Describe the role of macrophages (Tissue repair and remodeling)

  Macrophages participate in tissue repair and remodeling, promoting wound healing, resolving inflammation, and aiding tissue regeneration post-injury or infection to maintain tissue integrity.
• Describe the role of macrophages (Immune regulation)

  Macrophages interact with immune cells like T cells, B cells and dendritic cells to regulate immune response by influencing their activation, differentiation, and function. Shaping the overall immune response and maintaining immune tolerance.
• Describe the role of macrophages( Defence against infections)

  Macrophages engulf and destroy pathogens producing antimicrobial substances and coordinating immune responses to eliminate infections. Also contributes to infection resolution and immune memory establishment.
• Attempt to define the immune system

  The immune system is a network of cells, tissues and organs that work together to defend the body against harmful pathogens such as bacteria, viruses, fungi, parasites and abnormal cells such as cancer cells. Its primary function is to distinguish between self and non-self to mount the right immune response.
• Explain the notion of self vs non-self recognition as a central paradigm

  The concept refers to the ability of the immune system to differentiate between the body's own cells and foreign cells. The immune system is trained to recognize and respond to non-self while tolerating self antigens to prevent autoimmune reactions. When the immune system encounters non-self antigens it triggers immune responses such as the production of antibodies and the release of inflammatory mediators to eliminate the invaders.