Infectious Intruders

Virulence Factors of Different Pathogens

• Prions invade follicular dendritic cells in lymphoid tissue with the help of factors secreted by host B lymphocytes.
• Viruses use adhesion and invasion mechanisms to enter the nucleus of host cells and facilitate replication of the viral genome.
• Bacteria use adhesins, pili, and biofilm formation to resist host secretions and translocate bacterial proteins to cause host cell membrane engulfment.
• Enzymes such as collagenase, hyaluronidase, and lecithinase break down cell contents, and capsules resist phagocytosis by host cells.
• Protozoans like Toxoplasma gondii use microtubule protrusion and vacuolar membrane formation for entry and protection from lysosomes.
• Fungi use cell wall or capsule molecules for adhesion, and thermotolerance and conversion from saprophytic mycelium to parasitic yeast for invasion.
• Hormone receptors on fungal cells may change the incidence of certain fungal diseases between men and women.
• Hydrolytic enzymes secreted by fungi cause damage to host cells and provide nutrients for the fungus.
• Macroparasites like hookworms secrete immunomodulatory proteins to reduce host cell immune responses.
• Third larval stage (L3) of hookworms invades host via hair follicles and migrates through circulation to lungs, trachea, intestines.
• Ticks use highly specialized mouthparts to attach to host skin and secrete biologically active molecules to prevent vasoconstriction and inflammation.
• Opportunistic fungal infections are common in immunosuppressed patients like those with HIV/AIDS, chemotherapy, lymphoma.

Virulence Factors of Different Pathogens

• Prions invade follicular dendritic cells in lymphoid tissue with the help of factors secreted by host B lymphocytes.
• Viruses use adhesion and invasion mechanisms to enter the nucleus of host cells and facilitate replication of the viral genome.
• Bacteria use adhesins, pili, and biofilm formation to resist host secretions and translocate bacterial proteins to cause host cell membrane engulfment.
• Enzymes such as collagenase, hyaluronidase, and lecithinase break down cell contents, and capsules resist phagocytosis by host cells.
• Protozoans like Toxoplasma gondii use microtubule protrusion and vacuolar membrane formation for entry and protection from lysosomes.
• Fungi use cell wall or capsule molecules for adhesion, and thermotolerance and conversion from saprophytic mycelium to parasitic yeast for invasion.
• Hormone receptors on fungal cells may change the incidence of certain fungal diseases between men and women.
• Hydrolytic enzymes secreted by fungi cause damage to host cells and provide nutrients for the fungus.
• Macroparasites like hookworms secrete immunomodulatory proteins to reduce host cell immune responses.
• Third larval stage (L3) of hookworms invades host via hair follicles and migrates through circulation to lungs, trachea, intestines.
• Ticks use highly specialized mouthparts to attach to host skin and secrete biologically active molecules to prevent vasoconstriction and inflammation.
• Opportunistic fungal infections are common in immunosuppressed patients like those with HIV/AIDS, chemotherapy, lymphoma.

Virulence Factors of Different Pathogens

• Prions invade follicular dendritic cells in lymphoid tissue with the help of factors secreted by host B lymphocytes.
• Viruses use adhesion and invasion mechanisms to enter the nucleus of host cells and facilitate replication of the viral genome.
• Bacteria use adhesins, pili, and biofilm formation to resist host secretions and translocate bacterial proteins to cause host cell membrane engulfment.
• Enzymes such as collagenase, hyaluronidase, and lecithinase break down cell contents, and capsules resist phagocytosis by host cells.
• Protozoans like Toxoplasma gondii use microtubule protrusion and vacuolar membrane formation for entry and protection from lysosomes.
• Fungi use cell wall or capsule molecules for adhesion, and thermotolerance and conversion from saprophytic mycelium to parasitic yeast for invasion.
• Hormone receptors on fungal cells may change the incidence of certain fungal diseases between men and women.
• Hydrolytic enzymes secreted by fungi cause damage to host cells and provide nutrients for the fungus.
• Macroparasites like hookworms secrete immunomodulatory proteins to reduce host cell immune responses.
• Third larval stage (L3) of hookworms invades host via hair follicles and migrates through circulation to lungs, trachea, intestines.
• Ticks use highly specialized mouthparts to attach to host skin and secrete biologically active molecules to prevent vasoconstriction and inflammation.
• Opportunistic fungal infections are common in immunosuppressed patients like those with HIV/AIDS, chemotherapy, lymphoma.

Test your knowledge on the mechanisms used by different pathogens to invade and cause disease in their hosts. This quiz covers the virulence factors employed by prions, viruses, bacteria, protozoans, fungi, and macroparasites. Learn about adhesion and invasion mechanisms, secretion of enzymes and immunomodulatory proteins, biofilm formation, and more. This quiz is ideal for students, healthcare professionals, and anyone interested in understanding the complex world of infectious diseases.