Differentiate between various ______ recognition receptors (PRRs) and describe their cellular localization and ligand specificity.

Explain the molecular distinctions between pathogen-associated molecular patterns (______) and damage-associated molecular patterns (DAMPS), including representative examples of each.

Illustrate the signaling pathways activated by major PRRs (e.g., TLRs, NLRs, RLRs), including downstream factors and cytokine production. (Fill in the blank)

Discuss the relevance of PRR signaling in health and disease, including the balance between protective immunity and pathological ______.

Analyze how tissue localization influences sentinel cell function and contributes to context-dependent ______ responses.

Evaluate potential therapeutic strategies targeting PRRs or DAMP signaling in infectious and ______ diseases. (Fill in the blank)

Sentinel cells (e.g., macrophages, dendritic cells, mast cells, epithelial cells) continuously monitor tissues for infection and damage, serving as the first line of ________ detection.

Pattern Recognition Receptors (PRRs) are germline-encoded receptors that recognize conserved microbial structures (PAMPs) and endogenous danger signals (______).

PAMPs include conserved aspects of microbial molecules such as LPS, flagellin, dsRNA, and unmethylated ______ DNA.

DAMPs include host-derived molecules that signal sterile cellular damage (apoptosis > ________).

PRRs are categorized into families based on their structure and localization: primarily TLRs, RLRs, and ______.

PRR engagement initiates intracellular signaling cascades involving adaptor proteins like MyD88, TRIF, and MAVS, leading to ________ activation.

Key transcription factors activated by PRR signaling include NF-κB, IRF3/7, and AP-1, which regulate expression of inflammatory cytokines, interferons, and ________ peptides.

JAK/STAT signaling is a major downstream pathway of many cytokine receptors activated during PRR signaling, and is targeted therapeutically in chronic ________ diseases.

Sentinel cell activation results in cytokine and chemokine release (e.g., TNF-α, IL-6, IL-1β), upregulation of costimulatory molecules used in adaptive immunity, and recruitment of ________ and antigen presentation cells.

Therapeutic exploitation of PRR pathways includes: Vaccine adjuvants (e.g., TLR agonists), Immunotherapies (e.g., STING agonists in cancer), and Anti-inflammatory agents (e.g., NLRP3 inhibitors, JAK inhibitors). Which of the following is NOT a therapeutic exploitation of PRR pathways?

What are cytokines?

Interleukin is a class of glycoprotein made by _______ for regulating immune responses.

Based on the diagram, what is the main difference between chemotaxis and chemokinesis?

Chemotaxis involves movement in a specific direction in response to a chemical gradient.

What is the first line of defense against pathogens according to the concept of innate immunity?

Which of the following is NOT a function of innate immunity?

Cellular receptors in innate immunity are:

Pattern recognition receptors (PRRs) can recognize which of the following?

Fill in the blank: PRRs can also recognize cellular damage, which is referred to as _______.

According to the diagram, what is the final outcome of the innate immune response?

Which of the following is NOT an innate cell?

Fill in the blank: The progenitor cell that gives rise to mast cells, granulocytes, and phagocytes is called the ________ progenitor.

Which of the following cells is considered to overlap between innate and adaptive immunity?

Dendritic cells and macrophages are types of phagocytes.

Which cell type is NOT listed as a granulocyte?

Kupffer cells are a type of macrophage found in the ________.

Langerhans cells are found in which tissues?

Alveolar macrophages are located in the ________.

Microglia are a type of macrophage found in the ________.

Which type of sentinel cell engulfs and digests pathogens, damaged cells, debris, and foreign substances?

Which type of sentinel cell processes antigen and presents it to circulating T/B cells (antigen-presenting cell or APC)?

Which type of sentinel cell is a resident cell of connective tissues with histamine and heparin granules and plays roles in allergy?

Which type of sentinel cell acts as a physical barrier with PRRs?

Which type of sentinel cell is a tissue-resident natural killer cell?

Which of the following is a type of granulocyte innate immune cell?

Fill in the blank: ________ are innate immune cells that are classified as granulocytes and are involved in fighting parasitic infections.

Basophils are a type of innate immune cell.

Which cell type is both a macrophage and a monocyte in the innate immune system?

Which of the following is NOT an innate immune cell?

What percentage of blood is made up of plasma?

Which of the following is NOT a component of plasma?

Which type of immune cell is tissue-resident and not circulating?

Granulocytes circulate, but mast cells are a non-circulating granulocyte that lives in tissue.

What is the percentage range of neutrophils among leukocytes?

Monocytes are ________ while macrophages are tissue-resident monocytes.

Which of the following statements is true?

Which main sentinel cells are found in the skin?

What is the special role of Kupffer cells in the liver?

Which tissue contains microglia as its main sentinel cells?

What is the special role of sentinel cells in the lung?

Dendritic cells and epithelial cells are the main sentinel cells in the gut.

Which tissue's sentinel cells are responsible for neuroimmune surveillance?

Once sentinel cells are activated, they initiate cytokine and chemokine production. Which of the following is NOT induced by this process?

Once sentinel cells are activated, they initiate upregulation of costimulatory molecules and adaptive immune cell molecules (T cells).

Type I IFN response is triggered by viral nucleic acid sensing. Fill in the blank: The receptors involved in this process are ______ and ______.

Once sentinel cells are activated, they initiate phagocytosis and ROS/Nitric Oxide production. Which cells increase phagocytic activity?

Fill in the blank: Generation of ______ and ______ for pathogen killing is a functional response of sentinel cells.

What does the abbreviation PRRs stand for?

Which of the following is recognized by Pattern Recognition Receptors (PRRs)?

Fill in the blank: Damage-associated molecular patterns are abbreviated as _____

Pattern Recognition Receptors (PRRs) can be found only on the cell surface.

Which of the following is NOT a function initiated by PRRs?

What is the ligand for TLRs (Toll-like receptors)?

Where are NLRs (NOD-like receptors) localized?

Which PRR class is responsible for triggering Type I IFN production (antiviral response)?

What is the example function of CLRs (C-type lectin receptors)?

Which PRR class recognizes cytosolic DNA?

Which PRRs are located on the cell surface?

What does TLR2 detect?

What does TLR4 detect?

What does TLR5 detect?

What type of microbes do cell surface PRRs detect?

Which PRRs are endosomal?

What does TLR3 detect?

What do TLR7 and TLR8 detect?

What does TLR9 detect?

What do endosomal PRRs detect?

Which PRRs are cytosolic?

What do cytosolic PRRs detect?

PRRs are constitutively expressed by _______ immune cells and sentinel cells. (Fill in the blank)

Expression of PRRs can be upregulated by certain cytokines.

Some PRRs are enriched in antiviral sentinel cells like _______.

MULTIPLE PRRs can be activated simultaneously!

PRR signaling can be context-dependent – viral vs bacterial vs fungal vs cancer.

Negative regulators do exist to prevent overactivation of PRRs.