1. What is the primary difference between innate and adaptive immunity?
2. What are the main mechanisms of innate immunity?
3. What innate immune cell is responsible for killing and removing cancer cells?
4. What are the two main antimicrobial proteins & how do they function?
5. Where do lymphocytes originate _________________________ & mature_________________. What is meant by maturation?
6. Which lymphocyte is responsible for production of antibodies?
7. Which lymphocyte is responsible for immunological memory formation?
8. Name & describe in one sentence each subset of t-lymphocytes.

ANSWER

Overview of Innate and Adaptive Immunity

Primary Difference between Innate and Adaptive Immunity

The primary difference between innate and adaptive immunity lies in their specificity and speed of response. Innate immunity is the first line of defense, providing immediate but non-specific protection against a wide range of pathogens. In contrast, adaptive immunity is highly specific and takes time to develop, recognizing and targeting particular antigens.

Main Mechanisms of Innate Immunity

Innate immunity employs various mechanisms including physical barriers (skin, mucous membranes), phagocytic cells (neutrophils, macrophages), antimicrobial proteins (complement, interferons), and inflammatory responses to detect and eliminate pathogens.

Innate Immune Cell Responsible for Killing and Removing Cancer Cells

Natural Killer (NK) cells are innate immune cells responsible for recognizing and killing cancer cells through the release of cytotoxic granules.

Main Antimicrobial Proteins and Their Function

The two main antimicrobial proteins are complement and interferons. Complement proteins enhance phagocytosis and inflammation, while interferons inhibit viral replication and enhance immune responses.

Lymphocyte Origin and Maturation

Lymphocytes originate from hematopoietic stem cells in the bone marrow and mature in specific primary lymphoid organs such as the thymus (T cells) and bone marrow (B cells). Maturation involves the development of functional receptors and the elimination of self-reactive cells.

Lymphocyte Responsible for Antibody Production

B cells, a type of lymphocyte, are responsible for antibody production. When activated, B cells differentiate into plasma cells that secrete antibodies targeting specific antigens.

Lymphocyte Responsible for Immunological Memory Formation

Memory T cells, a subset of T lymphocytes, are responsible for immunological memory formation. They “remember” previous encounters with antigens, leading to faster and more robust immune responses upon re-exposure.

T-Lymphocyte Subsets

Helper T cells (Th): These lymphocytes stimulate immune responses by releasing cytokines that activate other immune cells, aiding B cells in antibody production and activating cytotoxic T cells.
Cytotoxic T cells (Tc): These lymphocytes directly kill infected or abnormal cells by releasing cytotoxic substances, such as perforin and granzymes.
Regulatory T cells (Treg): These lymphocytes maintain immune homeostasis by suppressing excessive immune responses and preventing autoimmune reactions.

In summary, innate immunity provides immediate non-specific defense mechanisms, while adaptive immunity is highly specific and memory-driven. Innate immunity relies on physical barriers, phagocytic cells, antimicrobial proteins, and inflammation. NK cells eliminate cancer cells, complement and interferons fight infections, and B cells and memory T cells contribute to antibody production and immunological memory, respectively. Helper, cytotoxic, and regulatory T cells are distinct subsets of T lymphocytes with specialized functions.