Introduction and Classification Natural Killer (NK) cells represent a category of cytotoxic lymphocytes primarily associated with the innate immune system while exhibiting functionalities that bridge innate and adaptive immunity. Classified as unconventional lymphocytes and members of the innate lymphoid cell (ILC) family, specifically Group 1 ILCs, NK cells constitute a principal effector population capable of […]

Main Definion of B Lymphocytes B lymphocytes are some of the most important cells of the immune system, especially in specific immunity. Together with T lymphocytes, they form the basis of the body’s protective barrier. They can very precisely recognize antigens using special “sensors” on their surface – B cell receptors (BCR for short). The […]

1. Identity and Core Task 2. Developmental Pathway in the Thymus 3. Antigen Recognition Architecture 4. Activation of Naïve CD8⁺ T Cells Signal Delivered by Outcome if Absent Notes 1. TCR engagement Peptide–MHC-I on dendritic cells No activation CD8 co-receptor stabilizes binding 2. Costimulation CD80/CD86 on DC ↔ CD28 on T cell Anergy or deletion […]

T helper (Th) cells, also referred to as CD4⁺ T lymphocytes, are a specialized subset of adaptive immune cells that play a pivotal role in coordinating immune responses. Their primary function is to regulate the activity of other immune cells—most notably B cells, cytotoxic T lymphocytes, macrophages, and innate lymphoid cells—through direct cell–cell interactions and […]