IL-2 receptor

The interleukin-2 receptor (IL-2R) is a heterotrimeric protein expressed on the surface of certain immune cells, such as lymphocytes, that binds and responds to a cytokine called IL-2.

Composition

IL-2 binds to the IL-2 receptor, which has three forms, generated by different combinations of three different proteins, often referred to as "chains": α (alpha) (also called IL-2Rα, CD25, or Tac antigen), β (beta) (also called IL-2Rβ, or CD122), and γ (gamma) (also called IL-2Rγ, γ_c, common gamma chain, or CD132); these subunits are also parts of receptors for other cytokines. The β and γ chains of the IL-2R are members of the type I cytokine receptor family.

Structure-activity relationships of the IL-2/IL-2R interaction

The three receptor chains are expressed separately and differently on various cell types and can assemble in different combinations and orders to generate low, intermediate, and high affinity IL-2 receptors.

The α chain binds IL-2 with low affinity, the combination of β and γ together form a complex that binds IL-2 with intermediate affinity, primarily on memory T cells and NK cells; and all three receptor chains form a complex that binds IL-2 with high affinity (Kd ~ 10−11 M) on activated T cells and regulatory T cells The intermediate and high affinity receptor forms are functional and cause changes in the cell when IL-2 binds to them.

Ilyushin Il-2

The Ilyushin Il-2 (Cyrillic: Илью́шин Ил-2) Sturmovik was a ground-attack aircraft (Cyrillic: Штурмови́к, Šturmovík) produced by the Soviet Union in large numbers during the Second World War. With 36,183 examples of the Il-2 produced during the war, and in combination with its successor, the Ilyushin Il-10, a total of 42,330 were built, making it the single most produced military aircraft design in aviation history, as well as one of the most produced piloted aircraft in history along with the American postwar civilian Cessna 172 and the Soviet Union's own then-contemporary Polikarpov Po-2 Kukuruznik multipurpose biplane, itself sometimes seen side-by-side with the big armored Ilyushin monoplane on the front lines.

To Il-2 pilots, the aircraft was simply the diminutive "Ilyusha". To the soldiers on the ground, it was the "Hunchback", the "Flying Tank" or the "Flying Infantryman". Its postwar NATO reporting name was "Bark". The Il-2 aircraft played a crucial role on the Eastern Front. Joseph Stalin paid the Il-2 a great tribute in his own inimitable manner: when a particular production factory fell behind on its deliveries, Stalin sent an angrily worded cable to the factory manager, stating "They are as essential to the Red Army as air and bread." "I demand more machines. This is my final warning!"

IL-2

IL2 or IL-2 may refer to: