FIG. 2.

Adoptive transfer of immune splenocytes and subtypes of T lymphocytes. (A) Splenic lymphocytes (4 × 10⁷) collected 10 days postinfection from four inbred chickens (B²/B²) immunized by infection with 10³ CID₅₀ of A/Chicken/HK/G9/97(H9N2) influenza virus were adoptively transferred through the wing veins to four naive inbred chickens (B²/B²), and 1 day later chickens were challenged with 10 LD₅₀ of an H5N1 influenza virus. As a control, whole splenic cells from unimmunized chickens were transferred to naive chickens prior to challenge. Results were evaluated for deaths of chickens 15 days postchallenge. (B) Splenic T cells were collected from four inbred chickens (B²/B²) immunized 7 days earlier with 10³ CID₅₀ of A/Chicken/HK/G9/97(H9N2) influenza virus. T lymphocytes were depleted of CD4⁺ or CD8⁺ subtype of T cells using pan-mouse IgG-coated Dynabeads. Subtypes of T cells 2 × 10⁷ were transferred to four naive inbred chickens (B²/B²) through the wing veins, and 1 day later chickens were challenged with 10 LD₅₀ of an H5N1 influenza virus. As a control, CD4⁺ or CD8⁺ T cells from unimmunized chickens were transferred to naive chickens prior to challenge. Results were evaluated for deaths of chickens 15 days postchallenge.