title: The effect of killed influenza virus vaccine on the kinetics of normal human lymphocytes.
abstract: Inoculation of humans with wild or attenuated myxoviruses induces transient alterations in lymphocyte count and function. The effects of A/New Jersey/76 virus, a killed influenza virus vaccine, on circulating lymphocyte subpopulations were evaluated in 25 volunteers. Thymus-dependent (T) and independent (B) lymphocytopenias occurred 24 hr after vaccination. T lymphocytopenia was universal, profound (65% drop; P less than 0.001), and long-lived (greater than nine days). B lymphocytopenia was observed in 18 individuals, was moderate (39% drop]; P less than 0.001), and short-lived (less than three days). Null-cell counts rose concurrently, peaked three days after vaccination (188% rise P less than 0.001), and returned to prevaccination levels by day 28. Cell exposure to thymosin in vitro increased T-cell levels proportionately to the degree of null lymphocytosis (peaking three days after vaccination [45% conversion of null cells to T cells; P less than 0.001]), suggesting that postvaccination null cells might be emergent precursor T cells compensating for T lymphocytopenia. Seroconversion occurred in 90% of the volunteers by day 28, suggesting preserved effector B- and helper T-cell functions despite the marked changes in lymphocyte subpopulations.
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007252:Influenza Vaccines / Q000494:pharmacology*; D007958:Leukocyte Count; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects; D008231:Lymphopenia / Q000209:etiology*; D008297:Male; D013947:Thymosin / Q000494:pharmacology
chemical_list: D007252:Influenza Vaccines; D013947:Thymosin