title: Procoagulant activity of PPD-stimulated human lymphocytes after cryopreservation.
abstract: OBJECTIVE
  Human mononuclear cells from a previously sensitized donor generate procoagulant activity (PCA) following stimulation with purified protein derivative (PPD). Lymphocytes of tuberculous pleural effusions are also highly responsive to PPD stimulation. We examined the influence of cryopreservation on lymphocytes following stimulation with PPD.
  
  
  METHODS
  Peripheral blood lymphocytes of 5 healthy PPD skin test positive subjects were incubated with either PPD, thromboplastin, or concanavalin A (Con A) at concentrations of 0, 1, and 10 micrograms/ml. PCA was determined by measuring the recalcification time. Tests were repeated following cryopreservation for 4 weeks.
  
  
  RESULTS
  Incubation of fresh lymphocytes led to a dose dependent shortening of recalcification time: PPD (0-1-10 micrograms/ml: 100-84-65%), thromboplastin (0-1-10 micrograms/ml: 100-85-62%), and Con A (0-1-10 micrograms/ml: 100-85-42%). These results were highly reproducible when tests were repeated 6 weeks later. Cryopreservation did not significantly affect the expression of PCA following incubation with PPD and with thromboplastin. In contrast, cryopreservation significantly diminished the degree of Con A generated PCA.
  
  
  CONCLUSIONS
  Cryopreservation and storage of human lymphocytes is possible without alteration of PCA expression following their incubation with PPD or thromboplastin.
authors.affiliation: Department of Research, University of Basel, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Hoheisel
authors.forename: M
authors.initials: M
authors.lastname: Roth
authors.forename: C H
authors.initials: CH
authors.lastname: Chan
authors.forename: P W
authors.initials: PW
authors.lastname: Ruff
authors.forename: D A
authors.initials: DA
authors.lastname: Tsakiris
authors.forename: M
authors.initials: M
authors.lastname: Hornung
authors.forename: A P
authors.initials: AP
authors.lastname: Perruchoud
mesh_terms: D001779:Blood Coagulation Factors / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D003208:Concanavalin A / Q000008:administration & dosage; D015925:Cryopreservation; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D013268:Stimulation, Chemical; D013925:Thromboplastin / Q000008:administration & dosage; D014373:Tuberculin / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D001779:Blood Coagulation Factors; D014373:Tuberculin; C045071:leukocyte procoagulant activity; D003208:Concanavalin A; D013925:Thromboplastin; D002118:Calcium