ENHANCEMENT OF SHEEP ERYTHROCYTE (SRBC)-INDUCED PLEURISY IN NONSENSITIZED MICE BY CYCLOPHOSPHAMIDE - DEMONSTRATION OF NATURAL CELL-MEDIATED IMMUNE REACTIVITY TO SRBC

  • 1 January 1982
    • journal article
    • research article
    • Vol. 47  (1) , 31-40
Abstract
Intrapleural injection of 2 .times. 108 sheep erythrocytes (SRBC) into normal C57BL/6N (B6) mice produced a low but significant exudate leukocyte reaction, which was delayed in onset and mononuclear cell dominant. Administration of 20-200 mg/kg cyclophosphamide (CY) in mice induced a dose-dependent enhancement of theis reaction. Erythrocytes of syngeneic and allogeneic mice, rats, guinea-pigs rabbits and humans showed no or slight enhancement in CY-treated B6 mice. Maximal enhancement was observed on day 6 after CY treatment, but the reactions fell on day 7 and gradually decreased thereafter. B6 mice from specific pathogen-free colonies also showed strong reactions on day 6 after CY treatment. B6 mice demonstrated the highest reactions and C3H/He (C3H) mice were intermediate, while BALB/c mice showed very low responses. F1 hybrid (BALB/c .times. B6) mice showed an intermediate response as compared with the parent strains. The enhanced reactions reached their peak at 24 h after SRBC injection and mainly consisted of macrophages and polymorphs. The enhancement was successfully transferred to naive syngeneic mice by viable spleen cells from CY-treated mice but not by sera. The mediator cells could not bind to plastic petri dishes or a nylon-wool column and were sensitive to anti-Thy-1.2 + C treatment. The enhancement was apparently induced by the cell-mediated immune (CMI) mechanisms. The appearance of natural CMI reactivity to SRBC and its role in relation to immunological reactions is discussed.