title: Physiochemical characterization of lymphocyte inhibitory factor (LyIF) isolated from avian B and T cells.
abstract: Thymic (T) or bursal (B) lymphocytes from chicks sensitized to Mycobacterium tuberculosis produce an avian lymphocyte inhibitory factor (LyIF). The physiochemical properties of both T and B LyIF were established by ultrafiltration which yielded four fractions with molecular weight ranges of greater than 100,000; 50,000-100,000; 10,000-50,000; and less than 10,000; enzymatic treatment with chymotrypsin and neuraminidase; varying pH; and heat exposure. These studies demonstrated that the maximum activity for both T and B LyIF was within a molecular weight range of 10,000-50,000. Both were sensitive to chymotrypsin and neuraminidase treatment. Both were stable at 56 degrees C for 30 min and resistant to changes in pH from 5 to 9. T-Cell migration was inhibited equally by B or T LyIF, while B-cell migration was inhibited to a lesser extent by T LyIF and B LyIF. Further experiments should establish the reasons for these observed differences in cross-reactivity.
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002645:Chickens; D002918:Chymotrypsin / Q000494:pharmacology; D003429:Cross Reactions; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007961:Leukocyte Migration-Inhibitory Factors / Q000302:isolation & purification / Q000502:physiology; D008222:Lymphokines; D009439:Neuraminidase / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*; D014462:Ultrafiltration
chemical_list: D007961:Leukocyte Migration-Inhibitory Factors; D008222:Lymphokines; D009439:Neuraminidase; D002918:Chymotrypsin