No abstract

Bursal (B) and thymic (T) lymphocytes from chickens sensitized to Mycobacterium tuberculosis (PPD) or human gamma globulin (hGG) produced an avian lymphocyte-inhibitory factor designated as LyIF-PPD or LyIF-hGG, respectively. A chemotactic factor (LCF) for peripheral blood leukocytes was elaborated only by T-cells sensitized to PPD and hGG. These factors were partially purified by HPLC and were characterized physiochemically. Maximum inhibitory activity for LyIF-PPD and LyIF-hGG occurred in peak fractions corresponding to molecular weight ranges of 29,000 to 52,000 daltons and 15,000 to 29,000 daltons, respectively. The inhibitory activity of B- and T-LyIF-hGG was lost after chymotrypsin and neuraminidase treatment. Maximum chemotactic activity for LCF-PPD and LCF-hGG was in peak HPLC fractions corresponding to molecular weight ranges of 9,000 to 16,000 daltons and 8,000 to 16,500 daltons, respectively. Chemotactic activity of LCF-PPD and LCF-hGG was lost following chymotrypsin treatment while it was not reduced after neuraminidase treatment. Both inhibitory and chemotactic activities were stable at 56 C for 30 min and resistant to changes in pH from 5 to 9. The precursor molecule for the lymphokine is made after antigen immunization, but activated in the presence of the sensitizing agent.