the major factors triggering specific antibody production against haemophilus influenzae type b outer membrane preparations were : the use of tonsil lymphocyte cultures instead of peripheral blood lymphocytes , foetal calf serum instead of human serum , t-cell growth factors as a non-specific lymphocyte activator , low concentrations of antigen ranging from 1 to 10 ng/ml , a cell concentration of 4 x 10 ( 6 ) cells/culture , and finally the removal of okt8 positive suppressor t-cells .
C0086418
human
C0021756
t-cell growth factors