In vitro induction of antigen specific antibody synthesis and proliferation of T lymphocytes with acellular pertussis vaccines, pertussis toxin and filamentous haemagglutinin in humans

Abstract

The in vitro response of human B- and T-lymphocytes to the acellular vaccines JNIH-6 (containing pertussis toxoid and filamentous hemagglutinin), and JNIH-7 (containing pertussis toxoid), and to the purified components JNIH-4 (filamentous hemagglutinin) and JNIH-5 (pertussis toxin) was investigated. Pertussis toxoid and filamentous hemagglutinin induced specific Ig synthesis in vitro in lymphocytes obtained from convalescent pertussis patients as target cells. The antigen-dependent Ig production was demonstrated in lymphocyte culture supernatants by ELISA techniques and by a Chinese hamster ovary cell toxin neutralization assay. Particularly with JNIH-4, -6 and -7, high antibody titers were obtained.

At optimal antigen concentrations a marked lymphocyte blast transformation was found in lymphocyte cultures from whooping cough patients, but not in cultures of lymphocytes obtained from healthy volunteers. At high concentrations native pertussis toxin as well as the B oligomer (S2–5) of the toxin induced a strong proliferation of patient as well as control lymphocytes, indicating non-specific mitogenic activity. At lower concentrations lymphocyte blast transformation was seen in patient cultures only, which indicates an antigen-specific T-cell response. The A protomer (S1), dimer 1(S2 + 4) and dimer 2(S3 + 4) induced proliferation of patient lymphocytes, which demonstrates the presence of T-cell epitopes on these peptides.

The in vitro B-cell response and the lymphocyte blast transformation assay are both useful tools for estimating the potency of acellular pertussis vaccines in man. Spontaneously acquired and vaccine induced immunity to Bordetella pertussis can be investigated at the level of B- and T-lymphocytes.