Down-regulation of secondary in vitro antibody responses by suppressor T cells of mice treated with a tolerogenic conjugate of ovalbumin and monomethoxypolyethylene glycol, OVA(mPEG)13.
In previous studies from this laboratory it was shown that OVA(mPEG)n conjugates induced: (i) tolerance in mice with respect to IgG and IgE antibody responses to dinitrophenylated OVA (DNP-OVA); and (ii) OVA-specific suppressor T (Ts) cells which could down-regulate a primary immune response in vivo. For the present study, we have developed an in vitro culture system for assessing the activity of Ts cells of mice tolerized by an OVA(mPEG)13 conjugate. Spleen cells from mice which had been primed with DNP4-OVA in Al(OH)3 gel were cultured with DNP4-OVA to induce a secondary antibody response in vitro. After 6 days, cells secreting anti-DNP antibodies of the IgG1 class were enumerated by an immunoenzymatic plaque-forming cell assay. Addition to the culture of T cells from mice treated with 3 i.p. injections of 500 micrograms of OVA(mPEG)13 resulted in a 29-61% reduction in the number of IgG1 anti-DNP antibody-forming cells, in comparison with the effect of T cells from mice treated with PBS. It was concluded that this tolerogenic conjugate induced splenic Ts cells which were capable of suppressing secondary in vitro anti-DNP responses.
Mokashi
S
S
MCR Group for Allergy Research, Department of Immunology, University of Manitoba, Winnipeg, Canada.
Holford-Strevens
V
V
Sterrantino
G
G
Jackson
C J
CJ
Sehon
A H
AH
D000818:Animals; D000917:Antibody Formation; D015536:Down-Regulation; D005260:Female; D007108:Immune Tolerance; D066298:In Vitro Techniques; D051379:Mice; D008815:Mice, Inbred Strains; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology*; D011092:Polyethylene Glycols / Q000008:administration & dosage; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D011092:Polyethylene Glycols; C028210:monomethoxypolyethylene glycol; D010047:Ovalbumin