Thymic requirement for cyclical idiotypic and reciprocal anti-idiotypic immune responses to a T-independent antigen.

Abstract

The cyclical appearance of antibody-forming cells (AFC) 1 in the spleen and peripheral blood following a single antigenic stimulus is a well-documented phenomenon (1). Generally, within the 2-wk period after an antigen stimulus, two peaks of AFC are observed. The first peak occurs at ~4-6 d and the second at 10-13 d (1-8). Both T-independent (2-4) and T-dependent antigens (5-8) are capable of inducing very similar cyclical AFC responses in a wide variety of organisms.Various explanations for the cyclic production of AFC have been offered including: competition between free antibody and AFC precursors for persistent antigen (2, 6); sequential expression of various classes of antigen-specific immunoglobulin (5); the release of antigen by macrophages (2); regulation of AFC formation that is complement dependent (3); synchronous recruitment of memory B cells that is regulated by highly localized levels of specific antibody (7); and regulator T cells (8).Recently, results from our laboratory have indicated that the cyclical appearance of splenic plaque-forming cells (PFC) may be the result of cell-to-cell interactions based upon idiotypic recognition (4). We observed a cyclical production of splenic PFC after a single injection of heat-killed strain R36a Streptococcus pneumoniae (Pn) in BALB/c mice. Concurrent with the anti-Pn response was a cyclical and reciprocal expansion (or activation) of the clone(s) recognizing the dominant idiotype of the myeloma protein secreted by the TEPC-15 plasmacytoma (T-15) of the Pn-stimulated lymphocytes.As both T and B cells are known to participate in anti-idiotypic responses, we

Immunogenicity of an engineered internal image antibody.

“…Because anti-idiotype responses are T-cell-dependent phenomena (32), it will be important to elucidate the pathway of presentation and generation of T-cell help for peptide epitopes integrated within the immunoglobulin structure. Whatever the case may be, the results suggest that this approach may be valuable for immunization of individuals ofdifferent MHC haplotypes, an aspect of key importance for human vaccination against malaria P. falciparum sporozoite.…”

Biological activity of anti‐thyrotropin anti‐idiotypic antibody

“…There is now considerable evidence that interaction of anti-Id with Id is involved in the regulation of primary and secondary immune responses [l-71. Anti-Id arising as a result of immunization with T cell-independent antigens require the participation of functional T lymphocytes [8], as do the reciprocal oscillations over time of these complementary antibodies [9]. Depending on the type and mode of presentation of anti-Id antibodies, T helper or suppressor cells are triggered [2][3][4].…”

Rapid Induction of Splenic and Peritoneal B-1a Cells in Adult Mice by Thymus-Independent Type-2 Antigen

“…TI type-2 (TI-2) Ags are defined as those Ags capable of stimulating specific B lymphocyte proliferation and Ab secretion without the assistance of cytokines or costimulatory signals normally delivered during T cell:B cell interactions. Although T lymphocytes may participate in a TI-2 humoral response by modifying the extent of Ig isotype switching (4), the idiotypic composition (5), and even the magnitude (6, 7) of the response, there is no absolute requirement for the participation of T cells in the generation of a basic IgM Ab response specific for the TI-2 Ag. Although the mechanism of TI humoral responses have been extensively characterized (8), a number of important questions regarding the nature of the TI responses by B cells remain unanswered, including how B cells respond in the absence of T cell-derived cytokines and costimulatory signals, as well as the source, mechanism, and fate of B cells responding to TI-2 Ags during in vivo responses.…”