CORRELATION BETWEEN SPECIFIC IMMUNOSUPPRESSION AND POLYCLONAL B-CELL ACTIVATION INDUCED BY A PROTEIN SECRETED BY STREPTOCOCCUS-MUTANS

• Type: Article in International Scientific Journal
• Date: 1988

Authors

Paula Ferreira (Author) ICBAS; SOARES, R (Author) Other; RIBEIRO, A (Author) Other; ARALACHAVES, M (Author) Other

Journal

Title: Scandinavian Journal of Immunology

Vol. 27

Pages: 549-554

ISSN: 0300-9475

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 19 Citations

Scopus - 16 Citations

Other information

Authenticus ID: P-001-TF5

DOI: 10.1111/j.1365-3083.1988.tb02382.x

Abstract (EN): The relationship between polyclonal B cell activation and immunosuppressor effects induced by F5'EP-Sm, a non-cytotoxic protein secreted by Streptococcus mutans, was studied in C57BL/6 mice. Mice treated with F5'EP-Sm exhibited a considerable increase in splenic non-specific Ig plaque-forming cells (PFC) compared with untreated mice. The isotypic pattern of non-specific PFC responses favours IgG2a~IgG2b>IgG3>IgG1~IgM, when taken as a ratio between treated and untreated animals. When F5'EP-Sm was administered 2 days before immunization with sheep red blood cells (SRBC), the non-specific PFC production was accompanied by an ephemeral increase in specific PFC against SRBC 1 day after immunization, which was quickly replaced by a strong immunosuppression. In contrast, when F5'EP-Sm was injected after priming, there was little or no demonstrable suppression of specific PFC, and the increase of non-specific PFC was much less evident. The kinetic curves representing increase or decrease in relation to controls of specific and non-specific PFC are almost mirror images in each of the isotypes. The in vivo suppressor effect was abrogated in thymectomized mice, although the involvement of the T cell compartment is probably secondary to the B cell mitogen effect, since T-depleted spleen cells proliferate and synthesize non-specific Ig when stimulated in vitro with F5'EP-Sm.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6