B7-1 and B7-2 have overlapping, critical roles in immunoglobulin class switching and germinal center formation

Immunity. 1997 Mar;6(3):303-13. doi: 10.1016/s1074-7613(00)80333-7.

Abstract

Humoral immune responses were characterized in mouse strains lacking either or both B7 molecules. Mice deficient in both B7-1 and B7-2 failed to generate antigen-specific IgG1 and IgG2a responses and lacked germinal centers when immunized by a number of routes and even in the presence of complete Freund's adjuvant. These results demonstrate that B7-mediated signaling plays a critical role in germinal center formation and immunoglobulin class switching in vivo. Mice lacking only B7-1 or B7-2 mounted high-titer antigen-specific IgG responses when immunized in complete Freund's adjuvant, indicating that B7-1 and B7-2 can have overlapping, compensatory functions for IgG responses. When immunized intravenously without adjuvant, B7-2-deficient mice failed to switch antibody isotypes or form germinal centers, whereas B7-1-deficient mice gave antibody responses comparable with wild-type mice. Thus, B7-2 has an important role in initiating antibody responses in the absence of adjuvant, but the induction of B7-1 by adjuvant in B7-2-deficient mice can compensate for the absence of B7-2.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Abatacept
  • Adjuvants, Immunologic / chemistry
  • Animals
  • Antigens / immunology
  • Antigens, CD / biosynthesis
  • Antigens, CD / physiology*
  • Antigens, Differentiation / biosynthesis
  • Antigens, T-Independent / immunology
  • B7-1 Antigen / biosynthesis
  • B7-1 Antigen / physiology*
  • B7-2 Antigen
  • CTLA-4 Antigen
  • Freund's Adjuvant / chemistry
  • Freund's Adjuvant / immunology
  • Germinal Center / drug effects
  • Germinal Center / immunology*
  • Germinal Center / metabolism
  • Haptens
  • Hemocyanins / immunology
  • Immunoconjugates*
  • Immunoglobulin Class Switching / drug effects
  • Immunoglobulin Class Switching / immunology*
  • Immunoglobulin Fc Fragments / biosynthesis
  • Membrane Glycoproteins / biosynthesis
  • Membrane Glycoproteins / physiology*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Knockout

Substances

  • Adjuvants, Immunologic
  • Antigens
  • Antigens, CD
  • Antigens, Differentiation
  • Antigens, T-Independent
  • B7-1 Antigen
  • B7-2 Antigen
  • CTLA-4 Antigen
  • Cd86 protein, mouse
  • Ctla4 protein, mouse
  • Haptens
  • Immunoconjugates
  • Immunoglobulin Fc Fragments
  • Membrane Glycoproteins
  • trinitrophenyl keyhole limpet hemocyanin
  • Abatacept
  • Freund's Adjuvant
  • Hemocyanins