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F1 mice make two species of antigen-specific, parental haplotype-restricted, T-helper factor whose restrictions correspond to the phenotype of the I-A determinants that they bear.
- Source :
- Immunology; Nov87, Vol. 62 Issue 3, p445-450, 6p
- Publication Year :
- 1987
-
Abstract
- Antigen-specific T-helper factor (ThE) bears I-A determinants and is I-A restricted in its action. This I-A restriction may be explained by ThF binding, and hence approximating antigen to its own I-A determinants, thereby facilitating recognition by the T cell (I-A presentation theory), or by a recognition site for I-A on the ThF which approximates the antigen to I-A<superscript>+</superscript> antigen-presenting cells (I-A recognition theory). When ThF is produced in F<subscript>1</subscript> mice there may be a dissociation between the I-A phenotype of the ThF and the I-A restriction of any recognition site for I-A. In practice, ThF is made by spleen cells from (CBA × B10)F<subscript>1</subscript> [(H-2<superscript>k</superscript> × H-2<superscript>d</superscript>)F<subscript>1</subscript>] mice pretreated with cyclophosphamide (100 mg/kg) and immunized with picrylated parental spleen cells intravenously (3 × 10<superscript>7</superscript>). This procedure produces haplotype-restricted contact sensitivity (corresponding to the parental cells) but the unfractionated F<subscript>1</subscript> ThF does not show haplotype-specific restriction in its action. In fact, the F<subscript>1</subscript> mice produces two species of ThE, each bearing determinants of the I-A molecule of one parental haplotype (k or d). When the two species were separated with monoclonal anti-I-A<superscript>k</superscript> and anti-I-A<superscript>d</superscript> antibodies, the genetic restriction in their action corresponded to the phenotype of the I-A determinants that they carried. In a further experiment, F<subscript>1</subscript> ThE was split into its constituent antigen-binding (Ag<superscript>+</superscript> )and antigen non-binding (Ag<superscript>-</superscript>)chains by reduction, and the two species of Ag<superscript>-</superscript> chains separated with monoclonal anti-I-A antibodies. After complementation with the Ag<superscript>+</superscript> chain, the two species of Ag<superscript>-</superscript> chains showed genetic restriction in their action that corresponded to the phenotype of the I-A determinants that they carried. These findings support the I-A presentation hypothesis that antigen-specific ThE acts by approximating antigen to its own I-A determinants, and hence facilitates recognition by I-A-restricted I cells. [ABSTRACT FROM AUTHOR]
- Subjects :
- ANTIGENS
PHENOTYPES
MONOCLONAL antibodies
T cells
LYMPHOCYTES
LABORATORY mice
Subjects
Details
- Language :
- English
- ISSN :
- 00192805
- Volume :
- 62
- Issue :
- 3
- Database :
- Complementary Index
- Journal :
- Immunology
- Publication Type :
- Academic Journal
- Accession number :
- 14008264