TABLE 2.

Maternal Responses Against Fetal Minor Antigens in Mice¹

FETAL ANTIGEN			MATERNAL LYMPHOCYTES
Antigen	Antigen Source2	Genetic control of antigen expression	Responding lymphocyte subset	Lymphocyte receptor transgene	Source of lymphocytes (GD)	Major findings	Reference
H-Y	Unspecified	Endogenous	CD8+ T cells	Anti-H-Y TCR transgene	Spleen, LN (GD7 - postpartum)	↑, then ↓ in number of H-Y reactive T cells Remaining H-Y-reactive T cells hyporesponsive ex vivo	Jiang and Vacchio, 1998
H-Y	Unspecified	Endogenous	CD8+ T cells	Anti-H-Y TCR transgene	Spleen (GD18)	Maternal CD28 required for clonal deletion and hyporesponsiveness to H-Y+ cells ↑ in H-Y memory cells	Vacchio and Hodes, 2003
H-Y	Unspecified	Endogenous	CD8+ T cells	Anti-H-Y TCR transgene	Spleen (GD18)	Fetal FasL required for hypo-responsiveness to H-Y+ cells	Vacchio and Hodes, 2005
H-Y	Unspecified	Endogenous	CD8+ T cells	Endogenous TCR	Soleen (postpartum)	↑ survival of male skin grafts in multiparous mice ↑ in H-Y memory T cells	James et al., 2003
Ovalbumin	Endovascular trophoblast	Transgenic	CD8+ T cells3 CD4+ T cells3	Anti-ovalbumin TCR transgene	Spleen, LN (multiple GD)	Proliferation but lack of accumulation of CD4+ and CD8+ ova-reactive T cells Antigen exposure starting at midgestation Cross-presentation of fetal antigen by maternal APC ↓ naïve phenotype	Erlebacher et al., 2007

¹Abbreviations: TCR, T cell receptor; LN, lymph nodes; GD, gestation day on which lymphocytes were examined.

²Unspecified antigen source indicates that fetal antigen could derive from either trophoblast or fetal tissues.

³Experiments in which responding lymphocytes were adoptively transferred.