CD28 and systemic lupus erythematosus: 21 Kaneko Kaneko H H Saito Saito K K Hashimoto Hashimoto H H Yagita Yagita H H Okumura Okumura K K Azuma Azuma M M Preferential elimination of CD28 T cells in systemic lupus erythematosus (SLE) and the relation with activation- induced apoptosis Preferential elimination of CD28 T cells in systemic lupus erythematosus (SLE) and the relation with activation- induced apoptosis Clin Exp Immunol.