Additionally, detailed analysis of CD4+ T-cells in acute coronary syndromes (ACS) revealed the expansion in peripheral blood of an unusual subset (Morishita et al. 1989), that does not express the co-estimulatory receptor CD28 (CD4+CD28null) (Liuzzo et al. 1999) (Zal et al. 2008). Here, CD4 is linked to acute coronary syndrome.