Percentages of CD4+ T regulatory cells and HLA-DR expressing monocytes in severe intra-abdominal infections. 
To study the immune status of patients with severe abdominal infections, we assayed percentages of CD4+ T regulatory cells (CD4+CD25+FOXP3+ Treg) and human leukocyte antigen DR (HLA-DR) expressing CD14+ cells in peripheral blood.  A total of 46 subjects with varying acute physiology and chronic health evaluation II (APACHE II) scores were included in the study.  There was a significant (p < 0.01) increase in the percentage of CD4+CD25+FOXP3+ Treg and a significant (p < 0.01) decrease in HLA-DR expressing CD14+ cells with increasing APACHE II score.  Such modifications may contribute to the aggravation of severe intra-abdominal infections.