CD4 and asthma: We speculated that C. sinensis, a liver fluke found predominantly in Asia including Korea and China, could be an alternative candidate of Schistosoma. Our speculation was supported by previous studies showing an inhibitory effect of C. sinensis protein in mice models of asthma and enteritis by inducing CD4+CD25+Foxp3+ T cells or IL-10 secreting macrophages (28, 29).