Human semen contains exosomes loaded with coding mRNA. (A) RNA analysis with the Bioanalyzer revealed that SE contains different RNA species. Arrows show peaks for 18 s, 28 s, and the horizontal line represents small RNA. (B and C) PCR analysis of tetraspanin (CD9 and CD63) mRNA and host restriction factors (HRFs) mRNA present in paired SE and spermatozoa samples. Numbers 1 to 5 represent different donors. GAPDH is present in SE and spermatozoa and was used as loading control.