Antigen-presenting cell: A cell that can present antigen in a form that T cells can recognize it. The cells that can present antigen include B cells and cells of the monocyte lineage (including macrophages).
Generation X Ages | How Big Is Generation X? The age range for Generation X as of 2016 is 35 to 55 (my broadest definition). In 2011, the first Gen-Xer turned 50 years old and the youngest turned 30. We are currently the âsandwich generationâ in America. We are caring for aging parents and raising more than 50 percent of the nationâs children under 18.
Generation X. 1  For a few more years, Gen Xers are projected to remain the âmiddle childâ of generations â caught between two larger generations of the Millennials and the Boomers. 2  Though the oldest Gen Xer is now 50, the Gen X population will still grow for a few more years. The Gen X population is projected to outnumber the Boomers in 2028 when there will be 64.6 million Gen Xers and 63.7 million Boomers. The Census Bureau projects that the Gen X population will peak at 65.8 million in 2018. Baby Boomers. Baby Boomers have always had an outsized presence compared with other generations. They were the largest generation and peaked at 78.8 million in 1999. There were an estimated 74.9 million Boomers in 2015.