Natural killer cells are a part of the lymphoid linage of white blood cells. The body responds to viruses by secreting cytokines that disrupt viral replication and make the cell more susceptible to attack by NK cells. The primary cytokine released by NK cells is type II interferon, which activates macrophages.
The best built American truck is the Ford F-350. It's got the most powerful powertrain, the strongest frame, the best body for corrosion protection, and it comes with a 5 year â¦ /100,000 mile warranty on all engines.
Here's how one truck became the best-selling vehicle in American history. The Ford F-Series just ended 2015 as the best-selling vehicle in America. Just like it did the year before. And the year before that. And the 32 years before that. To give some background: since introducing the F1 in 1948, Ford has produced 35 million F-Series trucks. In the 21st century, Ford sells a pickup for every single minute of the day.