Noun. 1. interleukin-any of several lymphokines that promote macrophages and killer T cells and B cells and other components of the immune system. lymphokine-a cytokine secreted by helper T cells in response to stimulation by antigens and that acts on other cells of the immune system (as by activating macrophages).
Now, passengers must pay a flat fee of $5.60 in each direction, no matter how many plane transfers are made to get from one city to another. For passengers flying a nonstop round trip, that means the fee will increase from $5 to $11.20.Passengers flying round-trip with a connection each way will see their fees increase $1.20 to $11.20 per round trip, versus $10 before the fee increase.ost of the new revenue will go to pay down the federal deficit. Until Monday, a passenger was charged $2.50 for each leg of a journey. For a nonstop round trip, the cost was $5. For a round trip with a connection each way, the cost was $10. The fee was capped at two flights each way.
For additional information about security fees, please email your inquiry or call (571) 227-2323. From November 2001 through September 2014, TSA imposed a fee on air carriers equal to their costs of passenger and property screening in calendar year 2000. This fee is known as the Aviation Security Infrastructure Fee. The authority to impose this fee was repealed effective October 1, 2014, and any fees incurred by air carriers before this date are due to TSA. Read the payment instructions for air carriers to remit fees to TSA.