Hi Nicole,

You're on the right track! Helper T cells are required to activate Killer T cells and B cells. They themselves have to first be activated to effector cells by antigen presenting cells.

I can't find the exact question you are referring to though, could you provide a bit more information about it and I can look again?

Thanks!

Hi Nicole!

I think the confusion around this question comes from how they are using the term "assistance." For this question, I would focus on ruling out incorrect answers, and choosing the most right answer.

The first answer that we can rule out is D. Although it does meet many of the things we are looking for, it is an innate immune cell and the question is asking for an adaptive immune cell.

The next answer we can rule out is B, regulatory T cells. We can rule these out because these are regulatory cells, and help mediate the immune cells as well as preventing auto-immunity. These cells do not act to remove cancerous cells.

That leaves us with A and C. I understand your thinking that Cytotoxic T cells need to be activated by Helper T cells, but by that definition Helper T cells cannot kill cancerous cells without Cytotoxic T cells. Because of that, it is important to think about the act of removing the cancerous cells. The only one that can do that on its own is A, cytotoxic T cells!

Hopefully that helps,

Taylor

You got it!