Explore BrainMass

Explore BrainMass

    Flow cytometry

    Not what you're looking for? Search our solutions OR ask your own Custom question.

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    Hi. Can someone please check my answers to the following multi-part question, and explain the questions I couldn't answer or that I got wrong?

    This is an 11-part question (!), but I think it looks worse than it is. It's 60% of a 1-hour test, so I don't think it should take more than an hour to go through, at most.

    For the question, please go to the following website: http://tutor.lscf.ucsb.edu/instdev/sears/immunology/

    Click on prior examinations; password: gauchos

    Go to winter 2003 midterm, question #2. (My professor gave out previous years' exam questions, but not answers.)

    One thing I'm particularly concerned about in my answers is that I didn't take into account any differences between spleen lymphocytes and thymus lymphocytes, because I wasn't sure what those differences might be.

    Here are my answers:

    A. T cytotoxic cells -- because these are CD8+,CD4- lymphocytes.

    B. T helper cells -- because these are CD4+,CD8- lymphocytes.

    C. These are CD4-,CD8- (double negative) lymphocytes, so they could be either B cells or NK cells, both of which are lymphocytes that lack CD4 and CD8 markers.

    D. These are TCR(alpha,beta)+, CD8- lymphocytes, so they are probably T helper cells. They could also be NK cells (which would have an alpha beta T cell receptor, and would lack a CD8 marker.)

    E. TCR(alpha, beta)+, CD8+ lymphocytes = T cytotoxic cells.

    F. TCR(alpha,beta)-, CD8- lymphocytes = B cells. The only lymphocytes that lack T cell receptors are B lymphocytes.

    G. I'm not sure about this one. Could they be T cytoxic cells that have TCR(gamma, delta) instead of TCR(alpha, beta)?

    H. I'm *guessing* that it's the lower left quadrant based on the fact that those cells are CD4-,CD8- and hence can't function as T helper cells or T cytotoxic cells. But couldn't those cells be B cells or NK cells, rather than functionally immature cells?

    I. I have no idea. Please help!

    J. I would *guess* that the answer is T helper cells since there seem to be relatively small changes in their populations from the normal mice to the knockout mice. Or is a more accurate answer "all CD8- cells, including T helper cells, B cells, and NK cells"?

    K. I have no idea. Please help.

    Thank you!!

    © BrainMass Inc. brainmass.com December 24, 2021, 4:53 pm ad1c9bdddf