1 The paper titled Dendritic cells loaded with stressed tumor cells elicit longlasting protective tumor immunity in mice depleted of CD4 CD25 regulatory T cells by Prasad et al reports that stressed and gamma irradiated syngeneic tumor cells elicit protective CD4 and CD8 T cell responses in the absence of dendritic cell DC maturation In the absence of infectious non self i e pattern recognition receptor PRR agonists do you think necrotic cells or apoptotic cells would be more effective at inducing DC activation Explain your reasoning 2 In the paper titled Involvement of chemokine receptors in breast cancer metastasis by M ller et al migration and invasion were assayed using fibronectin or Matrigel coated cell culture inserts chemotaxis or chemoinvasion assays A Which steps of the process of leukocyte extravasation are modeled in this system B Which steps of the process of leukocyte extravasation are not modeled in this system 3 Draw an idealized classical hepatic lobule Indicate the location of the central vein and the peripheral portal triads What is the relationship between Rappaport s hepatic acinus and the classical hepatic lobule You may use an explanation and or an illustration to answer the last part of this question 4 Cross priming refers to the activation of naive cytotoxic T lymphocytes CTL CD8 T cells by antigen presenting cells APC that have acquired nominal antigens from another cell Although injection of mice with MHC mismatched cells expressing minor H antigens has been shown to prime self MHC restricted CTL responses specific for the minor H antigens the biological relevance of cross priming in protective immunity against viral infection remains controversial Describe one experiment that could be performed to test that hypothesis that virus specific CTL are elicited by cross priming Be sure to state why the experimental result supports or refutes the hypothesis and how you control for direct priming 5 Answer the following question posted on a hepatitis B virus HBV testing and prevention web forum I donated blood and the results came back positive for anti nucleocapsid core protein anti HBc only Although the blood was trashed I thought this might have been a false positive result I donated blood a second time and got no notification that there were any problems with my blood and I was asked to donate again in the future which I did Now the third time I donated I was again anti HBc positive only Now I am told that I should never again in my entire life donate blood First of all why would my future donations be denied if I am not a carrier I wasn t positive for anything else It seems to me that HBV isn t a death sentence for most people greater than 90 clear the infection Aren t the odds of transmitting HBV from a person who has cleared the infection via blood transfusion very low Since we are desperate for donors is this really a necessary precaution