The human immune system is organized along two broad arms: innate immunity and adaptive immunity. The differences between these two approaches to immunity are not always black and white, but can be described in general terms with regard to immunological memory. Adaptive immunity displays this type of memory, and mounts a more intense response to pathogens upon second and subsequent exposures.

Within adaptive immunity, the system is further divided into humoral immunity and cell-mediated immunity. We can say that antibodies are the primary mediators of the former, while CD8 T-cell based cytotoxicity is the mediator of the latter.

CD4 T-cells, unlike their CD8 counterparts, are involved in both the humoral and cell-mediated arms of adaptive immunity. These CD4 cells drive isotype switching, a process that changes the types of antibodies produced after initial exposure to a pathogen to increase their molecular affinity. Additionally, CD4 cells promote the activity of macrophages to directly digest invading pathogens.

The innate immune system is usually the first system to respond to invading pathogens. As part of its initial response, innate immune cells must leave the circulation and enter the peripheral tissues where pathogens are present. The process by which immune cells leave the circulation is first initiated by adhesion proteins that make cells stick to the side of blood vessel walls, before they cross the vessel and enter the periphery. Which of the following proteins is most likely involved in mediating adhesion?

The human immune system is organized along two broad arms: innate immunity and adaptive immunity. The differences between these two approaches to immunity are not always black and white, but can be described in general terms with regard to immunological memory. Adaptive immunity displays this type of memory, and mounts a more intense response to pathogens upon second and subsequent exposures.

Within adaptive immunity, the system is further divided into humoral immunity and cell-mediated immunity. We can say that antibodies are the primary mediators of the former, while CD8 T-cell based cytotoxicity is the mediator of the latter.

CD4 T-cells, unlike their CD8 counterparts, are involved in both the humoral and cell-mediated arms of adaptive immunity. These CD4 cells drive isotype switching, a process that changes the types of antibodies produced after initial exposure to a pathogen to increase their molecular affinity. Additionally, CD4 cells promote the activity of macrophages to directly digest invading pathogens.

Neoplasms of the immune system are often classified by which surface proteins are present on rapidly dividing cells. A physician is evaluating a patient with a B-cell lymphoma. Which of the following normally present surface proteins is most likley used as a marker for a B-cell lymphoma?

A woman is admitted to the hospital in serious need of a blood transfusion. The woman is determined to have B negative blood.

Which of the following blood types can be transfused safely into the patient?

Which of the following is overexpressed during rheumatoid arthritis?

Which of the following is not a direct result of complement activation?

What is the function of a chemokine?