Which of the following cells is a part of the adaptive immune response?

One component of the immune system is the neutrophil, a professional phagocyte that consumes invading cells. The neutrophil is ferried to the site of infection via the blood as pre-neutrophils, or monocytes, ready to differentiate as needed to defend their host.

In order to leave the blood and migrate to the tissues, where infection is active, the monocyte undergoes a process called diapedesis. Diapedesis is a process of extravasation, where the monocyte leaves the circulation by moving in between endothelial cells, enters the tissue, and matures into a neutrophil.

Diapedesis is mediated by a class of proteins called selectins, present on the monocyte membrane and the endothelium. These selectins interact, attract the monocyte to the endothelium, and allow the monocytes to roll along the endothelium until they are able to complete diapedesis by leaving the vasculature and entering the tissues.

The image below shows monocytes moving in the blood vessel, "rolling" along the vessel wall, and eventually leaving the vessel to migrate to the site of infection.

A scientist is investigating what attracts monocytes to the site of infection, thus prompting diapedesis. He finds that a class of soluble mediators are given off by infected cells. This soluble mediator is most likely __________.

Which of the following is not involved in innate immunity?

Which of the following is not part of the innate immune response of the body?

Type 1 diabetes is a well-understood autoimmune disease. Autoimmune diseases result from an immune system-mediated attack on one’s own body tissues. In normal development, an organ called the thymus introduces immune cells to the body’s normal proteins. This process is called negative selection, as those immune cells that recognize normal proteins are deleted. If cells evade this process, those that recognize normal proteins enter into circulation, where they can attack body tissues. The thymus is also important for activating T-cells that recognize foreign proteins.

As the figure below shows, immune cells typically originate in the bone marrow. Some immune cells, called T-cells, then go to the thymus for negative selection. Those that survive negative selection, enter into general circulation to fight infection. Other cells, called B-cells, directly enter general circulation from the bone marrow. It is a breakdown in this carefully orchestrated process that leads to autoimmune disease, such as type 1 diabetes.

The T-cells and B-cells described in the passage are both examples of lymphocytes. Lymphocytes are involved in adaptive immunity. Which of the following are characteristics of the adaptive immune system?

I. It shows a stronger reaction to a pathogen upon a second exposure, relative to the first

II. It is the first line of defense against a pathogen in the environment

III. It involves the use of macrophages and other professional phagocytes

In the event of re-infection with the same pathogen, which immune cell allows for a quick response?

Which of the following is not part of the adaptive immune response?

Which of the following correctly matches the type of immunity to the way it was recieved?

In the crusade to create a vaccine for Poliomyelitis, Jonas Salk and Albert Sabin created two separate vaccines that proved to be successful in preventing Polio onset.

The Salk vaccine, which is given by standard injection, contained virus particles inactivated by an organic solvent. This method has the advantage of inactivating each of the three Polio strains with no bias.

Albert Sabin's vaccine, given by oral inoculation via sugar water, contained live virus particles that had been genetically attenuated. With this method, each of the three Polio strains acquired separate mutations that made them unable to infect the human host cells. Strain 2 in particular contained one single nucleotide polymorphism in the internal ribosomal entry site (IRES) that prevented successful viral replication.

What type of immune response does inoculation with either vaccine stimulate? 

Duchenne Muscular Dystrophy is an X-linked recessive genetic disorder, resulting in the loss of the dystrophin protein. In healthy muscle, dystrophin localizes to the sarcolemma and helps anchor the muscle fiber to the basal lamina. The loss of this protein results in progressive muscle weakness, and eventually death.

In the muscle fibers, the effects of the disease can be exacerbated by auto-immune interference. Weakness of the sarcolemma leads to damage and tears in the membrane. The body’s immune system recognizes the damage and attempts to repair it. However, since the damage exists as a chronic condition, leukocytes begin to present the damaged protein fragments as antigens, stimulating a targeted attack on the damaged parts of the muscle fiber. The attack causes inflammation, fibrosis, and necrosis, further weakening the muscle.

Studies have shown that despite the severe pathology of the muscle fibers, the innervation of the muscle is unaffected.

What is the best characterization of the immune response described in the passage?