Question

Case:

A 6-year-old boy is brought to the clinic where his mother reports that he was bitten by a neighbor’s dog two days earlier. The child’s right hand is lacerated between the thumb and index finger and this area is inflamed but healing. The doctor’s examination reveals small but painless swellings beneath the skin inside the right elbow and arm pit and he explains to the mother that these are active lymph nodes enlarged in response to the infection in the hand.

Questions:

6. What has produced the swelling?

7. Many immune-related cellular activities are often impaired in aged patients. Which lymphoid organ(s) normally develop less functionality and increasing amounts of adipose tissue with age?

8. Immunologists recognize two partially overlapping lines of defense against invaders and/or other abnormal, potentially harmful cells: innate immunity and adaptive immunity. In the case above, which would likely to occur first? What is innate immunity? Explain.

Case:

A 30-year-old woman with a history of infertility is discovered to have a high titer of antisperm antibodies.

Questions:

9. Immunoglobulins of humans fall into five major classes. Which immunoglobulin classes most likely provides acquired “immunity” against spermatozoa in the reproductive tract of this patient? Explain.

10. This immunoglobin class is mainly produced in an initial response to an antigen.

11. This immunoglobulin class can cross the placental barrier and confers passive immunity against certain infections until the newborn’s own adaptive immune system is acquired.

Answer 1

6

Swelling is the result of the increased movement of fluid and white blood cells into the injured area. The release of chemicals and the compression of nerves in the area of injury cause pain.
Lymph nodes are small glands that filter lymph, the clear fluid that circulates through the lymphatic system. They become swollen in response to infection and tumors.
The lymph nodes act like a military checkpoint. When bacteria, viruses, and abnormal or diseased cells pass through the lymph channels, they are stopped at the node.

When faced with infection or illness, the lymph nodes accumulate debris, such as bacteria and dead or diseased cells.

7
Thymus
One of the major characteristics of vertebrate immunology is thymic involution, the shrinking of the thymus with age, resulting in changes in the architecture of the thymus and a decrease in tissue mass.T-cells are named for the thymus where T-lymphocytes migrate from the bone marrow to mature. Its regression has been linked to the reduction in immunosurveillance and the rise of infectious disease and cancer incidence in the elderly

8
Innate immunity.(when a given pathogen is new to the host, it is initially recognized by the innate immune system and then the adaptive immune response is activated (2). Innate immunity is the host's first line of defense and is intended to prevent infection and attack the invading pathogens.)
Innate immunity:The innate immune system is made of defenses against infection that can be activated immediately once a pathogen attacks. The innate immune system is essentially made up of barriers that aim to keep viruses, bacteria, parasites, and other foreign particles out of your body or limit their ability to spread and move throughout the body. The innate immune system includes:
Physical Barriers
such as skin, the gastrointestinal tract, the respiratory tract, the nasopharynx, cilia, eyelashes and other body hair.
Defense Mechanisms
such as secretions, mucous, bile, gastric acid, saliva, tears, and sweat.
General Immune Responses
such as inflammation, complement, and non-specific cellular responses. The inflammatory response actively brings immune cells to the site of an infection by increasing blood flow to the area. Complement is an immune response that marks pathogens for destruction and makes holes in the cell membrane of the pathogen
The innate immune system is always general, or nonspecific, meaning anything that is identified as foreign or non-self is a target for the innate immune response. The innate immune system is activated by the presence of antigens and their chemical properties.
Cells of the Innate Immune System
There are many types of white blood cells, or leukocytes, that work to defend and protect the human body. In order to patrol the entire body, leukocytes travel by way of the circulatory system.
The following cells are leukocytes of the innate immune system:
Phagocytes, or Phagocytic cells
Macrophages
Mast cells
Neutrophils
Eosinophils
Basophils
Natural Killer cells:
Dendritic cells