Term
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Definition
| Protection from infectious disease. |
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Term
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Definition
| First line of defense. Also called natural or native immunity. The natural resistance with which a person is born. Consists f the physical, chemical, molecular, and cellular defenses that are inplace before infection and can function immediatley as an effective barrier to microbes. Rapid response, minutes/hours. Defense: barriers (skin, mucous membranes), phagocytes, inflammation and fever.Cells: phagocytes(macrophages, neutrophils), natural killer cells, and dendritic cells. Molecules: cytokines, compliment proteins, soluble mediators. |
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Term
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Definition
| Second line of defense, responding less rapidly than innate immunity but more effectively. Also called specific or aquired immunity. Uses focused recognition of each unique type of foreign agent followed in days by an amplified and effective response. Slower response, days/weeks. Defense: cell killing; tagging of antigen by antibody for removal. Cells: T and B lymphocytes. Molecules: antibodies, cytokines. Further seperated into humoral and cell-mediated immunity. |
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Term
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Definition
| Or immunogens. Substances foreign to the host that elicit adaptive immune responses. Types: bacteria, fungi, viruses, protozoa, parasites, nonmicrobial agents (plant pollens, poisin ivy resin, insect venom, and transplanted organs). These foreign molecules are recognized by receptors on immune cells and by secreted proteins called antibodies or immunoglobulins, made in response to the antigen. |
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Term
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Definition
| Cells that specifically recognize and respond to foreign antigens. T lymphocytes (T cells- cell-mediated, memory), B lymphocytes (B cells- humoral immunity, memory), and NK cells (innate immune system, may be 1st line of defense against viral infections). |
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Term
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Definition
| Low-molecular-weight proteins secreted by cells of both innate and adaptive immune systems. Tumor necrosis factor, interleukins, interferons, and chemokines. Secreted in a brief, self-limiting manner. Synthesis is limited to new gene transcription resulting from cellular activation. Actions are pleiotropic (ability to act on different cells)and redundant (ability to stimulate the same or overlapping biologic functions). Actions are local or systemic. |
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Term
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Definition
| Proteins that have been divided into 5 classes: IgG, IgA, IgM, IgD, and IgE. Four polypetide structure. |
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Term
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Definition
| Abnormality in the immune system that renders a person susceptible to diseases normally prevented by an intact immune system. Classified as primary (congenital or inherited) or secondary (aquired later in life; result of malnutrition; disseminated cancers- lymphoma; infection of the cells of the immune system, most notably with HIV; etiologic agent of AIDS; and treatment with immunosuppresive drugs- corticosteroids or transplant rejection meds). |
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Term
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Definition
| Process of taking cells, tissues, or organs called a graft, from one individual, and placing them into another individual. Sometimes grafts are transplanted from another site in the same person. The individual who provided the tissue is called the donor. The individual who receives the graft is either called the recipient or host. Major barrier: process of rejection, in which the recipient's immune system recognizes the graft as foreign and attacks it. |
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Term
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Definition
| Process of taking cells, organs or tissues. |
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Term
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Definition
| Member of the lentivirus. Retrovirus that attacks the CD4 T lymphocytes, the immune cells responsible for orchestrating and coordinating the immune response to infection. More susceptible to severe infection with ordinarily harmless organisms. Transmitted from one person to another through sexual contact, blood-to-blood contact, or perinatally. Not spread by mosquitos or other insect vectors. Transmission can occur when infected blood, semen, or vaginal secretions from one person are deposited onto a mucous membrane or into the bloodstream of another person. Sexual contact (unprotected) is most frequent mode of transmission. Transmission from mother to infant is the most common reason children are infected. People with other STD's are at a higher risk. Person is infectious even when no symptoms are present. Point where person converts from negative to positive is called seroconversion, occurs 1-3 months after exposure and can take up to 6 months. Prevention: adopting risk-free or low-risk behavior, abstinence, latex condoms w/water based lubricants, avoiding drug use (syringes). |
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Term
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Definition
| Type of RNA virus that contains the enzyme reverse transcriptase, which allows its genetic information to be integrated into the host DNA. Retroviruses have a genome consisting of two RNA molecules, which may or may not be identical, from which they code for DNA. The genome of the retrovirus is then inserted into the DNA of a host cell with the help of an integrase enzyme. |
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Term
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Definition
| Infectious disease of the immune system caused by HIV, a retrovirus that causes profound immunosuppression. Enters the cell and transmits RNA to DNA of the host cell, allowing for viral replication. Diagnosed when the person has a CD4 count below 200 or an AIDS- defining illness occurs, these opportunistic infections that are characterized by the type of organism and are not typically found in persons who are not infected with the virus. Characteristics: profound immunosuppression, associated oppotunistic infections, malignancies, wasting, CNS degeneration. No cure. Transmitted through blood, semen, vaginal fluids, and breast milk. Cells affected: CD4 T lymphocytes, Macrophages, Dendritic cells. |
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Term
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Definition
| Mediated by molecules in the blood. The principle defense against extracellular microbes and toxins. Can result in: precipitation of antigen-antibody complexes, agglutination or clumping of cells, neutralization of bacterial toxins and viruses, lysis and destruction of pathogens or cells, adherence of antigen to immune cells, facilitation of phagocytosis, and complement activation.Two types of response: primary- antigen is first introduced to body, latent period before can be detected in serum; secondary or memory- occurs on second or subsequent exposure to antigen, rise in antibody occurs sooner and reaches a hiogher level because of available memory cells. |
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Term
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Definition
| Mediated by specific T lymphocytes. Defends against intracellular microbes such as viruses. Involves both CD4 and CD8 T lymphocytes. Most aggressive phagocyte- macrophage. Activated CD4 cells release various cytokines that recruit and activate other CD8 cells, macrophages, and inflammatory cells. Cytokines can induce positive migration or chemotaxis of several types of inflammatory cells, including macrophages, neutrophils and basophils. Activation of macrophages ensures enhanced phagocytic, metabolic, and enzymatic potential, resulting in more efficient destruction of infected cells. This type of defense is important against intracellular pathogens such as Mycobacterium and Listeria monocytogenes. |
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Term
| Hypersensitivity Disorders |
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Definition
| Involve an excessive or inappropriate response by the immune system to an antigen. This is too much of a good thing, which ultimately can cause tissue damage and destruction. Four types. |
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Term
| Immunodeficiency Disorders |
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Definition
| These disorders can be primary or secondary and involve a lack of an immune response. This leads to infections and disease without an adequate response by the immune system. Primary disorders are thought to be genetically transmitted and can involve humoral, cellular, or combined disorders. They can also be as a result of disorders in the complement system or phagocytosis. Need to be identified early if possbile due to the need for the infant to defend against illness, particularly with the introduction of immunizations. Secondary are aquired later in life and usually due to another factor such as malnutrition, medications that suppress the immune system, cancer, or infection such as HIV or AIDS. |
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Term
True or False
Rejection of transplanted organs is normally manifested during and immediately following transplantation? |
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Definition
False.
Patterns of rejection: hyperacute- occurs almost immediately after transplantation; acute- occurs within the first few months after transplantation and is evidenced by signs of organ failure; chronic- occurs over a prolonged period. |
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Term
True or False
Disorders of B cell function impair the body's ability to produce antibodies against disease? |
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Definition
False.
Defects in humoral immunity increase the risk of recurrent pyogenic infections. |
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Term
True or False
Latex allergies may be either a type I or type IV reaction? |
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Definition
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Term
True or False
Bone marrow and stem cell transplants are viable treatment options for many immune disorders? |
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Definition
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Term
True or False
Human infants are born lacking antibodies? |
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Definition
True.
The only immunoglobulin that crosses the placental barrier and transfers immunity is IgG |
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Term
Fill-in-the-Blank
Autoimmune diseases arise from the failure of self- |
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Definition
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Term
Fill-in-the-Blank
Type I allergic reactions are mediated by ________ class immunoglobulins. |
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Definition
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Term
Fill-in-the-Blank
Disorders of the __________ system compromise the effectiveness of the innate immune system. |
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Definition
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Term
Fill-in-the-Blank
______ disorders are characterized by the excessive or inappropriate activation of the immune system. |
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Definition
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Term
Fill-in-the-Blank
Allergic reactions are often characterized as either anaphylactic (systemic) or ________ (local). |
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Definition
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Term
True or False
HIV infection can be spread from the mother to child by breast feeding? |
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Definition
True.
Transmitted through blood, semen, vaginal fluids, and breast milk. |
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Term
True or False
Sexual contact is no longer the primary mode of transmission for HIV infection? |
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Definition
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Term
True or False
All individuals, apart from children and older adults, should be regularly screened for HIV infection? |
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Definition
True.
All individuals 13-64 years of age should be routinely screened for HIV. |
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Term
True or False
HIV is able to use the DNA of immune cells to replicate itself?
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Definition
True.
In order for HIV to reproduce, it must change its RNA into DNA. It does this by using the reverse transcriptase enzyme. Reverse transcriptase makes a copy of the viral RNA, and then in reverse makes another mirror-image copy. The result is a double-stranded DNA that carries instructions for viral replication. |
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Term
True or False
HIV infection is associated with the development of several specific types of cancer?
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Definition
True
AIDS has a higher incidence of certain malignancies, especially Kaposi sarcoma, non-hodgkin lymphoma, and noninvasive cervical carcinoma. |
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Term
Fill-in-the-Blank
HIV damages the immune system by taking over and destroying _________ lymphocytes. |
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Definition
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Term
Fill-in-the-Blank
_______ sarcoma is the most common malignancy related to HIV infection? |
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Definition
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Term
Fill-in-the-Blank
A common respiratory manifestation of HIV is P. jiroveci _________. |
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Definition
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Term
Fill-in-the-Blank
Highly active ________ therapy (HAART), typically comprising a combination of 3 to 4 agents, has become the current standard of care for HIV. |
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Definition
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Term
Fill-in-the-Blank
The mycobacteria that cause _________ are responsible for the most deaths of people with HIV infection worldwide. |
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Definition
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Term
| Which type of immune system is characterized by the development of a specific response to an antigen? |
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Definition
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Term
True or False
The function of MHC molecules is to mark foreign proteins, rendering them from antigenic? |
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Definition
False
The MHC molecules are used by the immune cells to differentiate host tissue from foreign tissue. They are found on all host tissues. |
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Term
| The aging immune system is less responsive due to? |
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Definition
| Decline in immune responsiveness, decrease in the size of the thymus gland, biological clock in T cells, and altered responses of the immune cells to antigen stimulation. |
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Term
| Which hypersensitivity reaction can be treated with administration of epinephrine? |
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Definition
Type I
these reactions are anaphylactic; thus airway constriction is a major concern. Epinephrine stimulates airway relaxation. |
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Term
True or False
Immunodeficiency disorders arise only later in life and are associated with viral infectons? |
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Definition
False
Many immunodeficiency disorders are congenital |
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Term
| Which cell type is most problematic in the development of AIDS? |
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Definition
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Term
True or False
Infections that occur in AIDS patients are the direct result of viral activity? |
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Definition
True
HIV virus kills immune cells, providing ample opportunity for infection |
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Term
| The sign and symptoms of an AIDS infection are due to? |
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Definition
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Term
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Definition
Classified as hyperacute, acute, and chronic.
Hyperacute: occurs almost immediatley after transplantation. Acute: occurs within the first few months after transplantation and is evidenced by signs of organ failure, months or years later after immunosuppression has been used and terminated. Chronic: over a prolonged period, manifests with dense intimal fibrosis of blood vessels of the transplanted organ. |
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Term
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Definition
| Failure of an organism in recognizing its own constituent parts as self, which allows an immune response against its own cells and tissues. |
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Term
| Type I Immediate Hypersensitivity Disorders |
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Definition
| Results from exposure to an environmental allergen, it is mediated by IgE that leads to the release of inflammatory mediators for sensitized mast cells. Typically involves repeated exposure to the allergen to cause sufficient production of IgE to sensitize and produce an allergic response. Begin rapidly, often within minutes. Referred to as allergic reactions. Cells: type 3 helper and mast cells (tissue cells) or basophils (blood cells). |
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Term
| Type II Antibody-Mediated Disorders |
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Definition
| Results from the interaction of an antigen with an antibody, and is mediated specifically by IgG or IgM. These antigens are usually on the surface of cells. Usually complement is activated and causes destruction of the antigen along with the tissue, or the antigens can cause an inflammatory response instead, which can also damage tissue. Involve humoral antibodies against cell surface or extracellular matrix antigens that result in complement-mediated phagocytosis or inflammation and cell injury, or in some cases, abnormal physiologic responses without cell injury. |
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Term
| Type III Immune Complex-Mediated Disorders |
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Definition
| Involves a problem with the body getting rid of antigen-antibody complexes. These complexes are formed when antibodies attach to antigens-they may sometimes be deposited in tissues or stay in the plasma and this sets up an inappropriate inflammatory response. This means that tissue that is normal is injured due to the inflammatory response. Result in generation of circulating immune complexes in which humoral antibodies bind antigen and activate complement. The fractions of complement attract inflammatory cells that release tissue-damaging products. |
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Term
| Type IV Cell-Mediated Hypersensitivity Disorders |
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Definition
| Mediated by the cells-therefore the response is usually delayed for up to 72 hours. This type occurs in response to an antigen that enters the cell; the T lymphocytes damage the cell in an effort to kill the antigen, and sometimes this reaction can cause disease rather than prevent it. Two basic types: direct and delayed. |
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Term
| Immunodeficiency Primary Disorders |
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Definition
Congenital or inherited abnormalities of immune function that render a person susceptible to diseases normally prevented by an intact immune system. B cell disorders: impair the ability to produce antibodies and defend against microorganisms and toxins that circulate in body fluids (IgM and IgG) or enter the body through the mucosal surface of the respiratory tract or GI (IgA). Prone to pyogenic infections due to the encapsulated organisms.
T cell disorders: impair the ability to orchestrate the immune response (CD4 helper cells) and protect against fungal, protozoan, viral, and intracellular bacterial infections (CD8 cytotoxic cells). Surveillance against oncogenic viruses and tumors, increase risk for cancers.
Combined B & T cell disorders: life-threatening absence of immune function that requires bone marrow or stem cell transplantation for survival. |
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Term
| Immunodeficiency Secondary Disorders |
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Definition
Aquired later in life. Result of malnutrition; disseminated cancers; infection of the cells of the immune system (HIV); etiologic agent of AIDS; and treatment with immunosuppressive drugs (corticosteroids or transplant rejection meds). Humoral: consequence of conditions that increase immunoglobulin loss, diseases that decrease immunoglobulin production, or drug induced states that cause a decrease in immunoglobulin levels. Can result from chronic lymphocytic leukemia, lymphoma, and multiple myeloma.
Cell-mediated: more common that primary, described in conjunction with acute viral infection (measles), hodgkins, other lymphomas. |
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Term
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Definition
Primary infection phase: acute phase may include fever, fatigue, myalgias, sore throat, night sweats, GI problems, lymphadenopathy, maculopapular rash, and headache. S/S occur 1-4 weeks after exposure, 7-10 duration.
Chronic asymptomatic or latency phase: no S/S of illness; median time of latent period of 10 years. CD4 cells fall from range of 800-1000 cells to 200 or lower.
Overt AIDS phase: CD4 less than 200, or an AIDS defining illness; without antiretroviral treatment can lead to death in 2-3 years. |
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Term
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Definition
| Gamma globulin. Displays antiviral, antitoxin, and antibacterial properties, responsible for protection of newborn; activates complement and binds to macrophages. Can tag an antigen for recognition and destruction by phagocytes. Most abundant. Present in body fluids and readily enter tissues. Only one to cross placenta and can transfer immunity from mom to fetus. Protects against bacteria, toxins, and viruses. Can bind to target cells. |
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Term
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Definition
| Predominant Ig in body secretions; protects mucous membrane. Found in saliva, tears, colostrum, and bronchial, GI, prostatic and vaginal secretions. Primary defense against local infections in mucosal tissues. Prevents the attachment of viruses and bacteria to epithelial cells. |
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Term
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Definition
| Forms natural antibodies; prominent in early immune responses; activates complement. First to appear in response to an antigen and is the antibody type made by a newborn. Presence of IgM suggests a current infection in the infant by a specific pathogen. |
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Term
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Definition
| Found on B lymphocytes; needed for maturation of B cells. Serves as an antigen receptor for initiating the differentiation of B cells. |
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Term
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Definition
| Binds to mast cells and basophils; involved in combating parasitic infections, allergic responses, and hypersensitivity reactions (inflammation). |
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Term
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Definition
| Occurs when immunologically competent cells or precursors are transplanted into recipients who are immunologically compromised. Persons who have undergone allogeneic bone marrow transplatation, it may also follow transplantation or organs rich in lymphoid tissue (liver) or follow transfusions with nonirradiated blood. 3 requirements: transplant must have functional cellular immune component; recipient tissue must bear antigens foreign to the donor tissue; recipient immunity must be compromised to the point that it cannot destroy the transplanted cells. Acute reaction: occurs within days to weeks, involves the epithelial cells of the skin, liver, and GI tract. Chronic reaction: symptoms persist or begin 100 days or more after; skin lesions resembling systemic sclerosis. |
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