IMMUNOLOGY QUIZZES FROM LECTURE 1-11
Infection of macrophages with intracellular bacterial pathogens (e.g. Listeria monocytogenes) that escape from the phagosome to the cytoplasm results in the stimulation of:
Cell-mediated immunity
A patient is identified who has a severe bacterial infection that is NOT accompanied by increased neutrophils at the site of infection. The likely defect is in production of:
Chemokines
Chemokines are molecules that
Direct inflammatory cells to the site of infection
The process of opsonization contributes to the elimination of pathogens by
Enhancing phagocytosis An opsonin is something that "coats" microorganism and in doing so, targets it for destruction by phagocytes. This process is referred to as opsonization.
An investigator is testing a new topical antibiotic ointment. When she incubates the drug with B cells in vitro, no B cell activation is induced. She moves onto in vivoexperiments where she applies the ointment to the skin of mice. To her surprise, the mouse develops a rash. Histological examination of the tissue shows an excess of activated lymphocytes. In addition, serological assays reveal antibodies towards self proteins in the skin. In this scenario, the antibiotic is acting as a (an): Lecture 9 antigens and receptors, Slide 19-23
Hapten - Haptens are antigens that don't active lymphocytes, just like in the in vitro B cell experiment. When they fuse to a carrier, like a human protein, they become immunogenic and activate antigen receptors, like in the mouse experiment
Which of the following cytokines is produced in response to the recognition of viral RNA and induces the expression of enzymes that block viral replication? Lec 6: Cytokines of the Innate Immune Response Slides 18-21
IFN-alpha Type I interferons (IFN-α and IFN-β) are produced by virally-infected cells by the recognition of viral PAMPs (i.e. dsRNA), by pattern recognition receptors, such as RIG-1. Type I interferons bind to receptors on neighboring uninfected cells and induce expression of genes whose products interfere with viral replication. Type I interferons also bind to receptors on infected cells and induce expression of genes whose products enhance the cell's susceptibility to CTL-mediated killing (i.e. MHC class I).
Which of the following best describes the differences between the classic and alternate complement pathways?
The alternate pathway typically requires C3b for activation, while the classical pathway typically requires antigen-antibody complexes.
B-cell lymphomas in mice, when experimentally treated with anti-idiotype sera, show regression. However, they frequently recur and now show no reactivity with the same anti-idiotype sera. Likely explanation(s) for this change could be:
A loss of surface Ig receptor on the B-lymphoma cells.
An efficient immune mechanism to overcome infection with extracellular bacteria is:
A. Fc Receptor-mediated phagocytosis
Activation of the complement cascade plays an important role in host defense by all of the following:
A. working via the classical pathway, together with antibody, to induce bacteriolysis. B. mediating bacteriolysis directly, via the alternative pathway, in the absence of specific antibody. C. facilitating phagocytosis by generating opsonins. D. attracting phagocytes to the site of an infection by generating chemotaxins.
You are an immunologist specializing in pediatric immunodeficiencies. You have just been referred a patient who is suspected of having x-linked agammaglobulinemia (XLA). In this disease, the development of CD19+ cells is interrupted resulting in a the failure to produce mature cells of this phenotype. A lymph node biopsy from this patient is most likely to reveal:
Absent follicles and germinal centers - Primary and secondary follicles (with germinal centers) are sites with lots of B cells Lecture 7 tissues and organs, Slides 22-25
A previously healthy 3-year-old boy is infected with an upper respiratory tract virus for the first time. During the first few hours of infection, which one of the following events occurs?
An immune response dominated by neutrophils and monocytes keeps the infection under control The innate immune response is in place prior to infection and is active early in infection Lecture 1, slides 14-15
Which of the following correctly describes the structure or function of the antigen receptors found in B and T lymphocytes?
B cell receptors have 2 heavy and 2 light chains The BCR or antibody protein is Y-shaped and made up of 2 identical heavy chains and 2 identical light chains that use hydrogen and disulfide bonds to organize into a tetramer. Lecture 9 antigens and receptors, slides 6-8
You see a young man in the later stages of HIV infection with a markedly decreased CD4+ T-cell count, diarrhea and weight loss, fever and oral candidiasis. Which one of the following is NOT necessarily an anticipated infection in this man?
Bacterial pneumonia.
A 2-year-old male presents with a history of repeated cases of viral pneumonia and viral gastroenteritis. Which of the following components of their immune system is most likely to be defective?
Beta2 Microglobulin - This is a component of the MHC-I molecule Lec 10 MHC, slide 11
Which of the following statements correctly describe the "co-dominance" feature of MHC genes?
Both the maternal and paternal alleles of each MHC gene are expressed - Co-dominant expression will ensure the greatest amount of antigens can be presented Lec 10 MHC, Slide 17-18
The innate immune response against bacteria may be initiated by recognition of certain broad structures on microbial surface by Pathogen Recognition Receptors (PRRs). The broad structures are:
C) PAMP (Pathogen-Associated Molecular Patterns)
Which of the following complement components is integral to the ability of the complement pathways to eliminate pathogens due to its role in enhancing phagocytosis of microbes?
C3b C3b, which is formed during all 3 complement pathways, coats the surface of microbes and acts as an opsonin. Phagocytes such as monocytes/macrophages and neutrophils express a receptor (CR1) that can bind C3b allowing these cells to more efficiently phagocytose microbes. Lecture 5: Complement Slide 26
Repeated infections with Neisseria meningitidis in a patient should raise physician concern for which of the following underlying conditions?
C5-C9 deficiency Complement proteins C5-C9 make up the membrane attack complex, the terminal component of all 3 complement pathways. A deficiency in any one of these proteins will result clinically in a susceptibility to repeated Neisserial infections. Lecture 5: Complement Slide 32
17. Systemic Lupus Erythematosus (SLE), is characterized by immune complexes in serum and the basement membranes of many organs and joints. This involves Polyclonal B-cell activation resulting in increased production of IgM and IgG, which activate complement. Which of the following complement proteins functions as a chemotactic attractant for neutrophils, as well as an anaphylatoxin?
C5a
If the goal of immunotherapy is to eliminate all T lymphocytes, an effective treatment would utilize humanized monoclonal antibodies against:
CD3
A 6-year-old female presents to the pediatricians office with a 1-day history of fever, watery diarrhea, and headache. The parents reveal the child had ingested unpasteurized cheese one day prior to the start of symptoms. The diagnosis of gastroenteritis caused by the intracellular bacteria, Listeria monocytogenes is made. Which of the following responses are key to the elimination of this intracellular pathogen?
Cell-mediated immunity - Cell-mediated immunity is important for the clearance of intracellular microbes and is mediated by T cells Lecture 1, slides 30-32
You have a patient who makes autoantibodies against his own red blood cells, leading to hemolysis. Which one of the following mechanisms is MOST likely to explain the hemolysis?
Complement is activated, and membrane attack complexes lyse the red cells.
A 66 year old male is brought to the emergency department from a homeless shelter. He presents with fever and severe cough that kept him and others up all night at the shelter. His pulse is rapid, and other symptoms are consistent with bacterial pneumonia. The innate effector mechanism most likely to act together with his early IgM antibody production against the bacterial pathogen is:
Complement-mediated opsonization
A 19-year-old college student inhales influenza viral particles after coming in close contact with someone in the library seconds after they sneezed. Fortunately, she does not become ill. All of the following may have provided protection to pathogens at the mucosal epithelium EXCEPT:
Constitutive presence of neutrophils in the epithelial tissue - That's right. Neutrophils are not constitutively present in mucosal epithelium. They are recruited to the tissue in response to the inflammatory signals induced by binding of PAMPs to PRRs. Lecture 3: Epithelial Barriers and Innate Recognition Slides 11-19, 24-25
Three- year-old Johnny gets burned in a home accident and requires extensive skin grafting. The attending physician believes that Johnny will tolerate the graft with little, (or no) immunosuppressive drugs since the child has an immunodeficiency disorder. Johnny most likely has:
DiGeorge's Syndrome
A 24-year-old primigravida after an uneventful pregnancy delivered a male baby at term. Upon neonatal examination, the baby was found to have low set ears, microcephaly (small head), rock bottom feet, cynosis (bluish discoloration) of the body due to severe congenital anomaly of the heart. Within 24 hours, the child died of severe hypocalcemic convulsions. Autopsy findings revealed redimentary thymus, total agenesis of parathyroid glands and severe ventricular and atrial defects of the heart. Based on the history, what is the most presumptive diagnosis?
DiGeorge's syndrome
A child running along the sidewalk falls and scrapes his knee, and the abrasion subsequently gets infected. The bacterial antigens from the infected skin will most directly stimulate an adaptive immune response in the:
Draining lymph node The lymphatics is what drains lymph fluid from tissues to their draining lymph nodes (secondary lymphoid organ) to concentrate antigens with immune cells and better allow for adaptive immune activation Lec 7 organs and tissues, Slides 16-21
A patient walks into your clinic complaining of a chronic cough and general fatigue. Upon examination you diagnose him to have small cell lung cancer. Since the patient has a very aggressive form of cancer, that has been unresponsive to medication or radiation, you decide to enroll him in a new clinical trial that is using gene therapy to treat lung cancer. The theory behind the trial is to use gene therapy to express a protein on the cell surface that will stimulate T-cell proliferation upon immune surveillance of the tumor cells. Which of the following would be the most effective co-stimulatory protein to be expressed on the tumor cell in this clinical trial?
E. CD80/CD86
A 18-year-old female presents with a 2-day history of fever (103.1 F), malaise, nasal congestion, and cough. A rapid influenza virus test performed in the office returns a positive result. Peptides derived from newly synthesized viral protein will be loaded onto MHC molecules in which of the following locations?
Endoplasmic reticulum Viruses are cytoplasmic and MHC-I peptides are loaded into the antigen binding groove in the ER lumen Lec 11 Ag processing and presentation, Slide 21
A 65 year old male with lymphoma is treated with chemotherapy for his malignancy. Not long after this he develops a lung infiltrate and a severe cough. Analysis of chest x rays suggests reactivation of latent tuberculosis. What glycoprotein on macrophages presents mycobacterium antigens to helper T cells in this patient?
HLA-DR - This is an MHC-II allele Lec 10 MHC, slide 13
An adult patient is admitted to the Intensive Care Unit and diagnosed with septic shock. The hospital staff offers a new experimental treatment using monoclonal antibodies as part of a clinical trial. The goal of the treatment is to block inflammatory cytokines that mediate the negative and dangerous reactions in septic shock such as increased vascular permeability. Which mediators are the targets of this treatment?
IL-1 and TNFα
A young woman with acute myeloblastic leukemia is treated with intensive chemotherapy, followed by a bone marrow transplant. Which of the following cytokines would be expected to stimulate lymphoid cell development from stem cells in the grafted bone marrow?
IL-7
A 6-year-old boy injures his foot when he accidentally steps on a rusty nail in his backyard. Which of the following chemoattractants is secreted from the site of injury and which cells are recruited first into the damaged tissue in response to this chemoattractant?
IL-8 and neutrophils IL-8 (CXCL-8) is secreted by tissue macrophages and acts as chemoattractant for neutrophils, the first leukocytes to be recruited to the site of inflammation. Lec 4: Recruitment and Activation of the Cellular Innate Response Slides 10-28
A 2-year-old male presents with a history of repeated bacterial pneumonias by encapsulated bacteria and skin abscesses. In which of the following would you expect to see a defect?
Igα/Igβ Igα/Igβ is the signaling co-receptor of B cell receptors and contain the ITAM domains to initiate phosphorylation. Humoral immunity is crucial for clearance of encapsulated bacteria Lecture 9 antigens and receptors, Slide 8
MHC-I presentation is a major component of the immune system's response to virus infection. It is therefore no surprise that many viruses have developed mechanisms to interfere with the MHC class I pathway. This interference is most likely to include which one of the following?
Inhibit proteosome function - The proteasome is the start of the MHC-I pathway Lec 11 Ag processing and presentation, Slide 28
Recruitment of the cellular mediators of innate and adaptive immunity is heavily influenced by the production of chemokines in the local environment. Which of the following molecule(s) is most directly influenced by the presence of chemokines and is key for the successful recruitment of cellular mediators to sites of inflammation? Lec 4: Recruitment and Activation of the Cellular Innate Response Slides 19-21
Integrins Chemokines, produced by activated macrophages and endothelial cells induce changes in the conformation of the integrins (LFA-1, Mac-1, VLA-4) on the surface of the leukocytes from a low affinity state to a high affinity state allowing for binding to integrin ligands (ICAM-1, VCAM-1) on the endothelium and firm adherence to the endothelial surface.
A 6-year-old boy is brought to a new school for the first time. Previous exposure Mycobacterium tuberculosis is assessed using the tuberculin skin test. The test is given by injecting a small amount of purified tuberculin protein underneath the skin, followed by a period of observation. In this case, two days after the test is given a 12-mm induration is observed (positive result), and the boy is referred to a health care practitioner for additional testing. Which of the following is most likely to be uniquely involved in elicitation of the observed reaction in this test?
Loading of tuberculin antigen onto MHC molecules in vesicles bound for the cell surface The injected protein is an extracellular antigen that will enter the MHC-II pathway Lec 11 Ag processing and presentation, Slide 19
An infant child is brought to the pediatrician for the evaluation of recurrent infections. The mother reports that her child has been having frequent respiratory and skin infections. The mother is not aware of any diseases that run in the family that could result in an increased susceptibility to infection. A CBC is ordered, and while total lymphocyte count is normal, it is noted that the CD4:CD8 ratio is 10:1 (normal is 2:1). Further genetic testing shows the infant has a mutation in the tapasin protein. What is the most likely diagnosis?
MHC Class I deficiency - Fewer CD8 cells would imply lower levels of MHC-I expression and therefore defects in maturation of CD8 T cells in the thymus Lec 11 Ag processing and presentation, Slide 21
A patient's throat was colonized with Streptococcus pyogenes, the causative agent of "strep throat." Some of the proliferating bacteria encountered a host cell which then released pro-inflammatory cytokines including IL-6 and tumor necrosis factor (TNF)-alpha. What kind of cell was it?
Macrophage
A 28-year-old woman presents to the ER with a deep laceration on her left hand. Patient states she sustained the injury while dicing vegetables. The wound is cleaned and sutured. Examination of the site of injury 5 days later reveals and abundance of cells secreting IL-1, TNF-alpha, and producing reactive oxygen species. Name these cells.
Macrophages Macrophages have 3 major functions; engulf and kill pathogens, secrete inflammatory cytokines, and present antigens. Upon recognition of pathogens via PRR, macrophages will be induced to secrete pro-inflammatory cytokines. In addition, pathogens engulfed via endocytosis will enter phagosomes and will be destroyed when those vesicles fuse with lysosomes containing reactive oxygen species (ROS). Lec 4: Recruitment and Activation of the Cellular Innate Response Slides 43-50
A 3-year-old child who is up to date on vaccinations steps on a rusty nail harboring spores of the bacterial pathogen Clostridium tetani, and the protective effects of the vaccine prevent her from developing tetanus. Which of the following features of adaptive immunity is being demonstrated here?
Memory The adaptive immune system forms long-lived memory cells that allow for rapid and enhanced responses upon the 2nd or subsequent exposures to a pathogen or vaccine antigens. Lecture 2, slides 10-11
A father brings his 3-year-old son to the pediatrician because he is concerned about his health. He states that throughout his son's life he has had recurrent infections despite proper treatment and hygiene. Upon reviewing the patient's chart, the pediatrician notices that the child has been infected multiple times with S. aureus, Aspergillus, and E. coli (all catalase + organisms). Which of the following most likely defective in this patient?
NADPH oxidase This patient is presenting with chronic granulomatous disease (CGD). This is caused by a mutation in the NADPH phagocyte oxidase enzyme which disrupts the production of ROS resulting in recurrent infection with catalase producing bacteria leading to the formation of granulomas. Lec 4: Recruitment and Activation of the Cellular Innate Response Slides 46-48
A 3-year-old boy has a history of repeated pyogenic (pus-forming) infections. He had normal antibody responses following childhood immunizations and normal recovery from chickenpox and measles. Decreased numbers or functional defects in which of the following cells best explains the cause of his infections?
Neutrophils
A 3-year-old boy has a history of repeated pyogenic (pus-forming) infections caused by extracellular bacteria. He had normal antibody responses following childhood immunizations and normal recovery from viral infections by chickenpox and measles. Decreased numbers or functional defects in which of the following cells best explains the cause of his infections?
Neutrophils Neutrophils are important for the phagocytosis and destruction of extracellular microbes Lecture 1, slide 19
A mother brings her 9-month-old son to the pediatrician for another respiratory tract infection. This infant has had a long history of infections. After birth, he had delayed separation of the umbilical cord stump and has already suffered multiple episodes of otitis media, and pneumonia. Analysis of blood leukocytes reveals a lack of expression of CD18. Which of the following most accurately describes the functional defect of the patient's immune system? Lec 4: Recruitment and Activation of the Cellular Innate Response Slides 30-32
Neutrophils are unable to traffic to infection sit This patient is presenting with leukocyte adhesion deficiency (LAD). It is caused by a mutation in the CD18 gene. CD18 is one chain of the heterodimer that makes up the LFA-1 and Mac-1 integrins. This means leukocytes such as neutrophils and monocytes are unable to tightly adhere to the endothelium which prevents extravasation into the tissue. Clinically, this will present early in life with recurrent bacterial and fungal infections. Delayed separation of the umbilical cord is a big buzz phrase for LAD.
Toll-like receptors located in endosomal membranes of cells recognize which of the following?
Nucleic acids - Endosomes contain TLRs that recognize nucleic acid from ingested microbes. (e.g. TLR-3, -7, -8, -9) Lecture 3: Epithelial Barriers and Innate Recognition Slides 24-26, 29-31
A 1-year-old boy with recurrent infections comes to the clinic for evaluation. He has a history of multiple systemic fungal infections. Upon examination, the child is found to demonstrate subclinical hypocalcemia, and history is notable for a surgery 6-months-ago to fix his cleft palate. A chest x-ray reveals the absence of a thymus. This disorder would affect cells predominantly residing in what part of the lymph node?
PARACORTEX - The patient has DiGeorge syndrome, so lacks T cells. The lymph node paracortex is where DCs present antigen to naive T cells. Lec 7 organs and tissues, Slides 22-24
A new employee in the SPCA was bitten by a rabid dog. The worker was brought to the Emergency Department even though he had been inoculated for tetanus, only three days before he was bitten. The attending physician ordered treatment with anti-rabies immune human globulin. Which one of the following describes the type of immunization the patient received in the emergency unit?
Passive artifical immunity.
A new employee in the SPCA was bitten by a rabid dog. The worker was brought to the Emergency Department even though he had been inoculated for tetanus, only three days before he was bitten. The attending physician ordered treatment with anti-rabies human immunoglobulin. Which one of the following describes the type of immunization the patient received in the emergency unit?
Passive immunity Passive immunity is derived from the transfer of protective antibody to a patient without any antigens that would activate the B or T cells of the adaptive immune response (active immunity) Lecture 1, slides 40-41
Peripheral blood monocytes are isolated from a patient suffering from a bacterial infection. Upon analysis, it is found that the monocytes express an induced gene coding for an enzyme required for intracellular killing. The enzyme is:
Phagocyte oxidase
Which of the following statements below correctly describes MHC Class II
Presents antigen that has been phagocytosed - Extracellular peptide antigens that are phagocytosed by APCs Lec 11 Ag processing and presentation, Slide 19
Which of the following systemic affects of the inflammatory cytokines, IL-1, TNF-alpha, and IL-6 contribute to the elimination of pathogens by opsonization? Lec 6: Cytokines of the Innate Inflammatory Response Slides: 10-12
Production of acute phase proteins by the liver - CRP and MBL are two acute phase produced by the liver in response to pro-inflmmatory cytokines. C-reactive protein (CRP) binds to phosphocholine on the surface of bacterial surfaces and mannose binding lectin (MBL) binds to carbohydrates on bacterial surfaces. Both act as opsonins enhancing phagocytosis by phagocytes.
A 4-year-old male presents to the office with a 2-day history of congestion, cough, fever, and lethargy. A rapid flu test conducted in the office comes back positive for influenza A virus. The fever in this patient was most likely induced by recognition via which of the following receptors?
RIG-1 in the cytoplasm of the infected host cell - Viruses infect by "injecting" their genomic material (DNA or RNA) into the cytoplasm of the host cell. RIG-like receptors located in the cytoplasm bind to viral RNA and activate an antiviral innate immune response. Lecture 3: Epithelial Barriers and Innate Recognition Slides 23-26
A drug that blocks the function of the chemokine receptor CCR7 would result in which of the following abnormalities?
Reduced numbers of T cells in lymph node Naive T cells express the chemokine receptor CCR7 to 'sense' for the presence of chemokines CCL19 and CCL21 which are produced in the lymph node paracortex and allow for firm adhesion to the HEV and entry to the lymph node Lecture 8 trafficking, Slide 15
You are working as a research and development scientist at a pharmaceutical company and have stumbled upon a drug that results in the retention of T cells in the lymph nodes. Which of the following interactions may this drug be disrupting accounting for the observed effect?
S1P:S1PR - S1P ligand is a higher concentrations in blood and lymph fluid compared to inside the LN. Naive lymphocytes enter the LN with low S1PR levels, which will slowly increase until it reaches a level where the S1P higher levels near the efferent 'pulls' the lymphocyte toward the exit and into the next LN where the process repeats Lec 8 trafficking, slide 26
A graduate student is interested in studying the features of immature, non-activated dendritic cells. In which of the following locations is she most likely to find them?
Skin Immature DCs are skin residents and sense PAMPs or inflammatory cytokines to activate. Then they will gobble up antigen and go to the lymph nodes to present Ag Lecture 8 trafficking, Slides 10-15
A 13-year-old female presents to her primary care physician for follow-up care of her recently diagnosed hereditary spherocytosis. She reports increasing fatigue and shortness of breath. Laboratory testing is significant for an elevated reticulocyte count and serum bilirubin. A decision has been made among the patient, her family, and physician to undergo an elective splenectomy. This surgery puts this patient at elevated risk for which of the following infections?
Streptococcus pneumoniae, an encapsulated bacteria The spleen has lots of macrophages which are important for clearing opsonized microbes out of the bloodstream and the splenectomy patient is highly susceptible to encapsulated bacteria Lec 7 organs and tissues, slide 29
A 2-year-old boy is referred to a specialist after a series of severe and lengthy infections. Physical exam indicates the child is below 20% for both height and weight. Blood work reveals the patient to be deficient in CD19+ cells. Which of the following capabilities would this child's immune system lack?
The production of antibody against extracellular pathogens CD19 is a marker for B cells which provide humoral immunity. Know your major CD markers we will identify cells by them! Lecture 1, slide 30 Lecture 2, slides 18-21
Sam, a ten month old child, has recurrent bacterial infections, but not viral infections. Tests show few circulating B cells. This is consistent with
X-linked agammaglobulinemia.
A 6-year-old boy is brought to a new school for the first time. Previous exposure Mycobacterium tuberculosis is assessed using the tuberculin skin test. The test is given by injecting a small amount of purified tuberculin protein underneath the skin, followed by a period of observation. In this case, two days after the test is given a 12-mm induration is observed (positive result), and the boy is referred to a health care practitioner for additional testing. The antigen binding groove of the MHC molecule principally involved in eliciting this response is formed by the....
alpha chain and beta chain - The MHC-II molecule is an alpha/beta heterodimer Lec 11 Ag processing and presentation, Slide 21
An antibody directed against the idiotypic determinants of a human IgG antibody would react with:
an IgM antibody produced by the same plasma cell that produced the IgG.
In mice, the MHC is designated H-2 and specific haplotypes are designated by letters. Thus, H-2b and H-2k are distinct haplotypes that have no MHC alleles in common. Homozygotes are specified as b/b, and k/k, heterozygotes as b/k (mixture of b and k MHC alleles). If an H-2 b/b mouse is immunized with influenza virus, and activated CD8 T cells are later extracted from a lymph node and tested in vitro, these cells will show strong, rapid killing of
cells from an H-2b/k mouse, infected with influenza virus. - The immunized mouse CD8 T cells will only recognize antigen presented in H-2b MHC molecules Lec 10 MHC, slide 7
You prescribe penicillin for your patient. The patient develops a severe allergic reaction and dies. In this case, the penicillin molecule was probably acting as a (an):
hapten.
A 4-year-old child suffering from repeated pyogenic infections was found to have normal phagocytic function and cell mediated immune responses. Lymph node biopsy would probably reveal:
lack of plasma cells.
With reference to the clonal selection theory, the following are true EXCEPT:
lymphocytes bear multipotential receptors which become specific after contact with antigen.
The basis for the control which MHC molecules have over the immune response is best explained by the:
need for antigen-derived peptides to bind an MHC class I or class II molecule for proper presentation to the receptor of a T lymphocyte.
A new drug that blocks the function of C5a has been developed for use in the treatment of vasculitic diseases caused by deposition of immune complexes. Which of the following physiological effects would be disrupted by use of this drug?
recruitment of neutrophils C5a is also known as an anaphylotoxin. It is generated in all 3 complement pathways when C5 is cleaved by the C5 convertase. Its functions include recruitment of inflammatory mediators like neutrophils and monocytes, activation of the vascular endothelium, and mast cell activation. Lecture 5: Complement Slide 27-28
