INTRODUCTION TO IMMUNOLOGY

Question 1

EXAMPLES OF WHEN HUMANS ARE STERILE?

Answer 1

THE ZYGOTE IS STERILE

WHEN INSIDE THE AMNIOTIC SAC, WE ARE STERILE

Question 2

ROLE OF THE IMMUNE SYSTEM?

Answer 2

MAINTAINS THE HOST IN A HEALTHY HOMEOSTASIS WITH THE ENVIRONMENT, PROTECT AGAINST INFECTION, TUMOUR FORMATION ETC.

Question 3

WHAT IS A SYSTEM?

Answer 3

A GROUP OF INTERACTING OR INTERRELATED ELEMENTS THAT ACT ACCORDING TO A SET OF RULES FROM A UNIFIED WHOLE
- RELY ON FEEDBACK LOOPS TO MAINTAIN A STABLE (FUNCTIONAL) STATE

Question 4

WHAT IS THE INNATE IMMUNE RESPONSE?

Answer 4

THE FAST, GENETICALLY ENCODED, MEMORYLESS RESPONSE (ALWAYS THE SAME, NO IMPROVEMENT/ADAPTATION)

Question 5

ONSET AND DURATION OF INNATE RESPONSE?

Answer 5

ONSET: MINUTES AFTER INFECTION
DURATION: UP TO A FEW DAYS

Question 6

WHAT IS THE ADAPTIVE IMMUNE RESPONSE?

Answer 6

IT’S A SLOWER, SELECTED ‘ON THE FLY’ IMMUNE RESPONSE WHICH HAS ‘MEMORY’

Question 7

ONSET AND DURATION OF ADAPTIVE IMMUNE RESPONSE?

Answer 7

ONSET: HOURS/DAYS AFTER THE INFECTION
DURATION: UP TO A FEW WEEKS

Question 8

MOST COMMON PLACE TO GET AN INFECTION?

Answer 8

MOUTH (DENTAL CARIES=)

Question 9

HOMEOSTASIS DIFFERENCES AMONG INDIVIDUALS?

Answer 9

• HEALTH HOMEOSTASIS ISN’T THE SAME FOR EVERYONE
• THRESHOLD FOR RESPONSE TO INFECTION DIFFERS
• THAT THRESHOLD IS VERY PLASTIC (NOT SET AT BIRTH, CAN CHANGE)

Question 10

WHAT IS IMMUNOLOGICAL MEMORY?

Answer 10

MAINTENANCE OF MEMORY B CELLS AND T CELLS AND HIGH SERUM OR MUCOSAL ANTIBODY LEVELS, STARTS DAYS TO WEEKS AFTER INFECTION ONSET, CAN BE LIFELONG

Question 11

WHAT TYPE OF REACTION CAN THE IMMUNE SYSTEM HAVE WHEN THERE’S BACTERIA IN THE BODY?

Answer 11

RESPOND OR TOLERATE (IMBALANCE IN THIS RESPONSE LEADS TO DISEASE)

Question 12

MAJORITY OF THE INFECTIONS ARE STOPPED BY WHICH MECHANISMS?

Answer 12

PHYSICAL BARRIERS AND INNATE RECOGNITION AND RESPONSE

Question 13

CAN THE ADAPTIVE IMMUNE RESPONSE BE INITIATED WITHOUT PRIOR INITIATION OF THE INNATE RESPONSE?

Answer 13

NO

Question 14

STEM CELL FROM WHICH THE CELLS OF THE IMMUNE SYSTEM COME?

Answer 14

MULTIPOTENTIAL HEMATOPOIETIC STEM CELL (HEMOCYTOBLAST)

Question 15

WHICH CELL DO ALL INNATE IMMUNE CELLS COME FROM?

Answer 15

COMMON MYELOID PROGENITOR

Question 16

WHICH CELL DO ALL ADAPTIVE IMMUNE CELLS COME FROM?

Answer 16

COMMON LYMPHOID PROGENITOR

Question 17

INNATE IMMUNE CELLS EXAMPLES:

Answer 17

THROMBOCYTE, MACROPHAGE, DENDRITIC CELLS, NEUTROPHILS, BASOPHILS, MAST CELLS, ERYTHROCYTES

Question 18

ADAPTIVE IMMUNE CELLS EXAMPLES:

Answer 18

T LYMPHOCYTE, B LYMPHOCYTE, PLASMA CELL, LARGE GRANULAR LYMPHOCYTE…

Question 19

TOPOLOGICALLY, HUMANS ARE A

Answer 19

CYLINDER

Question 20

SURFACES OF OUR BODY THAT MOST INTERACT WITH THE ENVIRONMENT ARE MOST LIKELY TO GET INFECTED, WHAT ARE THE EXAMPLES OF THESE SURFACES?

Answer 20

• RESPIRATORY, REPRODUCTIVE AND GI TRACT

- WOUNDS, ABRASIONS AND BITES THAT DISRUPT ANATOMICAL BARRIERS

Question 21

WHAT ARE IMMUNE PRIVILEGED SITES?

Answer 21

PARTS OF THE BODY WERE YOU WOULDN’T EXPECT TO GET AN INFECTION/MOST ANTIGENS CAN’T PRODUCE AN IMMUNE RESPONSE THERE
BRAIN (CNS), EYES, OVARIES AND TESTES

Question 22

PHYSICAL PROPHYLAXIS:

Answer 22

• EPITHELIAL SURFACES ARE THE 1ST ANATOMICAL BARRIER TO INFECTION (SKIN EPIDERMIS, GUT EPITHELIUM, BRONCHIAL CILIATED EPITHELIUM)
• CHEMICAL BARRIERS ARE ALSO PRESENT (LYSOZYME IN TEARS AND SALIVA, MUCUS, ACID IN THE STOMACH, ANTI MICROBIAL PEPTIDES…)

Question 23

INNATE CELLS ARE USUALLY PHAGOCYTIC, WHAT DOES THAT MEAN ABOUT THEIR FUNCTIONING?

Answer 23

THEY ‘EAT’ CELLS TO SIMPLY REMOVE THE MICROBE AND DESTROY IT

Question 24

WHAT ARE NEUTROPHILS?

Answer 24

SHORT LIVED BUT EFFECTIVE INNATE EFFECTOR CELLS THAT CAN MAKE EXTRACELLULAR TRAPS (NETs) FROM EXCRETED DNA TO CAPTURE BACTERIA

Question 25

HOW DO INNATE CELLS DETECT INFECTIOUS AGENTS?

Answer 25

THEY CAN DIRECTLY DETECT INFECTIOUS AGENTS THROUGH GENETICALLY ENCODED RECEPTORS CALLED 'SENSORS'

Question 26

WHAT ARE 'SENSORS' OF INNATE CELLS AND WHERE CAN THEY BE LOCATED?

Answer 26

SENSORS ARE PATTERN RECOGNITION RECEPTORS (PRRs) WHICH CAN BE MEMBRANE BOUND OR IN THE CYTOPLASM

Question 27

EXAMPLES OF MEMBRANE BOUND PATTERN RECOGNITION RECEPTORS (INNATE CELL 'SENSORS'):

Answer 27

TOLL LIKE RECEPTORS (TLRs) | C-TYPE LECTIN RECEPTORS (CLRs)

Question 28

EXAMPLES OF CYTOPLASMIC PATTERN RECOGNITION RECEPTORS (INNATE CELL 'SENSORS'):

Answer 28

NOD-LIKE RECEPTORS (NLRs) | RIG-I-LIKE RECEPTORS (RLRs)

Question 29

2 MAIN TYPES OF LYMPHOCYTES (WHITE BLOOD CELLS)

Answer 29

T CELLS AND B CELLS

Question 30

WHICH CELLS ARE THE GATEKEEPERS OF THE ADAPTIVE IMMUNE RESPONSE?

Answer 30

T CELLS

Question 31

WHERE DO T CELLS PRIMARILY DEVELOP?

Answer 31

THE THYMUS

Question 32

HOW DID THE T CELLS GET THEIR NAME?

Answer 32

T COMES FROM THEIR SITE OF PRODUCTION, THE THYMUS

Question 33

WHAT ARE THE ACTIVATED T CELLS CALLED?

Answer 33

EFFECTOR T CELLS

Question 34

FUNCTIONS OF EFFECTOR T CELLS:

Answer 34

- CAN BE CYTOLYTIC | - CAN LICENCE B CELLS TO ACTIVATE

Question 35

WHERE ARE B CELLS PRODUCED?

Answer 35

THE BONE MARROW

Question 36

WHAT DO B CELLS PRODUCE AND WHAT IS THE ROLE OF THIS PRODUCT?

Answer 36

- ANTIBODIES - THE ANTIBODIES HAVE HIGH AFFINITY FOR BINDING TO PATHOGENS AND THEY CAN BLOCK THEIR FUNCTION OR EXPOSE THEM TO INNATE RESPONSE FOR KILLING

Question 37

WHICH TYPE OF IMMUNE RESPONSE IS LACKING IN BABIES AND HOW DO THEY ACQUIRE ANTIBODIES?

Answer 37

ADAPTIVE RESPONSE | BREAST MILK IS A SOURCE OF ANTIBODIES

Question 38

ROLE OF T CELL ANTIGEN RECEPTORS (TCRs):

Answer 38

RECOGNISE SHORT PEPTIDES FROM PATHOGENIC PROTEINS

Question 39

ROLE OF B CELL ANTIGEN RECEPTORS (ANTIBODIES):

Answer 39

RECOGNISE PATHOGEN STRUCTURES

Question 40

T CELL AND B CELL ANTIGEN RECEPTORS: HOW ARE THEY FORMED?

Answer 40

- TCRs AND BCRs ARE NOT GENETICALLY ENCODED - THROUGH THE PROCESS OF SOMATIC GENE RECOMBINATION, ALMOST LIMITLESS POTENTIAL RECEPTORS CAN BE ENCODED, DEPENDING ON THE ANTIGEN

Question 41

HOW ARE RECEPTOR GENES CREATED (FOR T CELL AND B CELL ANTIGEN RECEPTORS)?

Answer 41

USING V(D)J SOMATIC RECOMBINATION, WHICH 'STITCHES' GENETIC FRAGMENTS TOGETHER TO CREATE A UNIQUE GENE

Question 42

HOW DO TCRs DIFFER AMONG T CELLS?

Answer 42

- ALMOST NONE HAVE THE SAME TCRs - EACH ONE IS A CLONOTYPE (a unique nucleotide sequence that arises during the gene rearrangement process for that receptor)

Question 43

WHICH ENZYMES INITIATE V(D)J SOMATIC RECOMBINATION DURING IMMUNE CELL DEVELOPMENT TO HELP LYMPHOCYTE ANTIGEN RECEPTOR CREATION?

Answer 43

RAG1/2 ENZYMES

Question 44

ACTIVATED T CELLS WHICH PROVIDE HELP TO OTHER IMMUNE CELLS (LIKE B CELLS) ARE CALLED:

Answer 44

HELPER T CELLS

Question 45

ACTIVATED T CELLS WHICH KILL INFECTED CELLS BY DIRECT RECOGNITION ARE CALLED?

Answer 45

CYTOTOXIC T CELLS

Question 46

WHAT IS THE MOLECULAR BRIDGE BETWEEN INNATE AND ADAPTIVE RESPONSE?

Answer 46

- PEPTIDES DERIVED FROM PATHOGENS ARE 'PRESENTED' ON SURFACE IN MHC COMPLEX - THE T CELL INTERACTION WITH PEPTIDE-MHC IS THE MOLECULAR BRIDGE BETWEEN INNATE AND ADAPTIVE RESPONSE

Question 47

ANTIBODY MEDIATED EFFECTOR (ACTIVATED LYMPHOCYTES) FUNCTIONS:

Answer 47

NEUTRALISATION (BLOCKING VIRUS ENTRY INTO CELLS OR BLOCKING TOXIN ACTION) OPSONISATION (COATING MICROBES TO ALLOW THEIR EFFICIENT UPTAKE) COMPLEMENT ACTIVATION (DIRECT LYSIS OF MICROBE)