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Unit 4: Blood and Lymph > BL - Immunomodulators > Flashcards

Flashcards in BL - Immunomodulators Deck (29)
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LO 1. Define monoclonal antibodies and describe how they are made.

mAbs: progeny Abs from a single B cell clone that has been fused with a multiple myeloma tumor cell (very specific to a certain target). Made from transgenic animals secreted into milk, or in transgenic plants


LO 2. Discuss the use of monoclonal antibodies as anti-inflammatory agents.



LO 3. Compare and contrast murine, chimeric, humanized, and human monoclonal antibodies. Which might have disadvantages when used in human patients and why?

murine: derived from mice (-omab)***
chimeric: mouse VL and VH with human C domain (-ximab)***
humanized: only CDRs of V domains from mouse (-zumab)***
human: (-umab)
*** non-human = possible problems?


LO 4. Define NK cells and ADCC. Discuss the effect of Class I MHC expression levels on susceptibility of target cells to CTL and NK cells, respectively. Describe the mechanism for ADCC.

NK cell = innate immunity; lymphocytes w/o VDJ genes; use ADCC (antibody-dependent cytotoxicity) to recognize IgG and induce apoptosis in infected cells. Not MHC-restricted like CTL-mediated killing.


LO 5. Discuss the use of growth factors in bone marrow transplantation.



LO 6. Describe how a monoclonal antibody against a T cell surface molecule could enhance the activity of a CTL.

ex: ipilimumab. Binds CTLA-4 and prevents its inhibitory signal, so CTLs are activated. Used in melanoma.


LO 7. Discuss the use of modified (drugs, isotopes) monoclonal antibodies in tumor diagnosis or therapy.

Abs to tumor-associated antigens can activate complement or ADCC; ibritumomab tiuxetan can be used to fluorescently ID and then treat tumors; ipilimumab is used to bind to VEGF


What is immunomodulation?

use of drugs to change the function of the immune system


Name the 7 categories of immunomodulators.

3. glucocorticoids
4. biological response modifiers
5. tumor-specific monoclonal Abs
6. other Abs
7. misc. drugs


What are biological response molecules?

substances that target cytokines, their receptors, cellular communication molecules, or signaling molecules


Biological response molecules can be ____, ____, ____, or ____.

antagonists; agonists; Abs; normal gene products


What is the main problem with mAbs?



How are mAbs made?

transgenic animals (secreted into milk) or transgenic plants


The typical mAb derives from _____ that has been fused with _____.

a single B cell; a multiple myeloma tumor cell


Abs from immunized mice are called _____ and end in ____.

murine; -omab


Abs that have mouse VL and VH domains but human C domains are called _____ and end in ____.

chimeric; -ximab


Abs that only have CDRs from the V domain from a mouse are called _____ and end in ____.

humanized; -zumab


Fully human Abs end in ____.



What are NK cells?

large granular lymphocytes (LGL) that do not have V(D)J genes; part of innate immunity


What does ADCC stand for?

antibody dependent cell-mediated cytotoxicity


What is the main distinguishing feature of ADCC?

NK cells kill w/o restriction to MHC


How does ADCC work?

IgG Ab binds to target cell
NK cell binds to the Fc end of the Ab (FcgammaR)
NK cell is activated and kills cell via apoptosis


How are passive Abs used to treat CA?

antibodies are made to tumor-associated antigens, which activate complement or ADCC or die via immunotoxins


What does BiTE stand for?

Bispecific T-cell Engager


How does BiTE work?

2 single-chain engineered antibodies, one against CD19 and one against CD3, bind to T cells in lymphoma and cause tumor cell death


What drug uses BiTE?

blinatumomab (Blincyto)


What does CAR stand for?

chimeric antigen receptor


How are CARs used to treat CA?

bind them to T cells removed from CA pts using lentiviruses, then replace the cells; this allows transformed CTLs to bind tumor targets with high affinity and specificity w/o MHC restriction


Name 8 major drugs used in organ transplantation and how they work.

1. azathioprine (decreased DNA synth. and mRNA transc.)
2. mycophenylate mofetil (same as azathioprine, less tox)
3. glucocorticoids (anti-inflamm)
4. cyclosporine A (decrease IL-2 production and lessen stim of T cells)
5. tacrolimus (synergizes with cyclosporine A)
6. sirolimus (rapamycin- binds FKBP-12 to inibit mTOR and T cell activation)
7. anti-thymocyte globulin (ATGAM)
8. mAbs (against CD3 and IL-2)