Some updates. Exam 1 Wednesday No LBL this week or class Friday (Steinmetz Symposium)! BNG Seminar TODAY! Outline for today

Transcription

1 The Immune System

2 Some updates Exam 1 Wednesday No LBL this week or class Friday (Steinmetz Symposium)! BNG Seminar TODAY! Lippman 017, Common Hour (w/ lunch) Julie Czupryna, Ph.D. Technical Director, Optical Imaging Core, Upenn Beyond the Knife: Noninvasive Imaging of Disease in Small Animals Outline for today Exam 1 additional example problem Acquired Immunity II

3 Example exam problem 1 (modified) H&E staining of MDMs exposed to HDPE particles for 24 h: (a) normal light; (b) polarized light. Original magnification x 100 (Note: takeaway portions removed!) Recall the result at left from LBL paper 2 a. What was the main result or takeaway from this figure? b. The cells were plated atop collagen (a protein). What are the other three types of biomacromolecules (hint: one of the other three that is not a true polymer is lipids; the other two types are polymers). c. Say the researchers wanted to make the PS particles less adhesive give an example of a general strategy they could try (hint: think of the properties of a surface that affect adhesivity to cells)

4 Example exam problem 2 (Above): Categories of morphological forms (Left): Relative frequency of each shape on pyrolytic carbon Recall the result at left from LBL paper 2 a. How would you describe the major takeaway or conclusion from this figure? b. Platelet response can be judged as a combination of 1) number of platelets adhered and 2) platelet morphology. Which species was most active for each category based on the data here? c. What is the difference between a platelet plug and a blood clot?

5 Immunogens, antigens, and antibodies Antigen Immunogen Pathogen viruses, bacteria introduced these last class Epitope Immunoglobulin (antibody)

6 Immunoglobulins (antibodies) 5 classes of immunoglobulins in humans (antibodies, Ab) Most Ab found in human blood are the IgG type Constitute 75% of plasma Ab Only Ab to cross placenta and circulate through the fetal blood We will focus on the IgGs

7 Immunoglobulins All classes of IgGs have heavy and light chains All heavy-light chains have variable and constant regions Antibody-antigen binding is very strong and sterically specific Light chain bonded to heavy chain with disulfide bonds Let s come back to Ab when we discuss humoral immunity in more detail

8 Immunity Introduction Acquired immunity has 2 subtypes Cell-mediated immunity arises from cytotoxic action of cells Humoral immunity from chemical activation of antibodies cell-mediated humoral

9 Cell-mediated immunity 1 Both cell-mediated/humoral immuity have the same initial stages

10 1. The macrophage as an antigen presenting cell (APC) Major histocompatibility complex (MHC)

11 Cell-mediated immunity 2 Both cell-mediated/humoral immuity have the same initial stages

12 2. Helper T-cell activation by APC

13 Cell-mediated immunity 3

14 3. Cytotoxic T-cell activation by APC cell-mediated immunity: specificity is toward the MHC in combination with the antigen (as we will see unlike humoral immunity)

15 Cell-mediated immunity 4 How does the activated cytotoxic T-cell destroy the APC?

16 4. APC targeting by activated cytoxic T-cell

17 Immunity Introduction Acquired immunity has 2 subtypes Cell-mediated immunity arises from cytotoxic action of cells Humoral immunity from chemical activation of antibodies cell-mediated humoral

18 Humoral immunity 1

19 B-cell activation

20 Humoral immunity 2

21 Memory versus plasma cells won t discuss these further let s look closer at these

22 Plasma cell Ab production Plasma cells are differentiated, mature B- lymphocytes that produce large volumes of Ab! Also called plasma B cells, plasmocytes or effector B cells

23 Antibody contributions to immunity Ab contribute to immunity through two primary mechanisms activation of the complement system activation of effector cells

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