biol+3+humoral+response+lesson

Powerpoint presentation is below. I have also uploaded the animation at the bottom of the page(no sound though). Your questions from the "invaders must die" presentation are posted. Task: answer one of the questions and/or ask at least two further questions relating to the humoral response.Even though the animation includes the cell-mediated response (which we haven't covered in detail yet) some of you might want to have a go at dealing with the questions below that relate to this. [|Humoral Immune Response.ppt]


 * Questions raised in class **


 * Answer to above questions **

1. the yellow thing is the macrophage. 2. These are the ctytokines (signaling molecules) released by the red cells (T lymphocytes) which act as a warning 3. The red cells were T-lymphocytes and the black cells were B-lymphocytes (due to the Y-shaped protein they produced). More specifically the red cells were T helper cells and the black cells were B plasma cells. 4. yes, in order to signal the other lymphocytes that they have detected and engulfed something 'non-self'. 5. 6.the red cells (T helper cells) were activated when they came across the antigen presenting cell - the macrophage which had ingested the pathogen. Their role was to communicate with the other cells in order to coordinate a response and exterminate the macrophage. It also stimulates the production of B plasma cells to produce antibodies. 7.it was destroyed (broken down?) by the black cells (B-lymphocytes) via their antibodies produced in order to rid of the 'non-self' pathogen the macrophage had engulfed. - please correct me if im wrong! 8. Because a 'non-self' pathogen was detected (due to its antigens ) by the macrophage. Initially the red cells (T helper cells) recognized the antigen on the infected macrophage cell and called upon the B plasma cells to produce antibodies and destroy the infected macrophage

If a macrophage eats a bacteria that already has the antibodies attached to it,will it still present the antigens even though they have already been detected by the B-cells and antibodies? Essentially will the Macrophage still be destroyed once it has ingested the bacteria? MW
 * Further questions **

This is in relation to one of my answers to Q. FOUR above... do the pathogens have 'receptors' or are they 'antigens' (markers)? or, do the antigens kind of act as receptors of the pathogen? from my understanding, the yellow thing (macrophage) takes on the pathogens **antigens** (in order to signal to the other lymphocytes about a 'non-self')... is that right?.. LA

Is a macrophage a type of phagocyte? BN

Hi Lia. My understanding, (although i may be wrong, so best to check with the Voj) is that the pathogens have specific receptors (antigens). Complement antibody molecules react with them to stimulate the production of more antibodies in order to fight or reject the 'non-self'. Thus they trigger the cell to be engulfed, and serve as a form of //identity// for the foreign material, but are not the actual invador.

Hi Bass, just a quick thing i noticed with your response, yes majority of it is correct i just want to say one thing. It isn't complementary antibody molecules that attach to the antigen, it is the receptors on the b-cells that are the complement to antigen, this complex created between the b-cell and antigen then stimulates the production of antibodies, then these antibodies attach to the antigens and highlight the antigen so a suitable cell, either cytotoxic t-cell or a macrophage will come and destroy the invader. MW

Also Bec, i think a phagocyte is a type of macrophage.. i'm pretty sure a macrophage only refers to a large white blood cell that happens to carry out phagocytosis. LB

It appeared in the clip that the macrophage underwent self destruction. Was this a programed response to take place once it had engulfed the foreign substance?

From what I now understand is that once the macrophage ingested the invading pathogen it did not actually self destruct but was destroyed by cytotoxic t-cells, which can then cause it to lyse or self destruct by apoptysing. MW

Is it the B cells or T cells that detected the non self antigen? I thought B cells have the glycoproteins on their membrane that attach to the antigen and recognise it - then once there is a match, the B cells or rather plasma cells start producing that type of antibody.

media type="file" key="specific immune response.wmv"
 * Animation **