FACTORS INFLUENCING IMMUNOGENICITY CHEMICAL NATURE OF IMMUNOGENS

A. Proteins -The vast majority of immunogens are proteins. These may be pure proteins or they may be glycoproteins or lipoproteins. In general, proteins are usually very good immunogens.
B. Polysaccharides - Pure polysaccharides and lipopolysaccharides are good immunogens.
C. Nucleic Acids - Nucleic acids are usually poorly immunogenic. However, they may become immunogenic when single stranded or when complexed with proteins.
D. Lipids - Lipids are non-immunogenic, although they may be haptens.

question
add these differences to the table you created in the previous post.
Write up the answers/table clearly, with your name and reg no, and bring to class when lectures begin, for assessment.

FACTORS INFLUENCING IMMUNOGENICITY Contribution of the Immunogen

1. Foreignness - The immune system normally discriminates between self and non-self such that only foreign molecules are immunogenic.
2. Size - There is not absolute size above which a substance will be immunogenic. However, the larger the molecule the more immunogenic it is likely to be.
3. Chemical Composition - The more complex the substance is chemically the more immunogenic it will be. The antigenic determinants are created by the primary sequence of residues in the polymer and/or by the secondary, tertiary or quaternary structure of the molecule.
4. Physical form - Particulate antigens are more immunogenic than soluble ones and denatured antigens more immunogenic than the native form.
5. Degradability - Antigens that are easily phagocytosed are generally more immunogenic. This is because for most antigens (T-dependant antigens) the development of an immune response requires that the antigen be phagocytosed, processed and presented to helper T cells by an antigen.

question
tabulate the differences between immunogenic and non immunogenic for each of the factors described above

cell markers

So how do you recognize another DUT student, even if you dont know him/her? Well these days, its easy cos they are probably looking bored, waiting for lectures to start.
Okay so how do you recognize academic staff of the Biomed dept? I suppose because we look like we belong here, and may have a look of authority about us? I'm not actually sure.
The point i am trying to make is that we use non verbal clues to identify other people.
So how do you suppose cells in the body recognise each other? Do you think they carry signs that say: Hello. I am a Tc cell. Who are you? I think noT!!!!!!!!!!!!!

All cells express (important word used here, remember it) cell markers. A cell marker is a structure found on the surface of a cell. It is not part of the cell membrane, so it cannot be drawn as part of the cell membrane. It is like an address for cells. Different cell markers are found on different cells. Cells 'talk' to each other via cell markers.
Now these cell markers do not actually connect with each other, rather they interact with each other, meaning there is a distinct clear space between each cell marker.
now to the drawing: a spherical shape represents cells. Any shape will represent a cell marker, BUT remember the lock and key mechanism thingy!!!
so i want you to draw me 2 cells interacting with each other via cell markers which 'fit' into each other. NB! no contact between the cell markers. Cell markers are structures on the surface of the cells
now label them as follows:
Tc cell expressing CD8
Th cell expressing CD4

so if we had to write down in words what you just drew:
a Tc cell expressing CD8 interacts with CD4 expressed by Th cell.

makes sense??? if it doesnt, let me know please . Enough for today. Rest now

lock and key mechanism

This may sound familiar to you, I hope. I think you may have done something similar in enzymes in life sciences.
Do you remember how to draw these? I just need you to be able to show me that one shape 'fits' into or is aligned with the other shape.
Try to draw various lock and key mechanism so that you are familiar with the concept. We are going to need it in the next section.

immune cells

The cells involved in the immune response are called immune cells lol. They can be classified into granulocytes and agranulocytes. Granulocytes are so called because they have ___________ and agaranulocytes have no ________.
Examples of granulocytes are neutrophils, basophils, eosinophils. Examples of agranulocytes are lymphocytes, which can be further classified into T cells and B cells.
question: draw simple unlabelled diagrams to show the differences between each type of cell named above
What cell is often called a PMN? And what does PMN stand for?

T cells are involved in cell mediated immunity (CMI) whilst B cells are involved in humoral immunity (HI). Humoral immunity makes use of Ab to eliminate Ag whilst CMI uses cells to kill Ag. There are different types of T cells, Tc Ts Th and NK cells. Tc is a cytotoxic T cell, Ts is a suppressor T cell, Th is a helper T cell and NK is a natural killer cell. A Tc cell kills, a Ts suppresses or stops the IR, a Th is required to start the IR and the NK cell does what it says, it just kills. All it needs is something to kill.
B cells do not produce Ab. B cells differentiate into plasma cells which produce Ab

benefits of normal flora

Normal flora benefits us.Organisms in the gut produce vitamin K, and help digest carbohydrates. Normal flora on the body surface prevent opportunistic infections. When both man and microbe benefit, the relationship is called mutualism. In commensalism, one party benefits and the other does not. Parasitism refers to harm being done to man by microbes.

It must be noted that if normal flora moves out of their normal area of residence, they can cause severe infections. As an example, E coli is supposed to be in the gut area only; if it gets introduced into the urinary tract it can cause a urinary tract infection (UTI).

antimicrobial questions

Do a very quick screen of the shelf in you local supermarket and see how many soaps and
dishwashing liquids claim to be antimicrobial. Also read the packaging and see if it describes what ingredients make it antimicrobial.
Do a screen of friends and family to see who uses an antimicrobial product over a regular product. Ask them why and record the answers.