BIOL 135 Flashcards
How to T-helper cells activate the accuired immune response?
When helper cell activated it in turn activates Cytotoxic T cells and B cells which kill infected cells and produce antibodies
How does HIV virion enter T cells?
GP120 binds to CD4
GP41 binds to CXCR4
Viral membrane fuses with T cell membrane
Capsid enters
How is HIV infection detected?
Antibodies to HIV
Viral RNA
Fall in T helper cell number
What is an ELISA and what are the steps?
Enzyme-Linked-ImmunSorbent Assay
1) Antigen bound to well
2) Pateint serum added
3) Anti-human antibody binds to target antibody (enzyme linked)
4)substrated added and converted into coloured product by the enzyme
Absorbances measures in spectrophotometer
What is latex particle agglutination?
Latex particles covered in HIV antigen clump when anti-HIV containing blood added
What methods can be used to detect HIV RNA beforr anibodies are detectable?
RT-PCR (using reverse transcriptase due to HIV being retrovirus)
Monitoring of infection via T helper cell numbers using Flow cytometry and flurescence activated cell sorting (FACS)
How does flow cytometry/FACS work?
Antibodies with a flourescent label attatched are mixed with target cells and passed through a flow cell with a laser pointed at it.
Fluorescent cells release light in response to the laser and photomultiplier tubes detect this.
This can be used to count number of cells and multiple labels can be used to count more than one type at a time.
What is multiple myeloma?
It is a cancer of immunoglobulin producing plasma cells in the bone marrow. Result in a large ammount of immunoglobulin produced which can be detected via cellulose acetate electrophoresis.
The malignant plasma cells in the bone marrow activate osteoclasts which break down the bone.
What is pernicious anaemia?
Autoimmune disorder against the gastric parietal cells which take up B12
B12 is used in RBC so less RBCs made and less 02 transported therefore fatigue
What are the main structures in the stomach?
Fundus, cardia and the body
Without being filled it has Rugae (folds) allowing for it to expand.
What are the strucural layers of the stomach wall?
Mucosa (surface mucus layer with gastric pits in it)
Sub mucosa
Muscularis
Serosa
What cell types are in the gastric pit?
Surface mucus cells
Mucous necks
Parietal cell (H+, Cl- and intrinsic factors
Chief cell (secretes pepsinogen and gastric ipase)
G cell (secretes gastrin into blood)
How is HCl produced by parietal cells?
Carbonic anhydrase syntehsisses it using water and carbon dioxide into H+ and HCO3-
What is the strucute of a villus?
Is has a mucosa layer comprised of asorptive cells, goblet cells, endorendocrine cells and paneth cells.
How is H. pylori able to survive in the gut and how it forms ulcers?
An ulcer is a break in the gut lining that fails to heal. H. pylori disrupts the mucus layer in the stomach and pepsin and HCl causes the damage to unprotected tissues. Antibiotics and proton-pump inhibitors can be used to reduce HCl formtaion.
H. pylori can produce urease enzyme which converts urea into ammonia + carobn dixoidoe which neutralises the acidic conditions.
