Monoclonal Antibodies

• Antibody


  A protein made and released by lymphocytes. Each one is specific to one molecule (or antigen) which it can bind to. Part of the immune response to pathogens.
• Antigen


  This a protein found on the surface of cells. It allows the body to identify its own cells or any cells from other sources, like pathogens.
• Clone


  A genetically identical cell or organism.
• Detection

  Use of monoclonal antibodies. Antibodies can identify the presence of molecules like hormones or other chemicals in the blood.
• Hybridoma cell

  A cell formed by fusing a tumour cell with a lymphocyte that produces a specific antibody. These are used to produce lots of monoclonal antibodies.
• Lymphocyte


  A type of white blood cell that makes and releases antibodies.
• Monoclonal antibody

  An antibody made by a group of genetically identical (cloned) cells. These will make lots of identical antibodies which will all bind the same antigen.
• Protein


  A molecule made from amino acids.
• Side effects


  These are unwanted effects of a treatment. Those for monoclonal antibody treatment include fever, nausea, headaches and rashes.
• Tumour cell


  A cell taken from a cancerous tumour. These cells divide uncontrollably by mitosis.
• Chromosome 


  A structure made up of large molecules of DNA. They carry genes which control the characteristics of the body. There are 46 of these in a normal human body cell, found in 23 pairs
• Gene 


  A small section of DNA on a chromosome. Each codes for a particular sequence of amino acids to make a specific protein (eg colour of iris)
• DNA 


  A molecule made of very long strands twisted to form a double helix, which contain 4 different compounds called bases.

  
• Mitosis


  When a cell divides into two to make two identical cells. This type of cell division is needed for growth, replacing worn out cells and repairing damage.

  
• Stem Cells 


  An undifferentiated cell of an organism from which certain other cells can arise from differentiation, or is capable of giving rise to more stem cells. These can be obtained from embryos, adults and meristems in plants.
• Undifferentiated 


  When a cell has not been differentiated into a specific type of cell. Stem cells are described as this.
• Embryonic stem cells

  Differentiate to form all the specialised cells in your body. These can be cloned and made to differentiate into most different types of human cells.
• Where are chromosomes found?

  The nucleus of the cell
• Therapeutic Cloning 


  Where an embryo is produced with the same genes as a patient and then used to get stem cells which can be used for medical treatment as they are not rejected by the patient's body
• Functions of mitosis


  1. Growth and development of an organism

  2. Repair of tissues by replacing cells
• What are the 3 stages of the cell cycle? 


  Interphase, mitosis and cytokinesis
• Cytokinesis


  When the cell cytoplasm divides to form the daughter cells
• Interphase 


  Longest part of cell cycle, cell grows and develops and function parts in our body. Almost at the end of interphase, DNA and chromosomes double.
• What are 3 sources of embryonic stem cells?

  1. aborted embryos
  2. Spare embryos from IVF
  3. umbilical cord/placental donation
• Where can we find adult stem cells and what is a disadvantage of this?

  Bone marrow and some other tissues BUT these only develop into a limited range of cells (eg those found in bone marrow develop into blood cells)
• Meristem tissue 


  This can differentiate into any type of plant cell throughout the life of the plant.
• What are 2 uses of stem cells from meristems?

  1. Rare species can be clones to protect from extinction as clones can be produced quickly and economically

  2. Crop plants with special features such as disease resistance can be cloned to produce large numbers of identical plants for farmers
• What conditions might stem cells be able to treat?

  1. Diabetes - grow new pancreatic tissue
  2. Paralysis - grow/replace damaged neurones
• What are downsides to use of stem cells?

  1. Potential risks such as transfer of viral infection

  2. Ethical or religious objections
• Monoclonal antibodies 


  Antibodies produced from a single clone of cells. They are specific to one binding site on one antigen and so target a specific chemical or cell in the body.
• How can monoclonal antibodies be used to treat diseases such as cancer?

  - monoclonal antibody can be bound to a radioactive substance, toxic drug or chemical

  - this stops cells growing and dividing

  -delivers substance to cancer cells without harming other healthy cells
• Disadvantages of monoclonal antibodies

  1. Create more side effects than expected

  2. Producing the right monoclonal antibodies and attaching them to other compounds is more difficult than expected