deposit larvae instead of eggs

-       fly retain larvae in development until they reach stage of maturity and are released into the soil

-       better chance of surviving and reaching maturity

flagella arises near nucleus, dividing form, still lacks surface coat

- undulating membrane shortened, kinetoplast anterior to nucleus

organisms all exhibiting single antigenic type

display different antigenic makeup than dominant population

gene that is currently being expressed on the outer surface of the trypanosome

-       basic copy genes that are being expressed so that they can be copied

activated genes that do not need to be copied because they are already close to telomere/expression loading site

- show up the most because they are close to telomere and don’t need to be replicated

genetically acquired immunity

            - genes dictate whether you are susceptible to disease or not

develop immunity from response of when you acquired       sickness/disease

 Humoral responses  

immunity mediated by secreted antibodies (antibody production)

-       B cells transform into plasma cells which secrete antibodies

-       CD4+ on T-helper cells provides co-stimulation, stimulated T-helper cells

-       Antibodies bind to antigens on surfaces of invading parasite, which flags it for destruction

-       Th2 activation and cytokine production Look up (graphic on powerpoint)

immunity function associated with cells, does not involve antibodies

-       activation of phagocytes, natural killer cells, antigen-specific cytotoxic T-lymphocytes, and release of various cytokines in response to an antigen

1.     activate antigen specific cytotoxic T-lymphocytes that induce apoptosis of cells expressing parasites antigen type

2.     activate macrophages to kill

3.     stimulate cells to secrete variety of cytokines to influence function of cells involved in adaptive immune response and innate immune response

T-independent antigens – operate independent of T-cells

-       able to trigger B cells to produce antibodies, without the presence of T cells

-       able to skip T cells and directly trigger B cells to produce antibodies

IgM antibody 

immunoglobulin M, antibody produced by B cells

-       largest antibody in human circulatory system, spleen is major site of specific IgM production

-       first antibody to appear in response to initial exposure to antigen