Changes

*Anaphylactic shock caused by [[IgE]] production, e.g. after the rupture of hydatid cysts

*Anaphylactic shock caused by [[IgE]] production, e.g. after the rupture of hydatid cysts

*Cross-reaction of antibodies with host tissue, e.g. ''O. volvulus'', the cause of river blindness, expresses an antigen similar to a protein in the retina

*Cross-reaction of antibodies with host tissue, e.g. ''O. volvulus'', the cause of river blindness, expresses an antigen similar to a protein in the retina

*Excessive production of cytokines, such as TNF-alpha, may contribute to pathology of diseases such as malaria

*Excessive production of cytokines, such as TNFα, may contribute to pathology of diseases such as malaria

=='''Evading immune defences'''==

=='''Evading immune defences'''==

Parasites can evade an immune response from the host by changing the antigens presented to the host, produce antigens that mimic the host's antigens and can produce down-regulating factors which suppress or modify the host's immune responses. Having a rapid turnover of their surface coat when host cells bind and by being able to live in sites which are protected from the host's immune response allow parasites to establish themselves in a particular species.

Parasites can evade an immune response from the host by changing the antigens presented to the host, produce antigens that mimic the host's antigens and can produce down-regulating factors which suppress or modify the host's immune responses. Having a rapid turnover of their surface coat when host cells bind and by being able to live in sites which are protected from the host's immune response allow parasites to establish themselves in a particular species.

*Selection of innapropriate defences- by exploiting the 'adjuvant' mechanism, some parasites are able to activate the inappropriate helper T cell subset, e.g Leishmania

*Selection of innapropriate defences - by exploiting the 'adjuvant' mechanism, some parasites are able to activate the inappropriate helper T cell subset, e.g Leishmania

*Antigenic variation avoids recognition by antibody and complement, e.g. ''T. brucei''

*Antigenic variation avoids recognition by antibody and complement, e.g. ''T. brucei''

*Inhibiting fusion of lysosomes

*Inhibiting fusion of lysosomes

*Escaping into the cytoplasm, e.g. ''T. cruzi''

*Escaping into the cytoplasm, e.g. ''T. cruzi''

*Inhibiting respiratory burst, e.g. Leishmania

*Inhibiting respiratory burst, e.g. Leishmania

*Forming cysts in muscle tissue, e.g. ''T. spiralis''- also develops decay accelerating factor (DAF)

*Forming cysts in muscle tissue, e.g. ''T. spiralis'' - also develops decay accelerating factor (DAF)

*Production of antioxidants, e.g. ''W. bancrofti''

*Production of antioxidants, e.g. ''W. bancrofti''