Immune system proteinase inhibitors

An example of a so-called primitive immune system, somewhat parallel to that in animals, is provided by the finding by Nelson et al. (29) that two proteinase inhibitors accumulate in leaves of tomato plants when attacked by chewing insects or mechanically wounded. The accumulation of the two antinutrient proteins is apparently a defense response and is initiated by the release of a putative wound hormone called the proteinase inhibitor inducing... 

Some parasites can acquire proteinase inhibitors from their host (78,87) which may provide protection from exogenous or endogenous proteinases but could also be important in masking antigenic extracellular parasite proteinases from the host immune system. 

Molla A, Akaike T, Maeda H. Inactivation of various proteinase inhibitors and the complement system in human plasma by the 56-kilodalton proteinase from Serratia marcescens. Infect Immun 1989 57 1868-1871. 

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