they need to have their tissues identified as "not them". The majority of these little filament thingies distributed about the cell wall are built of saccharides and proteins. There had better be enough saccharides to go around to make sure that these glycoforms are built correctly, anything less can result in bodily dysfunction... cancer, rheumatoid conditions, autoimmunity, arteriosclerosis, etc may be the result of a lack of these specific saccharides.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=151709381: J Rheumatol. 2004 Jun;31(6):1211-7. Related Articles, Links
Antiagalactosyl IgG antibodies in juvenile idiopathic arthritis, juvenile onset Sjogren's syndrome, and healthy children.
Maeno N, Takei S, Fujikawa S, Yamada Y, Imanaka H, Hokonohara M, Kawano Y, Oda H.
Department of Bacteriology and the Department of Pediatrics, Faculty of Medicine, Kagoshima University, Kagoshima, Japan.
This can happen because specific sugars are lacking in their joint tissues....
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=125165721: Eur J Immunol. 2002 Dec;32(12):3776-84. Related Articles, Links
Glycosylation of type II collagen is of major importance for T cell tolerance and pathology in collagen-induced arthritis.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=129278591: Bioorg Med Chem. 2003 Sep 1;11(18):3981-7. Related Articles, Links
Role of the galactosyl moiety of collagen glycopeptides for T-cell stimulation in a model for rheumatoid arthritis.
Holm B, Baquer SM, Holm L, Holmdahl R, Kihlberg J.
Organic Chemistry, Department of Chemistry, Umea University, SE-901 87
Umea, Sweden.