Seroreactivity against Specific L5P Antigen from Mycobacterium avium subsp. paratuberculosis in Children at Risk for T1D

Abstract

Aims/HypothesisAlthough numerous environmental agents have been investigated over the years as possible triggers of type 1 diabetes (T1D), its causes remain unclear. We have already demonstrated an increased prevalence of antibodies against peptides derived from Mycobacterium avuim subsp. paratuberculosis (MAP) homologous to human zinc transporter 8 protein (ZnT8) and proinsulin in Italian subjects at risk for or affected by T1D. In this study, we compared titers of the previously detected antibodies with seroreactivity to MAP lipopentapetide (L5P) that recently emerged as a strong immunogenic component able to specifically distinguish MAP from other mycobacteria.MethodsPlasma of 32 children and youth at risk for T1D including follow-up samples and 42 age-matched healthy controls (HC) recruited at the Tor Vergata University Hospital in Rome was analyzed by indirect ELISA for the presence of antibodies against MAP-derived epitopes MAP3865c133–141, MAP3865c125-133, MAP2404c70-85 and MAP1,4αgbp157-173 along with their ZnT8 and proinsulin homologs. The data were analyzed through two-tailed Mann-Whitney U test and relation between variables was determined by principal component analysis.ResultsResponses to L5P were not detectable in subjects whose initial seroreactivity to MAP peptides and their human homologs was lost in follow-up samples, whereas anti-L5P antibodies appeared constantly in individuals with a stable immunity against MAP antigens. The overall coincidence in positivity to L5P and the four MAP epitopes both in children at risk for T1D and HC exceeded 90%.ConclusionsMAP-derived homologs may cross-react with ZnT8 and proinsulin peptides inducing immune responses at a young age in subjects predisposed for T1D. Thus, L5P may have a diagnostic value to immediately indicate the presence of anti-MAP seroreactivity when evaluation of a more complex antibody status is not required. Almost complete coincidence in responses to both types of antigens lends support to the involvement of MAP in T1D.

Presence of Infection by Mycobacterium avium subsp. paratuberculosis in the Blood of Patients with Crohn’s Disease and Control Subjects Shown by Multiple Laboratory Culture and Antibody Methods

“…Mycobacterium avium subspecies paratuberculosis (MAP) is accepted as the cause of Johne’s Disease (JD) [ 1 ], a chronic diarrheal wasting disease of cattle and a wasting disease in sheep and goats [ 2 ] and has long been suspected to be involved in the etiology of Crohn’s Disease (CD), an inflammatory bowel disease (IBD) of humans [ 3 ]. MAP and/or CD are also associated with many other autoimmune diseases including multiple sclerosis (MS) [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ], type I diabetes mellitus (T1DM) [ 14 , 15 , 16 , 17 , 18 , 19 ], rheumatoid arthritis [ 20 , 21 , 22 ], Sjogren’s syndrome [ 23 ], asymmetric lateral sclerosis [ 24 ], celiac disease [ 25 ], depression [ 26 ], thyroiditis [ 27 ], and the neurodegenerative diseases including Alzheimer’s disease [ 28 ] and Parkinson’s disease [ 29 ]. A diarrheal/wasting illness associated with infection with MAP has also been reported in non-human primates [ 30 ].…”

Presence Of Infection By Mycobacterium Avium Subsp. Paratuberculosis In The Blood Of Patients With Crohn’s Disease And Control Subjects Shown By Multiple Laboratory Culture And Antibody Methods

“…Mycobacterium avium subspecies paratuberculosis (MAP) is accepted as the cause of Johne's Disease (JD) [1], a chronic diarrheal wasting disease of cattle and a wasting disease in sheep and goats [2] and has long been suspected to be involved in the etiology of Crohn's Disease (CD), an inflammatory bowel disease (IBD) of humans [3]. MAP and/or CD are also associated with many other autoimmune diseases including multiple sclerosis [4][5][6][7][8][9][10][11][12][13], type I diabetes mellitus [14][15][16][17][18][19], rheumatoid arthritis [20][21][22], Sjogren's syndrome [23], asymmetric lateral sclerosis [24], systemic sclerosis, celiac disease [25], depression [26], thyroiditis [27], and the neurodegenerative diseases including Alzheimer's disease [28] and Parkinson's disease [29]. A diarrheal/wasting illness associated with infection with MAP has also been reported in non-human primates [30].…”

Altered humoral immunity to mycobacterial antigens in Japanese patients affected by inflammatory demyelinating diseases of the central nervous system

“…MAP lipopentapetide (L5P) is a specific cell wall component of MAP capable to induce a strong host humoral response, and able to distinguish MAP from other mycobacteria including BCG 23 . A highly specific IgG responses to L5P were detected in patients affected by Crohn’s disease and in children at risk for type 1 diabetes 24 , 25 .…”