Gun Frisk

Indications that maternal Coxsackie B virus infection during pregnancy is a risk factor for childhood-onset IDDM

SummaryIn a population-based setting, we traced serum samples collected at time of birth from 55 mothers whose children later developed insulin-dependent diabetes (IDDM) and matched them pairwise to control subjects who gave birth at the same hospital during the same month. The sera were analysed for IgM antibodies to coxsackie B virus serotypes 2, 3 and 4 (CBV-2, 3 and 4) using a type-specific Μ-antibody-capture radioimmunoassay. Despite a decreased power due to the close matching by time of birth we found a significantly higher frequency of CBV-3 IgM at delivery in mothers whose children later became diabetic compared to their matched control subjects. When using the presence of CBV-3 IgM as a risk factor the Mantel-Haenszel odds ratio estimate (95% confidence limits) was 2.57 (1.02; 7.31), p=0.043. For CBV-2 and CBV-4, respectively no significant difference was found between mothers of patients and control subjects. According to the odds ratio estimate for CBV-3 and the proportion of exposed mothers among patients estimated in this study the aetiological fraction for this risk determinant would be 27%. In conclusion, this study indicates that children of mothers who expressed CBV IgM at delivery are at increased risk for developing childhood onset IDDM. A fetal infection with CBV similar to rubella virus may initiate autoimmunity or cause persistent infection that may lead to progressive beta-cell destruction.

The diagnosis of insulitis in human type 1 diabetes

To the Editor: During a workshop concerning the histopathological characteristics of insulitis in human type 1 diabetes (fifth annual meeting of the JDRF Network for Pancreatic Organ Donors with Diabetes [nPOD], 10 February 2013, Jacksonville, FL, USA), a consensus opinion was reached on the criteria necessary for the diagnosis of insulitis, and a definition of insulitis was agreed, as detailed in the text box. Workshop attendees included many leading researchers in the

Detection of a low-grade enteroviral infection in the islets of Langerhans of living patients newly diagnosed with type 1 diabetes

The Diabetes Virus Detection study (DiViD) is the first to examine fresh pancreatic tissue at the diagnosis of type 1 diabetes for the presence of viruses. Minimal pancreatic tail resection was performed 3–9 weeks after onset of type 1 diabetes in six adult patients (age 24–35 years). The presence of enteroviral capsid protein 1 (VP1) and the expression of class I HLA were investigated by immunohistochemistry. Enterovirus RNA was analyzed from isolated pancreatic islets and from fresh-frozen whole pancreatic tissue using PCR and sequencing. Nondiabetic organ donors served as controls. VP1 was detected in the islets of all type 1 diabetic patients (two of nine controls). Hyperexpression of class I HLA molecules was found in the islets of all patients (one of nine controls). Enterovirus-specific RNA sequences were detected in four of six patients (zero of six controls). The results were confirmed in various laboratories. Only 1.7% of the islets contained VP1+ cells, and the amount of enterovirus RNA was low. The results provide evidence for the presence of enterovirus in pancreatic islets of type 1 diabetic patients, which is consistent with the possibility that a low-grade enteroviral infection in the pancreatic islets contributes to disease progression in humans.

Pancreatic biopsy by minimal tail resection in live adult patients at the onset of type 1 diabetes: experiences from the DiViD study

Pancreatic biopsy by minimal tail resection in live adult patients at the onset of type 1 diabetes : experiences from the DiViD study

Coxsackie B virus IgM in children at onset of type 1 (insulin-dependent) diabetes mellitus: evidence for IgM induction by a recent or current infection.

SummaryThirty-five children with newly-diagnosed Type 1 (insulin-dependent) diabetes mellitus and their 47 siblings were investigated for the presence of IgM antibodies to Coxsackie B virus serotypes 1–5 (CBV1-5) with the aid of μ-antibody-capture radioimmunoassays. When a high cut-off value was used, 16 (46%) diabetic children and 16 (34%) siblings showed CBV-IgM. Of the siblings of diabetic patients positive for CBV-IgM, 11 (44%) were CBV-IgM-positive; the corresponding figure for the siblings of negative patients was five (26%). With a lower cut-off value, leading to a “borderline titre”, the frequency of IgM positivity increased in both the patients and siblings. When the borderline titres were included, the number of IgM-positive patients was 19 (54%) and the corresponding number of siblings was 29 (62%). Of the siblings of positive patients, 27 (93 %) showed CBV-IgM, and of the siblings of the negative patients, two (11 %) were CBV-IgM-positive. Sixteen (89 %) siblings of IgM-negative patients remained negative. Regarding the serotypes of CB V to which IgM was directed, CBV 4 was most frequent, followed by serotypes CBV 3, CBV 2, CBV 5 and CBV 1. There was a striking similarity between the individual diabetic child and his or her sibling(s) concerning this specificity of IgM. It is concluded that within most families with a newly-diagnosed diabetic child positive for CBV-IgM the same serotype(s) of the virus circulates and that the intrafamilial spread of virus is considerable. The results strongly indicate that the IgM detected was CBV-specific and caused by a recent or current CBV infection. It is highly probable that the same strain of virus was present in different members of the same family. Therefore, if diabetogenic CBV strains do in fact exist, additional factors must be of importance for the development of Type 1 diabetes in children infected with such a CBV strain but remaining non-diabetic.

The possible role of Coxsackie A and echo viruses in the pathogenesis of type I diabetes mellitus studied by IgM analysis

IgM antibodies to Coxsackie B virus (CBV) have recently been observed in the serum of a relatively high proportion of children with newly diagnosed insulin-dependent diabetes mellitus (IDDM). In the present study, 108 IDDM patients below the age of 15 years, diagnosed during the period 1976 to 1985, were investigated at the onset of their disease by mu-antibody-capture radioimmunoassay (RIA) of IgM against seven different enterovirus antigens, namely virions of CBV serotypes 1-5 (CBV 1-5) and procapsids of CBV 3 and CBV 5. As has been shown the RIAs with virions give type-specific or narrow type-specific reactions, whereas procapsids react with IgM against both homotypic and heterotypic enteroviruses. The annual frequency of IgM against virions varied between 15 and 76% (mean 38%). IgM against CBV3 and CBV2 predominated, but IgM against the other serotypes was also observed. When procapsids were used as antigen, the frequency of IgM varied between 11 and 86% (mean 63%). With virions and procapsids, the corresponding variation was 44-100% (mean 70%). The total number of patients exhibiting virion-IgM was 41, whereas procapsid-IgM alone [indicating an infection with Coxsackie A virus (CAV) and/or echo virus (EV)] was detected in 36 patients. For 2 of the years, samples of serum from control groups were included. These showed a significantly lower frequency of IgM in both the virion and the procapsid RIAs. It is concluded that not only infection with CBV but also that with other enteroviruses, such as CAV and/or EV, may be involved in the pathogenesis of IDDM in children.

Tissue Culture of Isolated Human Pancreatic Islets Infected With Different Strains of Coxsackievirus B4: Assessment of Virus Replication and Effects on Islet Morphology and Insulin Release

The aim was to study whether different strains of Coxsackievirus B4 (CBV-4) are able to infect human pancreatic islet cells in vitro and cause morphological and functional damages. Isolated islets maintained in tissue culture were infected with five well- characterised strains of CBV-4. Aliquots of the culture medium were analysed with regard to virus replication and insulin content. Infected and uninfected islets were examined by light microscopy to determine the degree of virus-induced cytopathic effect (CPE). The results showed that the islet cells were susceptible to infection by all the strains of CBV-4 although the outcome of the infection differed. The virus titres obtained at 48 and 72 hours post infection differed significantly between all the CBV-4 strains (p < 0.001), indicating different ability to replicate in islet cells. Pronounced to weak CPE, which was partly due to the origin (donor) of the islets, was induced by four of the five CBV-4 strains. One strain (VD2921) replicated without causing CPE despite high virus titres. One (V89-4557) of the CBV-4 strains always revealed pronounced CPE. Infection by this strain also caused functional impairment that significantly affected insulin response to high glucose at 48 hours post infection (p < 0.001). Replication of another CBV-4 strain (JVB) in the islet cells significantly increased the release of insulin compared to non-infected control cells (p < 0.001) indicating damage of the β-cells leading to leakage of insulin.

The Swedish childhood diabetes study III: IgM against coxsackie B viruses in newly diagnosed Type 1 (insulin-dependent) diabetic children — no evidence of increased antibody frequency

SummarySera from essentially all Swedish children aged 0–14 years with Type 1 (insulin-dependent) diabetes mellitus with onset during an autumn period (October–December 1985) and a late spring period (May–June 1986) were selected. In all, 98 patients were analysed for IgM antibodies against coxsackie B virus serotypes 1 through 5 by a μ-antibody capture radio immunoassay technique. Sera from 94 referent children matched for age, sex and residential area, collected during the same period, were also analysed. During the autumn period, 10 out of 67 (15%) diabetic children were IgM positive while 14 out of 75 (19%) of the healthy referent children demonstrated positivity. During the late spring period only one out of 31 (3%) children with diabetes and two out of 19 (10%) referent children were IgM positive. In the diabetic patients, five were coxsackie B2 positive while coxsackie B1, 3, 4 and 5 were represented by one to three patients each. Eight referent children were coxsackie B4 positive, six were B3 positive and two B2 positive, while no referent children were positive against coxsackie B1 and 5. During these two periods in late 1985 and early 1986 these data demonstrate no evidence of increased antibody frequency against coxsackie B virus 1 through 5 at the onset of childhood diabetes in Sweden.

A unifying hypothesis on the development of type 1 diabetes and celiac disease: Gluten consumption may be a shared causative factor

This paper presents a hypothesis of the aetiology of the increasing incidence of type 1 diabetes (T1D). This together with the global increased incidence of celiac disease (CD) and that these increases cannot be explained by genetic factors suggest a common environmental factor for these two diseases. Even though enterovirus (EV) infections are believed to trigger T1D and gluten is the trigger of CD, the increasing intake of gluten containing products all over the world could be the trigger for both diseases directly and indirectly. It has been shown that the duration of exposure to gluten is related to the prevalence of T1D. It has also been shown that T1D patients at onset have an inflammatory reaction in the gut. Hence, early diagnose of CD followed by elimination of dietary gluten will lead to a decreased incidence of T1D.

Induction of the chemokine interferon-γ-inducible protein-10 in human pancreatic islets during enterovirus infection

Aims/hypothesisEnterovirus infections have long been suspected to be environmental factors that may cause type 1 diabetes, but the pathways leading from infection to beta cell destruction are still unknown. We therefore examined whether enterovirus infection of human islets leads to upregulation of interferon-γ-inducible protein (IP-10, now known as chemokine [C–X–C motif] ligand 10 [CXCL10]), a chemokine important for the induction of insulitis.MethodsIsolated human islets were infected with three different strains of Coxsackie B4 virus. IP-10 expression and secretion from the infected human islets were then measured using RT-PCR and ELISA at several time points.ResultsIP-10 was clearly upregulated in and secreted from human islets during enterovirus infection. This was demonstrated with three different strains of Coxsackie B4 virus, two of which are lytic to islets and one which is non-lytic and can establish a persistent infection in human islets.Conclusions/interpretationWe propose that enterovirus-induced upregulation of IP-10 during infection of the islets in vivo is the first step towards destructive insulitis. Our findings support the idea that enterovirus infection triggers immune-mediated beta cell destruction, and for the first time suggest a possible mechanism behind enterovirus-induced diabetes.