Jacques Weill

Increased Level of Interferon-α in Blood of Patients with Insulin-Dependent Diabetes Mellitus: Relationship with Coxsackievirus B Infection

The activation of the interferon (IFN)-alpha system and its relationship with coxsackievirus B (CVB) infection has been analyzed in 56 patients with insulin-dependent diabetes mellitus (IDDM; 25 children and 31 adults). Elevated levels of IFN-alpha were found in plasma of 70% of patients (39/56), and a positive detection of IFN-alpha mRNA in blood cells by reverse transcriptase-polymerase chain reaction (RT-PCR) was observed in 75% of patients (42/56). Enterovirus (EV) RNA assayed by seminested RT-PCR was detected in the blood of 50% of IFN-alpha-positive patients but not in any IFN-alpha-negative patients. The results of genotype analysis of amplified EV RNA sequences (5 CVB2, 8 CVB3, and 8 CVB4) were concordant with the results of CVB-neutralization tests. The comparison between IFN-alpha, EV RNA, and serology suggested that the proportion of CVB infection associated with IFN-alpha positivity might be higher than is predicted from the investigation of EV RNA. Together, the results suggest that, in a majority of cases, a CVB infection is associated with clinical IDDM.

Viral protein VP4 is a target of human antibodies enhancing coxsackievirus B4- and B3-induced synthesis of alpha interferon.

ABSTRACT Coxsackievirus B4 (CVB4)-induced production of alpha interferon (IFN-α) by peripheral blood mononuclear cells (PBMC) is enhanced in vitro by nonneutralizing anti-CVB4 antibodies from healthy subjects and, to a higher extent, from patients with insulin-dependent diabetes mellitus. In this study, we focused on identification of the viral target of these antibodies in CVB systems. High levels of IFN-α were obtained in supernatants of PBMC incubated with CVB4E2 or CVB3 and plasma from healthy subjects and, to a higher extent, from patients. The VP4 capsid proteins dissociated by heating at 56°C from CVB4E2 (VP4CVB4) and CVB3 (VP4CVB3) but not H antigen preincubated with plasma from healthy subjects or patients inhibited the plasma-dependent enhancement of CVB4E2- and CVB3-induced IFN-α synthesis. There was no cross-reaction between VP4CVB4 and VP4CVB3 in the inhibiting effect. IFN-α levels in culture supernatants showed dose-dependent correlation with anti-VP4 antibodies eluted from plasma specimens using VP4-coated plates. There were higher index values for anti-VP4 antibodies detected by enzyme-linked immunosorbent assay (ELISA) and higher proportions of positive detection in 40 patients than in 40 healthy subjects (80% versus 15% for anti-VP4CVB4). There was no relationship between the levels of anti-CVB neutralizing antibodies and the detection of anti-VP4 antibodies by ELISA. The CVB plasma-induced IFN-α levels obtained in PBMC cultures in the anti-VP4 antibody-positive groups were significantly higher than those obtained in the anti-VP4 antibody-negative groups regardless of the titers of anti-CVB neutralizing antibodies. These results show that VP4 is the target of antibodies involved in the plasma-dependent enhancement of CVB4E2- and CVB3-induced IFN-α synthesis by PBMC.

Circulating and cell-bound antibodies increase coxsackievirus B4-induced production of IFN-alpha by peripheral blood mononuclear cells from patients with type 1 diabetes.

Increased levels of IFN-alpha have been found in patients with type 1 diabetes who have detectable levels of coxsackievirus B4 (CVB4) RNA in their blood. The IFN-alpha-inducing activity of CVB4 in vitro is weak but can be enhanced by human IgGs. Therefore, it was investigated in vitro whether a preferential IFN-alpha response of peripheral blood mononuclear cells (PBMCs) to CVB4 exists in patients with type 1 diabetes (n=56) compared with healthy subjects (n=20) and whether antibodies play a role. In patients, the levels of IFN-alpha obtained after stimulation by PBMCs with CVB4 were higher (P=0.008), an individual IFN-alpha response by PBMCs to CVB4 was more frequent (P=0.0004) and increased levels of IFN-alpha were observed in CVB4-infected whole blood cultures. The IFN-alpha-inducing activity of patients plasma and IgGs mixed with CVB4 and then added to PBMCs was high in comparison with healthy subjects (P<0.001) and was inhibited by preincubating the cells with anti-FcgammaRII, anti-FcgammaRIII and anti-CAR (coxsackievirus and adenovirus receptor) antibodies. The strong IFN-alpha responsiveness of PBMCs to CVB4 suggested that IgGs bound to the cell surface might play a role. A short 56 degrees C incubation of PBMCs from patients responsive to CVB4 generated supernatants, which, when added to cells, exhibited IFN-alpha-enhancing activity in combination with CVB4, whereas those of controls did not. Specific antibodies for FcgammaRI, FcgammaRII and CAR inhibited this activity. These studies demonstrate that CVB4, through interactions with circulating and/or cell-bound IgGs, can strongly induce the production of IFN-alpha by PBMCs from patients with type 1 diabetes.

How to diagnose a lipodystrophy syndrome

The spectrum of adipose tissue diseases ranges from obesity to lipodystrophy, and is accompanied by insulin resistance syndrome, which promotes the occurrence of type 2 diabetes, dyslipidemia and cardiovascular complications. Lipodystrophy refers to a group of rare diseases characterized by the generalized or partial absence of adipose tissue, and occurs with or without hypertrophy of adipose tissue in other sites. They are classified as being familial or acquired, and generalized or partial. The genetically determined partial forms usually occur as Dunnigan syndrome, which is a type of laminopathy that can also manifest as muscle, cardiac, neuropathic or progeroid involvement. Gene mutations encoding for PPAR-gamma, Akt2, CIDEC, perilipin and the ZMPSTE 24 enzyme are much more rare. The genetically determined generalized forms are also very rare and are linked to mutations of seipin AGPAT2, FBN1, which is accompanied by Marfan syndrome, or of BANF1, which is characterized by a progeroid syndrome without insulin resistance and with early bone complications. Glycosylation disorders are sometimes involved. Some genetically determined forms have recently been found to be due to autoinflammatory syndromes linked to a proteasome anomaly (PSMB8). They result in a lipodystrophy syndrome that occurs secondarily with fever, dermatosis and panniculitis. Then there are forms that are considered to be acquired. They may be iatrogenic (protease inhibitors in HIV patients, glucocorticosteroids, insulin, graft-versus-host disease, etc.), related to an immune system disease (sequelae of dermatopolymyositis, autoimmune polyendocrine syndromes, particularly associated with type 1 diabetes, Barraquer-Simons and Lawrence syndromes), which are promoted by anomalies of the complement system. Finally, lipomatosis is currently classified as a painful form (adiposis dolorosa or Dercums disease) or benign symmetric multiple form, also known as Launois-Bensaude syndrome or Madelungs disease, which are sometimes related to mitochondrial DNA mutations, but are usually promoted by alcohol. In addition to the medical management of metabolic syndrome and the sometimes surgical treatment of lipodystrophy, recombinant leptin provides hope for genetically determined lipodystrophy syndromes, whereas modifications in antiretroviral treatment and tesamorelin, a GHRH analog, is effective in the metabolic syndrome of HIV patients. Other therapeutic options will undoubtedly be developed, dependent on pathophysiological advances, which today tend to classify genetically determined lipodystrophy as being related to laminopathy or to lipid droplet disorders.

Screening of MAMLD1 Mutations in 70 Children with 46,XY DSD: Identification and Functional Analysis of Two New Mutations

More than 50% of children with severe 46,XY disorders of sex development (DSD) do not have a definitive etiological diagnosis. Besides gonadal dysgenesis, defects in androgen biosynthesis, and abnormalities in androgen sensitivity, the Mastermind-like domain containing 1 (MAMLD1) gene, which was identified as critical for the development of male genitalia, may be implicated. The present study investigated whether MAMLD1 is implicated in cases of severe 46,XY DSD and whether routine sequencing of MAMLD1 should be performed in these patients. Seventy children with severe non-syndromic 46,XY DSD of unknown etiology were studied. One hundred and fifty healthy individuals were included as controls. Direct sequencing of the MAMLD1, AR, SRD5A2 and NR5A1 genes was performed. The transactivation function of the variant MAMLD1 proteins was quantified by the luciferase method. Two new mutations were identified: p.S143X (c.428C>A) in a patient with scrotal hypospadias with microphallus and p.P384L (c.1151C>T) in a patient with penile hypospadias with microphallus. The in vitro functional study confirmed no residual transactivating function of the p.S143X mutant and a significantly reduced transactivation function of the p.P384L protein (p = 0.0032). The p.P359S, p.N662S and p.H347Q variants are also reported with particularly high frequency of the p.359T- p.662G haplotype in the DSD patients. Severe undervirilization in XY newborns can reveal mutations of MAMLD1. MAMLD1 should be routinely sequenced in these patients with otherwise normal AR, SRD5A2 and NR5A1genes.

A part of the VP4 capsid protein exhibited by coxsackievirus B4 E2 is the target of antibodies contained in plasma from patients with type 1 diabetes.

The capsid protein VP4 was identified previously as the target of antibodies contained in plasma enhancing the coxscakievirus B4 (CV‐B4) E2‐induced production of IFN‐α by peripheral blood mononuclear cells (PBMCs). The sequence of VP4 recognized by these antibodies was investigated. This sequence was identified as amino acids 11 to 30 by using synthetic overlapping peptides spanning VP4CV‐B4 E2 in competition experiments for antibodies enhancing the CVB4 E2 induced production of IFN‐α by PBMCs. This amino acid sequence was the major target of anti‐VP4 antibodies according to enzyme‐linked immunosorbent assays (ELISA). There was a positive correlation between the levels of anti‐VP4 and anti‐VP411–30 peptide antibodies detected by ELISA. The levels and the prevalences of these antibodies were significantly higher in patients with type 1 diabetes than in healthy controls. The proportions and the levels of those antibodies in patients were independent of HLA‐DR alleles, age, or presence of ketosis in blood and were not associated with newly or previously diagnosed disease. The VP4CV‐B4 E2 amino acid sequence was submitted to the Swiss‐model in project mode to visualize the possible shape of the sequence of VP4 corresponding to amino acids 11–30 which appeared to be constituted principally by an non‐structured loop. In conclusion, the sequence of VP4 corresponding to amino acids 11–30, or a part of it plays a role in the plasma‐dependent enhancement of CV‐B4 E2‐induced production of IFN‐α by PBMCs, suggesting that at 37°C the virus exhibits that region of VP4 to antibodies. J. Med. Virol. 80:866–878, 2008.

Neonatal screening of congenital adrenal hyperplasia due to 21-hydroxylase deficiency: Lille experience 1980–1996

AIM The results of the neonatal screening of congenital adrenal hyperplasia due to 21-hydroxylase deficiency by 17-hydroxyprogesterone measurement from blood spot on blotting-paper in 408,138 newborns in the French Nord-Pas-de-Calais region from 1980 to 1996 are reported. METHODS This measurement successively used a tracer tritium labelled (RIA H3), 125 iodine (RIA I125), then immunofluorometric method (Delfia). From 1992, sampling was systematically performed at the third day of life. RESULTS Thirty-three cases were detected and confirmed (20 boys and 13 girls). Diagnosis was made before recalling on a clinical basis in three boys and eight girls. In 22 cases (17 boys and five girls) when diagnosis was not made before recalling, it could have been suspected in three girls because of a sex ambiguity once associated with dehydration and in eight boys because of failure to thrive (six times) or a marked dehydration (twice). Lack of sex ambiguity in two girls characterized non classical form of the illness. These two patients benefited from the early detection of the illness on growth data. Out of 49 subjects who died before recall, three could be suspected of bearing 21-hydroxylase deficiency. One single false negative case was found, which led to decrease cut-off value. On the other hand, false positive cases were frequent (0.37%), mainly in premature newborns (88% of cases). CONCLUSION Although decrease of median age for recall at 7 days did not prevent the occurrence of two cases of dehydration, neonatal screening of 21-hydroxylase deficiency appears to be efficient, as far as diagnostic strategy is considered.

Pulsatility of Growth Hormone Secretion and its Relation to Growth

84 short children were submitted to nocturnal spontaneous growth hormone (GH) secretion tests and to provocative insulin-arginine tests. Discrepancies between the GH peak under the provocative test (I-AP) and nocturnal GH maximal peak (PA) and mean concentration (MC) were frequently observed, despite significant statistical correlation between I-AP and PA (r = 0.47; p < 0.02) and between I-AP and MC (r = 0.42; p < 0.02). Night profiles were evaluated by time analysis: 31 fitted a theoretical model, consisting of a cosine function of time (modelizable profiles). Spectral analysis, from Fourier transformation, indicated predominant periods after cluster analysis. The major predominant period in modelizable (n = 9) and in nonmodelizable (n = 28) profiles was close to 180 min and a secondary period was on average 122 min in modelizable (n = 20) and 105 min in nonmodelizable (n = 23) profiles. Two modelizable and two nonmodelizable profiles escaped this classification. The general, auxological and GH secretory status did not differ significantly between patients with modelizable and nonmodelizable profils. Growth velocity correlated with GH mean concentration (r = 0.36; p < 0.001), but not with plasma insulin-like growth factor-I levels nor with any of the pulsatility indices: number of peaks, main period, and pulse height index = mean GH peak/mean GH concentration. The relevance of GH pulsatility to growth is, therefore, unclear in humans.

Monocytes of Patients with Type 1 Diabetes Harbour Enterovirus RNA

Intracellular enterovirus (EV) RNA was detected in blood of patients with type 1 diabetes (T1D). The presence of EV RNA in subsets of peripheral blood mononuclear cells (PBMCs) of patients, and the in vitro infection of these cells with an EV, was investigated.

ASSESSMENT OF THE REPRODUCIBILITY OF NOCTURNAL GROWTH HORMONE SECRETION

The reproducibility of measurements of nocturnal spontaneous secretion of growth hormone (GH) was assessed. The study population consisted of 15 short children with a variety of pathological conditions. Blood samples were taken every 20 min from each subject during sleep on two consecutive nights. The analysis of variance of matched series indicated a global reproducibility, but also demonstrated significant individual variabilities (with-in-subject effect) of both peak amplitude (p = 0.05) and mean concentration (p = 0.02). We did not find any link between the variation of the GH parameters and the variations of the clinical sleep score in 11 patients.