Sex-Related Differences in Cerebrospinal Fluid Plasma-Derived Proteins of Neurological Patients.

BACKGROUND AND AIMS: Cerebrospinal fluid (CSF) protein content presents a sexual dimorphism in humans. We investigated sex-related differences in CSF IgG levels and in the quantification of intrathecal IgG synthesis (IIS). METHODS: CSF, serum albumin and IgG were measured in 1519 neurological patients and both linear and hyperbolic formulas were used for the quantification of IIS. CSF-restricted oligoclonal IgG bands (OCBs) were used as "gold standard". RESULTS: The linear IgG Index showed a weak agreement with OCBs in males and females (k = 0.559, k = 0.587, respectively), while the hyperbolic Reiber's formulas had a moderate agreement with OCBs in females (k = 0.635) and a weak agreement in males (k = 0.565). Higher CSF albumin and IgG levels were found in men than in women in the whole population and in subjects without IIS after adjusting for age and for serum concentrations of albumin and IgG, respectively (Quade statistics, p < 0.000001). CSF and serum albumin and IgG levels positively correlated to age in both sexes. CSF total protein content did not correlate with CSF leukocyte numbers but was higher in patients with marked pleocytosis. CONCLUSIONS: In neurological patients, men have higher levels of CSF serum-derived proteins, such as albumin and IgG.

Guidance for faecal occult blood testing: quantitative immunochemical method (FIT-HB) in colorectal cancer screening programmes. / Guida per la determinazione del sangue occulto fecale: metodo immunochimico quantitativo (FIT-HB) nei programmi di screening per il carcinoma colorettale

BACKGROUND: in Italy, colorectal cancer screening is included as part of the Italian National Health Service - SSN (Servizio Sanitario Nazionale) Essential Levels of Care - LEA (Livelli Essenziali Assistenziali) and the European Guidelines, which specify quantitative FIT-Hb testing as the best strategy for organised screening programmes. To ensure consistent operating standards in Member States, European regulations require the implementation of certification and accreditation requirements for diagnostic and care-related processes. The requirement, based on ISO 17021 accreditation standards, includes ISO 9001 certification for systems and ISO 15189:2012 accreditation for laboratories. METHODOLOGY: various phases of the analytical process (pre-test, test, post-test) were evaluated in detail and provided operational guidelines for adjusting analytical and managerial procedures using: (a) feedback from members of GISCoR screening labs; (b) performance data obtained via a systematic review of the literature and the Osservatorio Nazionale Screening (ONS) Survey; (c) recommendations for laboratory practice issued by the World Endoscopy Organization "FIT for Screening" Working Group; (d) selected guidelines from the National Guidelines Clearinghouse database; and (e) Canadian, Australian and European screening programme websites. With respect to ISO 15189:2012 standards for accreditation of medical laboratories, GISCoR's guidance has been re-evaluated and revised by auditors from the Italian certification body (ACCREDIA) to assess its compliance and completeness with the aim of finalising operating procedures. CONCLUSIONS: the implementation and maintenance of operational standards required by complex systems (e.g. screening programmes) involving constant interaction between facilities and the supporting organisational structure are not easy to achieve. The guide aims to provide laboratories with the necessary guidance for proper process management.

Human herpesvirus 6 (HHV-6) U94/REP protein inhibits betaherpesvirus replication.

Human herpesvirus 6 (HHV-6) is the only human herpesvirus encoding U94/rep, homologue to the parvovirus non-structural gene rep68/78. Results to date suggest that HHV-6 U94/rep might regulate viral gene expression and have a role in viral latency. To determine the effect of U94/REP upon viral replication, the protein was produced. The purified U94/REP retained the characteristic immunological features. It was internalized and localized in the nucleus of human cells, showing marked inhibitory activity on the replication of HHV-6 (both variants A and B). The effect of U94/REP was dose-dependent and sensitive to treatment with single-stranded but not double-stranded DNA. U94/REP inhibited the replication of other betaherpesviruses, HHV-7 and human cytomegalovirus, but had no effect on herpes simplex virus. These results confirm the action of U94/rep latency gene in the regulation of HHV-6 replication with implications for co-reactivations and latency of human betaherpesviruses.

Detection of antibodies directed against human herpesvirus 6 U94/REP in sera of patients affected by multiple sclerosis.

The association between human herpesvirus 6 (HHV-6) and multiple sclerosis (MS) is controversial. In fact, it is difficult to establish a causative role of HHV-6, due to the high prevalence of latently infected individuals in the healthy population. Therefore, the presence of virus sequences in tissue biopsy does not support a viral role, and serological assays do not show significant differences between MS patients and control populations. The only viral gene expressed during latency is U94/rep. Therefore, we have developed a serological assay for the detection of antibodies specifically directed against U94/REP protein. Different populations were analyzed by enzyme-linked immunosorbent assay, including healthy controls, MS patients, and subjects with diseases unrelated to HHV-6 infection, including other neurological diseases. The results show statistically significant differences (P > 0.01) between MS patients and control groups, both in antibody prevalence (87 and 43.9%, respectively) and in geometric mean titer (1:515 and 1:190, respectively). The detection of antibodies specific for HHV-6 U94/REP shows that the immune system is exposed to this antigen during natural infection. The higher prevalence and higher titers of antibodies to U94/REP suggest that MS patients and control groups might experience different exposures to HHV-6.