Category: Viruses

Human herpesviruses in chronic fatigue syndrome

Abstract:

We have conducted a double-blind study to assess the possible involvement of the human herpesviruses (HHVs) HHV6, HHV7, Epstein-Barr virus (EBV), and cytomegalovirus in chronic fatigue syndrome (CFS) patients compared to age-, race-, and gender-matched controls.

The CFS patient population was composed of rigorously screened civilian and Persian Gulf War veterans meeting the Centers for Disease Control and Prevention’s CFS case definition criteria. Healthy control civilian and veteran populations had no evidence of CFS or any other exclusionary medical or psychiatric condition. Patient peripheral blood mononuclear cells were analyzed by PCR for the presence of these HHVs.

Using two-tailed Fisher’s exact test analyses, we were unable to ascertain any statistically significant differences between the CFS patient and control populations in terms of the detection of one or more of these viruses. This observation was upheld when the CFS populations were further stratified with regard to the presence or absence of major axis I psychopathology and patient self-reported gradual versus acute onset of disease. In tandem, we performed serological analyses of serum anti-EBV and anti-HHV6 antibody titers and found no significant differences between the CFS and control patients.

 

Source: Wallace HL 2nd, Natelson B, Gause W, Hay J. Human herpesviruses in chronic fatigue syndrome. Clin Diagn Lab Immunol. 1999 Mar;6(2):216-23. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC95690/ (Full article)

 

Propagation and characterization of human herpesvirus-7 (HHV-7) isolates in a continuous T-lymphoblastoid cell line (SupT1)

Abstract:

After initial culture of HHV-7 in PHA-stimulated human cord blood mononuclear cells (HCBMC), six HHV-7 isolates were propagated successfully in an immature continuous T-lymphoblastoid cell line SupT1. All six isolates infected efficiently the SupT1 cells, and the infected cells became grossly enlarged and multinucleated 7-21 days post-infection. Various stages of HHV-7 morphogenesis were detected.

Cell-free supernatants from HHV-7-infected SupT1 cells were infectious to HCBMC as well as to SupT1 cells. The HHV-7-infected SupT1 and HCBMC cell lysates contained more infectious virus than the centrifuged cell culture fluid supernates from the same culture. The HHV-7 isolates H7-2, H7-3, JHC, and JB, concentrated 500 times, had average infectivity titers of 10(3.0) TCID50/ml while strains H7-4 and KHR titered approximately 1-2 logs higher. When all six HHV-7 isolates were propagated in SupT1 and culture fluid supernatants were examined 14-21 days post-infection by negative stain electron microscopy they contained an average of 1.9 x 10(9) virus particles/liter.

IFA and ELISA, using HHV-7/SupT1 cell lysate as an antigen, seem to correlate well in detecting high and low HHV-7 antibody in sera from chronic fatigue patients and healthy donors as controls. HHV-7 from SupT1 cell culture was free of HHV-6 and other human herpesviruses as tested by PCR, and the HHV-7 PCR signal was still strong when the viral preparation was diluted to 4.82 x 10(2) genome copies.

Since HCBMC are expensive to obtain and available in only small amounts, it is difficult to obtain large quantities of HHV-7 antigen. On the other hand, the SupT1 cell is an excellent source to produce consistently sufficient quantities of HHV-7 for purification studies, development of immunodiagnostics, in vivo infectivity studies, evaluation of antiviral drugs, and molecular biological studies.

 

Source: Ablashi DV, Handy M, Bernbaum J, Chatlynne LG, Lapps W, Kramarsky B, Berneman ZN, Komaroff AL, Whitman JE. Propagation and characterization of human herpesvirus-7 (HHV-7) isolates in a continuous T-lymphoblastoid cell line (SupT1). J Virol Methods. 1998 Aug;73(2):123-40. http://www.ncbi.nlm.nih.gov/pubmed/9766884

 

Cellular sequences in stealth viruses

Abstract:

Cloned DNA obtained from the culture of an African green monkey simian cytomegalovirus-derived stealth virus contains multiple discrete regions of significant sequence homology (p values ranging from 4 x 10(-3) to 1 x 10(-20)) to portions of known human cellular genes. The stealth virus was cultured from a patient with chronic fatigue syndrome (CFS).

Earlier studies had revealed considerable sequence heterogeneity within DNA fragments isolated from virus-infected cells. A set of polymerase chain reaction (PCR) primers generated different PCR products when tested on stealth virus cultures from 4 patients with CFS. Several of the PCR products also contain regions of significant partial homology to distinct cellular sequences, including sequences repetitively expressed throughout the cellular genome.

Stealth viruses may play an important role in the origins and in the genetic diversity of both viral and cellular sequences.

 

Source: Martin WJ. Cellular sequences in stealth viruses. Pathobiology. 1998;66(2):53-8. http://www.ncbi.nlm.nih.gov/pubmed/9645627

 

High prevalence without reactivation of herpes virus 6 in subjects with chronic fatigue syndrome

Abstract:

INTRODUCTION: Chronic fatigue syndrome (CFS) is a disorder of unknown etiology. Some viruses have been associated with CFS etiology, specially herpesviruses, enteroviruses and retroviruses. Some studies suggest an association between human herpesvirus-6 (HHV-6) and CFS. In order to know if there is an active HHV-6 infection in CFS patients we studied the immunologic and virologic status of HHV-6.

MATERIALS AND METHODS: Twenty patients with CFS were studied. IgG and IgM anti HHV-6 were determined by indirect immunofluorescence assay. DNA from serum and peripheral blood mononuclear cells (PBMC) were studied by dot- and Southern-blotting and nested-PCR to detect HHV-6 DNA. HHV-6 RNA from PBMC were amplified by RT(retrotranscription)-PCR.

RESULTS: Ten patients (50%) had IgG anti-HHV-6 in serum but none had IgM anti-HHV-6. Dot-blotting of DNA from 200 microliters of serum and Southern-blotting of 10 micrograms of PBMC DNA were negative. Nested-PCR from sera were negative. Nested-PCR with 1 microgram PBMC DNA were positive in 8 out 20 (40%) and with 5 micrograms PBMC DNA were positive in 16 out of 20 (80%). No viral RNA were detected in PBMC.

CONCLUSIONS: There is a high proportion of CFS patients infected with HHV-6 but with low viral load. Results do not support HHV-6 reactivation in CFS patients.

 

Source: Cuende JI, Civeira P, Diez N, Prieto J. High prevalence without reactivation of herpes virus 6 in subjects with chronic fatigue syndrome. An Med Interna. 1997 Sep;14(9):441-4. [Article in Spanish] http://www.ncbi.nlm.nih.gov/pubmed/9453750

 

Demonstration on Borna disease virus in patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS), a recently named heterogeneous disorder, is an illness of unknown etiology. The association between CFS and several viral infection has been suggested. Here, we centered on the possible link between CFS and Borna disease virus (BDV) infection.

BDV is a neurotropic, nonsegmented negative-strand (NNS) RNA virus. Recent epidemiological data have suggested that BDV may be closely associated with depression and schizophrenia in humans.

In Japanese patients with CFS, the prevalence of BDV infection was 34% (30/89) and 12% (7/57) by immunoblotting and PCR analysis, respectively. Furthermore, anti-BDV antibodies and BDV RNA were detected in a family cluster with CFS. These results suggested that this virus contributes to or initiates CFS, although the single etiologic role of BDV is unlikely.

 

Source: Nakaya T, Kuratsune H, Kitani T, Ikuta K. Demonstration on Borna disease virus in patients with chronic fatigue syndrome. Nihon Rinsho. 1997 Nov;55(11):3064-71. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/9396313

 

Enterovirus infections in new disguise

Abstract:

Enteroviruses (Coxsackie A and B, echovirus, poliovirus) belong to a group of small RNA-viruses, picomavirus, which are widespread in nature. Enteroviruses cause a number of well known diseases and symptoms in humans, from subclinical infections and the common cold to poliomyelitis with paralysis. The development of polio vaccines is the greatest accomplishment within the field of enterovirus research and the background work was awarded the Nobel prize in 1954. New knowledge implies that enteroviruses play a more important part in the morbidity panorama than was previously thought. Chronic (persistent) enteroviruses were formerly unknown.

Serologic and molecular biology techniques have now demonstrated that enteroviral genomes, in certain situations, persist after the primary infection (which is often silent). Persistent enteroviral infection or recurrent infections and/or virus-stimulated autoimmunity might contribute to the development of diseases with hitherto unexplained pathogenesis, such as post polio syndrome, dilated cardiomyopathy, juvenile (type 1) diabetes and possibly some cases of chronic fatigue syndrome.

 

Source: Fohlman J, Friman G, Tuvemo T. Enterovirus infections in new disguise. Lakartidningen. 1997 Jul 9;94(28-29):2555-60. [Article in Swedish] http://www.ncbi.nlm.nih.gov/pubmed/9254324

 

Chronic parvovirus B19 infection resulting in chronic fatigue syndrome: case history and review

Abstract:

The spectrum of disease caused by parvovirus B19 has been expanding in recent years because of improved and more sensitive methods of detection. There is evidence to suggest that chronic infection occurs in patients who are not detectably immunosuppressed.

We report the case of a young woman with recurrent fever and a syndrome indistinguishable from chronic fatigue syndrome. After extensive investigation, we found persistent parvovirus B19 viremia, which was detectable by polymerase chain reaction (PCR) despite the presence of IgM and IgG antibodies to parvovirus B19.

Testing of samples from this patient suggested that in some low viremic states parvovirus B19 DNA is detectable by nested PCR in plasma but not in serum. The patient’s fever resolved with the administration of intravenous immunoglobulin.

 

Source: Jacobson SK, Daly JS, Thorne GM, McIntosh K. Chronic parvovirus B19 infection resulting in chronic fatigue syndrome: case history and review. Clin Infect Dis. 1997 Jun;24(6):1048-51. http://cid.oxfordjournals.org/content/24/6/1048.long (Full article)

 

Lack of association of Borna disease virus and human T-cell leukemia virus type 1 infections with psychiatric disorders among Japanese patients

Abstract:

Borna disease virus (BDV) infection has been suspected to be a possible etiological factor in human psychiatric disorders and recently in chronic fatigue syndrome. Evidence of the correlation of BDV infection with these disorders remained unclear. Kagoshima is known to be one of the major areas in which human T-cell leukemia virus type 1 (HTLV-1) is endemic; this is the first isolated human retrovirus that causes adult T-cell leukemia with neurological symptoms. The present study aimed to clarify whether BDV and HTLV-1 infections are associated with psychiatric disorders among Japanese patients.

Subjects were 346 patients with psychiatric disorders (schizophrenia, 179; mood disorder, 123; and others, 44) and 70 healthy controls. Anti-BDV antibodies from plasma samples were screened by the indirect immunofluorescence (IF) method using BDV-infected MDCK cells. Results revealed that only three samples were found to be weakly positive for BDV in the IF assay and seronegative by Western blot (immunoblot) assay.

Furthermore, BDV-p24 related RNA in peripheral blood mononuclear cells from 106 of 346 psychiatric patients and 12 or 70 healthy controls by p24-reverse transcription PCR was examined. Two mood disorder patients were positive for BDV-p24 RNA but seronegative. To detect anti-HTLV-1 antibodies the plasma samples were screened by the particle agglutination method and no significant difference in seropositivity for anti-HTLV-1 antibody was found between the patients and healthy controls.

These results also suggested that there is a lack of association between BDV and HTLV-1 infections with psychiatric disorders among Japanese patients.

 

Source: Kubo K, Fujiyoshi T, Yokoyama MM, Kamei K, Richt JA, Kitze B, Herzog S, Takigawa M, Sonoda S. Lack of association of Borna disease virus and human T-cell leukemia virus type 1 infections with psychiatric disorders among Japanese patients. Clin Diagn Lab Immunol. 1997 Mar;4(2):189-94. http://www.ncbi.nlm.nih.gov/pubmed/9067654

 

Evidence for enteroviral persistence in humans

Abstract:

We have sought evidence of enteroviral persistence in humans. Eight individuals with chronic fatigue syndrome (CFS) were positive for enteroviral sequences, detected by PCR in two serum samples taken at least 5 months apart. The nucleotide sequence of the 5′ non-translated region (bases 174-423) was determined for each amplicon.

Four individuals had virtually identical nucleotide sequences ( > 97%) in both samples. The sequence pairs also each had a unique shared pattern indicating that the virus had persisted. In one individual (HO), it was clear that there had been infection with two different enteroviruses.

In the remaining three individuals, the lack of unique shared features suggested that re-infection had occurred, rather than persistence. With the exception of HO, the sequences fell into a subgroup that is related to the Coxsackie B-like viruses.

 

Source: Galbraith DN, Nairn C, Clements GB. Evidence for enteroviral persistence in humans. J Gen Virol. 1997 Feb;78 ( Pt 2):307-12. http://www.ncbi.nlm.nih.gov/pubmed/9018051

 

Electron microscopic immunocytological profiles in chronic fatigue syndrome

Abstract:

Structures consistent in size, shape and character with various stages of a Lentivirus replicative cycle were observed by electron microscopy in 12-day peripheral-blood lymphocyte cultures from 10 of 17 Chronic Fatigue Syndrome patients and not in controls. Attempts to identify a lymphoid phenotype containing these structures by immunogold labelling failed and the results of reverse-transcriptase assay of culture supernatants were equivocal. The study was blind and case-controlled, patients being paired with age, sex and ethnically matched healthy volunteers. Prescreening of subjects included the common metabolic and immunological disorders, functional conditions and a virus-screen against hepatitis B and C, Epstein-Barr Virus, Cytomegalovirus and Human Immunodeficiency Virus.

 

Source: Holmes MJ, Diack DS, Easingwood RA, Cross JP, Carlisle B. Electron microscopic immunocytological profiles in chronic fatigue syndrome. J Psychiatr Res. 1997 Jan-Feb;31(1):115-22. http://www.ncbi.nlm.nih.gov/pubmed/9201653