Quantification of Active and Latent Form of Human Cytomegalovirus Infection in Umbilical Cord Blood Donors by Real-Time PCR

BACKGROUND

Umbilical cord blood (UCB) is believed to be a highly valuable source of hematopoietic stem cells for transplantation. Objective: To investigate the prevalence of active and latent human cytomegalovirus (CMV) infection in UCB donors in Iranian population.

METHODS

A total of 825 UCB samples was collected under standard procedures and analyzed for the presence of CMV DNAs in buffy coat (latent infection) and plasma (active infection). DNA was extracted from buffy coat and plasma samples separately and tested with quantitative real-time PCR. All positive samples were checked by ELISA for IgG and IgM anti-CMV antibody.

RESULTS

Latent CMV infection was detected in 17 (2%) buffy coat samples with a low level of viral load, which indicated the presence of latent viral infection in donors. None of the plasma samples were found positive for CMV DNA reflecting no active infection. In the 17 positive samples, CMV viral load was 91-104 (mean: 100) copies/mL. All samples positive for viral DNA were also found positive for CMV IgG antibody by ELISA. No CMV IgM antibody was detected in positive samples.

CONCLUSION

CMV is still the most important virus that infects hematopoietic stem cells and could be dangerous, especially for immunocompromized transplant recipients. We therefore suggest using real-time PCR for the detection and quantification of the viral DNA in buffy coat and plasma of UCB donors. PCR of plasma for detection of CMV and antibody assay for CMV infection add no more sensitivity for the detection of latent CMV infection in UCB donors.

Quantitative polymerase chain reaction for detection of human herpesvirus-7 infection in umbilical cord blood donors

OBJECTIVE

Umbilical cord blood (UCB) has been a reasonable alternative to granulocyte colony-stimulating factor-mobilized peripheral blood or bone marrow, as a source of hematopoietic stem cells with a lower risk of graft-versus-host disease. In immunocompromised hosts after transplantation, the risk of viral infection in adults, especially with beta-herpesviruses such as human herpesvirus-7 (HHV-7), may be increased. This virus in immunocompromised patients can be reactivated from latency and converted to an active phase. Therefore, light-upon-extension real-time polymerase chain reaction (PCR) was developed to assess the prevalence and load of HHV-7 in the plasma and buffy coat of donors.

METHODS

About 825 UCB samples under standard protocol from donors were collected. Then, DNA from plasma and buffy coat was extracted and quantitative real-time PCR was performed with light-upon-extension primers.

RESULTS

Overall, HHV-7 was detected in 3.64% (30/825) of UCB donors. HHV-7 DNA was detected in 26 (3.2%) buffy coat samples (latent infection), and only 4 (0.48%) of them were positive for HHV-7 DNA in plasma samples (active infection); the mean HHV-7 viral load was 1.31 × 10(1) copies/mL in latent infection, and 1.94 × 10(5) copies/mL in active infection.

CONCLUSIONS

We suggest that real-time PCR in plasma and buffy coat could be a useful method to detect active and latent HHV-7 infection in UCB donors and determine its role in subsequent transmission events.

Prevalence of intestinal parasites in bakery workers in khorramabad, lorestan iran

BACKGROUND

Food contamination may occur through production, processing, distribution and preparation. In Iran especially in Khorramabad, 33° 29' 16" North, 48° 21' 21" East, due to kind of nutrition, culture and economic status of people, bread is a part of the main meal and the consumption of bread is high. In this study, the bakery workers were studied for determining of intestinal parasites prevalence.

METHODS

The study was carried out during September to November 2010 in Khorramabad. All the 278 bakeries and the bakery workers including 816 people were studied in a census method and their feces were examined for the presence of parasites by direct wet-mount, Lugol's iodine solution, and formaldehyde-ether sedimentation, trichrome staining, and single round PCR (For discrimination of Entamoeba spp).

RESULTS

Ninety-six (11.9%) stool specimens were positive for different intestinal parasites. Intestinal parasites included Giardia lamblia 3.7%, Entamoeba coli 5.5%, Blastocystis sp. 2.1%, Entamoeba dispar 0.4%, Hymenolepis nana 0.1%, and Blastocystis sp. 0.1%.

CONCLUSION

In order to reduce the contamination in these persons, some cases such as stool exam every three months with concentration methods, supervision and application of accurate health rules by health experts, training in transmission of parasites are recommended.

A flow cytometric opsonophagocytic assay for measurement of functional antibodies elicited after immunization with outer membrane vesicle of Neisseria meningitidis serogroup B

Opsonophagocytosis mediated by antibody and complement is the major defense mechanism for clearing Neisseria meningitidis from the host. Therefore, a newly developed phagocytosis assay based on flow cytometry (flow assay) was using sera obtained from rabbit postvaccination with outer membrane vesicle of N. meningitidis serogroup B, was done in order to evaluation of the potential efficacy of (experimental) meningococcal vaccines. The Outer Membrane Vesicles (OMVs) and control were injected intramuscularly into groups of five rabbit with boosters on 14, 28 and 42 days after the primary immunization. The serum on 0, 14, 28, 42 and 56 days were collected and stored at -20 degrees C for next analysis. Phagocytic function of and intracellular oxidative burst generation by rabbit polymorphonuclear (PMN), against N. meningitidis serogroup B, was measured with flow cytometer, using dihydrorhodamine-123 as probes, respectively. We use a Coulter Epics XL-profile (USA) with an argon laser operating at 488 nm. The results of quantitative flow cytometric analysis of rabbit PMN function in hyperimmun sera with OMVs revealed a highly significant increase in opsonophagocytic responses against serogroup B meningococci after 56 day in comparison with the control group (p < 0.05). Present results indicated that OMVs could be as a candidate for vaccine toward serogroup B meningococci and a new standard flow cytometric method to measure the opsonophagocytosis activity by rabbit PMNs was shown by this study.