Differential Marker Expression between Keratinocyte Stem Cells and Their Progeny Generated from a Single Colony.

The stemness in keratinocyte stem cells (KSCs) is determined by their gene expression patterns. KSCs are crucial in maintaining epidermal homeostasis and wound repair and are widely used candidates for therapeutic applications. Although several studies have reported their positive identifiers, unique biomarkers for KSCs remain elusive. Here, we aim to identify potential candidate stem cell markers. Human epidermal keratinocytes (HEKs) from neonatal foreskin tissues were isolated and cultured. Single-cell clonal analysis identified and characterized three types of cells: KSCs (holoclones), transient amplifying cells (TACs; meroclones), and differentiated cells (DSCs; paraclones). The clonogenic potential of KSCs demonstrated the highest proliferation potential of KSCs, followed by TACs and DSCs, respectively. Whole-transcriptome analysis using microarray technology unraveled the molecular signatures of these cells. These results were validated by quantitative real-time polymerase chain reaction and flow cytometry analysis. A total of 301 signature upregulated and 149 downregulated differentially expressed genes (DEGs) were identified in the KSCs, compared to TACs and DSCs. Furthermore, DEG analyses revealed new sets of genes related to cell proliferation, cell adhesion, surface makers, and regulatory factors. In conclusion, this study provides a useful source of information for the identification of potential SC-specific candidate markers.

Emerging OP354-Like P[8] Rotaviruses Have Rapidly Dispersed from Asia to Other Continents.

The majority of human group A rotaviruses possess the P[8] VP4 genotype. Recently, a genetically distinct subtype of the P[8] genotype, also known as OP354-like P[8] or lineage P[8]-4, emerged in several countries. However, it is unclear for how long the OP354-like P[8] gene has been circulating in humans and how it has spread. In a global collaborative effort 98 (near-)complete OP354-like P[8] VP4 sequences were obtained and used for phylogeographic analysis to determine the viral migration patterns. During the sampling period, 1988-2012, we found that South and East Asia acted as a source from which strains with the OP354-like P[8] gene were seeded to Africa, Europe, and North America. The time to the most recent common ancestor (TMRCA) of all OP354-like P[8] genes was estimated at 1987. However, most OP354-like P[8] strains were found in three main clusters with TMRCAs estimated between 1996 and 2001. The VP7 gene segment of OP354-like P[8] strains showed evidence of frequent reassortment, even in localized epidemics, suggesting that OP354-like P[8] genes behave in a similar manner on the evolutionary level as other P[8] subtypes. The results of this study suggest that OP354-like P[8] strains have been able to disperse globally in a relatively short time period. This, in combination with a relatively large genetic distance to other P[8] subtypes, might result in a lower vaccine effectiveness, underscoring the need for a continued surveillance of OP354-like P[8] strains, especially in countries where rotavirus vaccination programs are in place.

Genotypes of rotavirus strains circulating in Amman, Jordan, in 2006/07 and their significance for the potential effectiveness of future rotavirus vaccination.

The prevalence, seasonality and genotypes of rotavirus circulating in Jordan were determined to provide data useful for the implementation of a rotavirus vaccine in the national childhood vaccination program. During 2006/07, rotavirus was detected in 35% of hospitalized children, and 88% of the cases occurred in children aged between 6 and 23 months. Rotavirus infection persisted throughout the year and peaked in winter. Seven genotypes were identified by RT-PCR and sequencing: G1P[8], G9P[8], G2P[4], G1P[4], G3P[8], G4P[8] and G9P[6], which represented 69%, 8.8%, 2.4%, 2.0%, 1.2%, 0.4% and 0.4% of the rotavirus strains, respectively. Thirteen percent and 2.8% of the total strains were partially typed or untypeable, respectively. Eighty-eight percent and 12% of the rotavirus strains possessed a long and short electropherotype, respectively. As more than 90% of the rotavirus strains circulating in Jordan possessed the G1 or P[8]-genotype, it is concluded that the implementation of the rotavirus vaccine in the framework of the national childhood vaccination program of Jordan would most likely be very effective. Continuous monitoring of the currently circulating genotypes in Jordan should be encouraged.

The Molecular Epidemiology and Phylogeny of Torque Teno Virus (TTV) in Jordan.

Torque teno virus (TTV) is the most common component of the human blood virobiota. Little is known, however, about the prevalence of TTV in humans and the most common farm domesticates in Jordan, or the history and modality of TTV transmission across species lines. We therefore tested sera from 396 Jordanians and 171 farm animals for the presence of TTV DNA using nested 5'-UTR-PCR. We then performed phylogenetic, ordination and evolutionary diversity analyses on detected DNA sequences. We detected a very high prevalence of TTV in Jordanians (~96%); much higher than in farm animal domesticates (~29% pooled over species). TTV prevalence in the human participants is not associated with geography, demography or physical attributes. Phylogenetic, ordination and evolutionary diversity analyses indicated that TTV is transmitted readily between humans across the geography of the country and between various species of animal domesticates. However, the majority of animal TTV isolates seem to derive from a single human-to-animal transmission event in the past, and current human-animal transmission in either direction is relatively rare. In conclusion, animal TTV in Jordan is historically derived from human variants; however, ongoing human-animal TTV exchange is minimal and zoonotic infection seems to be of limited importance.

Detection of enterotoxin genes seg, seh, sei, and sej and of a novel aroA genotype in Jordanian clinical isolates of Staphylococcus aureus.

The presence of staphylococcal enterotoxin (SE) genes (seg, seh, sei, and sej) and the correlation of their prevalence with the genotypes were studied in 100 clinical isolates of Staphylococcus aureus. Polymerase chain reaction (PCR) of SE genes indicated that 39% of the isolates were enterotoxigenic. Thirty-seven percent of the total isolates were seg positive, whereas 24% and 4% were sei and seh positive, respectively. All isolates containing sei were positive for seg, whereas sej gene was not detected. Genotyping by PCR-restriction fragment length polymorphism analysis of the aroA gene revealed that 39% of the isolates were type A and 11% were type B, and 50% displayed a novel (N) genotype. The presence of the enterotoxin genes was independent (P < 0.05) of the genotypes of the tested S. aureus isolates. This study has demonstrated that the seg was the most dominant enterotoxin gene and that the enterotoxigenic Jordanian S. aureus isolates belong to different genotypes, and N genotype was predominant.

Enterotoxicity and genetic variation among clinical Staphylococcus aureus isolates in Jordan.

A total of 100 Jordanian clinical Staphylococcus aureus isolates was analysed for the presence of the enterotoxin genes sea, seb, sec, sed and see using multiplex PCR. Twenty-three isolates (23 %) were potentially enterotoxigenic. The prevalence of sea, sec and sea plus sec among the total clinical isolates was 15, 4 and 4 %, respectively. None of the isolates harboured sed, seb or see genes. S. aureus isolates were subjected to DNA fingerprinting by randomly amplified polymorphic DNA (RAPD) analysis to test whether isolates harbouring the toxin genes were genetically clustered. A total of 13 genotypes was identified at a 47 % similarity level. Genotypes I and V accounted for the largest number of enterotoxigenic isolates (19 %). This study has demonstrated the genetic diversity of Jordanian clinical S. aureus isolates and shown that the presence of the toxin genes is not genotype specific.

Mumps: immune status of adults and epidemiology as a necessary background for choice of vaccination strategy in Jordan.

The prevalence of antibodies against mumps in 333 students at Jordan University was assessed using the ELISA technique. Most of the students (93.7%) were seropositive for mumps. About 50% of unvaccinated students and students vaccinated using the optional single-dose MMR vaccine had mumps. The incidence rate of mumps in different age groups and sexes, the geographic distribution and the seasonality of mumps infection prior to the adoption of compulsory MMR vaccination were investigated during the period from 1988 to 2000. Mumps occurred in all age groups in both sexes and the incidence rate was higher in children aged 5-14 years than in adults. There was a higher frequency in winter and spring with epidemic peaks in 1988, 1993 and 2000. Southern Jordan had the highest incidence rate due to low vaccination coverage by the private clinics. The data support the introduction of compulsory MMR vaccination in Jordan for all susceptible individuals. Evaluation of the effectiveness of the compulsory single-dose vaccine and, based on the outcome, a second dose of this vaccine is also recommended in order to achieve and maintain a high level of immunization.

Antibiotic resistance patterns of mecA-positive Staphylococcus aureus isolates from clinical specimens and nasal carriage.

The present study demonstrates that the nasal carriage rate of Staphylococcus aureus was 40% in Jordanian healthy young adult population, and 19% of nasal S. aureus and 57% of clinical isolates over the same period were resistant to oxacillin (MRSA), respectively. The mecA gene was detected in all MRSA isolates in both groups. Most of MRSA isolates were multiresistant to three antibiotic classes (beta-lactams, aminoglycosides, macrolides-lincosamides). This result suggests a serious problem may be encountered in treatment of staphylococcal infections in Jordan.

Hepatitis C virus infection in Jordanian haemodialysis units: serological diagnosis and genotyping.

The seroprevalence and genotypes of hepatitis C virus (HCV) were studied in 283 patients attending six haemodialysis units in Jordan. In all, 98 (34.6%) patients were anti-HCV-positive by EIA, 92 (93.9%) of whom were also reactive in an immunoblot assay. The prevalence of anti-HCV was correlated with a history of blood transfusion before the introduction of blood donor screening for HCV and with duration of haemodialysis. HCV RNA was detected in 30 (30.6%) of 98 anti-HCV-positive sera. HCV viraemia was not associated with a particular antibody for the six HCV antigens studied by the immunoblot assay, although reactivity to the core antigens was greater in the HCV RNA-positive sera than in negative sera. Two HCV genotypes (1 and 4) were identified for the first time in Jordan by restriction fragment length polymorphism analysis of HCV 5'-NCR. The predominant genotype was HCV la (12 of 30). Genotypes lb and 4 were detected in 10 and 8 patients, respectively. The antibody response to HCV antigens was genotype-dependent, with a wider range of antibody specificities detected in the immunoblot assay in the 12 patients with genotype 1a infection than in the 8 patients with genotype 4. However, there was no significant difference in the prevalence of antibodies to HCV antigens among patients infected with either genotype 1a or lb. In conclusion, the prevalence of anti-HCV, blood transfusion, duration of dialysis and HCV genotypes suggest possible nosocomial HCV transmission among patients which needs confirmation by phylogenetic analysis of subgenomic HCV regions.

Risk of perinatal transmission of rubella and parvovirus B19 in Jordanian pregnant women.

The seroprevalence and the risk of perinatal transmission of rubella virus (RV) and human parvovirus B19 were assessed in 439 Jordanian pregnant women. Seroprevalence data indicate that 43.7%, 48.7% and 19% of women are susceptible to RV, parvovirus B19 infections and both, respectively. A total of 12.2% and 20.2% of RV susceptible women are at the first and second trimester of gestation, respectively. They are at risk of bearing infants with congenital rubella syndrome (CRS). However, 15% and 23% of parvovirus B19 susceptible women are at the first and second trimester of gestation, respectively. They are at risk of fetal loss or hydrops fetalis. Prenatal screening for these viruses, postpartum MMR vaccination and parvovirus B19 passive immunization are recommended.

Epidemiology and clinical characteristics of respiratory syncytial virus infections in Jordan.

This study was carried out to determine the prevalence, seasonal distribution of RSV, the signs and symptoms associated with it in Jordan. A total of 200 nasopharyngeal aspirates were obtained from hospitalized children (below 2 years old). RSV was detected in 12.5% of patients using direct immunofluorescence technique. Most infections were associated with bronchilolitis, and higher rates of hypoxemia, retractions, tachypnea, hyperinflation and interstitial infiltrates in 1 to 3 months old children. RSV showed a clear temporal periodicity. The epidemic began in December and disappeared in March with a peak of incidence during February 2003 and January 2004. The seasonal distribution showed a significant correlation with temperature, rainfall and relative humidity. This study provides further information on RSV epidemiology which could help in planning of prevention and control programs in Jordan, distinguishing RSV infections on the basis of the clinical picture and considering RSV between December and March each year.

Risk of perinatal transmission of hepatitis B virus in Jordan.

OBJECTIVES: To determine the risk of perinatal transmission of hepatitis B virus (HBV) in Jordan. METHODS: Plasma samples from 1000 pregnant Jordanian women were screened by ELISA for HBV markers (HBsAg, HBeAg, anti-HBe, anti-HBc and anti-HBs). RESULTS: HBsAg and HBeAg were detected in 4.3% and 0.1% of the pregnant women, respectively. The overall prevalence of antibodies was 6%, 11.1% and 7.5% for anti-HBe, anti-HBc and anti-HBs, respectively. Women were assigned to four groups according to the serological patterns of HBV markers: susceptible (85.9%), with acute infection (2.9%), with chronic infection (1.4%) and previously infected (9.8%). Most women were at the third trimester of pregnancy, therefore women with acute and chronic hepatitis at this gestational age were at risk of transmitting HBV infection to their newborns. Women who belonged to the low socio-economic class were at higher risk of HBV infection. CONCLUSIONS: Based on the results, we recommend screening women for HBV during pregnancy in order to identify HBV carriers. All newborns born to carriers should be vaccinated immediately after birth, both passively and actively. Also vaccination of HBV seronegative pregnant women is recommended.