Hepatitis B virus genotype D predominates HBsAg-positive egyptian blood donors and is mainly associated with a negative HBeAg serostatus

OBJECTIVES

Hepatitis B virus (HBV) infection is a global health burden. In this regard, Egypt has an intermediate HBV seroprevalence. HBV is classified into ten different genotypes (A-J) with different geographic distributions. Genotype D is the most prevalent in the Middle East. Limited data are available about HBV genotyping among Egyptian blood donors, particularly in Upper Egypt. We examined the seroprevalence of HBV among 12,000 blood donors attending the blood transfusion services center in Minia Governorate, Upper Egypt.

METHODS

HBsAg and HBeAg were examined by ELISA while HBV-DNA was examined by PCR. HBV genotyping was conducted by restriction fragment length polymorphism.

RESULTS

HBsAg was detected in 237 donors (1.98%). The HBV-DNA of 50 donors with the highest HBsAg OD was examined for the HBV genotype. All 50 DNA-positive samples were of genotype D. 82% of the DNA-positive donors were males, coinciding with their representation in the cohort. ALT levels were normal in 88% of genotyped subjects, while 84% of them were HBeAg negative.

CONCLUSION

Taken together, these data indicate that HBV genotype D is the predominant genotype among HBsAg-positive blood donors in Upper Egypt and was in >80% of the subjects associated with a negative HBeAg serostatus.

Prevalence of anti-HEV IgM among blood donors in Egypt

Hepatitis E virus (HEV) is a common cause of acute viral hepatitis (AVH) in developing countries. In Egypt; where up to 80% of the inhabitants of rural villages have anti-HEV antibodies denoting past infection, most of these infections are asymptomatic with little evidence that the infection causes AVH. There are accumulating reports which suggest potential risk of HEV transmission by blood transfusion. However, detection of serological markers for HEV infection or HEV RNA in Egyptian blood banks is not routinely performed. 760 blood samples from apparently healthy donors at the National blood bank were tested for markers of acute HEV infection to estimate the seroprevalence of acute HEV infection, and potential risk of infection by blood transfusion. They included 124 females (16.82%) and 636 males (83.68%), with a mean age of 23.8 +/- 5.3 years and mean ALT value of 23.3 +/- 13.2 IU/ml. Samples were tested as pools of 10 subjects. Pools with highest reactivity were retested individually to determine the frequency of positive subjects. Out of the 760 samples, three (0.45%) samples were positive for anti-HEV IgM and two of them had HEV RNA as determined by RT-PCR. In conclusion, this study suggests that the tested blood donors have low prevalence of ongoing subclinical infection with HEV and that the potential risk of transfusion may be low.

Monocytes/macrophages and natural killer cells characterize the tumor microenvironment of inflammatory breast cancer in Egyptian patients

Abstract #1054

Background: Inflammatory breast cancer (IBC) is the most aggressive form of breast cancer. IBC incidence appears to be higher in Egypt as compared to USA. Although the role of leukocytes in regulating breast cancer dissemination has been studied extensively, their role in IBC progression is not well understood. Previously, we showed that human monocytes augment the invasiveness and proteolytic activity of IBC cell lines. Aim: To compare the immunophenotype of IBC and non-IBC and to identify IBC tumor-infiltrated immune cell that may be associated with poor prognosis of IBC.
 Methods: We enrolled two groups of patients: IBC (n=13) and non-IBC (n=27) being treated at Ain Shams University hospitals. All patients underwent modified radical mastectomy. IBC patients had 7 or more metastatic axillary lymph nodes whereas non-IBC patients had 3 or less metastatic axillary lymph nodes. During surgery, blood draining from the breast tumor microenvironment, through branches of axillary vein, and peripheral blood was collected. Total mononuclear cells were isolated from collected blood and their phenotype was examined using flow cytometry. Monoclonal antibodies specific for cell surface markers for particular cells types were used: namely T-helper cells (CD3+CD4+), T-cytotoxic cells (CD3+CD4-), natural killer (NK) cells (CD56+) and monocytes/macrophages (CD14+). Results: Within each group we compared the leukocytic composition of blood collected from the tumor drainage to that of peripheral blood in IBC and non-IBC patients. 1) In IBC, we detected a significant increase in the mean percentage of NK cells and monocytes collected from the tumor site, but no significant difference in CD8+ and CD4+ cells. 2) In non-IBC, the percentage of CD4+ T cells collected from the tumor site was significantly higher than from peripheral blood. No significant differences were detected in CD8+, CD56+ and CD14+ cells.
 We compared the leukocyte composition of blood collected from both IBC and non-IBC patients. 1) In peripheral blood of IBC patients, we detected a significant increase in CD4+ T cells, but no significant differences in CD8+, CD56+ and CD14+ cells when compared to non-IBC patients. 2) When we compared the leukocyte content of blood collected from the tumor site in IBC and non-IBC, we found a significant increase in CD56+, and CD14+ cells and a significant decrease in CD4+ T cells in IBC, but no significant difference in CD8+ T cells. Conclusion: Differences in the immunophenotype of IBC versus non-IBC suggests a role for these immune cells in the metastatic dissemination and progression of IBC.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1054.

Characterization of hepatitis E-specific cell-mediated immune response using IFN-gamma ELISPOT assay

In developing countries, hepatitis E (HEV) and hepatitis A (HAV) are the major causes of acute viral hepatitis with similar feco-oral modes of transmission. In contrast to the high seroprevalence of hepatitis A infection, a low seroprevalence of HEV among children in endemic areas has been reported. These data suggest the possibility that silent HEV infection is undiagnosed by the current available methods. Many of the serological tests used for HEV diagnosis have poor specificity and are unable to differentiate among different genotypes of HEV. Moreover, the RT-PCR used for HEV isolation is only valid for a brief period during the acute stage of infection. Cell-mediated immune (CMI) responses are highly sensitive, and long lasting after sub-clinical infections as shown in HCV and HIV. Our objective was to develop a quantitative assay for cell-mediated immune (CMI) responses in HEV infection as a surrogate marker for HEV exposure in silent infection. Quantitative assessment of the CMI responses in HEV will also help us to evaluate the role of CMI in HEV morbidity. In this study, an HEV-specific interferon-gamma (IFN-gamma) ELISPOT assay was optimized to analyze HEV-specific CMI responses. We used peripheral blood mononuclear cells (PBMC) and sera from experimentally infected chimpanzees and from seroconverted and control human subjects to validate the assay. The HEV-specific IFN-gamma ELISPOT responses correlated strongly and significantly with anti-HEV ELISA positive/negative results (rho=0.73, p=0.02). Moreover, fine specificities of HEV-specific T cell responses could be identified using overlapping HEV ORF2 peptides.

Baculovirus-derived human immunodeficiency virus type 1 virus-like particles activate dendritic cells and induce ex vivo T-cell responses

We have recently developed a candidate human immunodeficiency virus type 1 (HIV-1) vaccine model based on HIV-1 Pr55(gag) virus-like particles (HIV-VLPs), produced in a baculovirus expression system and presenting a gp120 molecule from a Ugandan HIV-1 isolate of clade A (HIV-VLP(A)s). The HIV-VLP(A)s show the induction in BALB/c mice of systemic and mucosal neutralizing antibodies as well as cytotoxic T lymphocytes, by intraperitoneal as well as intranasal administration. In the present article, the effects of the baculovirus-expressed HIV-VLPs on human immature monocyte-derived dendritic cells (MDDCs) have been evaluated. The HIV-VLPs efficiently induce maturation and activation of MDDCs and are incorporated into MDDCs preferentially via an actin-dependent macropinocytosis and endocytosis. The HIV-VLP-activated MDDCs show enhanced Th1- and Th2-specific cytokine production, and the effects of HIV-VLPs on MDDCs are not mediated through Toll-like receptors 2 and 4 (TLR2 and -4) signaling. Finally, HIV-VLP-loaded MDDCs are able to induce a primary and secondary response in autologous human CD4(+) T cells in an ex vivo immunization assay. Our results on the interaction and processing of baculovirus HIV-VLPs by MDDCs give an insight into the mechanisms underlying the immune response induced by HIV-VLP(A)s in vivo.

Perforin-low memory CD8+ cells are the predominant T cells in normal humans that synthesize the beta -chemokine macrophage inflammatory protein-1beta

The synthesis of antiviral beta-chemokines has joined cytolysis as a potential mechanism for the control of HIV-1 infection by CD8(+) T cells. Recent evidence suggests that these two effector functions can diverge in some individuals infected with HIV-1; however, little is known about the CD8(+) T cell subsets in normal individuals that synthesize antiviral beta-chemokines. In this report, we have used mutliparameter flow cytometry to characterize the T cell subsets that secrete the antiviral beta-chemokine macrophage inflammatory protein (MIP)-1beta. These studies have shown: (i) CD8(+) cells are the predominant T cell subset that synthesizes MIP-1beta; (ii) MIP-1beta and IFN-gamma are synthesized congruently in most CD8(+) T cells; however, significant numbers of these cells synthesize only one of these effector molecules; (iii) approximately 60% of the CD8(+) T cells that synthesize MIP-1beta lack perforin; (iv) MIP-1beta is synthesized with approximately equal frequency by CD28(+) and CD28(-) subpopulations of CD8(+) T cells; (v) MIP-1beta is synthesized by three distinct CD8(+) T cell subsets defined by the expression of CD45R0 and CD62L; and (vi) MIP-1beta is not synthesized in short-term cultures of naive CD8(+) T cells. These results demonstrate substantial subset heterogeneity of MIP-1beta synthesis among CD8(+) T cells and suggest that these subsets should be evaluated as correlates of protective immunity against HIV-1.