The impact of pre-donation viral markers screening of new blood donors on blood safety

BACKGROUND

The risk of transfusion-transmissible infections (TTIs) remains a concern in transfusion medicine. Since the rate of infection among first-time blood donors is higher than repeated donors, strategies to enhance blood safety can focus on new donors. The aim of the study was to investigate the effect of pre-donation viral screening of new donors on blood safety.

METHODS AND MATERIALS

The pre-donation screening of new donors was implemented in the Kurdistan blood center. In this program, new donors who met the blood donation criteria were informed about the program and only a blood sample was donated for HBs Ag, HCV Ab, and HIV Ab testing. New donors with negative results were invited to donate blood after 12 weeks. A unit of blood was collected from eligible returned donors. Laboratory tests were performed again using the same methods. Finally, the prevalence of confirmed positive TTI results among donated blood in Kurdistan blood center was compared before and after the establishment of program.

RESULTS

During the study, 4,434 new donors were screened for viral markers. A total of 41 new donors (0.92%, 95% CI, 0.007-0.13) had repeatedly reactive results and infection was confirmed in blood sample of 24 donors (0.54%, 95% CI, 0.003-0.008). Overall, 56% of new donors returned for blood donation. Prevalence of confirmed TTIs markers in collected blood units was 0.27% and 0 before and after implementing program, respectively.

CONCLUSIONS

This study indicated that Pre-donation screening can reduce the risk of TTI transmission by identifying infected donors at the pre-donation phase.

Induction of Systemic Lupus Erythematosus-like Syndrome in BALB/c Mice Leads to Disturbance in Splenic T Cell Subpopulations

Mechanisms underlying the systemic lupus erythematosus (SLE) have not yet been elucidated. In this study, we evaluated the balance of T cell subsets in BALB/c mice model of SLE induced; using Con A and polyamines as DNA immunogenicity modifiers. BALB/c mice were immunized subcutaneously with 50 µg extracted DNA from cells cultured in different conditions: splenocytes+ polyamines (group P), splenocytes+ Con A (group A), splenocytes+ polyamines+ Con A (group PA) and splenocytes only (control). Anti-double-stranded DNA -(ds-DNA) antibodies, proteinuria, and antinuclear autoantibodies were assessed by enzyme-linked immunosorbent assay, Bradford method, and immunofluorescence respectively. Transcription factors of different T helper subsets were examined by real-time polymerase chain reaction. The serum level of the anti-dsDNA antibody in group PA was higher than that in the other groups (p>0.05). Antinuclear antibody (ANA) titer increased in groups A and PA. Proteinuria level in group PA was significantly higher than that in the control group (p<0.001). Expression of Foxp3 was decreased in group A (p=0.001). Additionally, the ratios of T-bet/GATA3 and T-bet/Foxp3 were also increased in group A. (p>0.05). Our results revealed an increased ratio of Th1 to Th2 and decreased expression of Foxp3 in group A, but group PA manifested more obvious signs of the disease. These results suggest that other mechanisms rather than disturbance in T cells' balance may involve the development of disease symptoms.

Effect of MicroRNA-21 Transfection on In-vitro Differentiation of Human Naive CD4+ T Cells to Regulatory T Cells

Regulatory T cells (Tregs) are important components of the immune system that modulate responses of other cells. These cells are involved in peripheral tolerance mechanisms, so defect in development and function of these cells can result in autoimmune disease. Increasing evidence supports the role of microRNAs-21 (miR-21) in the regulation of forkhead box P3 (Foxp3) expression in Tregs. We aimed to determine whether miR-21 transfection to naive CD4+ T cells can be useful in generation of iTregs in-vitro. We investigated in-vitro differentiation of miR-21-transfected naive CD4+ T cells to iTregs and compared these iTregs to cytokine-differentiated iTregs and control group. We showed that expression of Foxp3, transforming growth factor beta (TGF-β), and interleukin-10 (IL-10) are increased in iTregs generated after miR-21 transfection in comparison with cytokine-differentiated iTregs and control group. Our findings demonstrate that miR-21 has positive role in in-vitro generation of induced regulatory T-cells (iTregs).

Evaluation of TLR9 expression on PBMCs and CpG ODN-TLR9 ligation on IFN-α production in SLE patients

CONTEXT

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by autoreactive antibodies. Recent findings revealed the importance of innate immune responses, especially Toll-like receptors (TLRs) in the pathogenesis of SLE.

OBJECTIVE

In this study, the level of TLR9 expression on peripheral blood mononuclear cells (PBMCs) was analyzed. The levels of produced IFN-α were also measured in supernatant of PBMCs from SLE patients and healthy controls after stimulation with CpG ODN2216 which is a plasmocytoid dendritic cell (pDC)-specific TLR9 ligand.

MATERIALS AND METHODS

TLR9 expression was analyzed by real-time polymerase chain reaction (PCR) and flow cytometry in 35 SLE patients and 38 healthy controls and IFN-α concentration was measured in supernatants using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The results showed that the TLR9 expression in the mRNA and the protein level was significantly higher in PBMCs from SLE patients. However, IFN-α concentration in patients and controls significantly increased in response to CpG stimulation but this increase was significantly higher in healthy controls compared with SLE patients. Our results do not show any association between taking hydroxychloroquine and reduction in IFN-α production in SLE patients.

DISCUSSION AND CONCLUSIONS

Regarding the findings of the study, there is the possibility that TLR9 has played a role in SLE pathogenesis, and consequently it implies that TLRs can be considered to be the therapeutic targets for systemic autoimmunity. We may conclude that PBMCs in patients are functionally impaired in response to TLR ligation via innate response stimulating pathogen-associated molecular patterns (PAMPs).

Evaluation of PBMC Distribution and TLR9 Expression in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease which results in damage to various organs. Some animal studies have revealed that activation of Toll-like receptors (TLRs) is important in the pathogenesis of SLE. In the present study, the percentage of different immune cell subsets in 35 SLE patients and 38 control subjects was analyzed by flow cytometry. We also assessed the expression of TLR9 in the population of peripheral blood mononuclear cells (PBMCs) including T lymphocytes (CD4+ and CD8+), B lymphocytes (CD19+), NK cells (CD56+) and monocytes (CD14+) in SLE patients and healthy controls. The results showed that the percentage of CD8+ T lymphocytes and CD14+ monocytes were significantly higher (p˂0.001) in the SLE patients than the healthy control subjects. Moreover, the percentage of CD56+ NK cells were significantly lower in the SLE patients than the healthy control subjects (p=0.001). The findings indicated that the expression of TLR9 was significantly higher in CD4+ and CD8+ T lymphocytes and CD19+ B lymphocytes of SLE patients than in control subjects (all p˂0.05). The difference in TLR9 expression are involved in pathogenesis of the SLE, hence it can be used as an indicator for SLE diagnosis.

Different Doses of Transforming growth factor-β on In vitro Differentiation of Human Naïve CD4+ T Cells to T Helper 17

An appropriate differentiation of distinct human CD4+ T cell subset is critical for manipulating these cells for using in immunity related diseases. Despite various attempts to clarify the role of different factors involved in Th17 differentiation, many crucial contradictions yet remained to be optimized. Although it has been shown that the differentiation of in-vitro Th17 cells culture conditions requires the presence of IL-1beta, IL-23, IL-2, IL-21, IL-6 and TGF-β, the optimum amount of TGF-β regulating in vitro human Th17 cell differentiation is still unclear. In the current study, a flow cytometric assay was used to evaluate the effect of different concentrations of TGF-β and a combination of IL-1beta, IL-23, IL-2 without using IL-6 on development of Interleukin (IL)-17-producing T helper (Th17) cells. According to our findings, 0.1 ng/ml of TGF-β significantly increases the expression of IL-17 in comparison to other concentrations of this cytokine. Results indicated the vital role of TGF-β cytokine in the polarization of human Th17 cells in vitro.

The role of interleukin-23 in stability of in vitro T helper-17 cells

Interleukin (IL)-17-producing T helper (Th)-17 cells have recently been explained as a distinct population of CD4+ T cells which play an important role in immunity against infectious agents. Establishment of persistent phenotype of Th17 cells and recognition of lineage-deviating factors are of most attractive goals in modern researches in immunology. Although IL-6 and TGF-β are frequently used to differentiate naive T cells to Th17 phenotype in mouse models, the application of IL-23 and its importance in preventing cells from plasticity needs to be more investigated. Our main objective was to evaluate the role of IL-23 in Th17 to Th1 plasticity. In this research project, we generated in vitro Myelin oligodendrocyte glycoprotein (MOG)-specific Th17 cells in the presence of TGF-β, IL-6, IL-23 and peptide MOG35-55. Th17 development was confirmed by assessment of relevant transcription factors and secreted cytokines by flowcytometry and ELISA, respectively. Th17 to Th1 plasticity was monitored by consecutive samplings in different time points without any extra supplementation of IL-23. Cell culture supernatant was evaluated for Interferon (IFN)-γ secretion and cells were evaluated for intracellular expression of this cytokine. Our results showed that the employed method was relatively convenient in developing antigen-specific Th17 cells. We also showed that IL-23 deprivation which happens by prolongation of culture period, can convert IL-17 producing cells to IFN-γ secreting Th1 phenotype. IL-23 can be considered as a Th17 phenotype stabilizing factor for in-vitro developed lineages.

What do we need to eradicate rubella in the Islamic Republic of Iran?

To evaluate the need for congenital rubella syndrome prevention in our national health programme we aimed to determine the rate of anti-rubella positivity in umbilical cord blood samples 8 years after measles-rubella mass vaccination in the Islamic Republic of Iran. In a cross-sectional study we tested umbilical cord blood samples for anti-rubella IgG and IgM by ELISA in 154 deliveries at a university hospital in Tehran. Overall 72.7% of umbilical cord blood samples were positive for anti-rubella lgG and 27.3% were negative. All of the samples were negative for anti-rubella IgM. In the samples with a history of mothers' rubella vaccination, only 87.5% were positive for anti-rubella IgG. The results suggest the need for another mass vaccination for rubella in women of child-bearing age and continuation of routine vaccination of infants, plus consideration of obligatory anti-rubella IgG testing before pregnancy in women who were not vaccinated and vaccination of women before marriage.