Mucosal and systemic immune responses elicited by recombinant Lactococcus lactis expressing a fusion protein composed of pertussis toxin and filamentous hemagglutinin from Bordetella pertussis.

We constructed a food-grade expression system harboring a F1S1 fusion protein of Bordetella pertussis to be produced in Lactococcus lactis NZ3900 as a new oral vaccine model against whooping cough, caused by B. pertussis. F1S1 was composed of N-terminally truncated S1 subunit of pertussis toxin and type I immunodominant domain of filamentous hemagglutinin which are both known as protective immunogens against pertussis. The recombinant L. lactis was administered via oral or intranasal routes to BALB/c mice and the related specific systemic and mucosal immune responses were then evaluated. The results indicated significantly higher levels of specific IgA in the lung extracts and IgG in sera of mucosally-immunized mice, compared to their controls. It was revealed that higher levels of IgG2a, compared to IgG1, were produced in all mucosally-immunized mice. Moreover, immunized mice developed Th1 responses with high levels of IFN-γ production by the spleen cells. These findings provide evidence for L. lactis to be used as a suitable vehicle for expression and delivery of F1S1 fusion protein to mucosa and induction of appropriate systemic and mucosal immune responses against pertussis.

The effect of progesterone and 17-ß estradiol on membrane-bound HLA-G in adipose derived stem cells.

Membrane-bound HLA-G (mHLA-G) discovery on adipose derived stem cells (ADSCs) as a tolerogenic and immunosuppressive molecule was very important. Many documents have shown that HLA-G expression can be controlled via some hormones such as progesterone (P4) and estradiol (E2). Therefore, this study was designed to evaluate progesterone and estradiol effects on mHLA-G in ADSCs at restricted and combination concentrations. Three independent cell lines were cultured in complete free phenol red DMEM and subcultured to achieve suffi cient cells. These cells were treated with P4, E2 and P4 plus E2 at physiologic and pregnancy concentrations for 3 days in cell culture conditions. The HLA-G positive ADSCs was measured via monoclonal anti HLA-G-FITC/MEMG-09 by means of flow cytometry in nine groups. Data were analyzed by one way ANOVA and Tukey's post hoc tests. There were no signifi cant values of the mean percentage of HLA-G positive cells in E2-treated and the combination of P4 plus E2-treated ADSCs compared to control cells (p value>0.05) but P4 had a signifi cant increase on mHLA-G in ADSCs (p value<0.05). High P4 concentration increased mHLA-G but E2 and the combination of P4 plus E2 could not change mHLA-G on ADSCs.

Integrative Bioinformatics Analysis of The Cell Division Cycle and Ribosomal Pathways in The Rat Varicocele: Implications for Drug Discovery.

OBJECTIVE: Varicocele is a common cause of male infertility, affecting a substantial proportion of infertile men. Recent studies have employed transcriptomic analysis to identify candidate genes that may be implicated in the pathogenesis of this condition. Accordingly, this study sought to leverage rat gene expression profiling, along with protein-protein interaction networks, to identify key regulatory genes, related pathways, and potentially effective drugs for the treatment of varicocele. MATERIALS AND METHODS: In this in-silico study, differentially expressed genes (DEGs) from the testicular tissue of 3 rats were screened using the edgeR package in R software and the results were compared to 3 rats in the control group. Data was obtained from GSE139447. Setting a -11 and P<0.05 as cutoff points for statistical significance, up and down-regulated genes were identified. Based on Cytoscape plugins, protein-protein interaction (PPI) networks were drawn, and hub genes were highlighted. ShinyGO was used for pathway enrichment. Finally, effective drugs were identified from the drug database. RESULTS: Among the 1277 DEGs in this study, 677 genes were up-regulated while 600 genes were down-regulated in rats with varicocele compared to the control group. Using protein-protein interaction networks, we identified the top five up-regulated genes and the top five down-regulated genes. Enrichment analysis showed that the up-regulated genes were associated with the cell division cycle pathway, while the down-regulated genes were linked to the ribosome pathway. Notably, our findings suggested that dexamethasone may be a promising therapeutic option for individuals with varicocele. CONCLUSION: The current investigation indicates that in varicocele the cell division cycle pathway is up-regulated while the ribosome pathway is down-regulated compared to controls. Based on these findings, dexamethasone could be considered a future candidate drug for the treatment of individuals with varicocele.

Evaluation of Fas positive sperm and complement mediated lysis in subfertile individuals.

PURPOSE: Evaluation of Fas receptor on surface of sperm, as an apoptotic marker, using flow cytometry and confirming the results using an antibody-antigen complex through the classic complement pathway. MATERIALS AND METHODS: Semen samples were obtained from 10 fertile and 73 infertile individuals with diagnoses of male factor infertility. Expressions of Fas receptor and phosphatidyl serine on sperm were assessed by flow cytometry. Fas expression was further assessed by antibody-antigen complex through the complement pathway. Lysis was detected via PI (propidium iodide) staining. RESULTS: The mean Fas expression was considerably lower than previously reported values. No significant differences in the percentage of PI were detected before and after activation of the classic complement pathway. Annexin V positive samples showed low Fas expression. CONCLUSION: Our results have confirmed the presence of selected apoptotic markers such as Fas or phosphatidyl serine on ejaculate sperm, but suggest that Fas expression is low. Further studies are required to investigate the "abortive apoptosis" mechanism through Fas/Fas L.

Subcutaneous Immunization with Recombinant Lactococcus lactis Expressing F1S1 Fusion Protein Induces Systemic and Mucosal Immune Responses in BALB/C Mice.

BACKGROUND: Lactic acid bacteria such as Lactococcus (L.) lactis are powerful tools that can function as live delivery vectors and heterologous protein expression hosts in development of novel vaccines. Pertussis toxin (PT) and filamentous hemagglutinin (FHA) are important virulence factors of Bordetella (B.) pertussis and constitute the major components of commercially available acellular pertussis (aP) vaccines. The purpose of the present study was to express F1S1 fusion protein, consisted of the N-terminal region of S1 subunit from PT and FHA type 1 immunodominant domain by L. lactis and to evaluate its immunogenicity. METHODS: The fusion gene composed of sequences encoding the F1S1 and the signal peptide of usp45 fragments (SECF1S1) was codon optimized for protein production in L. lactis and was synthesized and inserted in-frame inside pNZ8149 plasmid. The resulting pNZ8149-SECF1S1 construct was introduced by electroporation into L. lactis cells (LL-F1S1). BALB/c mice were subcutaneously immunized with LL-F1S1 or commercial DTaP vaccine. The immune responses were investigated. RESULTS: The LL-F1S1-immunized mice produced significant levels of specific IFN-g compared to their respective controls and DTaP-immunized mice. The F1S1- specific IgG antibody response was lower in LL-F1S1-immunized mice while the IgG2a/IgG1 ratio was higher in this group compared to the DTaP-immunized mice. Moreover, anti-F1S1 IgA antibodies were only detected in the lung homogenates of the LL-F1S1-immunized mice, suggesting the induction of a mucosal immune response. CONCLUSION: These results indicate the feasibility of expression of F1S1 fusion protein in L. lactis. This recombinant bacterium could induce mucosal and Th1-type systemic immune responses following subcutaneous administration.

Subcutaneous administration of a fusion protein composed of pertussis toxin and filamentous hemagglutinin from Bordetella pertussis induces mucosal and systemic immune responses.

OBJECTIVES: After decades of containment, pertussis disease, caused by Bordetella pertussis seems to be re-emerging and still remains a major cause of reported vaccine-preventable deaths worldwide. The current licensed whole-cell vaccines display reactogenicity while acellular vaccines are expensive and do not induce Th1-type immune responses that are required for optimum protection against the disease. Thus, there is an urgent need to develop new vaccines and the recombinant technology seems to be the method of choice for this purpose. The present study was an attempt to develop a new, simplified, cost-effective and well-defined vaccine against Bordetella pertussis, with capacity to induce a Th1 response. MATERIALS AND METHODS: A fusion DNA fragment encoding the N-terminal region of pertussis toxin S1 subunit and filamentous hemagglutinin type 1 immunodominant domain was constructed and the corresponding fusion protein (F1S1) was produced in Escherichia coli. F1S1 in conjunction with imiquimod was administered by subcutaneous (SC) and intranasal (IN) routes to BALB/c mice. RESULTS: This vaccine formulation could elicit high levels of IFN-γ, serum IgG (with higher IgG2a/IgG1 ratio) and lung IgA after the SC and, to a lesser extent, following the IN administration. CONCLUSION: Our results indicate that the above-mentioned important proteins of B. pertussis could be successfully produced in E. coli as a single fusion protein. Furthermore, this protein could induce proper systemic and mucosal immune responses after administration via SC or IN routes.

Indoleamine 2,3-Dioxygenase Is Dispensable for The Immunomodulatory Function of Stem Cells from Human Exfoliated Deciduous Teeth.

OBJECTIVE: In this study, we sought to better understand the immunoregulatory function of stem cells derived from human exfoliated deciduous teeth (SHED). We studied the role of the interferon gamma (IFN-γ)-indoleamine 2,3-dioxygenase (IDO)-axis in immunoregulation of SHED compared to bone marrow derived mesenchymal stem cells (BMMSCs) under the same conditions. MATERIALS AND METHODS: In this cross-sectional study, recently isolated human T cells were stimulated either by mitogen or inactivated allogeneic peripheral blood mononuclear cells (PBMCs). These T cells were subsequently co-cultured with, either SHED or BMMSCs in the presence or absence of 1-methyl-tryptophan (1-MT) or neutralizing anti- human-IFN-γ antibodies. In all co-cultures we evaluated lymphocyte activation as well as IDO activity. RESULTS: SHED, similar to conventional BMMSCs, had anti-proliferative effects on stimulated T cells and reduced their cytokine production. This property of SHED and BMMSCs was changed by IFN-γ neutralization. We detected IDO in the immunosuppressive supernatant of all co-cultures. Removal of IDO decreased the immunosuppression of BMMSCs. CONCLUSION: SHED, like BMMSCs, produced the IDO enzyme. Although IFN-γ is one of inducer of IDO production in SHED, these cells were not affected by IFN-γ in the same manner as BMMSCs. Unlike BMMSCs, the IDO enzyme did not contribute to their immunosuppression and might have other cell-type specific roles.

An investigation into the association between HLA-G 14 bp insertion/deletion polymorphism and multiple sclerosis susceptibility.

Human Leukocyte Antigen G (HLA-G) gene polymorphism and expression rate have recently been suggested to have a potential role in susceptibility to Multiple Sclerosis (MS), a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system with unknown etiology. The aim of this study was to investigate the association of the frequency of HLA-G gene 14 bp insertion/deletion polymorphism and its plasma level with MS susceptibility. In this study, the HLA-G gene from 212 patients and 210 healthy individuals was amplified using real time PCR and screened for the 14 bp insertion/deletion polymorphism. In addition, HLA-G plasma levels of the patients were measured and compared to normal controls by ELISA method. Our results revealed that 14 bp insertion in HLA-G could result in lower plasma HLA-G level of the subjects, regardless of their health status and vice versa. Additionally, significant correlation of HLA-G genotype and its plasma level with MS susceptibility was observed. In conclusion, not only HLA-G 14 bp insertion/deletion polymorphism could be associated with expression rate of the HLA-G gene and its plasma level, but also could be considered as a risk factor for susceptibility to MS in our study population.

Tumor necrosis factor-α inhibits effects of aryl hydrocarbon receptor ligands on cell death in human lymphocytes.

BACKGROUND: Activation of aryl hydrocarbon receptor (AhR) leads to diverse outcome in various kinds of cells. AhR activation may induce apoptosis or prevent of apoptosis and cell death. Recent studies suggest that apoptosis effects of AhR can be modulated by inflammatory cytokine like tumor necrosis factor alpha (TNF-α). In this study, we try to investigate the possible interaction of TNF-α with the 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD), a ligand of AhR, on peripheral lymphocytes. MATERIALS AND METHODS: Human peripheral blood mononuclear cells (PBMCs) were isolated from peripheral blood by discontinuous density gradient centrifugation on ficoll. Isolated PBMCs were divided into four groups: Control group, TNF-α administered group, TCDD administered group, co-administered group with TCDD and TNF-α. Cells were maintained for a week in lymphocyte culture condition. Then, TNF-α was added to group 2 and 4. Finally, apoptosis and necrosis were analyzed in all samples using flowcytometry. RESULT: In group 4, the mean percent of necrosis and apoptosis in TCDD treatment groups was significantly larger than other groups; (P < 0.05). Furthermore, there was no significant difference between the mean percent of cell death in TNF-α administered group and TCDD administered group (P > 0.05). However, the mean percent of cell death in co-administered group with TCDD and TNF-α was significantly lower than other groups; (P < 0.05). CONCLUSION: TNF-α could significantly inhibit effects of TCDD on lymphocytes apoptosis. Combination effects of TNF-α and TCDD on lymphocyte increase cell survival.

2,3,7,8-tetrachlorodibenzo-p-dioxin decrease expression of aryl hydrocarbon receptor in peripheral lymphocyte of ß-thalassemia major patients.

BACKGROUND: ß-thalassemia major is a hereditary disease with inefficient erythropoiesis. Level of inflammatory cytokine is elevated in these patients. In this study, we investigate the effect of aryl hydrocarbon receptor (AhR) ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), on the expression of inflammatory mediators in ß-thalassemia major patient's lymphocytes. MATERIALS AND METHODS: Peripheral blood mononuclear cells of patients and healthy participants was isolated and cultured in favor of lymphocytes increment. Based on the treatment, we divided the cell into four groups. The orders of group's treatments were no treatment, tumor necrosis factor-α (TNF-α) treatment, TNF-α and TCDD treatment, TCDD treatment in Group 1-4, respectively. After cell culture, we extracted the cells RNA and converted them to cDNA. Real-time polymerase chain reaction was performed to assessment relative expression of caspase-1, NLRP3, and AhR. We compared all patient groups with equal healthy (control) groups. RESULTS: Results showed that expression of caspase-1 in patients (Groups 1 and 2) was significantly lower than healthy individuals (P < 0.05). Although, no significant difference was found (Groups 1, 2, and control) in AhR gene expression (P > 0.05). Expression of AhR in other groups of patients (3 and 4) was significantly lower than control groups (P < 0.05). Expression of caspase-1 in Group 4 was significantly larger than the control group (P < 0.001). CONCLUSIONS: We show here that chronic inflammation decrease caspase-1 expression and exposure of human lymphocytes to TCDD promote caspase-1 expression. Furthermore, activation of AhR with TCDD decreases AhR expression in lymphocytes of ß-thalassemia major disease.

Production of IFN-γ and IL-4 Against Intact Catalase and Constructed Catalase Epitopes of Helicobacter pylori From T-Cells.

BACKGROUND: Helicobacter pylori infection is highly prevalent in the developing countries. It causes gastritis, peptic ulcer disease, and gastrocarcinoma. Treatment with drugs and antibiotics is problematic due to the following reasons: cost, resistance to antibiotics, prolonged treatment and using multiple drugs. Catalase is highly conserved among the Helicobacter species and is important to the survival of the organism. It is expressed in high amounts and is exposed to the surface of this bacterium; therefore it represents a suitable candidate vaccine antigen. OBJECTIVES: A suitable approach in H. pylori vaccinology is the administration of epitope based vaccines. Therefore the responses of T-cells (IFN-γ and IL-4 production) against the catalase of H. pylori were determined. Then the quality of the immune responses against intact catalase and three epitopes of catalase were compared. MATERIALS AND METHODS: In this study, a composition of three epitopes of the H. pylori catalase was selected based on Propred software. The effect of catalase epitopes on T-cells were assayed and immune responses identified. RESULTS: The results of IFN-γ, IL-4 production against antigens, epitopes, and recombinant catalase by T-cells were compared for better understanding of epitope efficiency. CONCLUSIONS: The current research demonstrated that epitope sequence stimulates cellular immune responses effectively. In addition, increased safety and potency as well as a reduction in time and cost were advantages of this method. Authors are going to use this sequence as a suitable vaccine candidate for further research on animal models and humans in future.

The effect of stem cell from human exfoliated deciduous teeth on T lymphocyte proliferation.

BACKGROUND: Mesenchymal stem cells (MSC), a specific type of adult tissue stem cell; have the immunosuppressive effects that make them valuable targets for regenerative medicine and treatment of many human illnesses. Hence, MSC have been the subject of numerous studies. The classical source of MSC is adult bone marrow (BM). Due to many shortcomings of harvesting MSC from BM, finding the alternative sources for MSC is an urgent. Stem cells from human exfoliated deciduous teeth (SHED) are relative new MSC populations that fulfill these criteria but their potential immunosuppressive effect has not been studied enough yet. Thus, in this work the effect of SHED on the proliferation of in vitro activated T lymphocytes were explored. MATERIALS AND METHODS: In this study, both mitogen and alloantigen activated T cells were cultured in the presence of different numbers of SHED. In some co-cultures, activated T cells were in direct contact to MSCs and in other co-cultures; they were separated from SHED by a permeable membrane. In all co-cultures, the proliferation of T cells was measured by ELISA Bromodeoxyuridine proliferation assay. RESULTS: In general, our results showed that SHED significantly suppress the proliferation of activated T cells in a dose-dependent manner. Moreover, the suppression was slightly stronger when MSCs were in physical contact to activated T cells. CONCLUSION: This study showed that SHED likewise other MSC populations can suppress the activation of T lymphocytes, which can be used instead of BM derived MSCs in many investigational and clinical applications.

CD107a Expression and IFN-γ Production as Markers for Evaluation of Cytotoxic CD3+ CD8+ T Cell Response to CMV Antigen in Women with Recurrent Spontaneous Abortion.

BACKGROUND: Some evidence has shown a relationship between primary human cytomegalovirus (CMV) infection and pregnancy loss. The impact of CMV infection reactivation during pregnancy on adverse pregnancy outcomes is not completely understood. It is proposed that altered immune response, and therefore, recurrence or reactivation of latent CMV infection may relate to recurrent spontaneous abortion (RSA); however, few data are available in this regard. To find out about any cell mediated defect and reactivation of latent CMV infection in women with RPL, cellular immunity to the virus has been evaluated by specific cytotoxic T lymphocyte (CTL) response to CMV. MATERIALS AND METHODS: In a case control study, CTL CD107a expression and in- tercellular IFN-γ production in response to CMV pp65 antigen and staphylococcus enterotoxin B (SEB) in women with RSA were assessed by flow cytometric analysis. Forty-four cases with history of recurrent pregnancy and forty-four controls with history of successful pregnancies were included. The FACSCaliber flow cytometer were used for analysis. RESULTS: No significant difference was observed between CD107a expression and IFN-γ production in response to CMV PP65 antigen in RPL patients and control group. How- ever, the cytotoxic response to SEB antigen in patients with RPL was significantly lower than control group (p=0.042). CONCLUSION: The results of this study show that impaired CD107a expression and IFN-γ production as CTL response to CMV does not appear to be a major contrib- uting and immune incompetence factor in patients with RPL, but cytotoxic T cell response defect to other antigens requires to be assessed further in these patients.

Comparing the immunoregulatory effects of stem cells from human exfoliated deciduous teeth and bone marrow-derived mesenchymal stem cells.

Stem cells from human exfoliated deciduous teeth (SHED) have been introduced recently and possess characteristics similar to mesenchymal stem cells (MSCs). Because of their convenient accessibility and safety of harvest, SHED can be a preferable source for the ever-increasing MSCs' applications  While they are new, their immunoproperties have not been adequately studied. In this study, we aimed to explore the effect of SHED on T lymphocytes and compare it to conventional MSCs (BMMSCs).At first the isolated T lymphocytes were activated specifically/nonspecifically in vitro and cocultured with SHED or BMMSCs under the same conditions, subsequently their proliferation and cytokine secretion (IL-2 and IFN-γ) were measured.In our experiment, BMMSCs and SHED inhibit the proliferation and cytokine production of both PHA and alloantigen stimulated T lymphocytes in a dose-dependent manner. In direct and indirect contact to T lymphocytes, the inhibition of BMMSCs (but not of SHED) was significantly different The cytokine production from activated T cells was affected differently by two types of MSCs. The inhibition decreased by the separation of lymphocytes and MSCs by a semipermeable membrane, but it was not abolished.This study showed that SHED suppress the activation of human T lymphocytes in vitro like other MSCs. Compared to BMMSCs, this suppression was alleviated. In the equal conditions, the pattern of immune-modulation of BMMSCs and SHED was different, suggesting that SHED do not exert the exact mechanisms of BMMSCs' immunosuppression., This finding should be verified by further studies focused on the detailed mechanisms  of the immunomodulation of SHED and also BMMSCs.

Procalcitonin: a reliable marker for the diagnosis of neonatal sepsis.

OBJECTIVES: In the last few years, serum procalcitonin has been proposed as an early marker of infections in neonates, with varying results. In this study, we aimed to investigate the value of procalcitonin, and C- reactive protein in establishing the diagnosis of neonatal sepsis. MATERIALS AND METHODS: Blood samples were collected at admission from 69 neonates with suspected infection (admitted to the Neonatal Intensive Care Units at Alzahra and Dr Beheshti Hospital in and Fatema-Zahra in Najafabad from May 2005 to April 2006). Patients were categorized in different groups according to clinical symptoms of sepsis, bacteriological and laboratory results. Group I consisted of 20 newborns with positive blood cultures and other biological tests which suggested infection. Group II consisted of 49 neonates with negative blood cultures but had two or three of clinical signs of sepsis. The control group included 18 healthy neonates with physiological hyperbilirubinemia and no clinical and biological data of infection, referred to the hospital for bilirubin determination. Procalcitonin and C-reactive protein (CRP) were determined by immunoluminometric assay and nephlometry method respectively. RESULTS: Mean levels of procalcitonin and CRP in septic neonates (group I) were significantly higher than the other two groups (P< 0.005). Sensitivity, specificity, positive predictive value and negative predictive value were determined for all markers and compared with each other. CONCLUSION: We conclude that procalcitonin is a better marker than CRP in the diagnosis of neonatal sepsis.

Phenotypic characterizations and comparison of adult dental stem cells with adipose-derived stem cells.

OBJECTIVES: Mesenchymal stem cells or "multipotent stromal cells" are heterogeneous cell population with self-renewal and multilinage differentiation. The aim of this study was to examine and compare the expression of important stem cell surface markers on two populations of mesenchymal stem cells, one derived from human exfoliated deciduous teeth and the other derived from human adipose tissue. These new stem cells will offer a promising avenue for prevention and reversal of many human diseases such as type 1 diabetes and prevention of liver fibrotic process. METHODS: Mesenchymal stem cells were isolated and cultured from human adipose tissue and dental pulp of human exfoliated deciduous teeth. The cultured cells then were harvested and stained by different fluorescent labeled monoclonal antibodies against surface markers and were analyzed using flow cytometry. RESULTS: Both different cell populations expressed CD44, CD90 and CD13 (stem cell markers) with similar intensity. They did not express hematopoietic markers (CD11b, CD19 and CD34), and lymphocyte or leukocyte antigens CD3, CD7, CD20, CD14, CD45, CCR5 (CD195), CD11b and CD10 on their surfaces. Two different cell types demonstrated different levels of expression in CD56 and CD146. Mesenchymal stem cells from human exfoliated deciduous teeth were positive for CD105 and were negative for CCR3 and CCR4 expression. CONCLUSIONS: Both cell populations derived from adipose tissue and dental pulp showed common phenotypic markers of mesenchymal stem cells. In conclusion, mesenchymal stem cells could be isolated and cultured successfully from dental pulp of human exfoliated deciduous teeth, they are very good candidates for treatment and prevention of human diseases.

Distribution of HLA-B*27 alleles in patients with ankylosing spondylitis in Iran.

BACKGROUND: HLA-B*27 is strongly associated with ankylosing spondylitis (AS). It represents a family of alleles that differ among ethnic groups. OBJECTIVE: The aim of this study was to determine the distribution of HLA-B*27 alleles in AS patients and healthy controls in Isfahan (Iran). METHODS: Sixty AS patients and 430 healthy blood donors were selected. All subjects were HLA-B*27 positive by flow cytometry. HLA-B*27 subtypes were determined by PCR-SSP. RESULTS: Forty patients (66.7%) and 17 controls (3.95%) were HLA-B*27 positive. Subtypes detected by PCR-SSP were B*2705, B*2702, B*2704 and B*2707. One patient was B*2702/B*2710. No significant difference was found in the distribution of these alleles between AS patients and controls. CONCLUSION: Although Caucasian subtypes are predominant among Iranians, this population is characterized by a combination of both specific Caucasian and Oriental subtypes. However such results should be interpreted carefully because of the small sample size in our investigation and definitive conclusion awaits more ethnic-group studies.

Evaluation of CD11b expression on peripheral blood neutrophils for early detection of neonatal sepsis.

Neonatal sepsis is a disease of infants who are less than 1 month of age. These infants are clinically ill, and their blood culture are positive for bacteria. The reported incidence of neonatal sepsis for all infants is 1 to 10 per 1000 live births. The mortality rate is 4.2-26%. The clinical signs are not specific and diagnosis of neonatal sepsis is one of the most difficult tasks in clinical medicine. The aim of this work was determination of CD11b sensitivity and specificity for early detection of neonatal sepsis. We studied 65 neonates with gestational age of 27 to 38 weeks who were suspected for sepsis within the 28 days of life. Whole blood was obtained from neonates to determine CD11b expression on peripheral blood neutrophils by flow cytometry. C-Reactive protein (CRP) was measured qualitatively. Neonates were divided into two groups. Classification was based on the result of the blood culture. In the sepsis group all of the neonates (n=8) showed positive blood culture and clinical symptoms. In the suspected group (n=57) the neonates showed clinical signs but blood cultures were negative. Sensitivity and specificity of CD11b were 75%, 100% respectively. Also positive and negative predictive values of CD11b were 100% and 86% respectively. Results of present study and previous studies showed that measurement of neutrophil surface markers can be useful for diagnosis of infection in the early phases. Also, the quantitative measurement of CRP in addition to CD11b further enhances the ability to diagnose infections and improves sensitivity and negative predictive value by 100%.

Leukemia markers expression of peripheral blood vs bone marrow blasts using flow cytometry.

BACKGROUND: Flow cytometric techniques are widely used in clinical hematology. Characterization of leukemias by immunotyping is particularly helpful when the morphology is difficult to interpret. The major advantage of using immune markers by flow cytometry is the identification of particular leukemia subtype, not recognized by morphologic criteria, which may have prognostic significance. Current literature suggests when peripheral blood (PB) is consisted of 30% blasts or higher diagnosis of acute leukemia is most likely. However, bone marrow aspiration may also be performed as a confirmatory diagnosis. Immunotyping of PB and BM in leukemias not only determine the decision making for a specific therapeutic regimen, but also is a practical prognostic indicator. MATERIAL/METHODS: We evaluated 18 patients with acute myeloid Leukemia (AML) and 13 patients with acute lymphoid leukemia (ALL). In all cases, the amount of blasts in PB was 30% or higher. Two ml PB and BM samples from each patient was collected. Following the preparation process, expression of markers was detected by using flow cytometry. The panel of monoclonal antibodies used in this study were consisted of CD3, CD7, CD5 (for T lymphocytes lineage); CD19, CD22, CD20, CD10 (for B lymphocytes lineage); CD13, CD14, CD33 (for myeloid subsets); and TDT, HLA-DR, CD45 (non lineage restricted). Expression levels of PB and BM markers were compared by using statistical analysis. RESULTS: The results showed apparent discrepancies for some markers in ALL group. However, in AML patients most of the selected markers have shown considerable correlation between PB and BM samples. Only four markers (CD13, CD14, CD45, and HLA-DR) showed positive correlation. In contrast, most markers (CD3, CD5, CD13, CD14, CD19, CD45, HLA-DR, and TdT) showed strong correlation between PB and BM samples in AML group. CONCLUSIONS: The findings of this study suggests that targeted gating strategy for blast population as well as selection of a suitable panel of monoclonal antibodies may be essential for diagnosis of leukemia resulting in similar immunotyping pattern in PB and BM. Although our results are preliminary, this can minimize the necessity of BM aspiration for leukemia patients.