The effects of iron injection on blood doping biomarkers in dried blood spots.

Iron supplementation is not considered as a doping method; however, it can affect the levels of several biomarkers of the hematologic module of the athlete biological passport (ABP), such as the reticulocyte percentage (%RET) and hemoglobin (HGB) level. Thus, iron injection could be a confounding factor in antidoping analyses. Previous studies have suggested that the HGB level and the expression levels of reticulocyte-related-mRNAs, such as 5'-aminolevulinate synthase 2 (ALAS2) and carbonic anhydrase 1 (CA1), could be promising biomarkers for the ABP and detectable in dried blood spots (DBSs). Therefore, in this study, we examined the impact of iron injection on the levels of these potential biomarkers in DBSs. Reticulocyte-related-mRNAs analyses were performed by RT-qPCR. Ferritin level in DBS was measured with enzyme-linked immunosorbent assay (ELISA) method. Notably, there were no significant effects of iron supplementation on the levels of ALAS2 and CA1 mRNAs but by contrast, the %RET and immature reticulocyte fraction (IRF) measured in whole blood increased significantly following iron injection. As expected, iron supplementation increased the ferritin level significantly in both serum and DBS samples. In conclusion, these findings reinforce the specificity of reticulocyte-related mRNAs in DBSs as biomarkers of blood doping to target in antidoping analyses.

Efficacy and safety of a low monthly dose of intravenous iron sucrose in peritoneal dialysis patients.

PURPOSE: Scientific data regarding intravenous iron supplementation in peritoneal dialysis (PD) patients are scarce. In attempting to administer the minimum monthly IV iron dose that could improve erythropoiesis, we wanted to assess the safety and efficacy of monthly maintenance intravenous administration of 100 mg iron sucrose in PD patients. METHODS: In a 9-month prospective study, all clinically stable PD patients received intravenously 200 mg of iron sucrose as a loading dose, followed by monthly doses of 100 mg for five consecutive months. Levels of hemoglobin (Hb), ferritin, transferrin saturation (TSAT), reticulocyte hemoglobin content (CHr) and C-reactive protein (CRP) were measured before each administration and 3 months after the last iron infusion. Also, doses of concurrent erythropoietin administration were recorded. RESULTS: Eighteen patients were eligible for the study. Mean levels of Hb and ferritin increased significantly (from 10.0 to 10.9 mg/dL, p = 0.01 and from 143 to 260 ng/mL, p = 0.005), as well as the increase in TSAT levels approached borderline significance (from 26.2 to 33.1%, p = 0.07). During the 6 months of iron administration, the erythropoietin dose was reduced in five patients and discontinued in one. During the 3 months following the last iron infusion, three of them again raised the erythropoietin dose to previous levels. None of the patients experienced any side effects related to IV iron administration. CONCLUSIONS: A monthly maintenance intravenous dose of 100 mg iron sucrose may be a practical, effective, and safe in the short term, treatment of anemia in PD patients resulting in improved hemoglobin levels, iron indices, and erythropoietin response.

The Role of Reticulocyte Hemoglobin Content for Diagnosis of Iron Deficiency and Iron Deficiency Anemia, and Monitoring of Iron Therapy: a Literature Review.

BACKGROUND: The diagnosis of iron deficiency anemia is still complicated and most of the tests have drawbacks. Bone marrow examination, the gold standard for the diagnosis of iron deficiency and iron deficiency anemia, is a painful, invasive, and costly procedure. Other methods are also used to diagnose iron deficiency and iron deficiency anemia; soluble transferrin receptor, serum iron, serum ferritin, and transferrin saturation are most common biomarkers of iron status that are frequently affected by inflammation, chronic diseases, and in the normal aging process (except soluble transferrin receptor). All are less available compared to complete blood count with reticulocyte hemoglobin content (CHr). Reticulocytes have a normal life span of one or two days in the circulation. CHr is a good indication of iron availability and an early marker of iron deficient erythropoiesis which can be obtained readily using automated blood cell analyzers. Therefore, the main objective of the current review is to assess the role of CHr for diagnosis of iron deficiency, iron deficiency anemia, and monitoring of iron therapy. METHODS: Studies published in English were searched using the National Library of Medicine, PubMed, and Google scholar databases. RESULTS: According to this review, CHr has a moderate sensitivity and specificity for diagnosing iron deficiency, and is less affected by inflammation than serum iron, transferrin saturation, and ferritin and is an early predictor of treatment response. It is used in screening of iron deficiency, diagnosis of iron deficiency anemia, and diagnosis of functional iron deficiency anemia in acute or chronic diseases or inflammation. CHr is also important in treatment monitoring. It is useful for early measurement of response to iron therapy, increasing within days of the initiation of iron therapy. It helps monitoring of intravenous iron supplementation, recombinant human erythropoie¬tin therapy, and oral iron therapy in hemodialysis and non-hemodialysis patients, and children. CONCLUSIONS: It is easy to analyze, less time consuming, and less expensive than bone iron examination and iron biochemical tests. However, there is no standardized cutoff point and different researchers use varying cutoff values which affects its accuracy in diagnosing iron deficiency and it should therefore be standardized. Moreover, since CHr can be affected with any conditions that cause iron restricted erythropoiesis, further analysis may be needed.

Oral administration of the LSD1 inhibitor ORY-3001 increases fetal hemoglobin in sickle cell mice and baboons.

Increased levels of fetal hemoglobin (HbF) lessen the severity of symptoms and increase the life span of patients with sickle cell disease (SCD). More effective strategies to increase HbF are needed because the current standard of care, hydroxyurea, is not effective in a significant proportion of patients. Treatment of the millions of patients projected worldwide would best be accomplished with an orally administered drug therapy that increased HbF. LSD1 is a component of corepressor complexes that repress γ-globin gene expression and are a therapeutic target for HbF reactivation. We have shown that subcutaneous administration of RN-1, a pharmacological LSD1 inhibitor, increased γ-globin expression in SCD mice and baboons, which are widely acknowledged as the best animal model in which to test the activity of HbF-inducing drugs. The objective of this investigation was to test the effect of oral administration of a new LSD1 inhibitor, ORY-3001. Oral administration of ORY-3001 to SCD mice (n = 3 groups) increased γ-globin expression, Fetal Hemoglobin (HbF)-containing (F) cells, and F reticulocytes (retics). In normal baboons (n = 7 experiments) treated with ORY-3001, increased F retics, γ-globin chain synthesis, and γ-globin mRNA were observed. Experiments in anemic baboons (n = 2) showed that ORY-3001 increased F retics (PA8695, predose = 24%, postdose = 66.8%; PA8698: predose = 13%, postdose = 93.6%), γ-globin chain synthesis (PA8695: predose = 0.07 γ/γ+ß, postdose = 0.20 γ/γ+ß; PA8698: predose = 0.02 γ/γ+ß, postdose = 0.44 γ/γ+ß), and γ-globin mRNA (PA8695: predose = 0.06 γ/γ+ß, postdose = 0.18 γ/γ+ß; PA8698: predose = 0.03 γ/γ+ß, postdose = 0.33 γ/γ+ß). We conclude that oral administration of ORY-3001 increases F retics, γ-globin chain synthesis, and γ-globin mRNA in baboons and SCD mice, supporting further efforts toward the development of this drug for SCD therapy.

Applying newer parameter Ret-He (reticulocyte haemoglobin equivalent) to assess latent iron deficiency (LID) in blood donors-study at a tertiary care hospital in India.

BACKGROUND: It is important to detect Latent Iron Deficiency (LID) to prevent development of an overt iron deficiency anemia. Early detection is difficult by using conventional hematological and biochemical parameters. Soluble transferrin receptor (sTfR) is presently the gold standard for diagnosing LID. We evaluated the utility of Reticulocyte Hemoglobin Equivalent (Ret-He), a newer hematological parameter, to predict LID in blood donors as compared to sTfR. METHODS: This was a randomized prospective study performed on 501 donor samples over a period of three-months. All donors were included after administering medical history questionnaire and a brief physical examination in accordance with national guidelines (Hb ≥12.5). Additional samples were collected during donation according to the institutional standard operating procedure (SOP). All hemograms were performed on the Sysmex XE-2100 analyzer which included Ret-He. sTfR was measured in batch assays by ELISA (Biovendor, Czech Republic). Ret He <28 pg and sTfR≥3µg/ml were used to diagnose LID. Serum Iron, Total Iron Binding Capacity (TIBC) and Serum Ferritin were also measured simultaneously. RESULTS: Of the 501 blood donors, sTfR and Ret-He detected LID in 148 and 135 donors respectively. In comparison to sTfR, Ret-He had sensitivity of 92.7%, a specificity of 97.16%, PPV of 93.1% and NPV of 96.3%. Serum Ferritin, TIBC and serum Iron had comparatively lower sensitivity of 87.16%, 79.7% and 77.7% respectively. CONCLUSION: Ret-He can be used as a routine screening test to detect LID in blood donors. This could provide an opportunity to make appropriate and timely interventions like dietary changes or drug supplementation.

Transcriptomic biomarkers of altered erythropoiesis to detect autologous blood transfusion.

Autologous blood transfusion is a powerful means of improving performance and remains one of the most challenging methods to detect. Recent investigations have identified 3 candidate reticulocytes genes whose expression was significantly influenced by blood transfusion. Using quantitative reverse transcription polymerase chain reaction as an alternative quantitative method, the present study supports that delta-aminolevulinate synthase 2 (ALAS2), carbonic anhydrase (CA1), and solute carrier family 4 member 1 (SLC4A1) genes are down-regulated post-transfusion. The expression of these genes exhibited stronger correlation with immature reticulocyte fraction than with reticulocytes percentage. Moreover, the repression of reticulocytes' gene expression was more pronounced than the diminution of immature reticulocyte fraction and reticulocyte percentage following blood transfusion. It suggests that the 3 candidate genes are reliable predictors of bone marrow's response to blood transfusion and that they represent potential biomarkers for the detection of this method prohibited in sports.

[Biological diagnosis of iron deficiency in children]. / Diagnostic biologique de la carence martiale chez l'enfant.

Measurement of serum ferritin (SF) is currently the laboratory test recommended for diagnosing iron deficiency. In the absence of an associated disease, a low SF value is an early and highly specific indicator of iron deficiency. The WHO criteria proposed to define depleted storage iron are 12µg/L for children under 5 years and 15µg/L for those over 5 years. A higher threshold of 30µg/L is used in the presence of infection or inflammation. Iron deficiency anemia, with typical low mean corpuscular volume and mean corpuscular hemoglobin, is only present at the end stage of iron deficiency. Other diagnostic tests for iron deficiency including iron parameters (low serum iron, increased total iron-binding capacity, low transferrin saturation) and erythrocyte traits (low mean corpuscular volume, increased zinc protoporphyrin) provide little additional diagnostic value over SF. In children, serum soluble transferrin receptor (sTfR) has been reported to be a sensitive indicator of iron deficiency and is relatively unaffected by inflammation. On the other hand, sTfR is directly related to extent of erythroid activity and not commonly used in clinical practice. In population surveys, approaches based on combinations of markers have been explored to improve the specificity and sensitivity of diagnostic. In addition to Hb value determination, a combination of parameters (among transferrin saturation, zinc protoporphyrin, mean corpuscular volume or serum ferritin) was generally used to assess iron deficiency. More recently sTfR/ ferritin index were evaluated, sTfR in conjunction with SF allowing to better distinguishing iron deficiency from inflammatory anemia. Also, hepcidin measurements appeared an interesting marker for diagnosing iron deficiency and identifying individuals in need of iron supplementation in populations where inflammatory or infectious diseases are frequently encountered. Reticulocyte Hb content (CHr) determination is an early parameter of iron deficiency erythropoiesis. CHr can be measured with several automated hematology analyzers and so, used for individual's iron status assessment. In addition to Hb concentration determination, individual's iron status is commonly assessed in the pediatric clinical practice by the SF measurement accompanied by the determination of C-reactive protein for detection of a simultaneous acute infection and/or inflammation.

Mitigation of whole-body gamma radiation-induced damages by Clerodendron infortunatum in mammalian organisms.

Several phytoceuticals and extracts of medicinal plants are reported to mitigate deleterious effects of ionizing radiation. The potential of hydro-alcoholic extract of Clerodendron infortunatum (CIE) for providing protection to mice exposed to gamma radiation was investigated. Oral administration of CIE bestowed a survival advantage to mice exposed to lethal doses of gamma radiation. Radiation-induced depletion of the total blood count and bone marrow cellularity were prevented by treatment with CIE. Damage to the cellular DNA (as was evident from the comet assay and the micronucleus index) was also found to be decreased upon CIE administration. Radiation-induced damages to intestinal crypt cells was also reduced by CIE. Studies on gene expression in intestinal cells revealed that there was a marked increase in the Bax/Bcl-2 ratio in mice exposed to whole-body 4 Gy gamma radiation, and that administration of CIE resulted in significant lowering of this ratio, suggestive of reduction of radiation-induced apoptosis. Also, in the intestinal tissue of irradiated animals, following CIE treatment, levels of expression of the DNA repair gene Atm were found to be elevated, and there was reduction in the expression of the inflammatory Cox-2 gene. Thus, our results suggest a beneficial use of Clerodendron infortunatum for mitigating radiation toxicity.

Use of Reticulocyte Hemoglobin Content in the Assessment of Iron Deficiency in Children With Inflammatory Bowel Disease.

BACKGROUND: Iron deficiency and anemia affect up to 50% to 75% of patients with inflammatory bowel disease (IBD). Iron deficiency in IBD may be difficult to diagnose because of the effect of inflammation on iron status biomarkers. Thus, there is a need for better methods to accurately determine iron status in IBD. OBJECTIVE: The aim of the study was to investigate the association of inflammation with hemoglobin content of reticulocytes (CHr) and the utility of CHr in comparison to standard iron biomarkers. METHODS: We conducted a cross-sectional study of children with IBD. Iron biomarkers (CHr, ferritin, soluble transferrin receptor [sTfR], hepcidin, hemoglobin) were measured along with systemic biomarkers of inflammation (C-reactive protein, α1-acid glycoprotein]. Spearman correlations were used to evaluate the relation of inflammation and iron biomarkers. The criterion standard for iron deficiency was defined as inflammation-corrected ferritin <15 µg/L or sTfR >8.3 mg/L. Receiver operating characteristic curves were used to estimate the prognostic values of all iron biomarkers to identify patients with iron deficiency. RESULTS: We analyzed data in 62 children ages 5 to 18 years. Sixty-nine percent of our subjects had Crohn disease and 31% had ulcerative colitis, of which 42% were girls and 53% African American. The prevalence of anemia was 32%, of iron deficiency was 52% using ferritin <15 µg/L or sTfR >8.3 mg/L, 39% using red blood cell distribution width of >14.5%, 26% using body iron stores of <0 mg/kg body weight, 25% using CHr of <28 pg, and 11% using mean corpuscular volume of <75 fL/cell. The prevalence of elevated CRP or AGP was 48%. After correcting ferritin and sTfR levels for inflammation, the prevalence of iron deficiency was 68%. CHr was correlated with C-reactive protein (rs -0.44, P < 0.001) and α1-acid glycoprotein (rs -0.37, P < 0.05). The optimal prognostic value for inflammation-adjusted CHr to predict iron deficiency was 34 pg (area under the receiver operating characteristic of 0.70), with 88% sensitivity and 30% specificity. CONCLUSIONS: Iron deficiency and anemia are common in this pediatric IBD cohort. All explored iron biomarkers, including CHr, were affected by inflammation and should be adjusted. A single iron biomarker is unlikely to best predict iron deficiency in pediatric IBD. Iron intervention studies are needed to examine the response of iron biomarkers to iron supplementation in the setting of inflammation.

Intravenous Iron Carboxymaltose as a Potential Therapeutic in Anemia of Inflammation.

Intravenous iron supplementation is an effective therapy in iron deficiency anemia (IDA), but controversial in anemia of inflammation (AI). Unbound iron can be used by bacteria and viruses for their replication and enhance the inflammatory response. Nowadays available high molecular weight iron complexes for intravenous iron substitution, such as ferric carboxymaltose, might be useful in AI, as these pharmaceuticals deliver low doses of free iron over a prolonged period of time. We tested the effects of intravenous iron carboxymaltose in murine AI: Wild-type mice were exposed to the heat-killed Brucella abortus (BA) model and treated with or without high molecular weight intravenous iron. 4h after BA injection followed by 2h after intravenous iron treatment, inflammatory cytokines were upregulated by BA, but not enhanced by iron treatment. In long term experiments, mice were fed a regular or an iron deficient diet and then treated with intravenous iron or saline 14 days after BA injection. Iron treatment in mice with BA-induced AI was effective 24h after iron administration. In contrast, mice with IDA (on iron deficiency diet) prior to BA-IA required 7d to recover from AI. In these experiments, inflammatory markers were not further induced in iron-treated compared to vehicle-treated BA-injected mice. These results demonstrate that intravenous iron supplementation effectively treated the murine BA-induced AI without further enhancement of the inflammatory response. Studies in humans have to reveal treatment options for AI in patients.

Usefulness of Reticulocyte Hemoglobin Equivalent in Management of Regular Hemodialysis Patients with Iron Deficiency Anemia.

INTRODUCTION: Reticulocyte hemoglobin equivalent (RET-He) is a new parameter for evaluating iron status. This study aims to assess diagnostic value and investigate RET-He as early predictor of response to intravenous iron supplementation. METHODS: Seventy-two regular hemodialysis patients at Adam Malik Hospital were studied from April to May 2011. RET-He was compared with conventional iron parameters for identification of iron deficiency. Fifteen patients with iron deficiency anemia were selected to receive 100 mg iron sucrose intravenous during every dialysis session (2x/weeks) for 4 weeks. RESULTS: Receiver operating characteristic (ROC) curve for RET-He revealed the value of area under the curve was 0.818 (p < 0.0001). Using cutoff level 31.65 pg, RET-He showed 81.5% sensitivity and 61.6% specificity. Serum ferritin (r = 0.499, p < 0.0001) and transferrin saturation/ TSAT (r = 0.592, p < 0.0001) were correlated to RET-He. Significant improvement in hemoglobin, hematocrit and RET-He were found after intervention (p = 0.023, p = 0.049 and p = 0.019, respectively). CONCLUSION: RET-He is a useful marker of iron deficiency and early predictor of response to intravenous iron supplementation in regular hemodialysis patients.

Very low doses of direct intravenous iron in each session as maintenance therapy in hemodialysis patients.

BACKGROUND: Intravenous (IV) iron supplementation is widely used in hemodialysis (HD) patients to treat their periodic losses. However, the ideal dose and frequency is unknown. The goal of the study is to see if a 20 mg dose of iron IV at the end of each session of HD as iron maintenance is better than the iron prior therapy. We analyze the erythropoiesis activity (EA) and functional iron (FI) after four weeks of treatment. METHODS: In 36 patients, we measure reticulocyte count and content of hemoglobin reticulocyte (CHr) as EA and FI markers, respectively, before and after the treatment. Before the study, 23 patients received another different therapy with IV iron as maintenance therapy. RESULTS: Reticulocyte count: 49.7 ± 23.8 × 10(3) before and 47.2 ± 17.2 × 10(3) after the treatment (p= 0.51). The CHr: 34.8 ± 3.7 pg and 34.4 ± 3.5 pg, respectively, (p= 0.35), showing an excellent correlation with the other FI markers (serum iron r = 0.6; p = 0.001; saturation transferrin r = 0.49; p = 0.004); that is not shown with the serum ferritin (r = 0.23; p = 0.192) or the hepcidin levels (r = 0.22; p = 0.251). There was not a correlation between the C-Reactive Protein, reticulocyte count, and CHr. The 13 patients who did not receive the iron prior to the study showed high FI levels, but not an increased of the serum ferritin or the serum hepcidin levels. CONCLUSIONS: The administration of a small quantity of iron at the end of every HD session keeps the EA and the FI levels and allows reducing the iron overload administered and/or decreasing the iron stores markers in some patients.

Diagnosis of Iron-Deficiency Anemia in Chronic Kidney Disease.

Anemia is a common and clinically important consequence of chronic kidney disease (CKD). It is most commonly a result of decreased erythropoietin production by the kidneys and/or iron deficiency. Deciding on the appropriate treatment for anemia associated with CKD with iron replacement and erythropoietic-stimulating agents requires an ability to accurately diagnose iron-deficiency anemia. However, the diagnosis of iron-deficiency anemia in CKD patients is complicated by the relatively poor predictive ability of easily obtained routine serum iron indices (eg, ferritin and transferrin saturation) and more invasive gold standard measures of iron deficiency (eg, bone marrow iron stores) or erythropoietic response to supplemental iron. In this review, we discuss the diagnostic utility of currently used serum iron indices and emerging alternative markers of iron stores.

RNA G-Quadruplex Invasion and Translation Inhibition by Antisense γ-Peptide Nucleic Acid Oligomers.

We have examined the abilities of three complementary γ-peptide nucleic acid (γPNA) oligomers to invade an RNA G-quadruplex and potently inhibit translation of a luciferase reporter transcript containing the quadruplex-forming sequence (QFS) within its 5'-untranslated region. All three γPNA oligomers bind with low nanomolar affinities to an RNA oligonucleotide containing the QFS. However, while all probes inhibit translation with low to midnanomolar IC50 values, the γPNA designed to hybridize to the first two G-tracts of the QFS and adjacent 5'-overhanging nucleotides was 5-6 times more potent than probes directed to either the 3'-end or internal regions of the target at 37 °C. This position-dependent effect was eliminated after the probes and target were preincubated at an elevated temperature prior to translation, demonstrating that kinetic effects exert significant control over quadruplex invasion and translation inhibition. We also found that antisense γPNAs exhibited similarly potent effects against luciferase reporter transcripts bearing QFS motifs having G2, G3, or G4 tracts. Finally, our results indicate that γPNA oligomers exhibit selectivity and/or potency higher than those of other antisense molecules such as standard PNA and 2'-OMe RNA previously reported to target G-quadruplexes in RNA.

Comparison of reticulocyte hemoglobin equivalent with traditional markers of iron and erythropoiesis in pediatric dialysis.

BACKGROUND: Anemia is a major complication for patients on chronic dialysis. Erythropoietin is effective if iron is available, however unnecessary iron supplementation results in iron overload. Reticulocyte hemoglobin equivalent (Ret-He) may be useful for assessing iron status. METHODS: A national retrospective cohort study including all children on chronic dialysis in New Zealand between 2007 and 2013, pairing Ret-He with demographic information, anemia indices, and markers of iron status. RESULTS: In 606 observations, we found a modest relationship between Ret-He and transferrin saturation (TSAT) (r = 0.34, p < 0.001) and a poor correlation between Ret-He and ferritin (r = 0.09, p = 0.04). There was a negative correlation between ferritin and hemoglobin (r = -0.14, p = 0.002), a weak positive correlation between TSAT and hemoglobin (r = 0.12, p = 0.007), and a modest positive correlation between Ret-He and hemoglobin (r = 0.22, p < 0.001). The diagnostic performance of Ret-He to detect absolute iron deficiency (cut-off value 28.9 pg, sensitivity 90 %, specificity 75 %, AUC 0.87) was good. CONCLUSIONS: Ret-He is a more relevant marker of iron status than ferritin and TSAT. This supports prospectively testing Ret-He to distinguish between iron deficiency and suboptimal erythropoietin dosing as competing causes for anemia. Ferritin is an unhelpful biomarker of iron deficiency in this setting.

Dietary folic acid protects against genotoxicity in the red blood cells of mice.

Folate is an essential B vitamin required for the de novo synthesis of purines, thymidylate and methionine. Folate deficiency can lead to mutations and genome instability, and has been shown to exacerbate the genotoxic potential of environmental toxins. We hypothesized that a folic acid (FA) deficient diet would induce genotoxicity in mice as measured by the Pig-a mutant phenotype (CD24-) and micronuclei (MN) in reticulocytes (RET) and red blood cells/normochromatic erythrocytes (RBC/NCE). Male Balb/c mice were fed a FA deficient (0 mg/kg), control (2 mg/kg) or supplemented (6 mg/kg) diet from weaning for 18 wk. Mice fed the deficient diet had 70% lower liver folate (p < 0.001), 1.8 fold higher MN-RET (p < 0.001), and 1.5 fold higher MN-NCE (p < 0.001) than mice fed the control diet. RET(CD24-) and RBC(CD24-) frequencies were not different between mice fed the deficient and control diets. Compared to mice fed the FA supplemented diet, mice fed the deficient diet had 73% lower liver folate (p < 0.001), a 2.0 fold increase in MN-RET (p < 0.001), a 1.6 fold increase in MN-NCE (p < 0.001) and 3.8 fold increase in RBC(CD24-) frequency (p = 0.011). RET(CD24-) frequency did not differ between mice fed the deficient and supplemented diets. Our data suggest that FA adequacy protects against mutagenesis at the Pig-a locus and MN induction in the red blood cells of mice.

Iron depletion in blood donors - Have extended erythrocyte and reticulocyte parameters diagnostic utility?

BACKGROUND: Blood donation is associated with iron depletion, but donor iron status is not usually investigated, as such tests are cumbersome and costly. It would therefore be desirable to have simple, fast and inexpensive tests that give information on a donor's risk of developing iron depletion. In a pilot study we investigated whether novel erythrocyte and reticulocyte parameters can serve this goal. METHODS: In regular blood donors extended red cell parameters were measured using the Abbott CELL-DYN Sapphire hematology analyzer and conventional biochemical tests of iron status. Donors were compared with a regionally matched group of non-donating controls. RESULTS: In the controls, the reference ranges of extended RBC parameters were well comparable to published data. Donors had significantly more microcytic RBC than controls (median 0.9 vs 0.6%), lower serum ferritin concentration (median 43 vs 91 mg/L) and higher soluble transferrin receptor/ferritin index (median 1.60 vs 1.27). Overall 18-28% of the donors were iron depleted. Moreover, 3.3% of donors had iron-restricted erythropoiesis. Microcytic RBC and reticulocyte mean cell hemoglobin content predicted iron depletion with 70% and 64% sensitivities and specificities of 72% and 78%, respectively. When combined these two parameters increased the sensitivity to 82%. CONCLUSIONS: Our results in Swedish blood donors confirm a high prevalence of iron depletion, despite iron supplementation used by about half of the donors. Microcytic RBC and MCHr appeared to be helpful in identifying iron-depleted donors, who might benefit from iron supplementation. We recommend larger prospective investigations in order to confirm and extend the findings of this pilot study.

Genotoxicity assessment of melamine in the in vivo Pig-a mutation assay and in a standard battery of assays.

The genotoxicity of melamine was evaluated with the combined Pig-a mutation/micronucleus assay, the bacterial reverse mutation assay, and the in vitro cytokinesis-block micronucleus assay (CBMN). Five groups of six- to eight-week-old male Sprague-Dawley (SD) rats were given three daily doses of vehicle control (100% pure sesame oil), melamine (500, 1000, and 2000 mg/kg) or positive control (N-ethyl-N-nitrosourea, ENU, 20 mg/kg) by oral gavage. Peripheral blood was sampled pre-dose (day -1) and at time points up to day 60. Pig-a mutant frequencies were determined in total red blood cells (RBCs) and reticulocytes (RETs) as RBC(CD59-) and RET(CD59-) frequencies, on days -1, 15, 29 and 60, and micronucleus frequencies were measured in RETs on day 4. No significant increases in RBC(CD59-) or RET(CD59-) frequencies were observed for the melamine-treated group at any of the time points studied, but the positive control, ENU, induced statistically significant increases compared with the vehicle control. Similar results were obtained in the micronucleus assay. Melamine did not induce statistically significant increases in %MN-RET. In the bacterial reverse mutation assay, melamine was tested from 62.5 to 1000 µg/plate in tester strains TA97a, TA98, TA100, TA102, and TA1535, with and without metabolic activation, and no evidence of toxicity or mutagenicity was observed at any dose tested. In the in vitro CBMN assay, in Chinese hamster ovary (CHO) cells, melamine was tested (75, 150, and 300 µg/mL) in the presence and absence of S9 mix, and no positive increases in the number of cells containing micronuclei were seen. These results suggest that melamine does not exhibit significant genotoxic potential. These data could be valuable for risk assessment purposes and also for further characterizing the new in vivoPig-a gene mutation assay.

Discrimination of various thalassemia syndromes and iron deficiency and utilization of reticulocyte measurements in monitoring response to iron therapy.

Decreased hemoglobinization of red cells resulting in hypochromia and microcytosis are the main features of thalassemia syndromes, and also of iron deficiency anemia (IDA). A simple and reliable method is required to distinguish the two conditions in the routine laboratories. In this study we analyzed the red cell and reticulocyte parameters from 414 samples of various types of thalassemias and IDA and discovered a variety of discriminating criteria including a discrimination index (DI) which should be useful for differential diagnosis. Slightly decreased MCV and CH are suggestive of α-thalassemia 2, Hb CS, and Hb E heterozygotes whereas the increased Rbc counts are obvious in α-thalassemia 1 and ß-thalassemia. In Hb E, the number of microcytic red cells was greater than the number of hypochromic red cells resulting in an increased M/H ratio. Hb H diseases are characterized by a higher number of hypochromic red cells and decreased CHCM, while broadening of hemoglobin concentration histogram results in increased HDW in ß-thalassemia diseases. Iron deficiency anemia results in hypochromic-microcytic red cells and increased RDW. The number of reticulocyte with %High Retic and CHr value were increased in the first month of iron supplementation indicating the response to iron therapy.