Background: Anemia is an important public health and clinical problem. Observational studies have linked iron deficiency and anemia in children with many poor outcomes, including impaired cognitive development; however, iron supplementation, a widely used preventive and therapeutic strategy, is associated with adverse effects. Primary-school–aged children are at a critical stage in intellectual development, and optimization of their cognitive performance could have long-lasting individual and population benefits. In this study, we summarize the evidence for the benefits and safety of daily iron supplementation in primary-school–aged children. Methods: We searched electronic databases (including MEDLINE and Embase) and other sources (July 2013) for randomized and quasi-randomized controlled trials involving daily iron supplementation in children aged 5–12 years. We combined the data using random effects meta-analysis. Results: We identified 16 501 studies; of these, we evaluated 76 full-text papers and included 32 studies including 7089 children. Of the included studies, 31 were conducted in low- or middle-income settings. Iron supplementation improved global cognitive scores (standardized mean difference 0.50, 95% confidence interval [CI] 0.11 to 0.90, p = 0.01), intelligence quotient among anemic children (mean difference 4.55, 95% CI 0.16 to 8.94, p = 0.04) and measures of attention and concentration. Iron supplementation also improved age-adjusted height among all children and age-adjusted weight among anemic children. Iron supplementation reduced the risk of anemia by 50% and the risk of iron deficiency by 79%. Adherence in the trial settings was generally high. Safety data were limited. Interpretation: Our analysis suggests that iron supplementation safely improves hematologic and nonhematologic outcomes among primary-school–aged children in low- or middle-income settings and is well-tolerated.
The transcription factor interferon regulatory factor 4 (IRF4) is critical for the development, maintenance, and function of plasma cells. The mechanism by which IRF4 exerts its action in mature plasma cells has been elusive due to the death of all such cells upon IRF4 loss. While we identify apoptosis as a critical pathway for the death of plasma cells caused by IRF4 loss, we also determine that IRF4 did not regulate the intrinsic apoptotic pathway directly. By using an inducible IRF4 deletion system in the presence of the overexpression of anti-apoptotic BCL2, we identify genes whose expression is coordinated by IRF4 and that in turn specify plasma cell identity and mitochondrial homeostasis.
Recent studies have demonstrated that the immunomodulatory drugs (IMiDs) lead to the degradation of the transcription factors Ikaros and Aiolos. However, why their loss subsequently leads to multiple myeloma (MM) cell death remains unclear. Using CRISPR-Cas9 genome editing, we have deleted IKZF1/Ikaros and IKZF3/Aiolos in human MM cell lines to gain further insight into their downstream gene regulatory networks. Inactivation of either factor alone recapitulates the cell intrinsic action of the IMiDs, resulting in cell cycle arrest and induction of apoptosis. Furthermore, evaluation of the transcriptional changes resulting from their loss demonstrates striking overlap with lenalidomide treatment. This was not dependent on reduction of the IRF4-MYC “axis,” as neither protein was consistently downregulated, despite cell death occurring, and overexpression of either factor failed to rescue for Ikaros loss. Importantly, Ikaros and Aiolos repress the expression of interferon-stimulated genes (ISGs), including CD38, and their loss led to the activation of an interferon-like response, contributing to MM cell death. Ikaros/Aiolos repressed CD38 expression through interaction with the nucleosome remodeling and deacetylase complex in MM. IMiD-induced loss of Ikaros or treatment with interferon resulted in an upregulation of CD38 surface expression on MM cells, priming for daratumumab-induced NK cell-mediated antibody-dependent cellular cytotoxicity. These results give further insight into the mechanism of action of the IMiDs and provide mechanistic rationale for combination with anti-CD38 monoclonal antibodies.
4 April 2005 in Clinical & Experimental Ophthalmology