The role of lymphoid tissue SPARC in the pathogenesis and response to treatment of multiple myeloma.

Background: Despite the significant progress in the treatment of multiple myeloma (MM), the disease remains untreatable and its cure is still an unmet clinical need. Neoplastic transformation in MM is initiated in the germinal centers (GCs) of secondary lymphoid tissue (SLT) where B cells experience extensive somatic hypermutation induced by follicular dendritic cells (FDCs) and T-cell signals. Objective: We reason that secreted protein acidic and rich in cysteine (SPARC), a common stromal motif expressed by FDCs at the origin (SLTs) and the destination (BM) of MM, plays a role in the pathogenesis of MM, and, here, we sought to investigate this role. Methods: There were 107 BM biopsies from 57 MM patients (taken at different time points) together with 13 control specimens assessed for SPARC gene and protein expression and compared with tonsillar tissues. In addition, regulation of myeloma-promoting genes by SPARC-secreting FDCs was assessed in in vitro GC reactions (GCRs). Results: SPARC gene expression was confirmed in both human primary (BM) and secondary (tonsils) lymphoid tissues, and the expression was significantly higher in the BM. Sparc was detectable in the BM and tonsillar lysates, co-localized with the FDC markers in both tissues, and stimulation of FDCs in vitro induced significantly higher levels of SPARC expression than unstimulated controls. In addition, SPARC inversely correlated with BM PC infiltration, ISS staging, and ECOG performance of the MM patients, and in vitro addition of FDCs to lymphocytes inhibited the expression of several oncogenes associated with malignant transformation of PCs. Conclusion: FDC-SPARC inhibits several myelomagenic gene expression and inversely correlates with PC infiltration and MM progression. Therapeutic induction of SPARC expression through combinations of the current MM drugs, repositioning of non-MM drugs, or novel drug discovery could pave the way to better control MM in clinically severe and drug-resistant patients.

Anti-Factor H Antibodies in Egyptian Children with Hemolytic Uremic Syndrome.

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is an important cause of acute kidney injury in children. It is primarily caused by dysregulation of the complement alternative pathway due to genetic mutations, mainly in complement factor H genes, or due to anti-factor H autoantibodies (anti-FH), leading to uncontrolled overactivation of the complement system. Early diagnosis and treatment of autoimmune HUS (AI-HUS) is essential and leads to a favorable outcome. METHODS: Fifty pediatric HUS patients and 50 age- and sex-matched controls were included in the study. Patients were subjected to full history taking, clinical examination, and laboratory testing. All candidates were subjected to an assessment of anti-FH in serum by a homemade enzyme-linked immunosorbent assay technique. RESULTS: A high frequency of serum anti-FH was detected in our aHUS patients. The disease onset of AI-HUS was mainly observed in March and April, with significantly higher rates in school-aged males. All patients who started immunosuppressives early together with plasmapheresis upon detection of their anti-FH had complete renal function recovery. CONCLUSION: The high frequency of AI-HUS revealed in Egyptian HUS children in our study highlights the importance of implementing anti-FH testing in Egypt to provide early recognition for immediate proper management, including early immunosuppressive therapy, and hence improving patient outcomes.

Genetic variations in DNA-repair genes (XRCC1, 3, and 7) and the susceptibility to hepatocellular carcinoma in a cohort of Egyptians.

Chronic hepatitis C (CHC) is a worldwide etiology of chronic hepatic insult particularly in Egypt. DNA-repair systems are responsible for maintaining genomic integrity by countering threats posed by DNA lesions. Deficiency in the repair capacity due to genetic alterations in DNA-repair genes can lead to genomic instability and increased risk of cancer development. The present work aimed at studying the possible association between XRCC1-G28152A (rs25487), XRCC3-C18067T (rs861539), and XRCC7-G6721T (rs7003908) single nucleotide polymorphisms (SNPs) and the susceptibility to hepatocellular carcinoma (HCC) in Egyptian population. The study was conducted on 100 newly diagnosed HCC patients and 100 age- and sex-matched healthy controls. Laboratory workup revealed that all HCC patients have chronic hepatitis C viral infection. Genotyping of the studied SNPs was performed by real-time PCR. The heteromutant genotype of XRCC1 (GA) conferred an almost two-fold increased risk of HCC (OR , 2.35; 95% CI, 1.33-4.04). Regarding XRCC7, the heteromutant (TG) genotype conferred a two-fold increased risk of HCC (OR , 2.17; 95% CI, 1.23-3.82). Coinheritance of the polymorphic genotypes of XRCC1 and 7 was significantly higher in HCC cases than controls and was associated with an 11-fold increased risk of HCC (OR , 11.66; 95% CI, 2.77-49.13). The frequency of XRCC3 polymorphic genotypes in HCC patients was close to that of the controls.

The effect of different methods of leucoreduction on plasma coagulation factors.

Removal of leucocytes from blood products, namely leucoreduction, improves the safety of blood transfusion by reducing adverse events associated with the incidental transfusion of leucocytes. Coagulation factors might be compromised during leucoreduction because of exposure of plasma to a variety of filter materials. The aim of the current study was to assess the effect of different methods of prestorage leucofiltration (apheresis and whole blood filters) on prothrombin time, international normalized ratio, partial thromboplastin time and factors V and VIII. There was a significant prolongation of prothrombin time as well as elevation of international normalized ratio in plasma after leucoreduction (14.5 ±â€Š0.7 s vs. 13.9 ±â€Š0.7 s, P = 0.008 and 1.14 ±â€Š0.07 vs. 1.09 ±â€Š0.07, P = 0.005, respectively). Also, there was a statistically significant prolongation of activated partial thromboplastin time in nonleucoreduced plasma (55.6 ±â€Š9.9 s vs. 43.2 ±â€Š12.8 s, P = 0.001). There was no significant filtration effect on factors V and VIII levels. Furthermore, there was no significant difference in factors V and VIII levels between plasma filtered by inline whole blood filters and apheresis machine. Leucodepleted plasma originating from both inline whole blood filter and apheresis machine maintained satisfactory levels of factors V and VIII.

Peripheral expression of hepcidin gene in Egyptian ß-thalassemia major.

Iron overload is the major cause of morbidity and mortality in transfusion dependent ß-thalassemia major patients. There is a sophisticated balance of body iron metabolism of storage and transport which is regulated by several factors including the peptide hepcidin. Hepcidin is the main iron regulatory molecule; it is secreted mainly by the liver and other tissues including monocytes and lymphocytes. Expression of hepcidin in such cells is unclear and has been studied in few reports with controverted result. Peripheral expression of hepcidin was measured using quantitative real time PCR (qRT-PCR) in 50 ß-thalassemia major patients, in addition to 20 healthy volunteers as a control group. Hepcidin levels in ß-thalassemia major patients showed statistically significant decrease in comparison to the control group, and was correlated to cardiac iron stores (T2*). However, hepcidin level was not different among the patients according to the HCV status or whether splenectomized or not. In conclusion; peripheral expression of hepcidin, in iron overloaded ß-thalassemia major patients, is a reflection of hepatic expression. It can be used as a molecular predictor for the severity of cardiac iron overload and can be used as a future target for therapy in ß-thalassemia major patients.