Hematologically important mutations: X-linked chronic granulomatous disease (fourth update).

Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. CGD patients suffer from severe bacterial and fungal infections. The disease is caused by a lack of superoxide production by the leukocyte enzyme NADPH oxidase. Superoxide and subsequently formed other reactive oxygen species (ROS) are instrumental in killing phagocytosed micro-organisms in neutrophils, eosinophils, monocytes and macrophages. The leukocyte NADPH oxidase is composed of five subunits, of which the enzymatic component is gp91phox, also called Nox2. This protein is encoded by the CYBB gene on the X chromosome. Mutations in this gene are found in about 70% of all CGD patients in Europe and in about 20% in countries with a high ratio of parental consanguinity. This article lists all mutations identified in CYBB and should therefore help in genetic counseling of X-CGD patients' families. Moreover, apparently benign polymorphisms in CYBB are also given, which should facilitate the recognition of disease-causing mutations. In addition, we also include some mutations in G6PD, the gene on the X chromosome that encodes glucose-6-phosphate dehydrogenase, because inactivity of this enzyme may lead to shortage of NADPH and thus to insufficient activity of NADPH oxidase. Severe G6PD deficiency can induce CGD-like symptoms.

Hematologically important mutations: The autosomal forms of chronic granulomatous disease (third update).

Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. CGD patients suffer from severe, recurrent bacterial and fungal infections. The disease is caused by mutations in the genes encoding the components of the leukocyte NADPH oxidase. This enzyme produces superoxide, which is subsequently metabolized to hydrogen peroxide and other reactive oxygen species (ROS). These products are essential for intracellular killing of pathogens by phagocytic leukocytes (neutrophils, eosinophils, monocytes and macrophages). The leukocyte NADPH oxidase is composed of five subunits, four of which are encoded by autosomal genes. These are CYBA, encoding p22phox, NCF1, encoding p47phox, NCF2, encoding p67phox and NCF4, encoding p40phox. This article lists all mutations identified in these genes in CGD patients. In addition, cytochrome b558 chaperone-1 (CYBC1), recently recognized as an essential chaperone protein for the expression of the X-linked NADPH oxidase component gp91phox (also called Nox2), is encoded by the autosomal gene CYBC1. Mutations in this gene also lead to CGD. Finally, RAC2, a small GTPase of the Rho family, is needed for activation of the NADPH oxidase, and mutations in the RAC2 gene therefore also induce CGD-like symptoms. Mutations in these last two genes are also listed in this article.

Multidimensional Response Surface Methodology for the Development of a Gene Editing Protocol for p67phox-Deficient Chronic Granulomatous Disease.

Replacing a faulty gene with a correct copy has become a viable therapeutic option as a result of recent progress in gene editing protocols. Targeted integration of therapeutic genes in hematopoietic stem cells has been achieved for multiple genes using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 system and Adeno-Associated Virus (AAV) to carry a donor template. Although this is a promising strategy to correct genetic blood disorders, it is associated with toxicity and loss of function in CD34+ hematopoietic stem and progenitor cells, which has hampered clinical application. Balancing the maximum achievable correction against deleterious effects on the cells is critical. However, multiple factors are known to contribute, and the optimization process is laborious and not always clearly defined. We have developed a flexible multidimensional Response Surface Methodology approach for optimization of gene correction. Using this approach, we could rapidly investigate and select editing conditions for CD34+ cells with the best possible balance between correction and cell/colony-forming unit (CFU) loss in a parsimonious one-shot experiment. This method revealed that using relatively low doses of AAV2/6 and CRISPR/Cas9 ribonucleoprotein complex, we can preserve the fitness of CD34+ cells and, at the same time, achieve high levels of targeted gene insertion. We then used these optimized editing conditions for the correction of p67phox-deficient chronic granulomatous disease (CGD), an autosomal recessive disorder of blood phagocytic cells resulting in severe recurrent bacterial and fungal infections and achieved rescue of p67phox expression and functional correction of CD34+-derived neutrophils from a CGD patient.

Second Report of Chronic Granulomatous Disease in Jordan: Clinical and Genetic Description of 31 Patients From 21 Different Families, Including Families From Lybia and Iraq.

Chronic granulomatous Disease (CGD) is a rare innate immunodeficiency disorder caused by mutations in one of the six genes (CYBA, CYBB, NCF1, NCF2, NCF4, and CYBC1/EROS) encoding the superoxide-producing nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase complex in phagocytes. In the Western population, the most prevalent form of CGD (about two-thirds of all cases) is the X-linked form (X-CGD) caused by mutations in CYBB. The autosomal recessive forms (AR-CGD), due to mutations in the other genes, collectively account for the remaining one-third of CGD cases. We investigated the clinical and molecular features of 22 Jordanian, 7 Libyan, and 2 Iraqi CGD patients from 21 different families. In addition, 11 sibling patients from these families were suspected to have been died from CGD as suggested by their familial and clinical history. All patients except 9 were children of consanguineous parents. Most of the patients suffered from AR-CGD, with mutations in CYBA, NCF1, and NCF2, encoding p22 phox , p47 phox , and p67 phox proteins, respectively. AR-CGD was the most frequent form, in Jordan probably because consanguineous marriages are common in this country. Only one patient from non-consanguineous parents suffered from an X910 CGD subtype (0 indicates no protein expression). AR670 CGD and AR220 CGD appeared to be the most frequently found sub-types but also the most severe clinical forms compared to AR470 CGD. As a geographical clustering of 11 patients from eight Jordanian families exhibited the c.1171_1175delAAGCT mutation in NCF2, segregation analysis with nine polymorphic markers overlapping NCF2 indicates that a common ancestor has arisen ~1,075 years ago.

The Highest Cited Papers in Brucellosis: Identification Using Two Databases and Review of the Papers' Major Findings.

Citation classics represent the highest impact work in a given field. We aim to identify and analyze the most frequently cited papers on brucellosis. We used the databases Scopus and Web of Science to determine the most frequently cited papers. The most cited fifty papers in each database were identified. We then ranked the papers according to the highest citation count recorded from any of the two databases. The most frequently cited paper received 964 citations and was by DelVecchio VG et al. reporting the complete genomic sequencing of Brucella melitensis. The papers were published in 30 journals led by the "Infection and Immunity" journal and the "Veterinary Microbiology" journal (each had 7 papers). Citation classics in brucellosis were all in English except one in French and were mostly of basic science type. In addition, we noticed that 12 articles that were identified among the highest fifty articles in one database were missed by the other database and vice versa. Therefore, we suggest that searching in more than one database would detect additional citation classics.

Seroprevalence of measles, mumps, rubella, and varicella amongphysicians and nurses in Jordan.

BACKGROUND/AIM: Measles, mumps, rubella, and varicella can affect susceptible healthcare workers who might subsequently spread the infection to susceptible patients and workers. Here, we aim to determine the seroprevalence of these infections among physicians and nurses and to compare the history of varicella with the results of varicella antibodies among study participants. MATERIALS AND METHODS: Two randomly selected groups, one group of physicians and one of nurses, from a university hospital in Jordan were interviewed and their serum IgG antibodies were measured. RESULTS: The physicians and nurses group had 252 and 241 participants, respectively. The physicians group had significantly more males and younger participants. The percentage of individuals in the physician and nurse groups with positive antibodies to measles was 75.4% and 75.1%, respectively; mumps, 88.5% and 94.2%; rubella, 89.3% and 87.1%; and varicella, 92.1% and 92.5%. Immunity was similar between the 2 groups except for mumps, where significantly more nurses were immune. The positive and negative predictive values for the history of varicella to predict immunity in all participants were 95% and 13.5%, respectively. CONCLUSION: A small but important proportion of our healthcare workers are still susceptible to measles, mumps, rubella, and varicella. In addition, the recall history to varicella showed suboptimal ability to predict immunity.