Shuttle peptide delivers base editor RNPs to rhesus monkey airway epithelial cells in vivo

Gene editing strategies for cystic fibrosis are challenged by the complex barrier properties of airway epithelia. We previously reported that the amphiphilic S10 shuttle peptide non-covalently combined with CRISPR-associated (Cas) ribonucleoprotein (RNP) enabled editing of human and mouse airway epithelial cells. Here, we derive the S315 peptide as an improvement over S10 in delivering base editor RNP. Following intratracheal aerosol delivery of Cy5-labeled peptide in rhesus macaques, we confirm delivery throughout the respiratory tract. Subsequently, we target CCR5 with co-administration of ABE8e-Cas9 RNP and S315. We achieve editing efficiencies of up-to 5.3% in rhesus airway epithelia. Moreover, we document persistence of edited epithelia for up to 12 months in mice. Finally, delivery of ABE8e-Cas9 targeting the CFTR R553X mutation restores anion channel function in cultured human airway epithelia. These results demonstrate the therapeutic potential of base editor delivery with S315 to functionally correct the CFTR R553X mutation in respiratory epithelia.

Reciprocal mutations of lung-tropic AAV capsids lead to improved transduction properties

Considerable effort has been devoted to developing adeno-associated virus (AAV)-based vectors for gene therapy in cystic fibrosis (CF). As a result of directed evolution and capsid shuffling technology, AAV capsids are available with widespread tropism for airway epithelial cells. For example, AAV2.5T and AAV6.2 are two evolved capsids with improved airway epithelial cell transduction properties over their parental serotypes. However, limited research has been focused on identifying their specific cellular tropism. Restoring cystic fibrosis transmembrane conductance regulator (CFTR) expression in surface columnar epithelial cells is necessary for the correction of the CF airway phenotype. Basal cells are a progenitor population of the conducting airways responsible for replenishing surface epithelial cells (including secretory cells and ionocytes), making correction of this cell population vital for a long-lived gene therapy strategy. In this study, we investigate the tropism of AAV capsids for three cell types in primary cultures of well-differentiated human airway epithelial (HAE) cells and primary human airway basal cells. We observed that AAV2.5T transduced surface epithelial cells better than AAV6.2, while AAV6.2 transduced airway basal cells better than AAV2.5T. We also investigated a recently developed capsid, AAV6.2FF, which has two surface tyrosines converted to phenylalanines. Next, we incorporated reciprocal mutations to create AAV capsids with further improved surface and basal cell transduction characteristics. Lastly, we successfully employed a split-intein approach using AAV to deliver an adenine base editor (ABE) to repair the CFTR R553X mutation. Our results suggest that rational incorporation of AAV capsid mutations improves AAV transduction of the airway surface and progenitor cells and may ultimately lead to improved pulmonary function in people with CF.

CFTR-rich ionocytes mediate chloride absorption across airway epithelia

The volume and composition of a thin layer of liquid covering the airway surface defend the lung from inhaled pathogens and debris. Airway epithelia secrete Cl- into the airway surface liquid through cystic fibrosis transmembrane conductance regulator (CFTR) channels, thereby increasing the volume of airway surface liquid. The discovery that pulmonary ionocytes contain high levels of CFTR led us to predict that ionocytes drive secretion. However, we found the opposite. Elevating ionocyte abundance increased liquid absorption, whereas reducing ionocyte abundance increased secretion. In contrast to other airway epithelial cells, ionocytes contained barttin/Cl- channels in their basolateral membrane. Disrupting barttin/Cl- channel function impaired liquid absorption, and overexpressing barttin/Cl- channels increased absorption. Together, apical CFTR and basolateral barttin/Cl- channels provide an electrically conductive pathway for Cl- flow through ionocytes, and the transepithelial voltage generated by apical Na+ channels drives absorption. These findings indicate that ionocytes mediate liquid absorption, and secretory cells mediate liquid secretion. Segregating these counteracting activities to distinct cell types enables epithelia to precisely control the airway surface. Moreover, the divergent role of CFTR in ionocytes and secretory cells suggests that cystic fibrosis disrupts both liquid secretion and absorption.

Shuttle Peptide Delivers Base Editor RNPs to Rhesus Monkey Airway Epithelial Cells In Vivo

Gene editing strategies for cystic fibrosis are challenged by the complex barrier properties of airway epithelia. We previously reported that the amphiphilic S10 shuttle peptide non-covalently combined with CRISPR-associated (Cas) ribonucleoprotein (RNP) enabled editing of human and mouse airway epithelial cells. Here, to improve base editor RNP delivery, we optimized S10 to derive the S315 peptide. Following intratracheal aerosol of Cy5-labeled peptide cargo in rhesus macaques, we confirmed delivery throughout the respiratory tract. Subsequently, we targeted CCR5 with co-administration of ABE8e-Cas9 RNP and S315. We achieved editing efficiencies of up to 5.3% in rhesus airway epithelia. Moreover, we documented persistence of edited epithelia for up to 12 months in mice. Finally, delivery of ABE8e-Cas9 targeting the CFTR R553X mutation restored anion channel function in cultured human airway epithelial cells. These results demonstrate the therapeutic potential of base editor delivery with S315 to functionally correct the CFTR R553X mutation in respiratory epithelia.

Functional correction of CFTR mutations in human airway epithelial cells using adenine base editors

Mutations in the CFTR gene that lead to premature stop codons or splicing defects cause cystic fibrosis (CF) and are not amenable to treatment by small-molecule modulators. Here, we investigate the use of adenine base editor (ABE) ribonucleoproteins (RNPs) that convert A•T to G•C base pairs as a therapeutic strategy for three CF-causing mutations. Using ABE RNPs, we corrected in human airway epithelial cells premature stop codon mutations (R553X and W1282X) and a splice-site mutation (3849 + 10 kb C > T). Following ABE delivery, DNA sequencing revealed correction of these pathogenic mutations at efficiencies that reached 38-82% with minimal bystander edits or indels. This range of editing was sufficient to attain functional correction of CFTR-dependent anion channel activity in primary epithelial cells from CF patients and in a CF patient-derived cell line. These results demonstrate the utility of base editor RNPs to repair CFTR mutations that are not currently treatable with approved therapeutics.

Prevalence, management and ethnobotanical investigation of hypertension in two Guinean urban districts

ETHNOPHARMACOLOGICAL RELEVANCE

Hypertension is an important public health challenge in low- and middle-income countries, and in many African countries including Guinea medicinal plants are still widely used for its treatment.

MATERIALS AND METHODS

The objective of this study was to determine the prevalence of hypertension in two Guinean urban districts (Pounthioun and Dowsare), to describe its management and to collect information on traditional herbal remedies. A total of 316 participants entered the study, 28.2% (89/316) men and 71.8% (227/316) women. Of these, 181 were from Dowsare (50 men and 131 women) and 135 from Pounthioun (39 men and 96 women). The mean age of subjects was 40.8 ± 14.0 years (range18 - 88years), while the majority of subjects (63.3% or 200/316) were 45-74 years old.

RESULTS

The overall prevalence of hypertension was 44.9% (142/316): 46.4% (84/181) from Dowsare and 43.0% (58/135) from Pounthioun. Ethnobotanical investigations among hypertensive patients led to the collection of 15 plant species, among which Hymenocardia acida leaves and Uapaca togoensis stem bark were the most cited. Phytochemical investigation of these two plant species led to the isolation and identification of isovitexin and isoorientin from H. acida, and betulinic acid and lupeol from U. togoensis.

CONCLUSION

The presence of these constituents in Hymenocardia acida leaves and Uapaca togoensis stem bark may at least in part support their traditional use against hypertension in Guinea.

[Using CT to diagnose brain tumors at the Point G Hospital in Mali]

The authors report 27 cases of cerebral tumours in 22 men and 5 women age 1 to 81. Clinical symptoms were dominated by cranial hypertension (59.3%), focal motor impairment involving cranial nerves (51.9%.) and seizures due to epilepsy (44.4%). The main tumors detected with CT scan include glyoma (.5 cases), craniopharyngioma (3 cases), adenoma (3 cases), medulloblastoma (3 cases), and metastasis (3 cases). The supra tentoriel was predominant (76.9%). Neurosurgery was performed in 6 patients and 21 cases received medical treatment. We fund 13 cases of death. In conclasion, cerebral tumours are very severe pathologies because of the high mortality associated with. CT scan has contributed to diagnose the lesions, show their topography and to determinte the histological nature. Neurosurgery is necessary for the treatment of these lesions.

5-Fluorouracil-related severe toxicity: a comparison of different methods for the pretherapeutic detection of dihydropyrimidine dehydrogenase deficiency

5-Fluorouracil (5-FU)-related early toxicity, due to a metabolic deficiency, is rare but is potentially severe and even lethal (0.1%). It is due to dihydropyrimidine dehydrogenase (DPYD) gene polymorphism or some epigenetic factors. The detection of metabolic change could prevent severe toxicity, but until now it has not been carried out in clinical practice.

PURPOSE

To find the simplest and most accurate pretherapeutic test to predict DPD deficiency in patients treated with 5-FU by comparing different approaches.

RESULTS

Two hundred and fifty two French Caucasian patients treated by 5-FU infusion were studied. A two-step strategy, combining firstly SNP detection and uracil plasma measurement, followed, in cases where metabolic deficiency was suspected, by dihydrouracil/uracil ratio determination to confirm deficiency and to determine the optimum 5-FU dosage, appeared the best approach, with 83% and 82% sensitivity and specificity, respectively.

CONCLUSION

These data support the future use of this approach, suitable to clinical practice, as screening test to identify DPD deficiency before 5-FU-based therapy.

[Contribution of ultrasound in the diagnosis of the complications of intramuscular injection in children]

During a prospective study conducted at the rehabilitation Center of the physically handicapped persons and at the mother-child Hospital in Bamako, the authors report 50 cases of neuromuscular complications of the quinine intramuscular injection in the child. The scan revealed muscular calcifications in 37 cases (740%), abscesses, in 7 cases (14%) and muscular inflammations in 6 cases (12%). Xray of the affected limb was not systematic: it has been performed in four children in the case of a subjacent bone involment. It showed calcifications in two cases. If muscular abscess is easily diagnosed by clinical exam it is not the case for calcifications. The scan allows to set up a precise mapping of the muscular lesions, to determine their type and size. It also helps the clinicians in their therapeutic attitude. Medical treatment associated with rehabilitation has been carried out in 40 patients (80%) and surgery in 10 patients (20%).

[Evaluation of cocoa oil for individual protection against Simulium damnosum s.i]

Thanks to larviciding and distribution of ivermectine, transmission of onchocerciasis was virtually halted in all countries covered by the WHO Onchocerciasis Control Program (OCP). However as a result of this success vector control has been stopped in most areas covered by the program and a recrudescence of files is an increasing problem. In some rural communities fly biting hinders normal agricultural activity. Since local farmers cannot afford ground larviciding, many rely on topical repellents. For this reason, development of an inexpensive method of individual protection is a major priority. The purpose of this study carried out in the savannah area of the Côte d'Ivoire was to assess the repellent properties of cocoa oil, which is frequently used in some rural areas of the Côte d'Ivoire to prevent fly biting. Results showed that cocoa oil provides excellent protection against Simulium damnosum s.l.

[Soninke and Poular models of migration from the valley of the Senegal River]

"Soninke and Poular migration from the valley of the Senegal River [has] historical pre-colonial roots. The colonial and post-colonial economies have confirmed and reinforced the migratory models of both ethnic groups. The data of [a] 1982 survey highlight similarities and differences in the demographic indicators of [these] migrations, which can be explained in relation to their respective pasts." (SUMMARY IN ENG AND SPA)

[Integration of demographic factors in the characterization of risk areas for sleeping sickness in Côte d'Ivoire]

The purpose of this study was to classify the risk for transmission of African human trypanosomiasis (sleeping sickness) according to population and settlement densities in four different areas of Zoukougbeu, Cote d'Ivoire, where the exact location of cases reported since 1990 is known. Epidemiological risk indexes were calculated from entomological data obtained from three surveys and analyzed with respect to presence of patients and occupancy rate in each area. Results indicated that there was a risk of transmission near the village of Bahigbeu II where the population density is between 30 and 40 inhabitants per km2 and settlement density is 4 per km2. There was also a risk in less inhabited areas such as Ouatigbeu where the population density is less than 30 inhabitants per km2 and dwelling density less than 4 per km2. In fact, cases are regularly reported in Ouatigbeu but never in Bahigbeu II. Based on these findings, we conclude that, while land occupancy can be considered as a risk factor for sleeping sickness, other factors such as human mobility must be taken into account to characterize risk areas and predict outbreaks.

[Defects in peroxidation of erythrocyte phospholipids in sickle cell trait]

The sickle cell disease pathophysiology is provided by several events including deoxyhemoglobin S polymerization and hemorrheological troubles. Classically, such disorders have been known to concern only the homozygous SS and heterozygous SC profiles. However, troubles are more and more described since early years in the sickle cell trait patients and the pathogenesis factors are unknown. Our study focussed on phospholipids which are the basic and functional constituent elements of erythrocyte plasmic membrane. Assaying the membrane lipids extracted by Folch method and lipid standards (cholesterol, phosphatidic acid, lysophosphatidyl-choline, phosphatidyl-choline, lysophosphatidyl-ethanolamine, phosphatidyl-ethanolamine, sphingomyelin) was carried out by HPLC among 91 sickle cell trait patients as compared to 78 healthy subjects. The main abnormalities observed were an empoverishement in phosphatidyl-choline contrasting with an accumulation of membrane lysophosphatidyl-choline, lysophosphatidyl-ethanolamine, phosphatidic acid and sphingomyelin in sickle cell patients. These results suggest that sickle cell trait harmlessness is not actual. The accumulation of lysophosphatidyl-choline, by its cytolytic biomembrane perturbing properties, predispose therefore the sickled red cell to the haemolysis phenomena and allow to forecast deeper disturbances among homozygous subjects. These morbid disorders attributable to lipid peroxidation would justify an antioxidant treatment during the sickle cell disease.

[Onchocerciasis and epilepsy. Epidemiological survey in Mali]

A door-to-door survey was conducted in 18 villages in Mali with a total of 5,243 inhabitants classified according to the endemicity of onchocerciasis. Each epileptic was matched with two controls. The survey protocol included the following steps in cases and controls: census taking, socioeconomic data, screening for epilepsy, clinical examination, laboratory testing to detect parasites in stools and urine, and snip-test. The crude prevalence of epilepsy was 13.35 per 1,000 (n = 70). Epidemiological study provided a number of valuable demographic insights concerning age at onset, type of seizure activity during seizure and personal and family medical history. A transverse study showed that the prevalence of epilepsy was not significantly higher (p = 9.09) in zones of high endemicity of onchocerciasis (16.1 per 1000) than in zones of low endemicity (10.8 per 1000). Case-control findings showed evidence of onchocerciasis in 22.4 p. 100 of epileptics and 21.7 p. 100 of controls (odds ratio = 1.02 IC 95 p. 100: 0.4-2.19, not significant). Various risk factors including genetic factors and low socio-economic status could explain the trend toward a higher incidence of epilepsy as well as higher morbidity rates in zones of high endemicity of onchocerciasis.

Impact of the development of agricultural land on the transmission of sleeping sickness in Daloa, Côte d'Ivoire

Although tools to control sleeping sickness do exist, their use is difficult; areas where intervention is most required often cannot be targeted for lack of appropriate risk indicators. The importance of human behaviour and habits in the manifestation of the disease is clear. In the development of effective new approaches to the control of the disease, information must be gathered about human populations, and their interaction with the environment, in rural as well as in urban and peri-urban areas. The results of a study carried out in Daloa show that use of some methods for the development of agricultural land leads to increased human-vector contact and, as a result, increased risk of sleeping sickness. Such land-management methods may therefore be useful as risk indicators for transmission. Transmission does not occur in the town of Daloa itself but in surrounding areas under cultivation. The use of the epidemiological risk index seems to be inappropriate in urban (and perhaps peri-urban) areas. The results emphasise not only the importance of environmental and demographic data in elucidating the epidemiology of human trypanosomiasis but also the need for further investigations in peri-urban areas.

[Microfilarial loads of onchocerca and experimental vectorial capacity of Simulium soubrense-Simulium sanctipauli group in the forest zone of Ivory Coast]

Mass treatment programs using ivermectin are now beginning in forest areas and simuli will soon be feeding on individuals with low microfilarial loads (probably < 10). Most previous reports have involved higher mean loads (range: 14-6950. The purpose of this study was to ascertain the impact of low microfilarial loads on the number of infecting larvae present at the end of a parasite cycle in the Simulium soubrense-Simulium sanctipauli group and on availability for transmission to man by inoculation. Tests were carried out on five subjects from a forest area of southwest Ivory Coast who were infected with onchocerciasis and presented mean microfilarial loads of 1, 5, 10, 20, and 100. Findings showed a direct correlation between microfilarial load (1, 5, 20, and 100) and intake of microfilaria per dissected female. Similarly there was a correlation between microfilarial loads (1, 5, 10, 20, and 100), quantity of infected females, and number of infecting larvae per infected female. Parasite output was variable but decreased as microfilarial load increased. This study suggests that the experimental vectorial capacity of simuli is similar in subjects presenting onchocerciasis with high and low microfilarial loads.

Detection of serum antibodies in tuberculosis patients

Sera of 14 bacteriological confirmed pulmonary tuberculosis and 16 non-tuberculotic or healthy controls were sampled in Ignace Deen University Hospital in Conakry, Quinea. Samples were examined for IgG and IgM antibodies by means of enzyme-linked immunosorbent assay (ELISA) using sonicated M. bovis BCG and M. avium antigens and were tested for antibodies to HIV-1/HIV-2 as well. Median of IgG antibody titres to M. bovis BCG antigen was 1:445 and differed significantly from that of the control group (1:149). The median of IgM antibody titres was 1:79.1 and did not differ statistically from that of control group (1:69.3) as well as the antibody titres against M. avium antigen in the IgG and IgM classes for both analyzed serum groups. Seven of tested TB patients sera were positive for antibodies against HIV-1. The median of IgG antibody titres against M. bovis BCG antigen was 1:442 not differing significantly from values of remaining TB patients as well as the IgM antibody titre (1:109).

Social and epidemiological aspects of guinea worm control

Dracunculiasis prevention should be simple: in a population at risk, everyone may be protected by the filtration of drinking water. The research described in this paper allowed the authors to follow the acceptance of new information by villagers in nine localities in Mali. Two strategies were studied: safe water supply (bore-hole or cement lined wells) plus health education on the one hand, and health education alone (based on filtration) on the other. Safe water supply is undoubtedly an effective strategy whereas the success of the health education intervention is uncertain. This experience showed that health education as the only means of control failed due to a lack of social cohesion or of coordinated group-action. Also, when dracunculiasis control is not a population's priority goal, the constraints on systematic filtration are too great and a tendency to discontinue the filtration process occurs. On the other hand, when dracunculiasis is considered to be a serious problem by the population, new information about systematic filtration is better assimilated and leads to behavioural changes. In order that the goal of eradicating dracunculiasis by 1995 should not be an utopic dream, it is necessary to prioritize the allocation of clean rural water supply projects only to those endemic villages where the conditions that allow for health education to be successful are met.

[Sequela of hand burns in children: 32 cases followed and treated in the Plastic Surgery and Reconstruction department of the University Hospital Center of Treichville, Abidjan]

An investigation on the effects of hand burns has been undertaken about 32 children admitted in the plastic surgery outpatients Department. Accident occurs among the lower class population and heat is the major factor pointed out. The most frequent effects are hand palmar contracture. The surgical treatment completed with the functional re-education has given very good results in 79% cases. However the cheloid contractures are the most difficult to cure. Indeed the authors insist or the prevention and the creation of a center of burned patients and a plastic surgery Service to take care of patients whose life prognostic is optimistic.

Analysis of trifluralin and other dinitroaniline herbicide residues by zero-order and derivative ultraviolet spectrophotometry

The utility of zero-order and first- and second-derivative ultraviolet (UV) spectrophotometry for the identification of benfluralin, trifluralin, isopropalin and oryzalin is discussed. These four herbicides were determined by zero-order and first-derivative UV spectrophotometry, with linear calibration graphs established between 50 and 100 concentration units and limits of detection ranging from 1 to 7 micrograms ml-1. The application of these techniques to the residue analysis of fortified soils and niebe and peanut leaves is described. Trifluralin residues were found to be 6.7, 8 and 1.7 micrograms ml-1 in samples of fortified soils, niebe leaves and peanut leaves, respectively. Isopropalin residues were found to range from 62 to 154 micrograms ml-1 in samples of fortified niebe leaves.

[Human immunodeficiency virus (HIV) infection in Mali]

This review summarises epidemiological and clinical data of HIV infection who was recognized in Mali since 1985. The most important rate of seropositivity for HIV is observed in the prostitutes group (40%). The estimated seroprevalence for adult population is between 1% and 5%. 46 cases for AIDS are reported in both sexes. The mean age is 35 years. Main signs are weight loss (91%), fever (80%), diarrhea (70%) and lymphadenopathy (50%). Three among the five cases of Kaposi's sarcoma are aggressive. 19.5% of AIDS have antibodies to HIV1, 41.3% to HIV2 and 39.1% to HIV1 and HIV2. Death rate is more than 50%. These data are compared with other countries of Africa.

Liver fluke infections of cattle in Mali. An abattoir survey on prevalence and geographic distribution

Six hundred and ninety two cattle, slaughtered in various abattoirs in Mali between August 1983 and November 1984 were examined for evidence of Fasciola gigantica and Dicrocoelium hospes infections. A great variation in geographic prevalence was observed. Sufficient knowledge was acquired to demonstrate both the importance of fascioliasis in some areas and also the high prevalence of D. hospes in other areas. We suggest that the difference in prevalence from one geographic area to another is influenced by local climatic conditions, presence or absence of rivers and lakes, and differences in livestock management practices by various ethnic groups.

[Porocephalosis caused by Armillifer (Nettorhynchus) armillatus, Wyman 1847, (Pentastomida) in a steer and a pig (Mali and Upper Volta)]

Deux cas de porocéphalose observés à l'abattoir de Bobo-Dioulasso (République de Haute-Volta) concernant un bovin de provenance malienne et un porcin d'origine voltaïque sont décrits. Les auteurs soulignent l'importance de cette parasitose qui peut affecter l'homme par consommation de viande d'animaux infestés