Virtual Screening and Biological Evaluation of Potential PD-1/PD-L1 Immune Checkpoint Inhibitors as Anti-Hepatocellular Carcinoma Agents

Blockade of the programmed cell death-1/programmed cell death ligand-1 (PD-1/PD-L1) immune checkpoint pathway is an efficient immunotherapeutic modality that provided significant advances in cancer treatment especially in solid tumors highly resistant to traditional therapy. Monoclonal antibodies (mAbs) and small-molecule inhibitors are the two main strategies used to block this axis with mAbs suffering from many limitations. Accordingly, the current alternative is the development of small-molecule PD-1/PD-L1 inhibitors. Here, we present a sequential virtual screening (VS) protocol involving pharmacophore screening followed by molecular docking for the discovery of novel PD-L1 inhibitors. The VS protocol resulted in the discovery of eight novel compounds. A 100 ns MD simulation showed two compounds, H4 and H6, exhibiting a stable binding mode at the PD-L1 dimer interface. Upon evaluation of their immunological activities, the two compounds induced higher cytokines levels (IL-2, IL-6, and INF-γ) relative to BMS-202, 72 h post treatment of PBMCs of HCC patients. Thus, the discovered hits represent potential leads for the development of novel classes targeting the PD-L1 receptor as anti-hepatocellular carcinoma agents.

Evaluation of factors affecting patients' refusal of HCV treatment in a cohort of Egyptian patients

BACKGROUND

Treatment refusal, defined as active refusal of a patient to receive treatment despite physician recommendations, has not been extensively evaluated before in hepatitis C virus in the era of direct acting antivirals.

OBJECTIVE

To investigate the reasons for refusal to receive hepatitis C virus treatment in Egypt.

METHODS

an observational study conducted between July 2018 and November 2019 in Egypt. Enrollment was done to all patients who refused to get hepatitis C virus treatment during the national screening and treatment campaign. Reasons for their refusal were identified using a questionnaire as an instrument for data collection.

RESULTS

Out of the 220 280 Egyptian hepatitis C virus patients who did not show up to start treatment and were contacted to get therapy, only 84 patients (0.038%) refused to receive treatment. The main reason for their refusal was having concerns about treatment (82.14%) and their main concern was the fear of adverse events (85.5%). Other causes of refusal were non-satisfactory experience at treatment centers (13.09%) and patients preferred to receive complementary and alternative medicines (4.7%). Most patients (65.4%) trusted the efficacy of directly acting antivirals for hepatitis C. None of the study participants was found to suffer from any psychiatric morbidity and the average score of the GHQ-12 was 10.7155.

CONCLUSION

Proper health education and awareness regarding hepatitis C virus treatment safety and efficacy is needed to increase treatment acceptance rates.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulins using chemiluminescence immunoassay and its correlation with neutralizing antibodies

BACKGROUND

Neutralizing antibodies (NAbs) against SARS-CoV-2 infection have a pivotal role in protective immune response; however, their measurement requires specialized facilities. We evaluated the degree of correlation between NAbs and anti-SARS-CoV-2 IgG/total Ig antibodies detected by chemiluminescent immunoassay in asymptomatic and previously symptomatic SARS-CoV-2 patients.

METHODS

A total of 1241 participants (previously symptomatic patients and asymptomatic individuals), who were screened for SARS-CoV-2 infection by RT-PCR or serology, were enrolled in our study. Sera were analyzed for the presence of anti-spike-1(S1)-SARS-CoV-2 IgG/total Ig antibodies, using Ortho Clinical Diagnostics, USA. A signal/cut-off value (S/CO) ≥ 1 was considered reactive. NAbs were measured in 103 random samples from groups using microneutralization assay, with titer ≥ 1:10 being considered positive.

RESULTS

Asymptomatic (n = 229) and 261 previously symptomatic individuals with positive serology and negative RT-PCR were finally included. Significant higher anti-S1-IgG titers were seen in asymptomatic individuals (P < 0.0001). Conversely, anti-S1-total Ig titers were significantly higher in previously symptomatic (P < 0.0001). NAbs were detected in both groups, however, higher titers were seen in previously symptomatic patients. There is a correlation between NAbs and both IgG/total anti-S1-SARS-CoV-2 antibodies (r = 0.47, P < 0.0001 and r = 0.49, P < 0.0001, respectively). IgG and total Ig could predict a neutralization titer of ≥ 1:160 at S/CO >4.44 and >65 with AUC 0.69 and 0.67, respectively.

CONCLUSION

Asymptomatic SARS-CoV-2 infection can produce comparable antibodies response to previously symptomatic individuals, however higher neutralization activity was seen in the previously symptomatic. Anti-S1-SARS-CoV-2 IgG/total Ig antibodies showed a correlation with neutralization activity and can be used to estimate the presence of protective immunity.

Effect of Ramadan intermittent fasting on inflammatory markers, disease severity, depression, and quality of life in patients with inflammatory bowel diseases: A prospective cohort study

Background

Intermittent fasting (IF) during the month of Ramadan is part of the religious rituals of Muslims. The effect of intermittent fasting on disease activity in inflammatory bowel diseases (IBD) is still unknown. This is the first study to assess the effect of IF during Ramadan on inflammatory markers in patients diagnosed with IBD. The effects on clinical disease activity, quality of life, and levels of depression were also assessed.

Methods

Patients diagnosed with ulcerative colitis (UC) or Crohn’s disease (CD) who intended to observe Ramadan fasting were recruited. The following were assessed immediately before and at the end of Ramadan: Serum CRP and stool calprotectin, partial Mayo score, Harvey Bradshaw index (HBI), Simple IBD questionnaire (SIBDQ), and Hamilton depression scale questionnaire.

Results

80 patients diagnosed with IBD were recruited (60 UC, 20 CD). Serum CRP and stool calprotectin did not show a significant change before vs after fasting (median CRP 0.53 vs 0.50, P value = 0.27, Calprotectin 163 vs 218 respectively, P value = 0.62). The partial Mayo score showed a significant rise after fasting (median 1 before vs 1 after fasting, mean: 1.79 vs 2.33 respectively, P value = 0.02). Harvey-Bradshaw index did not show a significant change after fasting (median 4 vs 5, P value = 0.4). Multiple linear regression revealed that older age and a higher baseline calprotectin were associated with a higher change in Mayo score after fasting (P value = 0.02 and P value = 0.01, respectively). No significant change was detected in SIBDQ or Hamilton depression scale scores.

Conclusions

In patients diagnosed with UC, IF during Ramadan was associated with worsening of clinical parameters, the effect was more pronounced in older patients and those with higher baseline calprotectin levels. However, IF during Ramadan was not associated with an adverse effect on objective inflammatory markers (CRP and calprotectin).

Perspectives and Management Strategies for Acute Colonic Intramural Hematoma

Acute intramural hematoma of the colon is a rarely encountered clinical condition with diverse precipitating factors. Different acute and chronic complications emerge following hematoma formation, mandating high clinical suspicion for early diagnosis and optimum management. CECT represents the cornerstone for the proper demonstration of colonic hematomas and possible detection of complications as well as the underlying etiology. There are multiple strategies for management of intramural hematoma and treatment should be tailored according to the etiology and the clinical condition of the patient, reserving surgical intervention for unstable or complicated cases. Endoscopic management of colonic hematomas offers a promising minimally invasive modality with potential safety and efficacy.

Prevalence of SARS-CoV-2 infection and dynamics of antibodies response among previously undiagnosed healthcare workers in a university hospital: A prospective cohort study

BACKGROUND

Healthcare workers (HCWs) are a presumed high-risk population for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Identifying factors associated with seroprevalence can help establish better practices in healthcare settings. In this study, we evaluate prevalence of SARS-CoV-2 infection among previously undiagnosed HCWs and describe profiling of antibody responses against SARS-CoV-2, including neutralizing antibodies (NAbs).

METHODS

We analyzed a cohort of 386 HCWs in a university hospital in Egypt and 725 volunteers not affiliated to any healthcare facility (non-healthcare workers - NHCWs). Participants provided a nasopharyngeal swab and serum samples for SARS-CoV-2 nucleic acid and SARS-CoV-2-specific antibodies, respectively. HCWs who tested positive by either test were sequentially monitored.

RESULTS

At baseline, point prevalence of viral carriage was 11.4% in HCWs (n = 44/386) and 11.9% in NHCWs (86/725). The cumulative prevalence of SARS-CoV-2 infection among HCWs considering all studies was 25.6%, which was statistically lower than in NHCWs (41.0%). Prevalence was greatest among janitorial staff (45.9%) and the most affected departments were gastroenterology (31.1%), and emergency medicine (30.0%). Prior anosmia, fever or headache were associated with higher odds of positivity for SARS-CoV-2 infection. Regarding serial antibody measurements, RT-PCR-positive HCWs displayed IgG detection rates of 29.5%, 70% and 60% at visit 1, visit 2 and visit 3, respectively with slow decline of median IgG antibody titers, whereas, corresponding detection rates for total Ig antibodies were 50%, 90.3%, and 88.9%, respectively with increasing median titers. NAbs measured at each time point were positively correlated with total Ig levels, whereas IgG levels were positively correlated with NAbs at visit 1 and visit 3.

CONCLUSION

Our results demonstrate lower cumulative prevalence of SARS-CoV-2 infection in HCWs than general population and suggest that asymptomatic HCWs exhibit considerable IgG and total Ig antibodies response as well as NAbs for up to 120 days, with positive correlation in between.

The association of adiponectin gene polymorphisms with susceptibility and progression of NAFLD in a cohort of Egyptian patients

Background

Several genetic polymorphisms have been proven to play a key role in the progression of non-alcoholic fatty liver disease (NAFLD) from simple steatosis to NASH with fibrosis. Our aim was to study the effect of single nucleotide polymorphisms (SNPs) in the adiponectin gene, namely rs266729 and rs3774261, on susceptibility to NAFLD and disease progression.

Results

There was a definitive association between polymorphisms of the studied SNPs and NAFLD. Among rs266729, CG was significantly higher among patients than controls showing increased risk for NAFLD (P<0.05). AA genotype of the rs3774261 variant was significantly lower in patients than in controls (P value< 0.001) while AG and GG genotypes were significantly higher in patients than in controls (P value<0.05); A allele was significantly higher among controls (P=0.019) which might have a protective effect. None of the variants correlated significantly with the degree of steatosis. Using multivariate regression analysis, there was no significant correlation with any of the independent risk factors to the degree of steatosis.

Conclusions

There was an association between polymorphisms of the studied SNPs of rs266729 and rs3774261 of the adiponectin gene and NAFLD.

SARS-CoV-2 infection among asymptomatic healthcare workers of the emergency department in a tertiary care facility

•

SARS-CoV-2 was found in 14.3 % of healthcare workers in emergency department.

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Rapid serological tests for SARS-CoV-2 can increase the diagnostic yield.

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Screening of asymptomatic healthcare workers for SARS-CoV-2 is advised.

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Infection control among transportation and cleaning staff should be stressed.

Background

Healthcare workers (HCWs) represent a high-risk category during the coronavirus disease 2019 (COVID-19) pandemic crisis, with frontline HCWs at emergency departments (EDs) may be at an even higher risk. Determining the spread of infection among HCWs may have implications for infection control policies in hospitals. This study aimed to detect severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection among asymptomatic HCWs of the ED of a large tertiary center in Cairo, Egypt.

Methods

The study was conducted from June 1^st to June 14^th, 2020. All the recommended national and international indications on infection control measures were followed. Two hundred and three HCWs were included in the study and tested by nasopharyngeal swab (NPS) and rapid serological test (RST). Descriptive statistical analyses were used to summarize the data.

Results

Of the 203 HCWs, 29 (14.3 %) tested positive by real-time reverse transcription polymerase chain reaction (RT-PCR). Thirty-seven (18.2 %) HCWs tested positive with RST: 20 with both IgM and IgG; 14 with IgM only, and 3 with IgG only. Age, gender, and/or occupation were not risk factors for SARS-CoV-2 infection.

Conclusions

Point prevalence of COVID-19 in asymptomatic HCWs in ED of tertiary care facility is 14.3 % by RT-PCR. This illustrates the importance of screening all HCWs regardless of symptoms, and the need for strict measures in securing HCWs to reduce transmission from healthcare facilities to the community during the current pandemic.

SARS-CoV-2 infection among healthcare workers of a gastroenterological service in a tertiary care facility

BACKGROUND AND STUDY AIMS

Frontlines healthcare workers (HCWs) during the coronavirus disease 2019 (COVID-19) pandemic are at increased risk of infection by SARS-CoV-2, but there are limited data on the prevalence of COVID-19 among HCWs in Egypt. This study aimed to assess SARS-CoV-2 infection among HCWs providing gastroenterological services.

SUBJECTS AND METHODS

Seventy-four HCWs at the gastroenterological service of Al-Manial University Hospital, the main hospital of the largest tertiary university hospitals complex in Egypt (Kasr Al-Ainy Faculty of Medicine, Cairo University) were tested using real-time reverse transcription-polymerase chain reaction (RT-PCR) on nasopharyngeal samples, and rapid serological IgM/IgG tests (RST). A questionnaire was used to collect demographic, occupational and clinical data.

RESULTS

Of the 74 HCWs, 10 tested positive by RT-PCR (13.5%). In 9/74 (12.2%) HCWs, antibodies could be detected by RST: three with both IgM and IgG lines; six with IgM line only and none with IgG line only. Frequency of positive tests was more among subjects with minor symptoms compared to completely asymptomatic HCWs (50% vs 16.1%, respectively). Neither age, gender or occupation was a risk factor for SARS-CoV-2 infection.

CONCLUSIONS

Point prevalence of COVID-19 in gastroenterology HCWs is 13.5% by RT-PCR. Continued measures are warranted to assure HCWs safety and reduce transmission from healthcare settings to the community during COVID-19 pandemic. Presence of positive test results among asymptomatic HCWs illustrates the importance of screening all HCWs irrespective of symptoms.

Genetic Variants in nicotinamide-N-methyltransferase (NNMT) gene are related to the stage of non-alcoholic fatty liver disease diagnosed by controlled attenuation parameter (CAP)-fibroscan

BACKGROUND AND AIMS

Various genetic polymorphisms play a key-role in the pathogenesis of NAFLD and progression to NASH with fibrosis to cirrhosis. We aimed to study the association between single-nucleotide polymorphisms (SNPs) in NNMT gene, namely rs694539 and the development of different stages of NAFLD diagnosed by controlled attenuation parameter (CAP) of FibroScan Echosens®.

METHODS

Transient elastography (FibroScan®) with controlled attenuation parameter (CAP) measurement was performed in 81 NAFLD patients (35 of them with liver biopsy) and 80 non-NAFLD controls. The accuracy of CAP and FibroScan for the detection and quantification of hepatic steatosis/fibrosis, respectively, was assessed based on liver biopsy aspect. Genetic variants of NNMT gene rs694539 were analyzed using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

According to BMI (kg/m2), among the patients, 17 (21%) were overweight, 56 (69.1%) obese, and 8 (9.9%) morbidly obese. CAP and FibroScan diagnosed steatosis/fibrosis correlated significantly with liver biopsy. There was a significant association between polymorphisms of rs694539-NNMT gene and NAFLD presence and stages. The mutant type (AA-genotype) was found in 33% NAFLD patients versus 1.2% controls (P<0.001), whereas the wild type (GG-genotype) was present in 21% versus 63.8% controls (P<0.001). Moreover, the AA-genotype significantly correlated with the steatosis degree by CAP but not the fibrosis degree by FibroScan. Multivariate regression analysis of all the independent risk factors showed non-significant correlations with the degree of steatosis on CAP. However, by using a stepwise approach, waist circumference showed significance as an independent predictor of NAFLD.

CONCLUSIONS

Polymorphisms in rs694539-NNMT gene (mutant AA-genotype) could be a genetic risk factor for developing NAFLD and NASH (indicating susceptibility for progression and complications). Individuals with wild type (GG-genotype) are at less risk of NAFLD development. CAP and FibroScan efficiently diagnosed steatosis and fibrosis.