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The liver is a central organ in the human body, coordinating several key metabolic roles. The structure of the liver which consists of the distinctive arrangement of hepatocytes, hepatic sinusoids, the hepatic artery, portal vein and the central vein, is critical for its function. Due to its unique position in the human body, the liver interacts with components of circulation targeted for the rest of the body and in the process, it is exposed to a vast array of external agents such as dietary metabolites and compounds absorbed through the intestine, including alcohol and drugs, as well as pathogens. Some of these agents may result in injury to the cellular components of liver leading to the activation of the natural wound healing response of the body or fibrogenesis. Long-term injury to liver cells and consistent activation of the fibrogenic response can lead to liver fibrosis such as that seen in chronic alcoholics or clinically obese individuals. Unidentified fibrosis can evolve into more severe consequences over a period of time such as cirrhosis and hepatocellular carcinoma. It is well recognized now that in addition to external agents, genetic predisposition also plays a role in the development of liver fibrosis. An improved understanding of the cellular pathways of fibrosis can illuminate our understanding of this process, and uncover potential therapeutic targets. Here we summarized recent aspects in the understanding of relevant pathways, cellular and molecular drivers of hepatic fibrosis and discuss how this knowledge impact the therapy of respective disease.

Background and Aim There is a paucity of data on the clinical presentations and outcomes of Corona Virus Disease-19 (COVID-19) in patients with underlying liver disease. We aimed to summarize the presentations and outcomes of COVID-19-positive patients and compare with historical controls. Methods Patients with known chronic liver disease who presented with superimposed COVID-19 (n = 28) between 22 April 2020 and 22 June 2020 were studied. Seventy-eight cirrhotic patients without COVID-19 were included as historical controls for comparison. Results A total of 28 COVID-19 patients (two without cirrhosis, one with compensated cirrhosis, sixteen with acute decompensation [AD], and nine with acute-on-chronic liver failure [ACLF]) were included. The etiology of cirrhosis was alcohol (n = 9), non-alcoholic fatty liver disease (n = 2), viral (n = 5), autoimmune hepatitis (n = 4), and cryptogenic cirrhosis (n = 6). The clinical presentations included complications of cirrhosis in 12 (46.2%), respiratory symptoms in 3 (11.5%), and combined complications of cirrhosis and respiratory symptoms in 11 (42.3%) patients. The median hospital stay was 8 (7-12) days. The mortality rate in COVID-19 patients was 42.3% (11/26), as compared with 23.1% (18/78) in the historical controls (p = 0.077). All COVID-19 patients with ACLF (9/9) died compared with 53.3% (16/30) in ACLF of historical controls (p = 0.015). Mortality rate was higher in COVID-19 patients with compensated cirrhosis and AD as compared with historical controls 2/17 (11.8%) vs. 2/48 (4.2%), though not statistically significant (p = 0.278). Requirement of mechanical ventilation independently predicted mortality (hazard ratio 13.68). Both non-cirrhotic patients presented with respiratory symptoms and recovered uneventfully. Conclusion COVID-19 is associated with poor outcomes in patients with cirrhosis, with worst survival rates in ACLF. Mechanical ventilation is associated with a poor outcome.

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Cell surface structures termed knobs are one of the most important pathogenesis related protein complexes deployed by the malaria parasite Plasmodium falciparum at the surface of the infected erythrocyte. Despite their relevance to the disease, their structure, mechanisms of traffic and their process of assembly remain poorly understood. In this study, we have explored the possible role of a parasite-encoded Hsp40 class of chaperone, namely PFB0090c/PF3D7_0201800 (KAHsp40) in protein trafficking in the infected erythrocyte. We found the gene coding for PF3D7_0201800 to be located in a chromosomal cluster together with knob components KAHRP and PfEMP3. Like the knob components, KAHsp40 too showed the presence of PEXEL motif required for transport to the erythrocyte compartment. Indeed, sub-cellular fractionation and immunofluorescence analysis (IFA) showed KAHsp40 to be exported in the erythrocyte cytoplasm in a stage dependent manner localizing as punctuate spots in the erythrocyte periphery, distinctly from Maurer’s cleft, in structures which could be the reminiscent of knobs. Double IFA analysis revealed co-localization of PF3D7_0201800 with the markers of knobs (KAHRP, PfEMP1 and PfEMP3) and components of the PEXEL translocon (Hsp101, PTEX150). KAHsp40 was also found to be in a complex with KAHRP, PfEMP3 and Hsp101 as confirmed by co-immunoprecipitation assay. Our results suggest potential involvement of a parasite encoded Hsp40 in chaperoning knob assembly in the erythrocyte compartment.