This study aimed to determine if there is an association between ABO blood type and severity of COVID-19 defined by intubation or death as well as ascertain if there is variability in testing positive for COVID-19 between blood types. In a multi-institutional study, all adult patients who tested positive for COVID-19 across five hospitals were identified and included from March 6th to April 16th, 2020. Hospitalization, intubation, and death were evaluated for association with blood type. Univariate analysis was conducted using standard techniques and logistic regression was used to determine the independent effect of blood type on intubation and/or death and positive testing. During the study period, there were 7648 patients who received COVID-19 testing throughout the institutions. Of these, 1289 tested positive with a known blood type. A total of 484 (37.5%) were admitted to hospital, 123 (9.5%) were admitted to the ICU, 108 (8.4%) were intubated, 3 (0.2%) required ECMO, and 89 (6.9%) died. Of the 1289 patients who tested positive, 440 (34.2%) were blood type A, 201 (15.6%) were blood type B, 61 (4.7%) were blood type AB, and 587 (45.5%) were blood type O. On univariate analysis, there was no association between blood type and any of the peak inflammatory markers (peak WBC, p = 0.25; peak LDH, p = 0.40; peak ESR, p = 0.16; peak CRP, p = 0.14) nor between blood type and any of the clinical outcomes of severity (admission p = 0.20, ICU admission p = 0.94, intubation p = 0.93, proning while intubated p = 0.58, ECMO p = 0.09, and death p = 0.49). After multivariable analysis, blood type was not independently associated with risk of intubation or death (referent blood type A; blood type B:

Type V collagen (COLV) is a regulatory fibril-forming collagen. It has at least three different molecular isoforms-a1(V) 2 a2(V), a1(V) 3, and a1(V)a2(V)a3(V)-formed by combinations of three different polypeptide a chains-a1(V), a2(V), and a3(V). COL V is a relatively minor collagen of the extracellular matrix (ECM). Morphologically, COLV occurs as heterotypic fibrils with type I collagen (COLI), microfilaments, or 12-nm-thick fibrils. COLV is synthesized in various mesenchymal cells and its gene expression is modulated by TGF-b and growth factors. While resistant to digestion by interstitial collagenases, native and denatured COLV are degraded by metalloproteinases and gelatinases, thereby promoting ECM remodeling. COLV interacts with matrix collagens and structural proteins, conferring structural integrity to tissue scaffolds. It binds matrix macromolecules, modulating cellular behavior, and functions. COLV coassembles with COLI into heterotypic fibrils in the cornea and skin dermis, acting as a dominant regulator of collagen fibrillogenesis. COLV deficiency is associated with loss of corneal transparency and classic EhlersDanlos syndrome, while COLV overexpression is found in cancer, granulation tissue, inflammation, atherosclerosis, and fibrosis of lungs, skin, kidneys, adipose tissue, and liver. COLV isoform containing the a3(V) chain is involved in mediating pancreatic islet cell functions. In the liver, COLV is a minor but regular component of the ECM. Increases in COLV are associated with both early and advanced hepatic fibrosis. The neoepitopes of COLV have been shown to be a useful noninvasive serum biomarker for assessing fibrotic progression and resolution in experimental hepatic fibrosis. COLV is multifunctional in health, disease, and fibrosis. Anat Rec, 299:613-629, 2016. V C 2016 Wiley Periodicals, Inc.Key words: collagen V synthesis and degradation; collagen V deficiency and overexpression; collagen V in disease and fibrosis; collagen V neoepitopes; hepatic fibrosis biomarker

The insulin hexamer is resistant to degradation and fibrillation, which makes it an important quaternary structure for its in vivo storage in Zn(2+)- and Ca(2+)-rich vesicles in the pancreas and for pharmaceutical formulations. In addition to the two Zn(2+) ions that are required for its formation, three other species, Zn-coordinating anions (e.g., Cl(-)), Ca(2+), and phenols (e.g., resorcinol), bind to the hexamer and affect the subunit conformation and stability. The contributions of these four species to the thermodynamics of insulin unfolding have been quantified by differential scanning calorimetry and thermal unfolding measurements to determine the extent and nature of their stabilization of the insulin hexamer. Both Zn(2+) and resorcinol make a significant enthalpic contribution, while Ca(2+) primarily affects the protein heat capacity (solvation) by its interactions in the central cation-binding cavity, which is modulated by the surrounding subunit conformations. Coordinating anions have a negligible effect on the stability of the hexamer, even though subunits shift to an alternate conformation when these anions bind to the Zn(2+) ions. Finally, Zn(2+) in excess of the two that are required to form the hexamer further stabilizes the protein by additional enthalpic contributions.

Since the onset of the COVID-19 pandemic, a concentrated research effort has been undertaken to elucidate risk factors underlying viral infection, severe illness, and death. Recent studies have investigated the association between blood type and COVID-19 infection. This article aims to comprehensively review current literature and better understand the impact of blood type on viral susceptibility and outcomes.