We report a preliminary experience of adjuvant therapy with Hemoperfusion (HP) in patients with Severe Acute Respiratory Syndrome-CoronaVirus 2 (SARS-CoV2) pneumonia. Currently, there are no approved treatments for CoronaVirus Disease 19 (COVID-19); however, therapeutic strategies based on the preclinical evidence include supportive measures, such as oxygen supplementation, antiviral, and anticoagulant agents. Despite these treatments, 10% of patients worsen and develop severe acute respiratory distress syndrome (ARDS). Since the pathogenic mechanism of ARDS is an uncontrolled inflammatory state, we speculate that removing inflammation effectors from blood may contrast tissue injury and improve clinical outcome. In a scenario of dramatic medical emergency, we conducted an observational study on 9 consecutive patients hospitalized in COVID Intensive Care Unit, where 5 of 9 consecutive patients were treated with HP, due to the emergency overload made it impossible to deliver blood purification in the other 4 patients. COVID-19 was diagnosed through the identification of virus sequences by reverse transcription-PCR on respiratory specimens. All patients had severe pneumonia requiring continuous positive airway pressure. HP was started in all patients 6–7 days after hospital admission. The treated patients (T) received 2 consecutive sessions of HP using CytoSorb cartridge. Our results show a better clinical course of T compared to control patients (C), in fact all T except 1 survived, and only 2 of them were intubated, while all C required intubation and died. Lymphocytopenia worsened in C but not in T. C-reactive protein decreased in both patients, but to a greater extent in T. IL-6, IL-8, and TNF-α decreased after HP, IL-10 did not change. Respiratory function remained stable and did not worsen in T compared to C. The limited sample size and observational study design preclude a sound statement about the potential effectiveness of HP in COVID-19 patients, but our experience suggests a potential therapeutic role of adjuvant CytoSorb HP in the early course of CO­VID-19 pneumonia. A randomized clinical trial is ongoing.

Elderly individuals with chronic disorders tend to develop inflammaging, a condition associated with elevated levels of blood inflammatory markers, and increased susceptibility to chronic disease progression. Native and adaptive immunity are both involved in immune system senescence, kidney fibrosis and aging. The innate immune system is characterized by a limited number of receptors, constantly challenged by self and non-self stimuli. Circulating and kidney resident myeloid and lymphoid cells are all equipped with pattern recognition receptors (PRRs). Recent reports on PRRs show kidney overexpression of toll-like receptors (TLRs) in inflammaging autoimmune renal diseases, vasculitis, acute kidney injury and kidney transplant rejection. TLR upregulation leads to proinflammatory cytokine induction, fibrosis, and chronic kidney disease progression. TLR2 blockade in a murine model of renal ischemia reperfusion injury prevented the escape of natural killer cells and neutrophils by inflammaging kidney injury. Tumor necrosis factor-α blockade in endothelial cells with senescence-associated secretory phenotype significantly reduced interleukin-6 release. These findings should encourage experimental and translational clinical trials aimed at modulating renal inflammaging by native immunity blockade.

MSC (mesenchymal stromal cells) can differentiate into renal adult cells, and have anti-inflammatory and immune-modulating activity. In the present study, we investigated whether MSC have protective/reparative effects in anti-Thy1 disease, an Ab (antibody)-induced mesangiolysis resulting in mesangioproliferative nephritis. We studied five groups of rats: (i) rats injected with anti-Thy1.1 Ab on day 0 (group A); (ii) rats injected with anti-Thy1.1 Ab on day 0+MSC on day 3 (group B); (iii) rats injected with anti-Thy1.1 Ab on day 0+mesangial cells on day 3 (group C); (iv) rats injected with saline on day 0+MSC on day 3 (group D); and (v) rats injected with saline on day 0 (group E). Rats were killed on days 1, 3, 7 and 14. MSC prevented the increase in serum creatinine, proteinuria, glomerular monocyte influx and glomerular histopathological injury. Furthermore, MSC suppressed the release of IL-6 (interleukin-6) and TGF-β (transforming growth factor-β), modulated glomerular PDGF-β (platelet-derived growth factor-β), and reset the scatter factors and their receptors, potentiating HGF (hepatocyte growth factor)/Met and inactivating MSP (macrophage-stimulating protein)/Ron (receptor origin nantaise). Few MSC were found in the kidney. These results indicate that MSC improve anti-Thy 1 disease not by replacing injured cells, but by preventing cytokine-driven inflammation and modulating PDGF-β and the scatter factors, i.e. systems that regulate movement and proliferation of monocytes and mesangial cells.