Therapy-induced senescent cancer cells exhibit complement activation and increased complement regulatory protein expression.

Therapy-induced senescence (TIS) is a primary response to chemotherapy, contributing to untoward treatment outcomes such as evasion of immunosurveillance. Despite the established role of the complement system in the immune response to cancer, the role of complement in mediating the immune response against senescent tumor cells remains poorly understood. To explore this relationship, we exposed lung adenocarcinoma (A549), breast adenocarcinoma (MCF7) and pancreatic carcinoma (Panc-1) cell lines to sublethal doses of either etoposide or doxorubicin to trigger TIS. Identification of TIS was based on morphological changes, upregulation of the senescence-associated ß-galactosidase, p21Cip1 induction and lamin B1 downregulation. Using immunofluorescence microscopy, quantitative PCR, ELISA of conditioned media and in silico analysis, we investigated complement activation, complement protein expression, C3 levels in the conditioned media of senescent cells and secreted complement proteins as part of the senescence-associated secretory phenotype (SASP), respectively. In cell lines undergoing TIS, complement-related changes included (i) activation of the terminal pathway, evidenced by the deposition of C5b-9 on senescent cells; (ii) an increase in the expression of CD59 and complement factor H and (iii) in A549 cells, an elevation in the expression of C3 with its secretion into the medium. In addition, increased C3 expression was observed in breast cancer samples expressing TIS hallmarks following exposure to neoadjuvant chemotherapy. In conclusion, TIS led to the activation of complement, upregulation of complement regulatory proteins and increased C3 expression. Complement appears to play a role in shaping the cancer microenvironment upon senescence induction.

Investigating the Utility of the SOFA Score and Creating a Modified SOFA Score for Predicting Mortality in the Intensive Care Units in a Tertiary Hospital in Jordan.

Background: The utility of the Sequential Organ Failure Assessment (SOFA) score in predicting mortality in the intensive care unit (ICU) has been demonstrated before, but serial testing in various settings is required to validate and improve the score. This study examined the utility of the SOFA score in predicting mortality in Jordanian ICU patients and aimed to find a modified score that required fewer laboratory tests. Methods: A prospective observational study was conducted at Jordan University Hospital (JUH). All adult patients admitted to JUH ICUs between June and December 2020 were included in the study. SOFA scores were measured daily during the whole ICU stay. A modified SOFA score (mSOFA) was constructed from the available laboratory, clinical, and demographic data. The performance of the SOFA, mSOFA, qSOFA, and SIRS in predicting ICU mortality was assessed using the area under the receiver operating characteristic curve (AUROC). Results: 194 patients were followed up. SOFA score (mean ± SD) at admission was significantly higher in non-survivors (7.5 ± 3.9) compared to survivors (2.4 ± 2.2) and performed the best in predicting ICU mortality (AUROC = 0.8756, 95% CI: 0.8117-0.9395) compared to qSOFA (AUROC = 0.746, 95% CI: 0.655-0.836) and SIRS (AUROC = 0.533, 95% CI: 0.425-0.641). The constructed mSOFA included points for the hepatic and CNS SOFA scores, in addition to one point each for the presence of chronic kidney disease or the use of breathing support; it performed as well as the SOFA score in this cohort or better than the SOFA score in a subgroup of patients with heart disease. Conclusion: SOFA score was a good predictor of mortality in a Jordanian ICU population and better than qSOFA, while SIRS could not predict mortality. Furthermore, the proposed mSOFA score which employed fewer laboratory tests could be used after validation from larger studies.

Anti-SARS-Cov-2 S-RBD IgG Formed after BNT162b2 Vaccination Can Bind C1q and Activate Complement.

Background: The ability of vaccine-induced antibodies to bind C1q could affect pathogen neutralization. In this study, we investigated C1q binding and subsequent complement activation by anti-spike (S) protein receptor-binding domain (RBD) specific antibodies produced following vaccination with either the mRNA vaccine BNT162b2 or the inactivated vaccine BBIBP-CorV. Methods: Serum samples were collected in the period of July 2021-March 2022. Participants' demographic data, type of vaccine, date of vaccination, as well as adverse effects of the vaccine were recorded. The serum samples were incubated with S protein RBD-coated plates. Levels of human IgG, IgA, IgM, C1q, and mannose-binding lectin (MBL) that were bound to the plate, as well as formed C3d, and C5b-9 were compared between different groups of participants. Results: A total of 151 samples were collected from vaccinated (n = 116) and nonvaccinated (n = 35) participants. Participants who received either one or two doses of BNT162b2 formed higher levels of anti-RBD IgG and IgA than participants who received BBIBP-CorV. The anti-RBD IgG formed following either vaccine bound C1q, but significantly more C1q binding was observed in participants who received BNT162b2. Subsequently, C5b-9 formation was significantly higher in participants who received BNT162b2, while no significant difference in C5b-9 formation was found between the nonvaccinated and BBIBP-CorV groups. The formation of C5b-9 was strongly correlated to C1q binding and not to MBL binding, additionally, the ratio of formed C5b-9/bound C1q was significantly higher in the BNT162b2 group. Conclusion: Anti-RBD IgG formed following vaccination can bind C1q with subsequent complement activation, and the degree of terminal complement pathway activation differed between vaccines, which could play a role in the protection offered by COVID-19 vaccines. Further investigation into the correlation between vaccine protection and vaccine-induced antibodies' ability to activate complement is required.

Complement Terminal Pathway Activation is Associated with Organ Failure in Sepsis Patients.

BACKGROUND: Complement plays a pivotal role in the immune response to infection. Several studies demonstrated complement activation in sepsis, yet little is known of the relationship of complement terminal pathway activation and the clinical characteristics of sepsis patients. Therefore, we investigated serum C5, soluble C5b-9 (sC5b-9), and soluble CD59 (sCD59) and their relation to organ failure in sepsis patients in the intensive care unit (ICU). METHODS: In this prospective cohort study, all available patients admitted to the adult ICUs between June 2020 and January 2021 were included. Patients were divided into sepsis and non-sepsis groups according to the Sepsis-3 criteria, serum samples from both groups were investigated for the levels of C5, sC5b-9, and sCD59 using commercial sandwich ELISA kits. RESULTS: We analyzed 79 serum samples, 36 were from sepsis patients. We found that sepsis patients had significantly lower C5 (83.6± 28.4 vs 104.4± 32.0 µg/mL, p = 0.004) and higher sCD59 (380.7± 170.5 vs 288.9± 92.5 ng/mL, p = 0.016). sC5b-9, although higher in sepsis patients, did not reach statistical significance (1.5± 0.8 µg/mL vs 1.3± 0.7 µg/mL, p = 0.293). Sepsis patients who died during their ICU stay had significantly higher sCD59 compared to those who survived (437.0 ± 176.7 vs 267.8 ± 79.7 ng/mL, p = 0.003, respectively). Additionally, C5 and sCD59 both correlated to SOFA score in the sepsis group (rs = -0.44, P = 0.007 and = 0.43, P = 0.009, respectively), and a similar correlation was not found in the non-sepsis group. DISCUSSION: In sepsis patients, levels of C5 and sCD59, but not sC5b-9, correlated to the severity of organ damage measured by SOFA. A similar correlation was not found in non-sepsis patients. This indicated that organ damage associated with sepsis led to a more pronounced terminal pathway activation than in non-sepsis patients, it also indicated the potential of using C5 and sCD59 to reflect sepsis severity.

Characteristics of Adult Sepsis Patients in the Intensive Care Units in a Tertiary Hospital in Jordan: An Observational Study.

Sepsis is a global health issue that is commonly encountered in the intensive care unit (ICU) and is associated with high morbidity and mortality. Available data regarding sepsis in low- and middle-income countries (LMIC) is lacking compared to higher income countries, especially using updated sepsis definitions. The lack of recent data on sepsis in Jordan prompted us to investigate the burden of sepsis among Jordanian ICU patients. We conducted a prospective cohort study at Jordan University Hospital, a tertiary teaching hospital in the capital, Amman. All adult patients admitted to the adult ICUs between June 2020 and January 2021 were included in the study. Patients' clinical and demographic data, comorbidities, ICU length of stay (LOS), medical interventions, microbiological findings, and mortality rate were studied. Descriptive and inferential statistics were used to analyse data from patients with and without sepsis. We observed 194 ICU patients during the study period; 45 patients (23.3%) were diagnosed with sepsis using the Sepsis-3 criteria. Mortality rate and median ICU LOS in patients who had sepsis were significantly higher than those in other ICU patients (mortality rate, 57.8% vs. 6.0%, p value < 0.001, resp., and LOS 7 days vs. 4 days, p value < 0.001, resp.). Additionally, sepsis patients had a higher combined number of comorbidities (2.27 ± 1.51 vs. 1.27 ± 1.09, p value < 0.001). The use of mechanical ventilation, endotracheal intubation, and blood transfusions were all significantly more common among sepsis patients. A causative organism was isolated in 68.4% of sepsis patients with a prevalence of Gram-negative bacteria in 77.1% of cases. While the occurrence of sepsis in the ICU in Jordan is comparable to other regions in the world, the mortality rate of sepsis patients in the ICU remains high. Further studies from LMIC are required to reveal the true burden of sepsis globally.