Innate Immunity as an Executor of the Programmed Death of Individual Organisms for the Benefit of the Entire Population.

In humans, over-activation of innate immunity in response to viral or bacterial infections often causes severe illness and death. Furthermore, similar mechanisms related to innate immunity can cause pathogenesis and death in sepsis, massive trauma (including surgery and burns), ischemia/reperfusion, some toxic lesions, and viral infections including COVID-19. Based on the reviewed observations, we suggest that such severe outcomes may be manifestations of a controlled suicidal strategy protecting the entire population from the spread of pathogens and from dangerous pathologies rather than an aberrant hyperstimulation of defense responses. We argue that innate immunity may be involved in the implementation of an altruistic programmed death of an organism aimed at increasing the well-being of the whole community. We discuss possible ways to suppress this atavistic program by interfering with innate immunity and suggest that combating this program should be a major goal of future medicine.

Effects of off-pump versus on-pump coronary artery bypass grafting: apoptosis, inflammation, and oxidative stress.

BACKGROUND: It has been suggested that off-pump coronary artery bypass grafting (CABG) surgery reduces myocardial ischemia-reperfusion injury, postoperative systemic inflammatory response, and oxidative stress. The aim of this study was to measure serum malondialdehyde (MDA), high-sensitivity C-reactive protein (hs-CRP), M30, and M65 levels and to investigate the relationship between M30 levels and oxidative stress and inflammation in patients undergoing on-and off-pump CABG surgery. METHODS: Fifty patients were randomly assigned to on-pump or off-pump CABG surgery (25 patients off-pump and 25 on-pump CABG surgery), and blood samples were collected prior to surgery, and 30 minutes, 60 minutes, 6 hours, and 24 hours after CABG surgery. RESULTS: Compared to the on-pump group, serum MDA levels at 30 minutes, 60 minutes, 6 hours, and 24 hours after the CABG surgery were significantly lower in the off-pump group (P=.001, P=.001, P=.001, and P=.001, respectively). Serum M30 levels were found to be elevated in both groups, returning to baseline at 24 hours. When compared to baseline, the hs-CRP level reached its peak at 24 hours at 13.28±5.32 mg/dL in the on-pump group, and 15.44±4.02 mg/dL in the off-pump group. CONCLUSION: CABG surgery is associated with an increase in inflammatory markers and serum M30 levels, indicating epithelial/endothelial apoptosis in the early period.

Would blockage of cytokines improve the outcome of pancreatic islet transplantation?

It has been estimated that up to 60% of pancreatic islet tissue undergoes apoptosis within the first several days post-transplantation. This strongly suggests the involvement of an inflammatory event other than alloantigen-specific immune reaction following islet transplantation which contributes to partial destruction of grafts. Inflammatory cytokines including IL-1beta, TNF-alpha and IFN-gamma are implicated in the pancreatic islet beta-cell death and functional loss during autoimmune diabetes and also seem to be involved in early loss of islet mass in islet transplantation. Inflammatory cytokines and free oxygen radicals released in situ could cause apoptosis and the functional impairment of islets after islet transplantation and graft failure. It can be hypothesized that preventing destruction of transplanted islets using cytokine blockade could be helpful in improving islet transplantation outcome. Several approaches have been made based on this hypothesis to examine the effect of inflammatory blockade on the islets survival and functional islet mass. Further investigations are required to identify most efficient way for block of cytokine-induced damage in pancreatic islets transplantation.

Erythropoietin in the critically ill - is it more than just blood?

Erythropoietin (EPO) has been in clinical use for the treatment of anemia for over 15 years. Recently it has been demonstrated that EPO has actions other than stimulating the bone marrow. It has been suggested that due to its tissue protecting effect, EPO may be effective in improving outcome in the critically ill.

Disease activity improvement in rheumatoid arthritis treated with tumor necrosis factor-α inhibitors correlates with increased soluble Fas levels.

OBJECTIVE: Rheumatoid arthritis (RA) is characterized by chronic synovial inflammation and hyperplasia. Tumor necrosis factor-α (TNF-α) plays a pivotal role in RA by interfering with the Fas-Fas ligand (FasL) proapoptotic pathway. We investigated the circulating levels of soluble Fas (sFas) and soluble FasL (sFasL), and their possible correlation with disease activity and improvement after anti-TNF-α treatment in RA. METHODS: Serum levels of sFas and sFasL were measured by quantitative ELISA in 52 patients with RA before and after 3 months of anti-TNF-α treatment (adalimumab, n = 32; infliximab, n = 20). Disease activity measures [Disease Activity Score at 28 joints-erythrocyte sedimentation rate (DAS28-ESR), C-reactive protein (CRP)] were recorded before and after treatment. Forty age-matched and sex-matched healthy subjects served as controls. RESULTS: No significant differences in serum sFas levels were detected between anti-TNF-α-naive patients with RA and controls. After anti-TNF-α treatment, serum sFas levels significantly increased in patients with RA compared to both anti-TNF-α-naive patients and controls. Increased sFas levels inversely correlated with disease activity variables (DAS28-ESR: r = -0.739, CRP: r = -0.636, both p < 0.001). No significant differences in sFasL levels were detected in patients with RA before and after anti-TNF-α treatment. CONCLUSION: In RA, an increase in sFas levels closely correlates with improvement in disease activity induced by TNF-α inhibitors, suggesting their ability to modulate Fas-mediated synoviocyte apoptosis.

Islet transplantation: factors in short-term islet survival.

Islet transplantation has the potential to cure type 1 diabetes. In recent years, the proportion of patients achieving initial insulin independence has improved, but longer term outcomes remain poor compared to those for whole pancreas transplants. This review article will discuss factors affecting islet yield and viability leading up to transplantation and in the immediate post-transplant period.

Premature vascular damage in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a disease associated with a striking increase in the risk of premature cardiovascular (CV) complications due to accelerated atherosclerosis. Traditional CV risk factors seem to be less important predictors of CV events than the presence of active SLE. Immune dysregulation characteristic of lupus appears to play the dominant role in atherogenesis. While both SLE-specific and non-specific mechanisms have been proposed to play a prominent role in the induction of premature vascular damage in this disease, the exact etiology remains unclear. We have proposed that an imbalance between vascular damage and repair likely induced by Interferon- could play a prominent role in the induction of accelerated atherosclerosis in SLE. This review summarizes some of the proposed mechanisms that may promote accelerated vascular damage in lupus and explores potential targets for CV risk prevention in this patient population.

Improvement of recombinant protein production by an anti-apoptotic protein from hemolymphof Lonomia obliqua

Apoptosis is a major problem in animalcell culture during production of biopharmaceuticals, such as recombinant proteins or viral particles. In the present work baculovirus-insect cell expression system (BEVS/IC) is used as model to produce rotaviruslike-particles, composed by three layers of three different viral proteins (VP2, VP6 and VP7). In this model baculovirus infection also induces host celldeath. Herein a new strategy to enhance cell life span and to increase recombinant rotavirus protein productionof BEVS/IC system was developed. This strategy relies on hemolymph from Lonomia oblique (total extracts or a semi-purified fraction) medium supplementation. The total extract and a purified fraction from hemolymph of Lonomia obliqua were able toprotect Sf-9 cell culture against apoptosis triggered by oxidative stress (using the pro-oxidant agents tert butylhydroperoxide and hydrogen peroxide) and by baculovirus infection. Furthermore, hemolymph enhance final recombinant protein production, as it was observed by the increased amounts of VP6 and VP7, which were measured by the semi-quantitative western blot method. In conclusion, hemolymph medium supplementation can be a promising strategy to improve cell viability and productivity of recombinantprotein in BEVS/IC system.

Tunel and limited immunophenotypic analysis of apoptosis in paucibacillary leprosy lesions

Some mycobacterial infections, such as tuberculosis, are characterized by apoptosis in infected or by-stander mononuclear immune cells. For localized (paucibacillary, PB) and diseminated (multibacillary, MB) leprosy, characterized by polarized Thl-like vs, Th2-like immune responses, respectivelly little is known about lesional apoptosis. We analyzed sections of paraffin-embedded, untreated leprosy lesions from 21 patients by an indirect immunofluorescent terminal deoxynucleotide-transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay. Some TUNEL (+) PB sections were then reacted with phycoerythein-conjugated (red)antibodies against T cells, monocytes, or antigen-presenting (Langerhans) cells. TUNEL (+) bodies were detected in 9 of 16 PB lesions (56%) and in 1 of 5 MB lesions (20%). Some TUNELL (+) bodies in PB disease were CD3+ (T cell), as well as CD4+ (T-helper) or cd8+ (T-cytotoxic) Apoptosis characterizes PB and MB leprosy lesions and may be more freqeunt in PB disease. In PB disease, some TUNEL (+) bodies may derive from T cells

Induction of apoptosis in monocytes by Mycobacterium leprae in vitro: a possible role for tumour necrosis factor-alpha

A diverse range of infectious organisms, including mycobacteria, have been reported to induce cell death in vivo and in vitro. Although morphological features of apoptosis have been identified in leprosy lesions, it has not yet been determined whether Mycobacterium leprae modulates programmed cell death. For that purpose, peripheral blood mononuclear cells obtained from leprosy patients were stimulated with different concentrations of this pathogen. Following analysis by flow cytometry on 7AAD/CD14+ cells, it was observed that M. leprae induced apoptosis of monocyte-derived macrophages in a dose-dependent manner in both leprosy patients and healthy individuals, but still with lower efficiency as compared to M. tuberculosis. Expression of tumour necrosis factor-alpha (TNF-alpha), Bax-alpha, Bak mRNA and TNF-alpha protein was also detected in these cultures; in addition, an enhancement in the rate of apoptotic cells (and of TNF-alpha release) was noted when interferon-gamma was added to the wells. On the other hand, incubation of the cells with pentoxifylline impaired mycobacterium-induced cell death, the secretion of TNF-alpha, and gene expression in vitro. In addition, diminished bacterial entry decreased both TNF-alpha levels and the death of CD14+ cells, albeit to a different extent. When investigating leprosy reactions, an enhanced rate of spontaneous apoptosis was detected as compared to the unreactive lepromatous patients. The results demonstrated that M. leprae can lead to apoptosis of macrophages through a mechanism that could be at least partially related to the expression of pro-apoptotic members of the Bcl-2 protein family and of TNF-alpha. Moreover, while phagocytosis may be necessary, it seems not to be crucial to the induction of cell death by the mycobacteria.