Systemic Immunosuppressive Effects Research Articles

Transient Inhibition of Translation Improves Cardiac Function After Ischemia/Reperfusion by Attenuating the Inflammatory Response.

The myocardium adapts to ischemia/reperfusion (I/R) by changes in gene expression, determining the cardiac response to reperfusion. mRNA translation is a key component of gene expression. It is largely unknown how regulation of mRNA translation contributes to cardiac gene expression and inflammation in response to reperfusion and whether it can be targeted to mitigate I/R injury. To examine translation and its impact on gene expression in response to I/R, we measured protein synthesis after reperfusion in vitro and in vivo. Underlying mechanisms of translational control were examined by pharmacological and genetic targeting of translation initiation in mice. Cell type-specific ribosome profiling was performed in mice that had been subjected to I/R to determine the impact of mRNA translation on the regulation of gene expression in cardiomyocytes. Translational regulation of inflammation was studied by quantification of immune cell infiltration, inflammatory gene expression, and cardiac function after short-term inhibition of translation initiation. Reperfusion induced a rapid recovery of translational activity that exceeds baseline levels in the infarct and border zone and is mediated by translation initiation through the mTORC1 (mechanistic target of rapamycin complex 1)-4EBP1 (eIF4E-binding protein 1)-eIF (eukaryotic initiation factor) 4F axis. Cardiomyocyte-specific ribosome profiling identified that I/R increased translation of mRNA networks associated with cardiac inflammation and cell infiltration. Short-term inhibition of the mTORC1-4EBP1-eIF4F axis decreased the expression of proinflammatory cytokines such as Ccl2 (C-C motif chemokine ligand 2) of border zone cardiomyocytes, thereby attenuating Ly6Chi monocyte infiltration and myocardial inflammation. In addition, we identified a systemic immunosuppressive effect of eIF4F translation inhibitors on circulating monocytes, directly inhibiting monocyte infiltration. Short-term pharmacological inhibition of eIF4F complex formation by 4EGI-1 or rapamycin attenuated translation, reduced infarct size, and improved cardiac function after myocardial infarction. Global protein synthesis is inhibited during ischemia and shortly after reperfusion, followed by a recovery of protein synthesis that exceeds baseline levels in the border and infarct zones. Activation of mRNA translation after reperfusion is driven by mTORC1/eIF4F-mediated regulation of initiation and mediates an mRNA network that controls inflammation and monocyte infiltration to the myocardium. Transient inhibition of the mTORC1-/eIF4F axis inhibits translation and attenuates Ly6Chi monocyte infiltration by inhibiting a proinflammatory response at the site of injury and of circulating monocytes.

Lupus Nephritis: Immune Cells and the Kidney Microenvironment.

Lupus nephritis (LN) is the most common major organ manifestation of the autoimmune disease SLE (lupus), with 10% of those afflicted progressing to ESKD. The kidney in LN is characterized by a significant immune infiltrate and proinflammatory cytokine milieu that affects intrinsic renal cells and is, in part, responsible for the tissue damage observed in LN. It is now increasingly appreciated that LN is not due to unidirectional immune cell activation with subsequent kidney damage. Rather, the kidney microenvironment influences the recruitment, survival, differentiation, and activation of immune cells, which, in turn, modify kidney cell function. This review covers how the biochemical environment of the kidney ( i.e ., low oxygen tension and hypertonicity) and unique kidney cell types affect the intrarenal immune cells in LN. The pathways used by intrinsic renal cells to interact with immune cells, such as antigen presentation and cytokine production, are discussed in detail. An understanding of these mechanisms can lead to the design of more kidney-targeted treatments and the avoidance of systemic immunosuppressive effects and may represent the next frontier of LN therapies.

Radiation Therapy Generates Release of Microvesicle Particles in Keratinocytes

Ionizing radiation (IR) exerts both tissue and systemic effects. However, the exact mechanism by which radiation therapy to skin results in local and systemic effects is incompletely defined. Previously our group has reported that IR of tumors results in the generation of the lipid mediator Platelet-activating factor (PAF) which resulted in systemic immunosuppressive effects via activation of regulatory T cells. Since PAF acting on the PAF receptor (PAFR) has been demonstrated to generate high levels of subcellular microvesicle particles (100-1000nm; MVP), and MVP are known to be able to signal systemically, the current studies seek to define whether IR of keratinocyte cells generates MVP, and to define the role of the PAFR in this process. Thus, we examine MVP release in the human keratinocyte cell line HaCaT. Moreover, the PAFR-dependency of IR-generated MVP is assessed by use of PAFR-positive KBP and PAFR-negative KBM cells. HaCaT cells (human keratinocytes), KBM cells (PAFR-negative), and KBP cells (PAFR-positive) were grown in 10cm dishes and treated with IR at either no treatment 0 Gy (NT), 4 Gy and 10 Gy. IR was delivered utilizing a technology company's medical linear accelerator radiotherapy system set up with dosimetry verified by nanodot optical stimulated luminescence (Landauer, Glenwood, IL). Some cell lines were treated with PAFR agonist N-methyl carbamoyl PAF (CPAF) and a phorbol ester TPA, known inducers of MVP release. A set of cells were treated with only 90% DMSO/10% ethanol vehicle in HBSS with BSA. After treatments, cells were incubated for 4 hours prior to extraction of MVPs. MVPs were isolated through centrifuging at 2000G for 20, supernatant was collected, transferred into different tubes, and centrifuged at 20,000 G for 70 mins. MVP was detected using a NanoSight NS300 instrument. MVP concentrations were recorded, and the data was statistically analyzed using Student's t-test (JMP, Cary, NC). IR treatment of HaCaT cells at various fluences exhibited statistically significant increases in MVP generation when compared to NT. Of note, 4 Gy resulted in the most fluence for MVP release but was not significant. IR treatment of KB cells resulted in MVP release in both KBM and KBP cells at both 4 and 10Gy. Augmented levels of MVP release were noted in KBP over KBM cells with any IR dose suggesting that the presence of the PAFR is involved in MVP release. Testing of inhibitors of the MVP generating enzyme acid sphingomyelinase (aSMase) also revealed involvement of this lipid metabolizing enzyme. The present studies indicate that RT can generates MVP production in epithelial cells. The mechanism for IR-generated MVP appears to involve aSMase and the PAFR. Target cell MVP release may provide a mechanism for RT effects, including the release of cytokines that influence systemic and local inflammation. Elucidation of this novel pathway may provide insights into IR effects on skin along with new therapeutic strategies.

The Effect of Inhaled Ciclesonide Treatment on Systemic Markers of Immune Function in Horses

The use of dexamethasone to control equine asthma is a common and effective treatment. Although short-term systemic dexamethasone treatment has not been shown to induce systemic immunosuppression in the horse, the goal of this study was to determine whether inhaled ciclesonide, an FDA-approved drug for the treatment of equine asthma, exerts any systemic immunosuppressive effects when compared to dexamethasone-treated and untreated horses. Eighteen light, mixed breed horses, ranging in age from 3 to 8 years of age, were used for this study and randomly assigned to one of three treatment groups: (1) nontreated controls, (2) ciclesonide treatment, or (3) dexamethasone treatment. Blood was collected daily for steady-state messenger RNA (mRNA) analysis, as well as at Days 0, 5, 10, and 15 of treatment for in vitro stimulation with Concanavalin A (ConA). Messenger RNA relative quantities were determined using RT-qPCR for select genes. Two-way, repeated measures analysis of variance was used to analyze qPCR data and results considered significant at P < .05. There were significant decreases in the steady-state, whole-blood expression of granzyme B and interferon-γ due to dexamethasone treatment, when compared to the nontreated control group. Within ConA-stimulated samples, there remained a suppressive effect of dexamethasone treatment on granzyme B expression compared to nontreated control horses. Similar effects were not noted in the ciclesonide-treated horses. Significant effects of ciclesonide treatment on markers of immune function were not noted in this study, suggesting a low risk for immunosuppression with inhaled ciclesonide treatment.

Low responsiveness of peripheral lymphocytes in extraparenchymal neurocysticercosis

The morbidity and mortality of extraparenchymal neurocysticercosis (EP-NC) remain high and effectiveness of current medical treatment is suboptimal. Various factors have been implicated in the severity of EP-NC and in the poor response to treatment, but the possible role of host immune and endocrine systems has not yet been examined thoroughly. 42 participants with EP-NC before receiving standard treatment and 25 healthy controls were included in the study. Treatment response was assessed by comparing pre/post treatment parasite volumes from 3D MRI. Prior to treatment among participants with EP-NC, specific stimulation induced an increased specific proliferative response accompanied by a significant increase in IL-4, NK, NKT, Bregs and Tregs cells, whereas in healthy controls, specific stimulation induced a significant increase in IL-1β, IL-5, CCL5, IL-6, TNF-α, NK and Bregs cells. Significant differences between participants with EP-NC and healthy controls in the specific inflammatory response were observed. Participants with EP-NC prior to treatment had significantly weaker responses of proinflammatory cytokines (IL-6, TNF-α) and NK cells, and stronger IL-4 response. Anthelmintic treatment did not promote significant peripheral immunological changes at any time, although inflammation was sustained in the cerebrospinal fluid. Serum estradiol concentration significantly decreased after anthelmintic treatment among males, and cortisol correlated negatively with IL-6 and positively with IFN-γ levels. No pre-treatment immunologic or endocrinologic parameters were significantly associated with response to treatment. Prior to anthelmintic treatment, EP-NC was characterized by low lymphocyte reactivity accompanied by a regulatory response, which may be involved in the lack of peripheral immunological changes during and after treatment, although a central inflammatory response was present. This weak specific peripheral response could favor the chronicity of the infection and the poor response to treatment. Our findings highlight the need for new anti-inflammatory treatment focused on the central nervous system with less systemic immunosuppressive effects.

Myeloid-derived suppressor cells are associated with impaired Th1 and Th17 responses and severe pulmonary paracoccidioidomycosis which is reversed by anti-Gr1 therapy.

Previous studies on paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in Latin America, revealed that host immunity is tightly regulated by several suppressive mechanisms mediated by tolerogenic plasmacytoid dendritic cells, the enzyme 2,3 indoleamine dioxygenase (IDO-1), and regulatory T-cells (Tregs). IDO-1 orchestrates local and systemic immunosuppressive effects through the recruitment and activation of myeloid-derived suppressor cells (MDSCs), a heterogeneous population of myeloid cells possessing a potent ability to suppress T-cell responses. However, the involvement of MDSCs in PCM remains uninvestigated. The presence, phenotype, and immunosuppressive activity of MDSCs were evaluated at 96h, 2 weeks, and 8 weeks of pulmonary infection in C57BL/6 mice. Disease severity and immune responses were assessed in MDSC-depleted and nondepleted mice using an anti-Gr1 antibody. Both monocytic-like MDSCs (M-MDSCs) and polymorphonuclear-like MDSCs (PMN-MDSCs) massively infiltrated the lungs during Paracoccidioides brasiliensis infection. Partial reduction of MDSC frequency led to a robust Th1/Th17 lymphocyte response, resulting in regressive disease with a reduced fungal burden on target organs, diminishing lung pathology, and reducing mortality ratio compared with control IgG2b-treated mice. The suppressive activity of MDSCs on CD4 and CD8 T-lymphocytes and Th1/Th17 cells was also demonstrated in vitro using coculture experiments. Conversely, adoptive transfer of MDSCs to recipient P. brasiliensis-infected mice resulted in a more severe disease. Taken together, our data showed that the increased influx of MDSCs into the lungs was linked to more severe disease and impaired Th1 and Th17 protective responses. However, protective immunity was rescued by anti-Gr1 treatment, resulting in a less severe disease and controlled tissue pathology. In conclusion, MDSCs have emerged as potential target cells for the adjuvant therapy of PCM.

Targeted delivery of platelet membrane modified extracellular vesicles into atherosclerotic plaque to regress atherosclerosis

Atherosclerosis is a major underlying cause of cardiovascular disease. Although certain success has been achieved in treatment for atherosclerosis, the risk of cardiovascular diseases still remains high. Anti-inflammation therapy was proved to halt atherosclerosis progression, but their clinical application was hindered by the systemic immunosuppressive effect. Since macrophages play a key role in the development of atherosclerosis, targeted delivery of anti-inflammatory therapeutics to lesional macrophages might be an effective therapeutic strategy to resolve localized inflammation while reducing the adverse effects. Mesenchymal stem cells derived extracellular vesicles (MSC-EVs) are believed to possess anti-atherosclerosis effects by reducing inflammation. In this study, we fabricated platelet mimetic MSC-EVs (P-EVs) by decorating EVs with platelets membranes. P-EVs inherited the natural homing ability of platelets to plaques and therapeutic effects of MSC-EVs. When injected into atherosclerotic mice, P-EVs were recruited to injured endothelium, then penetrated into plaques followed with endocytosis by inflammatory macrophages through the interaction between platelet membranes proteins and macrophages surface proteins. Subsequently, P-EVs delivered miRNAs into the cytoplasm of macrophages through lysosomal escape, which attenuated the progression of atherosclerosis eventually by switching the macrophage into anti-inflammatory phenotype, scavenging the overproduced ROS and reducing lipid deposition in lesional macrophages. In general, our study demonstrated the pro-resolving potential of P-EVs for targeted anti-inflammation therapy of atherosclerosis.

Visual Outcomes of Patients With Peripheral Ulcerative Keratitis and the Effect of Immunosuppression-A 6-Year Experience in Queensland, Australia.

Peripheral ulcerative keratitis (PUK) can cause significant ocular morbidity and mortality. This study aimed to review the effects of systemic immunosuppression on visual outcomes. A state-wide, retrospective case series based in Queensland, Australia, was performed. A review of patients who presented with PUK to the major tertiary ophthalmology referral centers between January 2015 and January 2021 was undertaken. Parameters recorded included clinical features at presentation, investigations undertaken, treatment provided, visual outcomes, and mortality outcomes. The effect of immunomodulatory therapy on the change in vision from presentation to the most recent review was analyzed. Twenty-two eyes of 26 patients with PUK (average age 69.81±14.54 years) were included and had a mean follow-up period of 577.73 days. Twelve patients (54.5%) had systemic autoimmune disease, one patient (4.5%) had positive syphilis serology, and nine patients (40.9%) had idiopathic PUK. Eighteen patients (81.8%) were treated with systemic steroids and 10 patients (45.5%) were treated with steroid-sparing immunomodulatory therapy. Average logarithm of the minimum angle of resolution best-corrected visual acuity (BCVA) at presentation and final follow-up were 0.63±0.65 and 0.64±0.82, respectively. Those who were treated with immunomodulatory therapy had a nonstatistically significant improvement in BCVA (-0.10±0.29 with vs. +0.10±0.35 without), and a similar trend was seen for doxycycline (-0.08±0.09 with vs. +0.22±0.49 without). Four of five perforations (80%) were surgically managed. Four patients (18.2%) were deceased. Peripheral ulcerative keratitis poses significant clinical challenges and requires intensive medical treatment, frequently involving systemic immunomodulatory therapy. Surgical treatment is required in a significant minority of cases. Ocular management alongside the use of doxycycline and immunomodulatory therapy in consultation with specialist physicians can optimize visual and systemic outcomes.

Obesity modulates the immune macroenvironment associated with breast cancer development.

Growing evidence demonstrates a strong correlation between obesity and an increased risk of breast cancer, although the mechanisms involved have not been completely elucidated. Some reports have described a crosstalk between adipocytes, cancer cells, and immune cells within the tumor microenvironment, however, it is currently unknown whether obesity can promote tumor growth by inducing systemic alterations of the immune cell homeostasis in peripheral lymphoid organs and adipose tissue. Here, we used the E0771 breast cancer cell line in a mouse model of diet-induced obesity to analyze the immune subpopulations present in the tumors, visceral adipose tissue (VAT), and spleen of lean and obese mice. Our results showed a significant reduction in the frequency of infiltrating CD8+ T cells and a decreased M1/M2 macrophage ratio, indicative of the compromised anti-tumoral immune response reported in obesity. Despite not finding differences in the percentage or numbers of intratumoral Tregs, phenotypic analysis showed that they were enriched in CD39+, PD-1+ and CCR8+ cells, compared to the draining lymph nodes, confirming the highly immunosuppressive profile of infiltrating Tregs reported in established tumors. Analysis of peripheral T lymphocytes showed that tumor development in obese mice was associated to a significant increase in the percentage of peripheral Tregs, which supports the systemic immunosuppressive effect caused by the tumor. Interestingly, evaluation of immune subpopulations in the VAT showed that the characteristic increase in the M1/M2 macrophage ratio reported in obesity, was completely reversed in tumor-bearing mice, resembling the M2-polarized profile found in the microenvironment of the growing tumor. Importantly, VAT Tregs, which are commonly decreased in obese mice, were significantly increased in the presence of breast tumors and displayed significantly higher levels of Foxp3, indicating a regulatory feedback mechanism triggered by tumor growth. Altogether, our results identify a complex reciprocal relationship between adipocytes, immune cells, and the tumor, which may modulate the immune macroenvironment that promotes breast cancer development in obesity.

The systemic immunosuppressive effects of peripheral corticosteroid injections: A narrative review of the evidence in the context of COVID-19.

IntroductionInjected glucocorticoid's (corticosteroids) are commonly used in musculoskeletal practice. The current global COVID‐19 pandemic has increased attention on the potential for locally injected corticosteroids to exert a systemic immunosuppressive effect and the implications this may have in relation to COVID‐19 infection and vaccination.AimThis narrative review summarises the evidence regarding the potential systemic immunosuppressive effects of peripheral corticosteroid injections in relation to the ongoing COVID‐19 pandemic.MethodA narrative review was selected to allow inclusion of evidence related to a diverse range of topics relevant to this subject in order to provide the most comprehensive and clinically relevant guidance for clinicians.Results/discussionCurrent evidence demonstrates that cytotoxic, phagocytic and antigen presenting cells involved in both the innate and adaptive immune responses are suppressed for 48 h post‐injection and messenger cytokines that are integral to immune function are suppressed for over 96 h post‐injection. This potentially reduces an individual's ability to prevent viral infection, limit early viral replication, and delays activation of adaptive immune mechanisms (T and B lymphocytes) and subsequent viral clearance and elimination. The hypothalamic–pituitary–adrenal (HPA) axis can be suppressed for 2–4 weeks or longer following peripheral corticosteroid injections. The role of the HPA axis in immune function is not fully understood, however this could potentially indicate longer lasting immunosuppression.ConclusionsThis review found evidence of suppression of immune cell numbers for the first 48 h post‐injection, cytokines for over 96 h post‐injection and HPA axis suppression lasting for 2–4 weeks or longer. There is currently no evidence that these physiological changes translate into a clinically meaningful increased risk of COVID‐19 infection or related morbidity or mortality, but there is also no persuasive evidence that they do not. This review discusses the implications of the current evidence in relation to shared decision making, informed consent, risk management and COVID‐19 vaccination to provide clinicians with a pragmatic guide to help navigate the current uncertainty regarding the potential immunosuppressive effects of peripheral corticosteroid injections.

111 The Systemic Effects of Intra-Articular Steroid Injections- Should COVID-19 Change Our Practice?

Abstract Aim The COVID-19 pandemic prompted us to review and often suspend services, while patients continue to suffer with painful musculoskeletal conditions. The diagnostic and therapeutic value of intra-articular corticosteroid injections (IACSI) cannot be denied. Current BOA guidelines advise giving the lowest effective dose for inflammatory arthritis and limit use in osteoarthritis to patients with high levels of pain and disability. We aimed to evaluate the literature pertaining to the use of IACSI and the potential systemic immunosuppressive effects. Method We searched Medline, using the terms “systemic effects of intra-articular steroid” and “clinical course of Coronavirus infection in patients with steroid use”, between 1997 and 2020. Results No studies specifically looked at the systemic effects of intra-articular steroids in the presence of COVID-19 infection; however, four studies were identified which concluded that intra-articular steroid injections resulted in sufficient systemic absorption to cause suppression of the hypothalamic-pituitary-adrenal axis and endogenous cortisol production. These effects are dose dependent and are more common in patients with inflammatory joint diseases. A further four RCT’s, including one systematic review, showed that suppressed cortisol concentration was associated with a significant increase in mortality. Conclusions There is a lack of evidence in relation to the use of intra-articular steroids in COVID-19. However, evidence suggests that intra-articular steroids can result in systemic absorption and suppression of endogenous cortisol production thus increasing the potential risk of complications of COVID-19. We therefore support cautious use of low dose steroid injections in patients with inflammatory arthritis, where no alternative treatment is available.

Local Immunomodulatory Strategies to Prevent Allo-Rejection in Transplantation of Insulin-Producing Cells.

Islet transplantation has shown promise as a curative therapy for type 1 diabetes (T1D). However, the side effects of systemic immunosuppression and limited long‐term viability of engrafted islets, together with the scarcity of donor organs, highlight an urgent need for the development of new, improved, and safer cell‐replacement strategies. Induction of local immunotolerance to prevent allo‐rejection against islets and stem cell derived β cells has the potential to improve graft function and broaden the applicability of cellular therapy while minimizing adverse effects of systemic immunosuppression. In this mini review, recent developments in non‐encapsulation, local immunomodulatory approaches for T1D cell replacement therapies, including islet/β cell modification, immunomodulatory biomaterial platforms, and co‐transplantation of immunomodulatory cells are discussed. Key advantages and remaining challenges in translating such technologies to clinical settings are identified. Although many of the studies discussed are preliminary, the growing interest in the field has led to the exploration of new combinatorial strategies involving cellular engineering, immunotherapy, and novel biomaterials. Such interdisciplinary research will undoubtedly accelerate the development of therapies that can benefit the whole T1D population.

Unaltered IL-2 encapsulated in acoustically active lipid microspheres for systemic but targeted microdose delivery to tumor microenvironment.

e14535 Background: In order to take local advantage of exogenous interleukin-2 (IL-2) on effector T-cells within the tumor microenvironment while simultaneously avoiding systemic Treg immunosuppressive effects, microdoses of recombinant human IL-2 (rhIL-2) were encapsulated in gas-filled lipid microspheres (eIL-2), then activated with ultrasound. This novel therapeutic agent (eIL-2) was selectively delivered to the tumor via sonoporation and its anti-tumor effects were determined alone and in combination with PD-1 blockade. Methods: In an MC38 colon cancer model, jugular button catheters (Instech) were surgically implanted in a total of 56 animals (8 animals per arm) prior to tumor inoculation to facilitate repeatable IV injection of both anti-PD-1 (RMP1-14; BioXCell) and microspheres. Imagent perflexane lipid microspheres were incubated with rhIL-2 and the high concentration infranatant was separated, discarded, and replaced with sterile saline to resuspend microspheres to formulate eIL-2 on-site. Tumor-bearing mice were dosed on Days 1, 4, 8, and 12. Ultrasound (US) settings used were 2.2 MHz frequency, and 0.339 mechanical index (MI) during insonation. Once every 10 seconds a microbubble destruct pulse of 1.304 MI lasting 1,100 milliseconds was applied. Total insonation time was 5 minutes using a commercial ultrasound scanner (Mindray TE7) operating within diagnostically safe exposure limits. Study groups included Group 1: no treatment; Group 2: aPD-1, 3 mg/kg; Group 3: aPD-1, 3 mg/kg, Imagent + US; Group 4: Free rhIL-2, 10,000 IU (0.61μg)/animal; Group 5: eIL-2, approximately 0.2 μg encapsulated/animal; Group 6: Free rhIL-2, 10,000 IU (0.61μg)/animal, aPD-1, 3 mg/kg; Group 7: eIL-2, approximately 0.1 μg encapsulated/animal, aPD-1, 3 mg/kg. Results: The anti-PD-1 dose of 3 mg/kg demonstrated an expected tumor growth inhibition over control of -38.2% on Day 6, -35.6% on Day 8 and -30.3% on Day 12. Adding eIL-2 + ultrasound external stimuli approximately doubled the tumor inhibition effect of RMP1-14 to -68.1% on Day 6, -69.2% on Day 8 and -62.0% on Day 12. We also analyzed cytokine levels in the peripheral blood (Day 12) using a multiplex ELISA and observed elevated levels of pro-inflammatory cytokines including IFN-g, IL-12, and IL-1a, which likely serve to enhance anti-tumor immunity. IL-15 was also increased following treatment, which supports effector T cell survival. Conclusions: Using a novel form of recombinant human interleukin-2 encapsulated within a gas-filled lipid microsphere, we demonstrated that ultrasound-activated local delivery via sonoporation plus systemic PD-1 blockade led to improved tumor control and increased expression of pro-inflammatory cytokines. This novel approach enhances the efficacy of checkpoint blockade for the treatment of solid tumors. Further experiments are underway to interrogate mechanisms of action.

Autoreactive Peripheral Blood T Helper Cell Responses in Bullous Pemphigoid and Elderly Patients With Pruritic Disorders.

Bullous pemphigoid (BP) is a prototypic autoimmune disorder of the elderly, characterized by serum IgG autoantibodies, namely anti-BP180 and anti-BP230, directed against components of the basal membrane zone that lead to sub-epidermal loss of adhesion. Pruritus may be indicative of a pre-clinical stage of BP, since a subset of these patients shows serum IgG autoantibodies against BP230 and/or BP180 while chronic pruritus is increasingly common in the elderly population and is associated with a variety of dermatoses. Clinical and experimental evidence further suggests that pruritus of the elderly may be linked to autoimmunity with loss of self-tolerance against cutaneous autoantigens. Thus, the objective of this study was to determine autoreactive T cell responses against BP180 in elderly patients in comparison to patients with BP. A total of 22 elderly patients with pruritic disorders, 34 patients with bullous or non-bullous BP and 34 age-matched healthy controls were included in this study. The level of anti-BP180 and anti-BP230 IgG serum autoantibodies, Bullous Pemphigoid Disease Area Index (BPDAI), and pruritus severity were assessed for all patients and controls. For characterization of the autoreactive T cell response, peripheral blood mononuclear cells were stimulated ex vivo with recombinant BP180 proteins (NH2- and COOH-terminal domains) and the frequencies of BP180-specific T cells producing interferon-γ, interleukin (IL)-5 or IL-17 were subsequently determined by ELISpot assay. Patients with BP showed a mixed Th1/Th2 response against BP180 while autoreactive Th1 cells were identified in a minor subset of elderly patients with pruritic disorders. Furthermore, our T cell characterization revealed that therapeutic application of topical clobetasol propionate ointment in BP patients significantly reduced peripheral blood BP180-specific T cells, along with clinically improved symptoms, strongly suggesting a systemic immunosuppressive effect of this treatment.

The involvement of chronic persistent viral infection to various diseases of the oral cavity

Relevance. According to the literature all over the world, there is a tendency to reduce immunological reactivity in humans, this is facilitated by the presence of chronic persistent herpes viral infection. Herpes infection has systemic immunosuppressive effects of the infection on the human body, and also highlighted the role of the virus in a slow occurrence of combined pathology of internal organs and infectious and inflammatory diseases of the oral tissues and periodontium. High interest of specialists to this problem сaused by the necessity of new methods of complex treatment polymorbidity human pathology. Purpose – to assess the degree of involvement of chronic cytomegalovirus persistence in a number of dental diseases.Materials and methods. In 67 patients dental surgery underwent surgery removal of benign tumors of the soft tissues of the oral cavity, periodontium and jaws, had a clinical blood analysis, blood testing for serological signs of chronic persistence of cytomegalovirus infection (antibodies to CMV Ig G (anti CMV IgG), PCR for CMV in blood and saliva, and also studied the cellular composition of blood immunogram. The age of patients averaged 46 years. Рatients were divided according to the nosological principle into 4 groups. The first group consisted of patients with periapical foci of chronic odontogenic inflammation and radicular cysts of the jaws. The second group consisted of persons with oral fibroids of different localization. The third group is patients with retention cysts of small salivary glands of the oral mucosa. The fourth group – patients with poligamy various locations. All operations are performed outside the phase of acute inflammation. The material obtained after the operation underwent histological examination.Results. Serological signs of chronic persistence of cytomegalovirus infection were revealed in all examined patients, the level of anti CMV Ig was 225 ± 25 U / ml (at the rate of 0.00-0.50 U / ml) (p 0.01). Also, all patients showed lymphocytosis of blood and this corresponded to the same type of changes in the cellular composition of the immunogram with a decrease in the quantitative parameters of B-lymphocytes (CD19+ CD3- ), true natural "killers" (NK-cells) (CD3- CD56+ CD45+ ), NK-cells cytokine-producing (CD3- CD16+ Cd56brightcd45+ ), NK-cells cytolytic (CD3- CD16+ (orhigh) sd56dimcd45+ ). The results of the histological study showed that focal mononuclear and lymphohistiocytic cell infiltration with giant cells with large nuclei are more often detected in areas of the oral mucosa in all patients with radical and retention cysts.Conclusion. The Obtained results demonstrate that in patients regardless of surgical dental diagnosis, chronic persistence of cytomegalovirus with the same type of hematological, immunological abnormalities was revealed. In areas of the oral mucosa with retention cysts of small salivary glands and with radicular cysts, focal lymphohistiocytic and mononuclear cell infiltration with giant cells with large nuclei was revealed.

Current Role of Anti-Integrin Therapy in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory intestinal disorder with multifactorial etiology. Management of IBD is divided into conventional treatment and new treatment with biologic agents. The first biologic agents used for IBD was tumor necrosis factor (TNF)-inhibitor. However, TNF-inhibitor as a biologic agent has several limitations such as low rate of clinical response and systemic immunosuppressive side effects. Anti-integrin is a recently developed biologic agent which selectively inhibits leukocyte trafficking towards site of inflammation. The inhibition is caused by blocking the actions of integrin, a cell adhesion molecules (CAMs) that is necessary for leukocyte trafficking and leukocytes express specific integrin receptors for specific organs. Therefore, use of gut-specific anti-integrin agents in IBD can selectively prevent influx of leukocytes into the intestine to reduce inflammation without reducing immune function in other locations. As a result, gut-specific anti-integrin is hypothesized to have lower risk of infections and lower risk of malignancy than TNF-inhibitor while maintaining high therapeutic benefits, making anti-integrin a promising therapy for IBD in the future.

Adipose-derived stromal cell therapy combined with a short course nonmyeloablative conditioning promotes long-term graft tolerance in vascularized composite allotransplantation.

The risks of chronic immunosuppression limit the utility of vascularized composite allotransplantation (VCA) as a reconstructive option in complex tissue defects. We evaluated a novel, clinically translatable, radiation-free conditioning protocol that combines anti-lymphocyte serum (ALS), tacrolimus, and cytotoxic T-lymphocyte-associated protein 4 immunoglobulin (CTLA4-Ig) with adipose-derived stromal cells (ASCs) to allow VCA survival without long-term systemic immunosuppression. Full-mismatched rat hind-limb-transplant recipients received tacrolimus (0.5mg/kg) for 14days and were assigned to 4 groups: controls (CTRL) received no conditioning; ASC-group received CTLA4-Ig (10mg/kg body weight i.p. postoperative day [POD] 2, 4, 7) and donor ASCs (1×106 iv, POD 2, 4, 7, 15, 28); the ASC-cyclophosphamide (CYP)-group received CTLA4-Ig, ASC plus cyclophosphamide (50mg/kg ip, POD 3); the ASC-ALS-group received CTLA4-Ig, ASCs plus ALS (500µL ip, POD 1, 5). Banff grade III or 120days were endpoints. ASCs suppressed alloresponse in vitro. Median rejection-free VCA survival was 28days in CTRL (n=7), 34 in ASC (n=6), and 27.5 in ASC-CYP (n=4). In contrast, ASC-ALS achieved significantly longer, rejection-free VCA survival in 6/7 animals (86%), with persistent mixed donor-cell chimerism, and elevated systemic and allograft skin Tregs , with no signs of acute cellular rejection. Taken together, a regimen comprised of short-course tacrolimus, repeated CTLA4-Ig and ASC administration, combined with ALS, promotes long-term VCA survival without chronic immunosuppression.

Inhaled Cyclosporine-Based Immunosuppression Regimen for Lung Transplant Associated Malignancy

Purpose The clinical outcome of lung transplantation has improved markedly over the last three decades after the introduction of calcineurin inhibitors. However, one of its main disadvantages appears to be calcineurin-related adverse effects including malignancy, infection and nephrotoxicity. We sought strategies to maintain lung function while decreasing the effects of systemic immunosuppression for patients who develop cancer after lung transplantation. Methods Fourteen patients were treated with propylene glycol inhaled cyclosporine at the University of Maryland Medical Center (UMMC) between February 2013 and October 2017 after cancer diagnosis, at the discretion of their lung transplant physician on a compassionate use basis. The cancers that occurred were metastatic lung (n=1), extensive/metastatic skin cancer (n=10), extensive PTLD (n=3). Results FEV1 remained stable over the twelve-month study intervals; baseline median 2.33 L/sec (IQR 1.75-2.60, n=14); three month 2.21 (1.70-2.51, n=14); six month 2.44 (IQR 1.97-2.58, n=11); twelve month 2.40 (IQR 1.98-2.88, n=9); p=0.59. CNI exposure were reduced from 6.8 (IQR 2.7-8.0) to 4.1 (IQR 3.4-4.6) at 12 month after starting inhaled cyclosporine. Cr remained stable during the follow-up with baseline 1.25 mg/dl (1.00-1.26), three month 1.40mg/dl (1.07-1.85), six month 1.34mg/dl (1.08-1.72) and twelve months 1.50mg/dl (1.33-1.62) after inhaled cyclosporine initiation; p=0.18. Conclusion Inhaled cyclosporine-based immunosuppression regimen is associated with stability of lung function in lung transplant recipients receiving reduced immunosuppression after diagnosis of malignancy

Enhanced Drug Delivery to the Skin Using Liposomes.

Background:Enhancing drug delivery to the skin has importance in many therapeutic strategies. In particular, the outcome in vascularized composite allotransplantation mainly depends on systemic immunosuppression to prevent and treat episodes of transplant rejection. However, the side effects of systemic immunosuppression may introduce substantial risk to the patient and are weighed against the expected benefits. Successful enhancement of delivery of immunosuppressive agents to the most immunogenic tissues would allow for a reduction in systemic doses, thereby minimizing side effects. Nanoparticle-assisted transport by low temperature–sensitive liposomes (LTSLs) has shown some benefit in anticancer therapy. Our goal was to test whether delivery of a marker agent to the skin could be selectively enhanced.Methods:In an in vivo model, LTSLs containing doxorubicin (dox) as a marker were administered intravenously to rats that were exposed locally to mild hyperthermia. Skin samples of the hyperthermia treated hind limb were compared with skin of the contralateral normothermia hind limb. Tissue content of dox was quantified both via high-performance liquid chromatography and via histology in skin and liver.Results:The concentration of dox in hyperthermia-treated skin was significantly elevated over both normothermic skin and liver. (P < 0.02).Conclusions:We show here that delivery of therapeutics to the skin can be targeted and enhanced using LTSLs. Targeting drug delivery with this method may reduce the systemic toxicity seen in a systemic free-drug administration. Development of more hydrophilic immunosuppressants in the future would increase the applicability of this system in the treatment of rejection reactions in vascularized composite allotransplantation. The treatment of other skin condition might be another potential application.

Platelet-Activating Factor-Induced Reduction in Contact Hypersensitivity Responses Is Mediated by Mast Cells via Cyclooxygenase-2-Dependent Mechanisms.

Platelet-activating factor (PAF) stimulates numerous cell types via activation of the G protein-coupled PAF receptor (PAFR). PAFR activation not only induces acute proinflammatory responses, but it also induces delayed systemic immunosuppressive effects by modulating host immunity. Although enzymatic synthesis and degradation of PAF are tightly regulated, oxidative stressors, such as UVB, chemotherapy, and cigarette smoke, can generate PAF and PAF-like molecules in an unregulated fashion via the oxidation of membrane phospholipids. Recent studies have demonstrated the relevance of the mast cell (MC) PAFR in PAFR-induced systemic immunosuppression. The current study was designed to determine the exact mechanisms and mediators involved in MC PAFR-mediated systemic immunosuppression. By using a contact hypersensitivity model, the MC PAFR was not only found to be necessary, but also sufficient to mediate the immunosuppressive effects of systemic PAF. Furthermore, activation of the MC PAFR induces MC-derived histamine and PGE2 release. Importantly, PAFR-mediated systemic immunosuppression was defective in mice that lacked MCs, or in MC-deficient mice transplanted with histidine decarboxylase- or cyclooxygenase-2-deficient MCs. Lastly, it was found that PGs could modulate MC migration to draining lymph nodes. These results support the hypothesis that MC PAFR activation promotes the immunosuppressive effects of PAF in part through histamine- and PGE2-dependent mechanisms.