Annexin A5 is essential for PKCθ translocation during T-cell activation.

T-cell activation is a critical part of the adaptive immune system, enabling responses to foreign cells and external stimulus. In this process, T-cell antigen receptor (TCR) activation stimulates translocation of the downstream kinase PKCθ to the membrane, leading to NF-κB activation and thus transcription of relevant genes. However, the details of how PKCθ is recruited to the membrane remain enigmatic. It is known that annexin A5 (ANXA5), a calcium-dependent membrane-binding protein, has been reported to mediate PKCδ activation by interaction with PKCδ, a homologue of PKCθ, which implicates a potential role of ANXA5 involved in PKCθ signaling. Here we demonstrate that ANXA5 does play a critical role in the recruitment of PKCθ to the membrane during T-cell activation. ANXA5 knockout in Jurkat T cells substantially inhibited the membrane translocation of PKCθ upon TCR engagement and blocked the recruitment of CARMA1-BCL10-MALT1 signalosome, which provides a platform for the catalytic activation of IKKs and subsequent activation of canonical NF-κB signaling in activated T cells. As a result, NF-κB activation was impaired in ANXA5-KO T cells. T-cell activation was also suppressed by ANAX5 knockdown in primary T cells. These results demonstrated a novel role of ANXA5 in PKC translocation and PKC signaling during T-cell activation.

Programmed self-assembly of peptide-major histocompatibility complex for antigen-specific immune modulation.

A technology to prime desired populations of T cells in the body-particularly those that possess low avidity against target antigen-would pave the way for the design of new types of vaccination for intractable infectious diseases or cancer. Here, we report such a technology based on positive feedback-driven, programmed self-assembly of peptide-major histocompatibility complex (pMHC) directly on the membrane of cognate T cells. Our design capitalizes on the unique features of the protein annexin V (ANXA5), which-in a concerted and synergistic manner-couples the early onset of TCR signaling by cognate pMHC with a surge in pMHC-TCR affinity, with repeated pMHC encounters, and with widespread TCR cross-linking. In our system, ANXA5 is linked to pMHC and firmly engages the plasma membrane of cognate T cells upon (and only upon) the early onset of TCR signaling. ANXA5, in turn, exerts a mechanical force that stabilizes interactions at the TCR-pMHC interface and facilitates repeated, serial pMHC encounters. Furthermore, ANXA5 quickly arranges into uniform 2D matrices, thereby prompting TCR cross-linking. Fusion of ANXA5 to pMHC augments lymphocyte activation by several orders of magnitude (>1,000-fold), bypasses the need for costimulation, and breaks tolerance against a model self-antigen in vivo. Our study opens the door to the application of synthetic, feedback-driven self-assembly platforms in immune modulation.

Annexin V expression on CD4+ T cells with regulatory function.

Regulatory T (Treg) cells induce immunologic tolerance by suppressing effector functions of conventional lymphocytes in the periphery. On the other hand, immune silencing is mediated by recognition of phosphatidylserine (PS) on apoptotic cells by phagocytes. Here we describe expression of the PS-binding protein Annexin V (ANXA5) in CD4+  CD25hi Treg cells at the mRNA and protein levels. CD4+  ANXA5+ T cells constitute about 0·1%-0·6% of peripheral blood CD3+ T cells, exhibit co-expression of several Treg markers, such as Forkhead box P3, programmed cell death protein-1, cytotoxic T-lymphocyte antigen-4 and CD38. In vitro, ANXA5+ Treg cells showed enhanced adhesion to PS+ endothelial cells. Stimulated by anti-CD3 and PS+ syngeneic antigen-presenting cells CD4+  ANXA5+ T cells expanded in the absence of exogenous interleukin-2. CD4+  ANXA5+ T cells suppressed CD4+  ANXA5- T-cell proliferation and mammalian target of rapamycin phosphorylation, partially dependent on cell contact. CD4+  ANXA5+ T-cell-mediated suppression was allo-specific and accompanied by an increased production of anti-inflammatory mediators. In vivo, using a model of delayed type hypersensitivity, murine CD4+  ANXA5+ T cells inhibited T helper type 1 responses. In conclusion, we report for the first time expression of ANXA5 on a subset of Treg cells that might bridge classical regulatory Treg function with immune silencing.

HIV-1 infection modulates IL-24 expression which contributes to cell apoptosis in vitro.

Although interleukin-24 (IL-24) has been extensively explored in the immunopathologies of autoimmune diseases, neoplasms, and infections, its role in HIV-1 infection has not been thoroughly elucidated to date. Therefore, the objective of this study was to evaluate the gene and protein expressions of IL-24 at the initial moments of HIV infection in PBMCs. Due to the pro-apoptotic role of IL-24, we evaluated the protein expression of caspase-3, as well as Annexin V/Propidium Iodide flow cytometry and phosphorylation of ERK, which may induce an apoptotic signal block when phosphorylated. The results of this study demonstrated that HIV-1 infection had an impact on the gene and protein expressions of IL-24 and ERK. Annexin V/Propidium Iodide assay demonstrated decrease in the mechanisms of apoptosis in infected cells after incubation of IL-24 neutralizing antibody. Studies on how HIV-1 regulates IL-24 expression may play a role in characterizing viral persistence mechanisms and designing antiretroviral strategies.

Association of silent infarcts in sickle cell anemia with decreased annexin A5 resistance.

BACKGROUND: Sickle cell anemia (SCA) is characterized by abnormally shaped, adhesive RBCs that interact with white blood cells and the endothelium, leading to chronic hemolysis, vasculopathy and a prothrombotic state. About 10% of subjects with a thrombotic event in the general population will have an associated antiphospholipid (aPL) antibody. One proposed mechanism for the thrombophilic nature of aPL antibodies is the disruption of the potent anticoagulant annexin A5 or Annexin A5 resistance (A5R). We designed a pilot study assessing the presence of aPL antibodies and disruption of A5R in pediatric sickle cell subjects. METHODS: 39 subjects with SCA participated in this study. A5R, DRVVT, anti-ß2GP1, anti-ß2GP1, anti-phosphatidylserine and anti-cardiolipin antibody assays were performed. RESULTS: There was a high prevalence of abnormal A5R despite a low prevalence of antiphospholipid antibodies. Multivariate logistic regression analyses showed an association with silent infarcts (p=0.015), lower hemoglobin (p=0.037), older age (p=0.047) and abnormal A5R. CONCLUSION: We report an association between annexin A5 resistance and presence of silent infarct, low hemoglobin, and older age in a subgroup of SCA subjects. A potential role for perturbed A5R in the pathophysiology of SCA needs to be evaluated further.

Interleukin 15 activates Akt to protect astrocytes from oxygen glucose deprivation-induced cell death.

Astrocytes play a pivotal role in neuronal survival under the condition of post-ischemic brain inflammation, but the relevant astrocyte-derived mediators of ischemic brain injury remain to be defined. IL-15 supports survival of multiple lymphocyte lineages in the peripheral immune system, but the role of IL-15 in inflammatory disease of the central nervous system is not well defined. Recent research has shown an increase of IL-15-expressing astrocytes in the ischemic brain. Since astrocytes promote neuron survival under cerebral ischemia by buffering excess extracellular glutamate and producing growth factors, recovery of astrocyte function could be of benefit for stroke therapy. Here, we report that IL-15 is the pro-survival cytokine that prevents astrocyte death from oxygen glucose deprivation (OGD)-induced damage. Astrocytes up-regulate expression of the IL-15/IL-15Rα complex under OGD, whereas OGD down-regulates the levels of pSTAT5 and pAkt in astrocytes. IL-15 treatment ameliorates the decline of pAkt, decreases the percentage of annexin V+ cells, inhibits the activation of caspase-3, and activates the Akt pathway to promote astrocyte survival in response to OGD. We further identified that activation of Akt, but not PKCα/ßI, is essential for astrocyte survival under OGD. Taken together, this study reveals the function of IL-15 in astrocyte survival via Akt phosphorylation in response to OGD-induced damage.

The tolerogenic function of annexins on apoptotic cells is mediated by the annexin core domain.

Immunological tolerance is constantly being maintained in the periphery by dendritic cells processing material from apoptotic cells (ACs) in the steady-state. Although research has focused on the uptake of ACs by phagocytes, tolerogenic signals exposed by the ACs are much less well defined. In this article, we show that the annexin (Anx) family members AnxA5 and AnxA13 translocate to the surface of ACs to function as redundant tolerogenic signals in vitro and in vivo. Exposure of bone marrow-derived dendritic cells to AnxA5 or AnxA13 in vitro resulted in the inhibition of both proinflammatory cytokine secretion and the upregulation of costimulatory molecules upon TLR stimulation. The highly conserved Anx core domain was sufficient to mediate these effects, whereas recognition by N-formyl peptide receptor family members was dispensable. In vivo, coinjection of OVA-expressing and Anx-expressing ACs prevented induction of Ag-specific CD8(+) T cells. Moreover, mice immunized with Anx-expressing ACs became refractory to an antigenic challenge. These results suggest that several Anxs contribute to AC-induced suppression of dendritic cell activation. Therefore, manipulating Anx-mediated immunosuppression may prove beneficial for patients with cancer or autoimmune diseases and chronic inflammatory disorders.

Dengue NS1 antigen contributes to disease severity by inducing interleukin (IL)-10 by monocytes.

Both dengue NS1 antigen and serum interleukin (IL)-10 levels have been shown to associate with severe clinical disease in acute dengue infection, and IL-10 has also been shown to suppress dengue-specific T cell responses. Therefore, we proceeded to investigate the mechanisms by which dengue NS1 contributes to disease pathogenesis and if it is associated with altered IL-10 production. Serum IL-10 and dengue NS1 antigen levels were assessed serially in 36 adult Sri Lankan individuals with acute dengue infection. We found that the serum IL-10 levels correlated positively with dengue NS1 antigen levels (Spearman's r = 0·47, P < 0·0001), and NS1 also correlated with annexin V expression by T cells in acute dengue (Spearman's r = 0·63, P = 0·001). However, NS1 levels did not associate with the functionality of T cell responses or with expression of co-stimulatory molecules. Therefore, we further assessed the effect of dengue NS1 on monocytes and T cells by co-culturing primary monocytes and peripheral blood mononuclear cells (PBMC), with varying concentrations of NS1 for up to 96 h. Monocytes co-cultured with NS1 produced high levels of IL-10, with the highest levels seen at 24 h, and then declined gradually. Therefore, our data show that dengue NS1 appears to contribute to pathogenesis of dengue infection by inducing IL-10 production by monocytes.

IgA enhances NETosis and release of neutrophil extracellular traps by polymorphonuclear cells via Fcα receptor I.

Polymorphonuclear cells (neutrophils) are the first cells that arrive at sites of infections. According to the current dogma, they are involved in eliminating bacteria, after which they die through apoptosis. We now demonstrate that enhanced IgA-induced phagocytosis of bacteria or beads by neutrophils led to increased cell death. Nuclear changes and positivity for the general cell death marker 7-aminoactinomycin D were observed, but the absence of annexin V membrane staining supported that neutrophils did not die via apoptosis, in contrast to neutrophils that had not phagocytosed bacteria. Moreover, increased release of neutrophil extracellular traps (NETs) was observed, which was most likely due to augmented production of reactive oxygen species after uptake of IgA-opsonized particles. Blocking the IgA Fc receptor FcαRI abrogated phagocytosis and NET formation. Thus, FcαRI triggering on neutrophils resulted in a rapid form of cell death that is referred to as NETosis, as it is accompanied by the release of NETs. As such, IgA may play a prominent role in mucosal inflammatory responses, where it is the most prominent Ab, because it enhanced both phagocytosis of bacteria and formation of NETs, which are effective mechanisms that neutrophils employ to eliminate pathogens.

The IgG and IgM isotypes of anti-annexin A5 antibodies: relevance for primary antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is an autoimmune disease that is characterized by the presence of thromboses and/or recurrent pregnancy losses (RPL). The persistent presence of antiphospholipid antibodies (aPL Abs): IgG and/or IgM isotypes of the anticardiolipin and/or anti-ß2 glycoprotein I antibodies and lupus anticoagulant is mandatory for the laboratory diagnosis of APS. Due to the heating debate on the relevance of the IgM isotype of aPL Abs as a laboratory criterion defining APS, the focus of this article was to analyze whether both the IgG and IgM isotype of anti-annexin A5 Abs have equal relevance for clinical and serological features of patients with primary APS (PAPS). The IgG isotype of anti-annexin A5 Abs is associated with RPL in PAPS patients, although it is not elucidated whether these Abs are the cause or the consequence of RPL in PAPS. No data that could substantiate the association of the IgG and/or the IgM isotypes of anti-annexin A5 Abs with the presence of arterial and/or venous thromboses and/or their main complications in PAPS is available so far. However, the presence of clinical manifestations of the PAPS is increasing with the multiple positivity for aPL Abs and the IgM isotype of anti-annexin A5 Abs. The importance of the IgM isotype of anti-annexin A5 Abs in PAPS needs further elucidation due to the facts that majority of the available articles did not differentiate between both isotypes or only investigated the IgG isotype of anti-annexin A5 Abs.

Examining the prevalence of non-criteria anti-phospholipid antibodies in patients with anti-phospholipid syndrome: a systematic review.

OBJECTIVE: To systematically review and establish the prevalence of antibody positivity in assays not currently included in the APS classification criteria to detect antibodies directed against other phospholipids (PLs), PL binding proteins, coagulation factors and a mechanistic test for resistance of Annexin A5 (AnxA5) anticoagulant activity in APS and control populations. METHODS: We searched PubMed and EMBASE using the key words APS, antiphospholipid antibodies, non-criteria, new assays, IgA anticardiolipin antibodies, lupus anticoagulant, anti-Domain I, IgA anti-ß2-glycoprotein I antibodies, antiphosphatidylserine, anti-phosphatidylethanolamine, anti-phosphatidic acid, antiprothrombin, antiphosphatidylserine-prothtombin, anti-vimentin/cardiolipin complex and Annexin A5 resistance. Studies that met inclusion criteria to describe prevalence of non-criteria aPLs in APS patients (n > 10), disease and healthy control subjects were systematically examined. RESULTS: We selected 16 retrospective studies of 1404 APS patients, 1839 disease control and 797 healthy controls. The highest prevalence of non-criteria aPLs in the largest number of patients with APS was found in IgA anti-ß2GPI studies (129/229, 56.3%), AnxA5R (87/163, 53.4%) and IgG anti-Domain I (241/548, 44.0%). CONCLUSION: Our finding of a significantly high prevalence of all non-criteria aPLs studied in patients with APS compared with controls was tempered by wide variation in sample size, retrospective collection, assay methodology and different determination of positivity. Therefore, prospective studies of sufficient size and appropriate methodology are required to evaluate the significance of these assays and their utility in the management of patients with APS.

Pandemic influenza immunization in primary antiphospholipid syndrome (PAPS): a trigger to thrombosis and autoantibody production?

OBJECTIVE: The objective of this report is to conduct short- and long-term evaluation of a large panel of antiphospholipid (aPL) autoantibodies following pandemic influenza A/H1N1 non-adjuvant vaccine in primary antiphospholipid syndrome (PAPS) patients and healthy controls. METHODS: Forty-five PAPS and 33 healthy controls were immunized with H1N1 vaccine. They were prospectively assessed at pre-vaccination, and three weeks and six months after vaccination. aPL autoantibodies were determined by an enzyme-linked immunosorbent assay (ELISA) and included IgG/IgM: anticardiolipin (aCL), anti-beta2glycoprotein I (anti-ß2GPI); anti-annexin V, anti-phosphatidyl serine and anti-prothrombin antibodies. Anti-Sm was determined by ELISA and anti-double-stranded DNA (anti-dsDNA) by indirect immunofluorescence. Arterial and venous thrombosis were also clinically assessed. RESULTS: Pre-vaccination frequency of at least one aPL antibody was significantly higher in PAPS patients versus controls (58% vs. 24%, p = 0.0052). The overall frequencies of aPL antibody at pre-vaccination, and three weeks and six months after immunization remained unchanged in patients (p = 0.89) and controls (p = 0.83). The frequency of each antibody specificity for patients and controls remained stable in the three evaluated periods (p > 0.05). At three weeks, two PAPS patients developed a new but transient aPL antibody (aCL IgG and IgM), whereas at six months new aPL antibodies were observed in six PAPS patients and none had high titer. Anti-Sm and anti-dsDNA autoantibodies were uniformly negative and no new arterial or venous thrombosis were observed throughout the study. CONCLUSIONS: This is the first study to demonstrate that pandemic influenza vaccine in PAPS patients does not trigger short- and long-term thrombosis or a significant production of aPL-related antibodies (ClinicalTrials.gov, #NCT01151644).

Plasma annexin A5, anti-annexin A5 antibodies and annexin A5 polymorphism in Egyptian female patients with systemic lupus erythematosus and antiphospholipid syndrome.

BACKGROUND: Annexin A5 exhibits anticoagulant properties that appear to be defective in patients with antiphospholipid syndrome (APS) resulting in repeated thrombosis and recurrent pregnancy loss (RPL). APS occurs frequently in association with systemic lupus erythematosus (SLE). The present study aimed to find out a possible relationship between annexin A5 (gene polymorphism, antibodies or plasma level) and the pathophysiology of SLE, APS and RPL. METHODS: 47 female patients divided into 3 groups (SLE, APS and RPL) and 20 healthy controls are included in the study. Detection of annexin A5 (-1C/T) gene polymorphism was done by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) assay. Anti-annexin A5 antibodies (IgG and IgM) and annexin A5 plasma level were measured by Enzyme Linked Immunosorbent Assay (ELISA). RESULTS: The frequency of annexin A5 (-1C/T) polymorphism was significantly higher in SLE related groups (p = 0.02), but it did not correlate with RPL (p = 0.57) or annexin A5 level (p = 0.5). Anti-annexin A5 IgM level was significantly higher among APS patients and was associated with RPL (p = 0.005, odds ratio = 23.75, 95% confidence interval = 2.15 - 262.48). CONCLUSIONS: Annexin A5 (-1C/T) gene mutation may play a role in the pathophysiology of SLE. Anti-annexin A5 IgM was the antibody associated with RPL in this group of APS patients. Annexin A5 plasma levels are not affected by the presence of annexin A5 (-1C/T) polymorphism.

Association of Anti-Annexin A5 Antibody With Pregnancy Outcomes: A Cohort Study: Anti-annexin A5 antibody with pregnancy outcomes.

OBJECTIVE: This study aims to evaluate the correlation between anti-annexin A5 (aANXA5) antibody in the blood and pregnancy outcomes . METHODS: This study is a retrospective cohort study based on singleton pregnancies of the Third Affiliated Hospital of Wenzhou Medical University from May 2018 to December 2022. Baseline characteristics were collected from all participants. Logistic regression and interaction effect analyses were utilized to examine the risk impact of aANXA5 on pregnancy complications, adjusting for age, BMI, abortion, ANA, and aCL. Restricted cubic spline (RCS) and threshold effect analysis were applied to explore the relationship between aANXA5 levels and preterm birth (PTB), as well as pregnancy-induced hypertension (PIH). RESULTS: The study included 501 participants, with 51 (10.2%) testing positive for aANXA5 and 450 (89.8%) testing negative. The aANXA5 positive group exhibited higher rates of ANA and antibodies to thyroglobulin (TGAb), along with increased incidences of PTB and PIH. Positive aANXA5 status was independently linked to an elevated risk of PTB (OR: 2.53, 95% CI: 1.30-4.94) and PIH (OR: 4.23, 95% CI: 1.54-11.62). Subsequent subgroup analysis indicated no significant interaction between the groups (p > 0.05). Threshold analysis revealed that the OR for PTB was 1.20 (95% CI: 1.03-1.39) in participants with aANXA5 levels ≥ 32.77 ng/mL, and the OR for PIH was 1.62 (95% CI: 1.15-2.28) in those with aANXA5 levels ≥ 33.20 ng/mL. CONCLUSION: AANXA5 is independently associated with an increased risk of PTB and PIH. The identified optimal predictive cutoff values are 32.77 ng/mL for PTB and 33.20 ng/mL for PIH.

Seronegative antiphospholipid syndrome.

APS is an autoimmune disease that leads to arterial and/or venous thrombosis, recurrent pregnancy loss and persistently positive aPLs. Patients with clinical manifestations highly suggestive of APS but persistently negative conventional aPLs are classified as having seronegative APS. Ongoing research has revealed the existence of non-criteria antibodies proposed to be relevant to APS and that can be potentially included in the disease's classification criteria. We present a literature review on the most promising antibodies of this heterogeneous aPL family, which includes antibodies to a zwitterionic phospholipid, namely phosphatidylethanolamine, phospholipid-binding plasma proteins, phospholipid-protein complexes and anionic phospholipids other than cardiolipin. Although these molecules can increase the diagnostic yield of APS, their clinical relevance is still debatable and needs to be confirmed by interlaboratory efforts toward standardizing diagnostic tools, in addition to experimental data and larger longitudinal studies.

[Antibodies against phospholipids in patients with normal pregnancy].

We investigated the serum levels of IgG and IgM anticardiolipin (ACL), anti-beta-2-glycoprotein I (B2GPI), anti-phosphatidyl serine (PS), anti-prothrombin(PT), anti-annexin V (AnV) and anti-ethanolamine (Eth) antibodies using an ELISA method (Orgentec, Germany) in 16 females with normal pregnancy in the I, II and Ill trimester. We observed the following changes: 1. Elevation of the IgG u IgMACL, IgG PS, IgM Pr antibodies in the II and decreasing in the Ill trimester. 2. Decreasing of IgG u IgM B2GPI, IgG u IgM AnV, IgG Pr, IgG u IgM Eth antibodies in the II trimester, maintainante of the levels or more decreasing in the Ill trimester. 3. Increasing of lgM PS in the II and more increasing in the Ill trimester. All of these changes have no significant values (p > 0,05). In 10/16 we found extreme values of different antibodies, but all of them had normal delivery.

Annexin-V promotes anti-tumor immunity and inhibits neuroblastoma growth in vivo.

The goal of the current study is to determine the effects of blocking phosphatidylserine (PS) on the growth of neuroblastoma in mice. PS, an anionic phospholipid restricted to the cytoplasmic surface of plasma membranes in most cells, is externalized to the surface of apoptotic cells. PS has been shown to induce immune tolerance to self-antigens. PS can also be found on the surface of live cells and in particular tumor cells. Annexin-V (AnV) is a protein that specifically binds and blocks PS. To determine the effects of blocking PS with AnV on tumor growth and immunogenicity, mice were inoculated with AGN2a, a poorly immunogenic murine neuroblastoma that expresses high level of PS on the cell surface. Survival and anti-tumor T cell response were determined. AGN2a were engineered to secrete AnV. Secreted protein effectively blocked tumor PS. 40 % of mice inoculated with AnV-expressing AGN2a cells survived free of tumor, whereas none of the mice inoculated with control cells survived (p = 0.0062). The benefits of AnV were lost when mice were depleted of T cells. The findings suggest that AnV could protect mice from tumor challenge through an immune mediated mechanism. Mice were then immunized with irradiated AnV-secreting or control cells, and challenged with wild-type AGN2a cells. AnV-secreting cell vaccine protected 80 % of mice from AGN2a challenge, while control cell vaccine prevented tumor growth in only 30 % of animals (p = 0.012). ELISPOT analysis demonstrated that AnV-secreting cell vaccine induced a greater frequency of interferon-gamma producing splenic T cells. T cells isolated from mice immunized with AnV-secreting but not control vaccine lysed AGN2a. In summary, AnV blocked PS, enhanced T cell mediated tumor immunity, and inhibited tumor growth.

Acute resistance training affects cell surface markers for apoptosis and migration in CD4⁺ and CD8⁺ lymphocytes.

The purpose of the present study was to examine the acute effects of resistance training (RT) on CD4⁺ and CD8⁺ T lymphocytes apoptosis (annexin V⁺) and migration (CX3CR1). Twelve subjects performed two RT sessions (3 sets of 9 exercises) with 1 min (Hyper-1) and 3 min (Hyper-3) of rest-interval length between sets and exercises. CD4⁺ and CD8⁺ cells count displayed no change following Hyper-1 and Hyper-3. There was an increase in the percentage of CD4⁺ positive for annexin V⁺ and CX3CR1⁺ immediately after and 24 h post Hyper-1. Percentage of CD4⁺ positive for annexin V⁺ increased 2 and 24 h post Hyper-3, and decreased after CXCR1⁺ for the same time-points. There was an increase in CD8⁺ positive for annexin V⁺ and CX3CR1⁺ immediately after, 2 and 24 h post Hyper-1 and Hyper-3, while no differences were found between Hyper-1 and Hyper-3. Acute RT increase the apoptosis and migration of CD4⁺ and CD8⁺ lymphocytes even 24h after exercise, with minimal effects of rest-interval length.

Tolerogenic effects of interferon-gamma with induction of allergen-specific interleukin-10-producing regulatory B cell (Br1) changes in non-IgE-mediated food allergy.

In this study, specific oral tolerance induction using interferon-gamma (IFN-γ) could successfully treat food allergies. Allergen-specific IL-10-producing regulatory B cell (Br1) responses are characteristic in immune tolerance of food allergies. The in-vivo effects of IFN-γ on allergen-induced changes in Br1 proportion and numbers in food allergies were investigated. Oral food challenges were conducted and 20 allergic patients to cow's milk were selected. Of these 20 patients, five were treated with IFN-γ and milk (SOTI group), five were treated with only milk, five were treated with only IFN-γ, and five did not receive any treatment. In addition, 10 milk-tolerant subjects were involved in this study. Peripheral blood mononuclear cells (PBMCs) were stimulated using casein and stained for CD5, CD19, annexin V, and IL-10 before and after treatment. Allergy tolerance was induced only in the SOTI group along with induction of allergen-induced Br1 changes. Thus, IFN-γ can show tolerogenic effects in vivo when introduced with an allergen, which may be at least partly due to its effect on allergen-induced Br1 responses.

Deterioration of thromboses in primary antiphospholipid syndrome: TNF-alpha and anti-annexin A5 antibodies.

BACKGROUND: To investigate the association between clinical and serological features of patients with primary antiphospholipid syndrome (PAPS) and TNF-alpha, interleukin 6 (IL-6), and soluble IL-2 receptor (sIL-2R). METHODS: ELISA was used for measurement of antibodies (Abs) and TNF-alpha, while IL-6 and sIL-2R were measured by chemiluminescence. RESULTS: PAPS patients with pulmonary emboli showed positive correlation between IgM isotype of anti-annexin A5 antibodies and TNF-alpha (r = 0.894, p = 0.041) and IgM class of anticardiolipin antibodies and sIL-2R (r = 0.900, p = 0.037). In PAPS with cerebrovascular insults, positive correlation was noticed between TNF-alpha and IgG isotype of anticardiolipin (r = 0.624, p = 0.040) and anti-annexinA5 Abs (r = 0.768, p = 0.006). CONCLUSIONS: Isotype analysis of antiphospholipid and anti-annexin A5 Abs and investigation of their association with TNF-alpha is important for differentiation of PAPS patients that are prone to further deterioration of arterial and venous thromboses.