CD200R activation on naïve T cells by B cells induces suppressive activity of T cells via IL-24.

CD200 is an anti-inflammatory protein that facilitates signal transduction through its receptor, CD200R, in cells, resulting in immune response suppression. This includes reducing M1-like macrophages, enhancing M2-like macrophages, inhibiting NK cell cytotoxicity, and downregulating CTL responses. Activation of CD200R has been found to modulate dendritic cells, leading to the induction or enhancement of Treg cells expressing Foxp3. However, the precise mechanisms behind this process are still unclear. Our previous study demonstrated that B cells in Peyer's patches can induce Treg cells, so-called Treg-of-B (P) cells, through STAT6 phosphorylation. This study aimed to investigate the role of CD200 in Treg-of-B (P) cell generation. To clarify the mechanisms, we used wild-type, STAT6 deficient, and IL-24 deficient T cells to generate Treg-of-B (P) cells, and antagonist antibodies (anti-CD200 and anti-IL-20RB), an agonist anti-CD200R antibody, CD39 inhibitors (ARL67156 and POM-1), a STAT6 inhibitor (AS1517499), and soluble IL-20RB were also applied. Our findings revealed that Peyer's patch B cells expressed CD200 to activate the CD200R on T cells and initiate the process of Treg-of-B (P) cells generation. CD200 and CD200R interaction triggers the phosphorylation of STAT6, which regulated the expression of CD200R, CD39, and IL-24 in T cells. CD39 regulated the expression of IL-24, which sustained the expression of CD223 and IL-10 and maintained the cell viability. In summary, the generation of Treg-of-B (P) cells by Peyer's patch B cells was through the CD200R-STAT6-CD39-IL-24 axis pathway.

Identifying factors associated with substantially reduced adult height in patients with juvenile idiopathic arthritis: a retrospective cohort study.

BACKGROUND: Juvenile idiopathic arthritis (JIA), an autoimmune disease affecting children or adolescents and causing joint or systemic symptoms, reportedly has a negative effect on the patients' body height. This study aimed to identify factors attributable to substantially reduced adult height (SRAH) in JIA patients. METHODS: This single-center retrospective cohort study included patients from 2009 to 2019 in Taiwan. We collected JIA patients aged > 18 years at enrollment with a definite diagnosis and undergoing regular outpatient clinic follow-up or disease remission. Target height difference (THD), defined by adult height minus mid-parental height, was calculated for each patient. The calculation results yielded two groups, of which positive THD was defined as the optimal height (OH group) and those with THD below two standardized deviations as the SRAH group. Descriptive statistics and logistic regression analysis were used to analyze the data. RESULTS: Of 92 JIA patients, 57 and 12 were in the OH and the SRAH groups. Earlier disease onset, especially before the six-year-old, was noted in the SRAH group (p = 0.026). The distribution of JIA subtypes differed significantly between the two groups (p < 0.001); enthesis-related arthritis was the commonest subtype in the OH group, and systemic JIA was the commonest in the SRAH group. Half of the patients in the SRAH group had an active disease status at enrollment, which was higher than the OH group (50.0% vs. 21.1%, p = 0.066). More patients in the SRAH group had received orthopedic surgery due to JIA (25% vs. 3.5%, p = 0.034). Multiple logistic regression analysis showed that SRAH was independently related to systemic JIA (OR = 37.6, 95%CI 1.2-1210.5; p = 0.041). CONCLUSION: The subtype of systemic JIA, with its characteristics of early disease onset and active disease status, was the essential factor that significantly impacted adult height.

The characteristics and risk factors of cerebrovascular events in young systemic lupus erythematosus patients: A case-control study.

OBJECTIVES: We clarified the characteristics and risk factors of CVEs in young SLE patients. METHOD: We retrospectively reviewed the medical records of patients younger than 50 years of age diagnosed with SLE and first CVEs from 1995 to 2020 in a tertiary medical center in Taiwan. We collected data on the patient characteristics before the CVE and reviewed the laboratory data obtained during the period. At a ratio of 1:3, cases and controls were matched with sex, SLE diagnosis age, diagnosis year, and SLE duration. RESULTS: We enrolled 43 CVE SLE patients and matched 129 non-CVE SLE controls. The median age at the time of the CVE was 39 years. Around 70% of young-aged CVE involved the cerebral lobes of frontal (∼30%), parietal (∼20%), occipital (∼10%), and temporal (∼10%). The peak incidence period for hemorrhagic CVE was within 1st year of SLE diagnosis (37%); in contrast, during the 2nd to 5th year of SLE diagnosis (25%) for ischemia CVEs. Hyperlipidemia (odds ratio [OR] = 19.36, p = 0.002), anti-phospholipid syndrome (APS) (OR = 41.9, p = 0.0068), a lower hemoglobin level (OR = 0.66, p = 0.0192), and a higher SLE Disease Activity Index (SLEDAI-2k) score (OR = 1.22, p = 0.0019) were independent risk factors for CVEs in young SLE patients. CONCLUSION: Hyperlipidemia, APS, low Hb level, and high SLEDAI-2k significantly increase the risk of young-aged SLE patients developing CVE.

M2-like macrophages polarized by Foxp3- Treg-of-B cells ameliorate imiquimod-induced psoriasis.

Our group have demonstrated that splenic B cells contributed to the CD4+ CD25- naive T cells conversion into CD4+ CD25+ Foxp3- regulatory T cells without adding appended cytokines, named Treg-of-B cells which were potent suppressors of adaptive immunity. We like to investigate whether Treg-of-B cells could promote alternatively activated macrophage (M2 macrophages) polarization and alleviate inflammatory disease, psoriasis. In this study, we co-cultured the bone marrow-derived macrophages (BMDMs) with Treg-of-B cells under LPS/IFN-γ stimulation and analyzed the M2-associated gene and protein using qPCR, western blotting, and immunofluorescence staining. We also examined the therapeutic effect of Treg-of-B cell-induced M2 macrophage for skin inflammation using imiquimod (IMQ)-induced psoriatic mouse model. Our results showed that BMDMs co-cultured with Treg-of-B cells upregulated typical M2-associated molecules, including Arg-1, IL-10, Pdcd1lg2, MGL-1, IL-4, YM1/2 and CD206. In an inflammatory environment, TNF-α and IL-6 production by macrophages co-cultured with Treg-of-B cells was decreased significantly. The molecular mechanism revealed that Treg-of-B cells promoted M2 macrophage polarization via STAT6 activation in a cell contact-dependent manner. Moreover, the treatment with Treg-of-B cell-induced M2 macrophages attenuated the clinical manifestations of psoriasis, such as scaling, erythema and thickening in the IMQ-induced psoriatic mouse model. T cell activation in draining lymph nodes was decreased in the Treg-of-B cell-induced M2 macrophage group after IMQ application. In conclusion, our findings suggested that Foxp3- Treg-of-B cells could induce alternatively activated M2 macrophages through STAT6 activation, providing a cell-based therapeutic strategy for psoriasis.

A novel mucosal bivalent vaccine of EV-A71/EV-D68 adjuvanted with polysaccharides from Ganoderma lucidum protects mice against EV-A71 and EV-D68 lethal challenge.

BACKGROUND: Human enteroviruses A71 (EV-A71) and D68 (EV-D68) are the suspected causative agents of hand-foot-and-mouth disease, aseptic meningitis, encephalitis, acute flaccid myelitis, and acute flaccid paralysis in children. Until now, no cure nor mucosal vaccine existed for EV-A71 and EV-D68. Novel mucosal bivalent vaccines are highly important for preventing EV-A71 and EV-D68 infections. METHODS: In this study, formalin-inactivated EV-A71 and EV-D68 were used as antigens, while PS-G, a polysaccharide from Ganoderma lucidum, was used as an adjuvant. Natural polysaccharides have the characteristics of intrinsic immunomodulation, biocompatibility, low toxicity, and safety. Mice were immunized intranasally with PBS, EV-A71, EV-D68, or EV-A71 + EV-D68, with or without PS-G as an adjuvant. RESULTS: The EV-A71 + EV-D68 bivalent vaccine generated considerable EV-A71- and EV-D68-specific IgG and IgA titres in the sera, nasal washes, saliva, bronchoalveolar lavage fluid, and feces. These antibodies neutralized EV-D68 and EV-A71 infectivity. They also cross-neutralized infections by different EV-D68 and EV-A71 sub-genotypes. Furthermore, compared with the PBS group, EV-A71 + EV-D68 + PS-G-vaccinated mice exhibited an increased number of EV-D68- and EV-A71-specific IgA- and IgG-producing cells. In addition, T-cell proliferative responses, and IFN-γ and IL-17 secretion in the spleen were substantially induced when PS-G was used as an adjuvant with EV-A71 + EV-D68. Finally, in vivo challenge experiments demonstrated that the immune sera induced by EV-A71 + EV-D68 + PS-G conferred protection in neonate mice against lethal EV-A71 and EV-D68 challenges as indicated by the increased survival rate and decreased clinical score and viral RNA tissue expression. Taken together, all EV-A71/EV-D68 + PS-G-immunized mice developed potent specific humoral, mucosal, and cellular immune responses to EV-D68 and EV-A71 and were protected against them. CONCLUSIONS: These findings demonstrated that PS-G can be used as a potential adjuvant for EV-A71 and EV-D68 bivalent mucosal vaccines. Our results provide useful information for the further preclinical and clinical development of a mucosal bivalent enterovirus vaccine against both EV-A71 and EV-D68 infections.

Circulating SSEA-1+ stem cell-mediated tissue repair in allergic airway inflammation.

Structural changes known as airway remodeling characterize chronic/severe asthma and contribute to lung dysfunction. We previously reported that neonatal SSEA-1+ pulmonary stem/progenitor cells (PSCs) ameliorated airway inflammation in asthmatic mice. However, the molecular mechanisms by which endogenous SSEA-1+ PSC of adult mice afford beneficial effects in alveolar homeostasis and lung repair after allergen challenge remain incompletely understood. To analyze the expression profile and clarify the biological significance of endogenous adult lung SSEA-1+ cells in asthmatic mice. Lung SSEA-1+ cells and circulating SSEA-1+ cells in peripheral blood were determined by confocal microscopy and cytometric analysis. GFP chimeric mice were used to trace cell lineage in vivo. The roles of circulating SSEA-1+ cells were verified in ovalbumin-induced and house dust mite-induced allergic asthmatic models. In asthmatic mice, endogenous lung SSEA-1+ cells almost disappeared; however, a unique population of circulating SSEA-1+ cells was enriched after the challenge phase. In asthmatic mice, adoptive transfer of circulating SSEA-1+ cells had a specific homing preference for the lung in response to inhaled antigen through upregulating CXCR7-CXCL11 chemokine axis. Circulating SSEA-1+ cells can transdifferentiate in the alveolar space and ameliorate lung inflammation and structural damage through inhibiting the infiltration of inflammatory cells into peribronchovascular and goblet cell hyperplasia areas, reducing the thickened smooth muscle layers and PAS-positive mucus-containing goblet cells. Reinforcing bone marrow-derived circulating SSEA-1+ cells from peripheral blood into lung tissue which create a rescue mechanism in maintaining alveolar homeostasis and tissue repair to mediate lung protection for emergency responses after allergen challenge in asthmatic conditions.

Clinical and Immunological Defects and Outcomes in Patients with Chromosome 22q11.2 Deletion Syndrome.

BACKGROUND: Chromosome 22q11.2 deletion syndrome (22q11.2DS) is the most common microdeletion syndrome in humans and can present with highly variable clinical manifestations. Immune deficiencies occur because of thymic hypoplasia or aplasia. METHODS: This retrospective study included patients diagnosed with 22q11.2DS at a medical center between 2000 and 2021. We analyzed the association between clinical phenotypes, immunological abnormalities, age, and outcomes. RESULTS: Eighty-seven patients with 22q11.2DS had a median diagnostic age of 1.78 months. Patients presented with congenital heart disease (CHD; 86.2%), major infections (75.9%), and failure to thrive (FTT; 58.6%). Autoimmunity, neuropsychiatric disorders, and hypoparathyroidism were significantly associated. Neonatal seizures were associated with early diagnosis before 2 months (OR 8.56, 95% CI 1.21-60.58, P = 0.032). Immunological abnormalities included lymphopenia (93.1%), T lymphopenia (71.9%), CD4+ T lymphopenia (64.1%), a lack of hepatitis B vaccine antibodies (46.2%), and complete DiGeorge syndrome (cDGS) (2.3%). Severe lymphopenia and T lymphopenia improved at 3 years of age. Two patients with cDGS were treated with hematopoietic stem cell transplantation, and one survived. The mortality rate was 12.8% and the estimated 35-year survival probability was 77.5%. Major infections experienced > four times were significantly associated with a decreased survival rate of 60%. Patients with CHD without FTT or recurrent infections had a better 20-year survival rate (96.2%). CONCLUSIONS: CHD, major infection, and FTT were common manifestations and poor prognostic factors. Autoimmunity, neuropsychiatric disorders, and hypoparathyroidism were significantly associated. Although T lymphopenia may improve with age, patients with 22q11.2DS require lifelong monitoring for immune dysregulation.

Predictive characteristics to discriminate the longitudinal outcomes of childhood asthma: a retrospective program-based study.

BACKGROUND: Childhood asthma is an inflammatory disease with heterogeneous outcomes. We sought to determine the impact of total IgE, blood eosinophil, allergen sensitization, and inhaled corticosteroid (ICS) on longitudinal outcomes and to identify characteristics for discriminating different outcomes. METHODS: We conducted a retrospective study in 383 childhood asthma patients and another 313 patients with blood eosinophil data only receiving regular program-based visits from September 1, 2004, to December 31, 2018. Peak expiratory flow (PEF) variability, PEF predicted %, asthma severity, and asthma control at each visit were assessed as clinical outcomes. RESULTS: Our data show that the percentage of blood eosinophils was significantly associated with increased asthma severity (OR: 1.043, 95% CI: 1.002-1.086, P = 0.0392). Mold sensitization was significantly associated with asthma severity (OR: 2.2485, 95% CI: 1.3253-3.8150, P = 0.0027). Characteristics including sensitization status plus ICS dosage had the best area under the receiver operating characteristic curve (AUC) value for predicting longitudinal PEF predicted % (0.6609), PEF variability (0.6885), asthma severity (0.5918), and asthma control (0.6441), respectively. CONCLUSIONS: We showed that the risk for adverse clinical outcomes at follow-up differed between serum IgE, blood eosinophil, and allergen sensitization identified at baseline. Sensitization and ICS dosage were predictive characteristics of long-term clinical outcomes. IMPACT: The unique aspects of the study are its longitudinal assessment of patients receiving guideline-based asthma management program to help characterize the stability of the clinical outcomes over time. Characteristics including allergen sensitization and ICS dosage demonstrated an improved capability for distinguishing between better and worse clinical outcomes. Through longitudinal serial assessment, this study indicates the risk for adverse clinical outcomes differed between children with serum IgE/blood eosinophil/allergen sensitization characterized at baseline.

Lower caprylate and acetate levels in the breast milk is associated with atopic dermatitis in infancy.

BACKGROUND: Atopic dermatitis (AD) occurs in exclusively breastfed infants. As fatty acids have some immunomodulatory effect, we aimed to investigate the influence of fatty acid compositions in breast milk (BM) on the development of AD in exclusively breastfed infants. METHODS: We enrolled two- to four-month-old exclusively breastfed infants. The objective SCORing Atopic Dermatitis (objSCORAD) was evaluated. The lipid layer of BM was analyzed by gas chromatography for fatty acid levels. Medical charts were reviewed. RESULTS: Forty-seven AD infants and 47 healthy controls were enrolled. The objSCORAD was 20.5 ± 1.7 (shown as mean ± SEM) in the AD group. The age, sex, parental atopy history, and nutrient intake of mothers were not significantly different between two groups. The palmitate and monounsaturated fatty acid (MUFA) levels in BM positively correlated with objSCORAD, while caprylate, acetate, and short-chain fatty acid (SCFA) levels negatively correlated with objSCORAD (p = .031, .019, .039, .013, .022, respectively). However, the butyrate levels in BM were not significantly different. The caprylate and acetate levels in BM were significantly associated with the presence of infantile AD (p = .021 and .015, respectively) after adjusting for age, sex, parental allergy history, MUFA, palmitate, and SCFA levels in BM. ObjSCORAD in infancy was significantly associated with persistent AD (p = .026) after adjusting for age, sex, parental atopy history, caprylate, palmitate, MUFA, acetate, and SCFA levels in BM. CONCLUSION: Caprylate and acetate levels in BM for exclusively breastfed infants were negatively associated with objSCORAD. Lower caprylate and acetate in BM might be the risk factors for infantile AD, while butyrate in BM was not associated with infantile AD.

Innate immune response analysis in COVID-19 and kawasaki disease reveals MIS-C predictors.

BACKGROUND/PURPOSE: The association between dysregulated innate immune responses seen in Kawasaki disease (KD) with predisposition to Kawasaki-like multisystem inflammatory syndrome in children (MIS-C) remains unclear. We aimed to compare the innate immunity transcriptome signature between COVID-19 and KD, and to analyze the interactions of these molecules with genes known to predispose to KD. METHODS: Transcriptome datasets of COVID-19 and KD cohorts (E-MTAB-9357, GSE-63881, GSE-68004) were downloaded from ArrayExpress for innate immune response analyses. Network analysis was used to determine enriched pathways of interactions. RESULTS: Upregulations of IRAK4, IFI16, STING, STAT3, PYCARD, CASP1, IFNAR1 and CD14 genes were observed in blood cells of acute SARS-CoV-2 infections with moderate severity. In the same patient group, increased expressions of TLR2, TLR7, IRF3, and CD36 were also noted in blood drawn a few days after COVID-19 diagnosis. Elevated blood PYCARD level was associated with severe COVID-19 in adults. Similar gene expression signature except differences in TLR8, NLRP3, STING and IRF3 levels was detected in KD samples. Network analysis on innate immune genes and genes associated with KD susceptibility identified enriched pathways of interactions. Furthermore, higher expression levels of KD susceptibility genes HLA-DOB, PELI1 and FCGR2A correlated with COVID-19 of different severities. CONCLUSION: Our findings suggest that most enriched innate immune response pathways were shared between transcriptomes of KD and COVID-19 with moderate severity. Genetic polymorphisms associated with innate immune dysregulation and KD susceptibility, together with variants in STING and STAT3, might predict COVID-19 severity and potentially susceptibility to COVID-19 related MIS-C.

Dynamics of cellular immune responses in recipients of renal allografts positive for hepatitis B surface antigen.

BACKGROUND/PURPOSE: Hepatitis B surface antigen (HBsAg)-positive renal transplantation recipients must take lifelong immunosuppressants and nucleotide analogues (NAs). We investigated the cellular immune responses of HBsAg-positive renal transplantation recipients taking immunosuppressants and NAs. METHODS: Blood samples were collected from HBsAg-positive individuals with end-stage renal disease on the transplant waiting list (Group 1) and renal transplantation recipients taking immunosuppressants and NAs (Group 2) or immunosuppressants without NAs (Group 3). Hepatitis B virus (HBV)-specific pentamers were used to quantify circulating HBV-specific CD8+ T cells. RESULTS: Groups 2 and 3 had higher cellular immune responses, as indicated by significantly lower regulatory T (Treg)/CD8+ T cell ratios than Group 1. With undetectable viral loads under both immunosuppressant and NAs, the CD8+ T cell and HBV-specific CD8+ T cell frequencies were similar in Group 2 and Group 1. Patients in Group 3 did not use NAs and had an elevated viral load and higher HBV-specific CD8+ T cell and IFN-γ-producing HBV-specific CD8+ T cell frequencies, but lower a frequency of programmed death-1 (PD-1)+ HBV-specific CD8+ T cells than the other groups. Increased viral replication in Group 3 resulted in significantly higher CD8+ T cell and IFN-γ-producing CD8+ T cell frequencies than Group 1. CONCLUSION: Immunosuppressant therapy increases viral replication in HBsAg-positive renal transplant recipients due to disabling or dysregulation of virus-specific CD8+ T cells. The higher cellular immune responses due to lower Treg/CD8+ T cell ratios in HBsAg-positive renal transplant recipients may be one of the reasons to induce liver pathology because of uncontrolled viral replication.

Topical Melatonin Exerts Immunomodulatory Effect and Improves Dermatitis Severity in a Mouse Model of Atopic Dermatitis.

Oral melatonin supplement has been shown to improve dermatitis severity in children with AD, but the mechanism of the effect is unclear, and it is uncertain whether melatonin has a direct immunomodulatory effect on the dermatitis. Topical melatonin treatment was applied to DNCB-stimulated Balb/c mice, and gross and pathological skin findings, serum IgE, and cytokine levels in superficial lymph nodes were analyzed. Secretion of chemokines and cell proliferative response after melatonin treatment in human keratinocyte HaCaT cells were also studied. We found that in DNCB-stimulated Balb/c mice, topical melatonin treatment improved gross dermatitis severity, reduced epidermal hyperplasia and lymphocyte infiltration in the skin, and decreased IP-10, CCL27, IL-4, and IL-17 levels in superficial skin-draining lymph nodes. Melatonin also reduced cytokine-induced secretion of AD-related chemokines IP-10 and MCP-1 and decreased IL-4-induced cell proliferation in HaCaT cells. Melatonin seems to have an immunomodulatory effect on AD, with IP-10 as a possible target, and topical melatonin treatment is a potentially useful treatment for patients with AD.

Butyrate modulates adipose-derived stem cells isolated from polygenic obese and diabetic mice to drive enhanced immunosuppression.

BACKGROUND AIMS: Adipose-derived stem cells (ASCs) offer promising therapeutic possibilities for immunomodulation. Butyrate (BA) exerts potent anti-inflammatory effects and exhibits multiple regulatory functionalities in adipose tissue (AT). The authors aimed to explore whether BA modulates ASCs to augment their immunosuppressive capabilities. METHODS: The authors examined the potency of BA and ASCs for controlling anti-CD3 plus CD28-stimulated splenocyte proliferation in vitro, both in combination and with pre-treatment. Further, the authors investigated genes specifically upregulated by BA-treated ASCs, which were harvested from ASC-splenocyte co-culture after the removal of floating splenocytes. In addition, the authors investigated the influence of oral BA supplementation on the ex vivo immunosuppressive potency of ASCs from BALB/c and Tsumura, Suzuki, obese, diabetes (TSOD) mice. RESULTS: BA enhanced the immunosuppressive potency of ASCs when directly added to ASC-splenocyte co-cultures or via pre-conditioning treatment. The percentages of ASC-induced Foxp3+ regulatory T cells increased, whereas the numbers of ASC-suppressed T helper 17 cells further decreased after BA exposure. The messenger RNA expression levels of inducible nitric oxide (NO) synthase (iNOS), chemokines, IL-10 and amphiregulin in ASCs co-cultured with activated splenocytes were upregulated after incubation with BA. This was accompanied by an amplification of iNOS-inducing cytokines, interferon gamma and tumor necrosis factor alpha in the ASC-splenocyte co-culture, triggering ASCs to produce high NO levels under the influence of BA. Mechanistically, the authors detected BA-mediated acetylated histone H3 in ASCs. BA treatment consistently improved the immunosuppressive potency of ASCs derived from both BALB/c and TSOD mice. CONCLUSIONS: The use of BA to counteract metaflammation by restoring the defective immunomodulation of ASCs from dysregulated AT in obese donors is recommended.

A significant improvement of thromboses treated by a new oral anticoagulant in an 11-year-old girl with systemic lupus erythematosus associated antiphospholipid syndrome: A case report.

Pediatric venous thrombosis is associated with a variety of chronic diseases. Antiphospholipid syndrome (APS) is one of them and is commonly related to systemic lupus erythematosus (SLE). Warfarin is the mainstream of anticoagulation treatment in pediatric APS currently but it needs close monitoring and frequent dose adjustment. New oral anticoagulants (NOAC) is one of the innovative options in recent years but there is a lack of report in secondary prevention of deep vein thrombosis (DVT), especially pediatric APS. Herein we reported the significant therapeutic effect of edoxaban in a 11-year-old girl of newly diagnosed SLE and APS, who had deep vein thrombosis as the initial presentation.

Aggressive corticosteroid treatment in childhood idiopathic pulmonary hemosiderosis with better outcome.

BACKGROUND/PURPOSE: Idiopathic pulmonary hemosiderosis (IPH) is a rare but fatal disease characterized by a triad of anemia, hemoptysis, and increased pulmonary infiltration. This study is aimed to review the clinical manifestations, diagnostic tools, medication and outcome of childhood IPH in Taiwan. METHODS: We retrospectively enrolled the patients less than 18 years old in National Taiwan University Hospital in the past 30 years. The clinical data were collected and analyzed. RESULTS: All of the twelve children diagnosed with IPH had anemia and increased pulmonary infiltration, eight had hemoptysis, and ten were confirmed with detection of hemosiderin-laden macrophages. The mean age at diagnosis were 4.9 (interquartile range 2.5-6.3) years old. Patients with high dose corticosteroid (CS, ≥ 1 mg/kg/day prednisolone equivalent) treatment had lower odds ratio for ICU admission and significant higher Hb recovery rate than those with mild disease activity not receiving high dose CS treatment (p = 0.011). The only factor that is significantly associated with persistent anemia is the usage of high dose CS (p < 0.001) after adjusting for hemoptysis, fulfilling triad, serum ferritin level, and ICU admission by multiple regression. The only factor that is significantly associated with ICU admission is the presence of microorganism yielded in sputum (p < 0.001) after adjusting for fever, serum ferritin level, usage of invasive MV, and high dose CS treatment days. CONCLUSION: The aggressive high dose CS therapy might prevent ICU admission and improve anemia. Aggressive high dose CS treatment is suggested in IPH patients regardless of the disease activity.

Experience of the use of hydroxychloroquine on patients with COVID-19: A perspective on viral load and cytokine kinetics.

Until now, there are no approved treatment against COVID-19. Hydroxychloroquine (HCQ) was hypothesized to be active against SARS-CoV2 via antiviral and anti-inflammatory effect; however, HCQ for COVID-19 in clinical use remained debating. In this preliminary report, we presented six patients with mild to moderate COVID-19. They were treated with HCQ for 14 days from the day of COVID-19 diagnosis. Serial viral load from respiratory specimens were performed every other day. Cytokine profile was checked before HCQ initiation and on the 14th day of HCQ treatment. All patients receiving HCQ completed 14-day course without complication. Among the six patients, the mean duration from symptom onset to last detectable viral load was 34 ± 12 days, which was similar to those without specific treatment in previous reports. Low level of interferon-gamma was noted in all patients of different stage of infection and three patients had elevation of IL-17 level. Prolonged virus shedding is still observed regardless HCQ. The impact of HCQ on cytokine kinetics remained unclear; however, IL-17 could be an inflammatory marker for disease status monitor and a potential therapeutic target.

Lymphopenia, Lymphopenia-Induced Proliferation, and Autoimmunity.

Immune homeostasis is a tightly regulated system that is critical for defense against invasion by foreign pathogens and protection from self-reactivity for the survival of an individual. How the defects in this system might result in autoimmunity is discussed in this review. Reduced lymphocyte number, termed lymphopenia, can mediate lymphopenia-induced proliferation (LIP) to maintain peripheral lymphocyte numbers. LIP not only occurs in normal physiological conditions but also correlates with autoimmunity. Of note, lymphopenia is also a typical marker of immune aging, consistent with the fact that not only the autoimmunity increases in the elderly, but also autoimmune diseases (ADs) show characteristics of immune aging. Here, we discuss the types and rates of LIP in normal and autoimmune conditions, as well as the coronavirus disease 2019 in the context of LIP. Importantly, although the causative role of LIP has been demonstrated in the development of type 1 diabetes and rheumatoid arthritis, a two-hit model has suggested that the factors other than lymphopenia are required to mediate the loss of control over homeostasis to result in ADs. Interestingly, these factors may be, if not totally, related to the function/number of regulatory T cells which are key modulators to protect from self-reactivity. In this review, we summarize the important roles of lymphopenia/LIP and the Treg cells in various autoimmune conditions, thereby highlighting them as key therapeutic targets for autoimmunity treatments.

CEACAM3 decreases asthma exacerbations and modulates respiratory syncytial virus latent infection in children.

BACKGROUND: Respiratory syncytial virus (RSV) is associated with childhood asthma. Nevertheless, not all children exposed to RSV develop asthma symptoms, possibly because genes modulate the effects of RSV on asthma exacerbations. OBJECTIVE: The purpose of this study was to identify genes that modulate the effect of RSV latent infection on asthma exacerbations. METHODS: We performed a meta-analysis to investigate differentially expressed genes (DEGs) of RSV infection from Gene Expression Omnibus datasets. Expression quantitative trait loci (eQTL) methods were applied to select single nucleotide polymorphisms (SNPs) that were associated with DEGs. Gene-based analysis was used to identify SNPs that were significantly associated with asthma exacerbations in the Taiwanese Consortium of Childhood Asthma Study (TCCAS), and validation was attempted in an independent cohort, the Childhood Asthma Management Program (CAMP). Gene-RSV interaction analyses were performed to investigate the association between the interaction of SNPs and RSV latent infection on asthma exacerbations. RESULTS: A total of 352 significant DEGs were found by meta-analysis of RSV-related genes. We used 38 123 SNPs related to DEGs to investigate the genetic main effects on asthma exacerbations. We found that eight RSV-related genes (GADD45A, GYPB, MS4A3, NFE2, RNASE3, EPB41L3, CEACAM6 and CEACAM3) were significantly associated with asthma exacerbations in TCCAS and also validated in CAMP. In TCCAS, rs7251960 (CEACAM3) significantly modulated the effect of RSV latent infection on asthma exacerbations (false-discovery rate <0.05). The rs7251960 variant was associated with CEACAM3 mRNA expression in lung tissue (p for trend=1.2×10-7). CEACAM3 mRNA was reduced in nasal mucosa from subjects with asthma exacerbations in two independent datasets. CONCLUSIONS: rs7251960 is an eQTL for CEACAM3, and CEACAM3 mRNA expression is reduced in subjects experiencing asthma exacerbations. CEACAM3 may be a modulator of RSV latent infection on asthma exacerbations.

Lower vitamin D levels in the breast milk is associated with atopic dermatitis in early infancy.

BACKGROUND: Our previous study showed that the discontinuation of breastfeeding could improve atopic dermatitis (AD) symptoms in exclusively breastfed infants. As vitamins A and D are influential on the immune system, we aimed to analyze the association of vitamin A and D levels in breast milk (BM) with AD. METHODS: We enrolled two- to four-month-old exclusively breastfed infants. The objective SCORing Atopic Dermatitis (objSCORAD) was evaluated. The lipid layer of BM was extracted and analyzed by liquid chromatography for vitamin A and D levels. Medical charts were reviewed for the clinical course of AD. RESULTS: Forty-five AD patients and 45 healthy controls were enrolled. The objSCORAD was 20.54 ± 1.73 (shown as mean ± SEM) in the AD group. The sex, parental atopy history, nutrient intake of mothers, and vitamin A levels in BM were not significantly different between the two groups. The 25-(OH) D3 level in BM was significantly lower in the AD group than in the control group (1.72 ± 0.30 and 3.95 ± 0.64 ng/mL, respectively; P = .001). The 25-(OH) D3 level negatively correlated with objSCORAD (P = .003). The only factor that is significantly associated with persistent AD is the objSCORAD in infancy (P = .003) after adjusting for age, sex, parental atopy history, and 25-(OH) D3 level by multiple regression. CONCLUSION: Vitamin D levels in BM for exclusively breastfed infants were negatively associated with objSCORAD. Lower vitamin D levels in BM might be a risk factor for infantile AD.

Telbivudine for renal transplant recipients with chronic hepatitis B infection: a randomized controlled trial with early termination.

BACKGROUND: The aim of this study was to analyze changes in renal function in HBsAg-positive renal transplant recipients receiving lamivudine who did or did not switch to telbivudine. METHODS: In this prospective randomized clinical trial (RCT), HBsAg-positive renal transplant recipients who had received lamivudine prophylaxis for at least 6 months were 1:2 randomized to receive either lamivudine or telbivudine for another 24 months. Renal function was evaluated by creatinine level and estimated glomerular filtration rate (eGFR) at the time of randomization (baseline), 6, 12, 18, and 24 months respectively. RESULTS: This RCT was prematurely terminated after recruiting only 17 patients due to a high incidence (61.5%; 8/13) of clinical myalgia in the telbivudine group. Cox's proportional hazards model revealed that there was no independent predictor of myalgia. Based on intention-to-treat and per protocol analyses using generalized estimating equations, the patients in the randomized telbivudine group had a significantly increased eGFR and the patients in the lamivudine group had a significantly decreased eGFR at the end of follow-up compared to the values at study enrollment. However, there was no significant difference between the lamivudine and telbivudine groups. CONCLUSIONS: The renal protective effect of telbivudine for HBsAg positive renal transplant recipients was uncertain for high incidence of myalgia and only patients who were on telbivudine for 24 months had renal function maintenance.