bluuebunny/crossref_metadata_2025 huggingface dataset:
Increase in T cell surface thiol levels are linked with activation and diabetogenicity
Authors: Tse Hubert Ming , Padgett Lindsey E. , Heath Katie E.
Published: January 2023

Free radicals contribute to Type 1 diabetes (T1D) autoimmune responses. We recently demonstrated that superoxide-deficient CD4 T cells exhibited increased effector responses and diabetogenicity, but the redox-dependent mechanism(s) mediating T cell activation were unclear. We hypothesized that during T1D progression, CD4 T cells with a reduced cell surface state would exhibit a concomitant increase in pro-inflammatory cytokine and chemokine responses. To test this, alexa fluor 647-conjugated maleimide (ALM)-labeling of cell surface reduced thiols on diabetogenic mouse and human CD4 T cells was performed. We observed an increase in ALM percentage and gMFI from peripheral Non-obese diabetic (NOD) mouse CD4 T cells during progression to overt diabetes. Cognate autoantigen stimulation elicited a 2- and 20-fold increase in CD4 ALM T cell percentage and gMFI, respectively. In addition to serving as a T cell activation marker, ALM gMFI of reduced CD4 T cell surface thiols was enhanced (1.2-fold) with Th1 polarization and blunted (12.2-fold) following Treg polarization in contrast to Th0 conditions. Cell surface reduced thiols from human CD4 T cells with recent-onset T1D exhibited elevated ALM percentage (1.6-fold, p < 0.05) and gMFI (1.7-fold, p = 0.1503) in comparison to age-matched healthy controls following polyclonal stimulation. Mirroring the increase in ALM with T1D individuals, PBMCs (n=12) also synthesized increased IFNγ (1.2-fold, p=0.0031), TNFα (1.3-fold, p=0.0022), and CXCL10 (1.2-fold, p=0.0145) in contrast to healthy controls (n=7). Our studies point to the exciting potential that oxidation of cell surface thiols on diabetogenic CD4 T cells could abrogate effector responses and correlate with CD4 T cell activation.
Antibiotics ameliorate lupus-like symptoms in mice
Authors: Luo Xin M
Published: January 2023

Gut microbiota and the immune system interact to maintain tissue homeostasis, but whether this interaction is involved in the pathogenesis of systemic lupus erythematosus (SLE) is unclear. Rheumatologists and patients have observed that antibiotics can control lupus flares, suggesting a role for pathogenic microflora in SLE. Here we report that oral antibiotics given during active disease removed harmful bacteria from the gut microbiota and attenuated lupus. Using MRL/lpr mice, we showed that antibiotics ameliorated systemic autoimmunity and kidney histopathology. They also decreased IL-17-producing cells and increased the level of circulating IL-10. In addition, antibiotics removed Lachnospiraceae and increased the relative abundance of Lactobacillus spp., two groups of bacteria previously shown to be associated with deteriorated or improved symptoms in MRL/lpr mice, respectively. Furthermore, we showed that the attenuated disease phenotype could be recapitulated with a single antibiotic vancomycin, suggesting the use of vancomycin as a potential treatment in SLE.
Correlation of alpha- and beta-specific tryptase gene expression with TPSAB1 and TPSB2 genotypes in humans
Authors: Chovanec Jack F , Liu Yihui , Bai Yun , Yin Yuzhi , Metcalfe Dean D. , Milner Joshua D. , Lyons Jonathan J.
Published: January 2023

Germline duplications or triplications of alpha-tryptase encoding sequence at TPSAB1 have been linked to elevated basal serum tryptase and are estimated to effect approximately 5% of the general population. However, no assay currently exists to quantify specific alpha- or beta-tryptase gene expression. Using a similar bioinformatic approach to what we used when designing the alpha- and beta-tryptase sequence-specific TPSAB1 genotyping assay, we developed a novel ddPCR assay able to specifically quantify alpha- and beta-tryptase gene expression. Using this assay, we then interrogated cultured primary human mast cells and isolated basophils from individuals with hereditary alpha tryptasemia syndrome – caused by increased TPSAB1 copy number – and from healthy controls. By correlating these results with individual germline TPSAB1 and TPSB2 genotypes we found that, as would be predicted, increasing alpha-tryptase encoding copy number at the TPSAB1 locus correlated with higher alpha-tryptase gene expression in healthy volunteers. Similarly volunteers lacking alpha-trytpase sequence at TPSAB1 were not detected to have alpha-tryptase gene expression, confirming the specificity of the assay. However, among individuals harboring extra TPSAB1 copies, alpha-tryptase gene expression levels were several orders of magnitude higher than beta tryptases, even when they were present in allelic balance (e.g. 3,3). These data suggest that elevated basal serum tryptase levels seen in hereditary alpha tryptasemia result predominantly from deregulated alpha-trypase gene expression, likely due to co-inheritance of as yet unidentified enhancer or promoter elements.
RELA/p65 Haploinsufficiency as a Novel Cause of Primary Immune Disorder
Authors: Faruqi Aiman J , Comrie William A , Lenardo Michael , Su Helen , Zhang Yu
Published: January 2023

Autoimmune lymphoproliferative syndrome (ALPS) is a primary immune disorder most commonly characterized by defective lymphocyte apoptosis. ALPS patients classically present with chronic non-malignant lymphadenopathy and/or splenomegaly and typically exhibit defects in FAS signaling. We identified an ALPS-like patient with normal FAS-mediated apoptosis. Whole exome sequencing identified a de novo nonsense mutation in one allele of the NF-κB subunit RELA/p65. NF-κB is a ubiquitous and rapid-acting family of transcription factors whose signaling has been implicated in numerous physiological processes including inflammatory responses, innate immunity, lymphocyte homeostasis, lymphoid organogenesis, and immune tolerance. We found the patient mutation resulted in reduced expression of p65; enhanced T cell effector responses; reduced FOXP3 expression and iTreg formation; and an over-representation of p65:p50 heterodimers in CD4+ T cells compared to normal controls. These observations, coupled with the previously demonstrated importance of NF-κB in establishing and maintaining lymphocyte homeostasis and immune tolerance, lead us to posit RELA/p65 haploinsufficiency as a novel cause of ALPS-like disease.
Germline hypomorphic, dominant interfering CARD11 mutations drive severe atopic disease
Authors: Snow Andrew L , Ma Chi , Stinson Jeffrey R , Zhang Yuan , Abbott Jordan K , Weinrich Michael A , Hauk Pia J , Reynolds Paul R , Lyons Jonathan J , Nelson Celeste G , Ruffo Elisa , Dorjbal Batsukh , Glauzy Salome , Stoddard Jennifer , Niemela Julie , Rosenzweig Sergio D , McElwee Joshua J , DiMaggio Thomas , Stone Kelly D , Palma Alejandro , Oleastro Matias , Prieto Emma , Bernasconi Andrea R , Dubra Geronimo , Danielian Silvia , Zaiat Jonathan , Marti Marcello A , Kim Brian S , Cooper Megan A , Romberg Neil , Meffre Eric , Gelfand Erwin W , Milner Joshua D.
Published: January 2023

Monogenic causes for serious manifestations of common allergic disease inform our mechanistic understanding of the pathogenesis of atopy. However, infections and other syndromic phenotypes often accompany such disorders. We performed next-generation sequencing on a cohort of patients with severe atopic dermatitis with evidence of familial inheritance, regardless of comorbidities. We discovered 9 individuals from 5 families harboring distinct, novel heterozygous mutations in CARD11, a lymphocyte scaffolding protein that facilitates NF-κB and mTOR signaling following antigen receptor (AgR) engagement. Significant infections beyond the skin, and non-immunologic comorbidities, were documented in some but not all patients. Improvement of skin and infectious history were noted in the majority of the patients. Each CARD11 mutant exhibited attenuated AgR-driven signaling to NF-κB and mTORC1, and dominantly interfered with the ability of WT CARD11 to activate these pathways in transfected T cell lines. Primary patient T cells also showed defects in AgR-induced activation of NF-κB and mTORC1, which is critical for promoting Th1 and preventing Th2 responses. Impaired proliferation, mTORC1 signaling and IFN-γ production were partially rescued by supplementing with excess glutamine, which requires CARD11 for import into T cells. In contrast to B cell lymphoproliferative disease associated with gain-of-function CARD11 mutations, and severe combined immunodeficiency associated with null CARD11 mutations, our new findings indicate single hypomorphic mutations in CARD11 can cause potentially correctable cellular defects that lead to severe atopy.
Expression and splicing of Ikaros family members in murine and human thymocytes
Authors: Seng Amara , Mitchell Julie L. , Yankee Thomas M.
Published: January 2023

The Ikaros family of transcription factors consists of five highly homologous zinc-finger proteins: Ikaros, Helios, Eos, Aiolos and Pegasus. These family members can homodimerize or heterodimerize in any combination which can alter transcriptional activity. Ikaros family member function can further vary with alternative splicing that affects DNA-binding. Previous studies have demonstrated that abolishing the function of the entire Ikaros family blocks lymphocyte development. Whereas eliminating the function of one Ikaros family member results in relatively minor defects. These data indicate that multiple Ikaros family members play a role in lymphocyte development. The goal of this study was to fully characterize expression and splicing of Ikaros family members in murine and human T cell development from the CD4−CD8− double negative (DN) developmental stage to the CD4+CD8+ double positive (DP) stage. In both mice and humans, Aiolos and Ikaros mRNA levels increase during the progression of T cell development from the DN to DP stages. However, the corresponding increase in Aiolos and Ikaros protein levels was only observed in mice. Additionally, extensive alternative splicing of Ikaros and Aiolos was observed in mice, but only Ikaros was extensively spliced in humans. Helios mRNA and protein levels decreased during murine T cell development, but increased in human T cell development. These data indicate that differences in human and murine T cell development may be regulated by differences in Ikaros family member expression and splicing.
Analysis of lymphoid tissue markers in angiomatoid fibrous histiocytoma
Authors: Nomura Takashi , Kogame Toshiaki , Kabashima Kenji
Published: January 2023

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue neoplasm of uncertain differentiation. AFH is characterized by nodular distribution of ovoid and spindle cells with blood-filled cystic cavities. It is circumscribed by thick fibrous pseudo-capsule and a surrounding dense lympho-plasmacytic infiltration encompassing germinal centers. In this study, we analyzed the structure of AFH with immunohistochemistry using markers for lymphoid organogenesis.

The tumor was a circumscribed pyriform mass, composed of histiocytoid and spindle cells. The top part of the mass encompassed cribriform vasculature, which was positive for CD31, a marker for blood endothelial cells (BECs). This BEC-dominant area contained numerous lymphoid, histiocytoid, or fibroblastoid cells, which expressed CD4 (but not CD3), CD31, CXCL13, SDF-1 (CXCL12), and receptor for LTβ (LTβR). The peripheral lymph node address in (PNAd), a marker for high endothelial venules (HEVs), was positive in some vessels, where T and B cells were clustered. The bottom part of the mass was occupied with polygonal cells expressing podolanin, a marker for lymphatic epithelial cells (LECs). The whole mass was encapsulated with CD10+ fibroblast-like cells and surrounded by organized lymphoid infiltration containing T cell areas and B cell follicles with germinal centers.

Our analysis illustrates a case of AFH composed of BEC- and LEC-dominant compartments. The well-organized peritumoral lymphoid infiltration indicated that AFH may produce an environment suitable for inducing inducible skin associated lymphoid tissue (iSALT).
Influence of AIRE-dependent versus -independent tissue restricted antigen expression by medullary thymic epithelial cells on T cell tolerance
Authors: Lebel Marie-Eve , Fournier Marilaine , Melichar Heather J
Published: January 2023

Thymocytes with high reactivity to self-antigens are, in large part, rendered tolerant through a number of mechanisms including clonal deletion and diversion toward regulatory T cell fates. Medullary thymic epithelial cells (mTECs) contribute to self-tolerance via the expression of tissue restricted antigens (TRAs). AIRE is responsible for the expression of approximately one third of TRAs, whereas AIRE-independent expression of TRAs by mTECs is less well characterized. To identify differences in AIRE-dependent and -independent tolerance, we generated new transgenic mouse models expressing a modified OVA-GFP fusion protein that contains several additional, well-characterized epitopes (2W, LCMV gp33 and LCMV gp66) in an AIRE-dependant or -independent manner. These models have enabled us to characterize distinct modes of tolerance for both MHC class I and II-restricted T cells in response to model peptides directed by AIRE-dependent and -independent TRA expression. Using organotypic culture of thymic slices overlaid with antigen-specific TCR transgenic thymocytes as well as tetramer analysis of the endogenous polyclonal T cell populations, we observed both antigen expression and peptide-specific differences in thymic selection. In addition, these difference lead to distinct levels of response to pathogen challenge and we are currently investigating the cellular interactions in the thymus associated with AIRE-dependent and -independent TRA induced tolerance by two-photon microscopy. These studies will lead to a better understanding of T cell tolerance mechanisms, and, in the longer term, inform the design of improved treatments for autoimmune diseases and cancer immunotherapies.
Distinct T cell clones are deleted during the two waves of thymic negative selection
Authors: Lee S Thera , Ruscher Roland , Hogquist Kristin Ann
Published: January 2023

T cells are the central mediators of adaptive immunity and provide diverse receptors to recognize pathogens. While this diversity protects the host from a wide variety of pathogens, it comes with the potential for harmful autoreactivity. To circumvent autoimmune disease, thymocytes bearing T cell receptors (TCRs) that bind with high affinity to self-peptide/MHC are removed in a process called negative selection, while cells with a low degree of affinity mature into conventional T cells. Recently, it has been shown that the process of negative selection occurs in two stages during thymocyte development, corresponding to medullary or cortical localization in the thymus. Little is known about the self-antigens that are presented and selected against in these locations, and thereby the corresponding T cell repertoires. We examined the T cell repertoires of these two deletion stages by sequencing thymocyte TCRs from mice with impaired negative selection (Bim−/−). These mice were crossed with transgenic Nur77GFP mice, in which GFP expression correlates with TCR signaling strength. Therefore, the rescued autoreactive clones can be identified in Bim deficient mice based on high GFP expression. The two pools of autoreactive clones – CD4+CD8+ double positive thymocytes (largely cortical and CCR7−) and CD4+ single positive thymocytes (predominantly medullary and CCR7+) – had only partially overlapping TCR sequences. As deletion selectively pruned clones, these observations indicate that thymocytes encounter different self-peptide/MHC molecules in the thymic cortex and thymic medulla. To further test if negative selection is TCR intrinsic, we are creating ‘retrogenic’ mice with auto-reactive TCRs identified from each wave.
Aberrant generation and function of natural killer T (NKT) cell in absence of Utx and Jmjd3
Authors: Wang Jie , Wu Xiaojun , Bosselut Remy , Zhou Li , Mi Qing-Sheng
Published: January 2023

Histone H3 lysine 27 trimethylation (H3K27Me3) demethylases Jmjd3 and Utx, the epigenetic regulators, affects transcription and cell differentiation. But their specific roles in invariant natural killer T (NKT) cells development, maturation and function remain to be explored. Using T cell-specific Utx and Jmjd3 double knock out (DKO) mouse model, we identified that Utx and Jmjd3 deletion results in profound impairment in NKT numbers and maturation of both thymic and peripheral immune organs. DKO thymus NKT cells showed dramatic blockade of maturation at stage 0 and stage 1. Defective expression of Slamf1 (CD150) in DKO CD69+DP thymocytes was identified, suggesting an interrupted DP selecting process. Additionally, we found the impaired expression of PLZF, Tbet, ICOS in DKO NKT cells, which is consistent with the defective NKT sublineage development in those mice. Furthermore, DKO iNKT cells showed significantly defective IFN-r, IL-4 and IL-17 production upon activation. Bone marrow chimera experiment confirmed the major defects of NKT cell development, maturation and function in DKO mice are cell autonomous. Altogether, our present study demonstrates critical contribution of Utx and Jmjd3 in NKT cell development, lineage differentiation and function. Utx and Jmjd3 related epigenetic landscape and gene expression network involved in NKT cell development and function regulation are currently under investigation.
A Long Noncoding RNA, lncRNA205, and an Embedded MicroRNA, MiR-205 have Overlapping and Distinct Contributions to Thymopoiesis and Development
Authors: van Oers Nicolai S , Hoover Ashley R , Du Qiumei , Dozmorov Igor , Raj Prithvi , de la Morena M Teresa , Cleaver Ondine B
Published: January 2023

MiR-205 is an epithelial-specific microRNA (miR) that supports thymopoiesis. This miR positively regulates Forkhead Box N1 (Foxn1) transcription factor expression. MiR-205 is embedded in a long noncoding RNA (lncRNA), termed MIR205HG in humans. Several lncRNAs that contain miRs have independent functional roles in tissue development and/or regeneration. We characterized the transcriptome assembly of the murine locus containing miR-205 and the larger lncRNA. Conditional knockout mice that harbored a targeted deletion of the proximal region of the lncRNA, with miR-205 sequences retained, were developed. The phenotypes in these mice were compared to those with a miR-205 deficiency. The more severe stress-induced thymic atrophy reported in miR-205-deficient mice, compared to littermate controls, is also evident in lncRNA205 knockout lines. In contrast, a lncRNA205 deficiency results in a smaller mouse stature, which may be coupled with a reduced fat but normal lean mass. These phenotypic differences are explained, in part, by the differential regulation of the lncRNA transcript relative to the pre-mature miR-205. Interferon and IL-22, cytokines released following inflammation, transiently reduce miR-205 while increasing the lncRNA. This is partly determined by the DNp63 transcription factor, which controls miR-205 expression. Gene expression comparisons are being undertaken to reveal how the transcriptome is differentially regulated by these two non-coding RNA species. Further, the mechanism by which these noncoding RNAs regulate Foxn1 is being elucidated. Taken together, these findings suggest both overlapping and independent functions for the lncRNA205 and the embedded miR-205.
HDAC3 is required to suppress the CD8-lineage program in DP thymocytes for CD4-lineage T cell commitment
Authors: Philips Rachael Laura , Lee Jeong-Heon , Gaonkar Krutika , Chung Ji Young , Arocha Sinibaldo Romero , Ordog Tamas , Shapiro Virginia
Published: January 2023

MHC-restricted CD4 and CD8 T cells are vital components of the immune system. The decision to generate CD4 or CD8 T cells occurs in the thymus. After positive selection, intermediate thymocytes downregulate CD8 to test coreceptor specificity. Thymocytes develop into CD4 T cells if they experience persistent TCR signaling, while termination of TCR signaling leads to IL-7-mediated CD8-lineage commitment via Runx3. While the general signaling and transcriptional mechanisms are known, the epigenetic mechanisms controlling error-free lineage commitment are largely unknown. We found histone deacetylase 3 (HDAC3) to be critical for generating CD4 T cells, as its deletion leads to the generation of only CD8SP cells. Introduction of an OT-II TCR transgene revealed redirection of MHC class II-restricted cells to the CD8 lineage upon HDAC3 deletion. We found evidence that HDAC3-deficient DP thymocytes are primed for the CD8-lineage, as they exhibit hyperacetylation at CD8-lineage promoting genes and show elevated expression of phosphorylated-STAT5 (pSTAT5). During lineage choice, OT-II expressing HDAC3-deficient cells inappropriately upregulate Runx3. Therefore, HDAC3 functions as a brake in DP thymocytes whose release leads to a developmental bias for CD8 T cells.
The non-receptor protein tyrosine kinase Pyk2 promotes the turnover of mouse monocyte populations at steady-state
Authors: Llewellyn Ryan , Thomas Keena S. , Bouton Amy H
Published: January 2023

Peripheral monocytes, consisting of distinct Ly6C+ and Ly6Cneg subsets in mice, are innate immune effector cells that exhibit a relatively short half-life of 1–3 days. While the differentiation and function of these monocyte subpopulations have been explored extensively, the cellular mechanisms regulating the maintenance and turnover of these populations are not completely understood. The focus of our current study is to investigate the role of proline-rich tyrosine kinase 2 (Pyk2) in the establishment and/or maintenance of monocyte populations at steady-state.

Using a Pyk2 knock-out mouse model (Pyk2−/−), we show for the first time that Pyk2−/− mice exhibit reduced bone marrow (BM) cellularity, resulting in a reduction of total BM monocytes in these mice. Accordingly, Pyk2−/− mice display reduced numbers of BM monocyte progenitors and Ly6C+ monocytes; however, there is no reduction in the representation of Ly6Cneg monocytes in the absence of Pyk2, suggesting that Pyk2 regulates the relative proportion of monocyte subsets normally represented in the BM at steady state. In support of this conclusion, a similar phenotype was observed in the peripheral blood and spleen. Data from reciprocal and mixed BM chimera experiments indicate that the alterations in monocyte populations exhibited by Pyk2−/− mice are due to factors intrinsic to the monocytes. Pyk2 does not appear to regulate the proliferation, differentiation, or egress of monocyte subsets. Instead, experiments using annexin V and cleaved caspase as markers for apoptosis indicate that Pyk2 may promote apoptosis in BM monocytes, thereby acting as an important regulator of turnover in these short-lived effector cells.
Transcription factor IRF8 governs enhancer landscape dynamics during mononuclear phagocyte development
Authors: Kurotaki Daisuke , Nakabayashi Jun , Nishiyama Akira , Sasaki Haruka , Kaneko Naofumi , Kawase Wataru , Ozato Keiko , Suzuki Yutaka , Tamura Tomohiko
Published: January 2023

Monocytes and dendritic cells (DCs) are mononuclear phagocytes essential for innate and adaptive immunity. These phagocytes develop from hematopoietic stem cells via intermediate progenitors, such as granulocyte-monocyte progenitors (GMPs), monocyte-DC progenitors (MDPs), and common monocyte progenitors (cMoPs) or common DC progenitors (CDPs). However, the molecular mechanism underlying their differentiation potential remains incompletely understood. Recent studies suggest that promoter-distal enhancers are key for cell fate decision. In this study, we performed chromatin immunoprecipitation-sequencing (ChIP-seq) analysis of enhancer-related histone modifications in GMPs, MDPs, cMoPs, CDPs, monocytes, DCs, and neutrophils. We found that monocyte- and DC-specific enhancers were gradually established at progenitor stages before the expression of associated genes. Of the transcription factors predicted to bind to these enhancers, IRF8, essential for monocyte and DC development, was found to be required for the establishment of these enhancers, particularly those common to both monocyte and DC lineages. Somewhat unexpectedly, global gene expression patterns were comparable between the remaining Irf8−/− progenitors and their wild-type counterparts. Nevertheless, the enhancer landscapes of Irf8−/− progenitors were significantly distinct from those of wild-type cells, with the enhancer landscapes of Irf8−/− GMPs, MDPs, and cMoPs all remaining similar to that of wild-type GMPs. Our results illustrate the dynamic process by which key transcription factors regulate enhancer formation and thereby direct future gene expression to achieve mononuclear phagocyte development.
Analysis of the Anaphylactic and Immune Reactions by Means of the Isolated Guinea-Pig Lungs
Authors: Manwaring W. H. , Kusama Yoshio
Published: January 2023

Analyses of the anaphylactic and immune reactions by means of perfusion experiments with the isolated guinea-pig lungs show that we are here concerned with three essential factors: Cellular hypersensitiveness, or the anaphylactic response of the hypersensitive fixed pulmonary tissues,Humoral anaphylaxis, or the chemical response (anaphylotoxin formation) of the anaphylactic blood, andHumoral immunity, or the inhibiting or protecting action of the immune blood.

In the 14-day anaphylactic guinea-pig, the fatal bronchial spasm is due, in part to fixed cellular hypersensitiveness, in part to humoral anaphylaxis.

In the 4-week anaphylactic guinea-pig, the fixed cellular hypersensitiveness is usually greater than that of the 14-day anaphylactic guinea-pig. The humoral reaction, however, is usually absent. The fatal bronchial spasm in the 4-week anaphylactic guinea-pig is usually due solely to fixed cellular hypersensitiveness.

The immune guinea-pig usually shows a fixed cellular hypersensitiveness greater than that of the 14-day anaphylactic guinea pig. A fatal bronchial spasm is prevented in the immune guinea-pig, however, by the inhibiting or protecting action of the immune blood.

The immune guinea-pig, therefore, shows a seemingly paradoxical phenomenon, the coexistence of a fixed cellular hypersensitiveness and a humoral immunity.
Experiments with a Possible Bearing Upon Treatment of Typhoid Fever with Typhoid Vaccine Administered Intravenously
Authors: Teague Oscar , McWilliams Helen I.
Published: January 2023

Summary and Discussion

The intravenous injection of a suitable dose of killed typhoid bacilli in rabbits causes within twenty-four hours a refractory state, which enables them to withstand a dose of living typhoid bacilli that is fatal to normal rabbits. Since antibodies are not demonstrable until four or five days after an injection of antigen, this is not a process of immunization in the accepted sense of the term.

This sudden increase in resistance to living typhoid bacilli bears a certain resemblance to the cure of typhoid fever patients by crisis following the intravenous injection of typhoid vaccine, the reaction in both instances occurring in about twenty-four hours after the injection of the vaccine, which is followed in both cases by a rapid and often extremely high rise in temperature. This suggests that the same factor or factors may be concerned in the two phenomena.

In the preceding article it was shown that the injection of the doses of vaccine used in these experiments does not increase the bacteriolytic power of normal rabbit serum; hence the increased resistance in the treated rabbits is not due to this factor. Nor is it due to an increase in the number of leucocytes in the peripheral blood resulting from the preliminary injection of vaccine; for rabbits that do not show the leucocytosis are also refractory.

The bacteria disappear from the peripheral blood only slightly more rapidly in the treated than in the control animals, there being a rapid decrease in both normal and treated rabbits during the first hour. In the treated animals this decrease continues progressively until the bacteria are very scarce; in the normal controls it appears to be followed by an increase for a short time and then a rapid decrease until the bacteria are very scarce as in the treated rabbits. The cause of this difference in the normal and treated rabbits is not clear but the evidence at hand indicates that it is not due to an increase of the bacteriolytic power of the blood plasma of the treated rabbits.

For the present we wish merely to record the fact that a rabbit becomes more resistant to infection with typhoid bacilli within 24 hours after the intravenous injection of typhoid vaccine and to point out a possible relationship between the phenomenon and the cure of typhoid fever patients by means of the intravenous injection of typhoid vaccine, without attempting to set up any hypothesis as to the mechanism of the process.
The Bacteriolytic Power of Normal Human Sera and Typhoid Patients' Sera for Typhoid Bacilli and an Inquiry Into the Theoretical Basis for the Treatment of Typhoid Fever with Vaccine Administered Intravenously
Authors: Teague Oscar , McWilliams Helen I.
Published: January 2023

The bacteriolytic action of the sera of typhoid patients has been studied extensively by two methods: first, by determining the greatest dilution of the serum that will kill a given dose of typhoid bacilli and secondly, by determining the greatest dilution of the serum that, with the addition of rabbit or guinea pig complement, will kill a given dose of typhoid bacilli. By both of these methods the titers of the patients' sera were found to be higher than those of normal human sera; with the addition of complement the patients' sera sometimes killed typhoid bacilli at a dilution of 1/500,000 or even 1/1,000,000. Korte and Steinberg (1) say that the (bacteriolytic) amboceptor content of the serum rises during the first weeks of the disease and falls towards convalescence. Denison (2) obtained similar results. The latter found that complement remains constant throughout the disease no matter what spectacular increase or decrease the immune bodies might show.
Hay Fever
Authors: Cooke Robert A. , Flood Edward P. , Coca Arthur F.
Published: January 2023

Since the etiological relation of the pollens of certain plants to hay fever and some forms of asthma was established, a number of investigators have studied the question of the nature of the active substances in the pollens, as well as the mechanism of the curative or alleviating effect of the two forms of specific treatment (with “antitoxin”—“pollantin” of Dunbar—and with active immunization as first practised by Noon).

Originally, both of these methods of treatment were based upon the assumption that the active substances of the pollens are toxins (toxalbumins) to which the former method induced a passive immunization, while the latter, as already indicated, caused an active immunization by the production of specific antibodies.

This conception has been supplanted by the theory of Wolff-Eisner (1),1 according to which the clinical manifestations of hay fever are expressions of hypersensitiveness to an otherwise non-toxic constituent of the pollens.
Serum LTB4, HODE13 and PLA2G7 as biomarkers of cardiovascular disease in SLE
Authors: Baig Sahar , Ding Huihua , McMahon Maureen , Mohan Chandra
Published: January 2023

Background

Cardiovascular complications are the most serious ones associated with lupus, and are thought to be caused by inflammation which results from autoimmunity. This study uses a metabolomic screen to identify metabolites that are elevated in SLE patients with and without CVD. Four of metabolites elevated in the initial screen have been selected for validation by ELISA.

Methods

27 serum samples (10 healthy controls, 8 with SLE and plaque progression, 9 with SLE and no plaque progression) were screened for elevated metabolites. Four of the most significantly elevated metabolites were selected for validation in another cohort of 85 serum samples (25 healthy controls, 53 with lupus nephritis, 7 with both lupus nephritis and cardiovascular disease).

Results

Metabolomic screening of the initial cohort demonstrated that several lipoxygenase metabolites (and HODE 13) were elevated in SLE patients who developed CVD compared to other SLE patients (p < .05) and healthy controls (p < .05). Based on this, LOX15, LTB4, and PLA2G7 (as well as HODE13) were selected for ELISA validation. Serum PLA2G7 correlated positively with number and increase of atherosclerotic plaques, as well as smoking history (p<.05 and <.01, respectively). LTB4 correlated positively with coronary artery disease (p<.05) and HODE13 correlated positively with hypertension and SLEDAI (p<.05).

Conclusions

Serum LTB4, HODE13 and PLA2G7 exhibit potential as biomarkers distinguishing between SLE patients who are or are not at risk of developing cardiovascular complications. Longitudinal studies are in progress to assess the clinical utility of these novel markers.
Identification of protein biomarkers in cerebrospinal fluid(CSF) of Neuro Psychiatric SLE(NPSLE) patients using SOMA scan assay.
Authors: Vanarsa Kamala , Hanly John , Mok C.C. , Mohan Chandra
Published: January 2023

Background

Neurological manifestations of systemic lupus erythematosus (NPSLE) include a wide spectrum of symptoms like seizures, meningitis and psychosis. Clinical diagnosis of NPSLE is challenging due to the lack of objective diagnostic tests. Here, we explore if CSF proteins may have diagnostic value in NPSLE.

Methods

24 CSF samples (8 healthy + 8 neuro controls (NC) + 8 NPSLE) were screened using an aptamer-based platform for about 1100 proteins. A subset of the differentially expressed CSF proteins was selected for validation in two different cohorts, Caucasian controls (N=54) & NPSLE (N= 25) and Chinese controls (N=15) & SLE (N= 17).

Results

The initial aptamer-based screen revealed 8 CSF proteins to be elevated in NPSLE vs healthy, at fold change >2, and p <0.05. All 8 proteins were validated by ELISA. Total IgM, Lipocalin 2, M-CSF were significantly elevated in the CSF of NPSLE when compared to controls, in both Caucasian and Chinese patients (range of fold change: 16–1.2; p < 0.05). CSF HCC-s, DAN and Angiostatin were significantly elevated in Caucasian NPSLE patients only (range of fold change: 2.3–1.8; p < 0.05). Total C3 and albumin in CSF did not show any difference in disease groups in both cohorts, as assayed by ELISA.

Conclusion

Several novel proteins were noted to be elevated in NPSLE CSF, relative to control subjects with other neurological symptoms. Further studies are warranted to establish the specificity of CSF IgM, Lipocalin 2, M-CSF, HCC-s, DAN and Angiostatin for NPSLE and to understand their pathogenic relevance.
Neuropsychiatric lupus is lipocalin-2 dependent
Authors: Mike Elise V. , Cuda Carla , Makinde Hadijat , Perlman Harris , Putterman Chaim
Published: January 2023

Neuropsychiatric manifestations of systemic lupus erythematosus (NPSLE) affect approximately 40% of patients. Lipocalin-2 (LCN2), an acute-phase reactant protein, is an established urinary biomarker in lupus patients. Previous studies using LCN2-deficient mice have demonstrated its role in glial migration and chemokine regulation in the brain. We therefore hypothesized that LCN2 is involved in NPSLE pathogenesis. We investigated the lupus prone B6.Sle1.Sle3 (Sle1,3) mouse and the effects of LCN2 deficiency on the development of the neuropsychiatric phenotype exhibited by this strain. Sle1,3, B6.LCN2KO, B6, and Sle1,3-LCN2KO mice (6–10 month old; n=5–10/group) underwent comprehensive neurobehavioral assessment, and brains were evaluated by flow cytometry and RNA sequencing.

Sle1,3 mice exhibited significant impairment in spatial (p<0.04) and recognition (p<0.02) memory when compared with B6 mice, and these deficits were attenuated in Sle1,3-LCN2KO mice (p<0.001, p<0.02). Furthermore, Sle1,3 mice demonstrated anhedonia, and this depression-like behavior was significantly reduced with LCN2 deficiency (p=0.01). Flow cytometry showed a significant increase in brain infiltrating CD8+ T cells in Sle1,3 mice, with a reduction in infiltration in the Sle1,3-LCN2KO strain (p=0.06). Preliminary analysis of RNA sequencing from sorted microglia revealed genes involved in cognition and memory that were differentially expressed in Sle1,3 mice were restored to background B6 expression levels in Sle1,3-LCN2KO mice.

Our findings establish the Sle1,3 mouse as an NPSLE model and demonstrate that LCN2 deficiency attenuates neurobehavioral deficits and regulates microglial expression of genes essential to NPSLE development.
Loss of circadian rhythmicity of renin-angiotensin-aldosterone system and sodium and potassium balance in lupus nephritis mice
Authors: Mishra Rakesh K. , Bethunaickan Ramalingam , Zhang Weijia , Davidson Anne
Published: January 2023

Background

The mammalian circadian system regulates numerous physiological processes including immune responses. We found a disturbance of expression of key clock transcriptional regulators in the kidneys of mice with SLE nephritis. The purpose of this study was to determine how this abnormality affected transcriptional regulation of renally expressed genes and immune cell homeostasis.

Methods

We studied NZB/W mice at the age of 12 weeks (without proteinuria) and >30 weeks (with proteinuria). Kidneys, urine and blood were harvested at 4 hour intervals. Kidneys were perfused with PBS and used to generate RNA and single cells for flow cytometry analysis. Blood pressure was measured by the tail-cuff method. Urine Na and K were measured by Charles River Lab. Blood and urine aldosterone was measured by ELISA.

Results

Kidneys of young mice displayed a normal circadian pattern of expression of the master transcriptional regulators of circadian rhythm including Bmal1, Clock, Per and Cry. By contrast, the nephritic mice had attenuated rhythm of these genes with dampened BMAL1 expression. To investigate whether timed regulation of renal function was disrupted SLE nephritis mice we compared urinary Na and K excretion during the night versus the day. Young mice exhibited significant day/night differences in urinary Na and K. In contrast, SLE mice did not exhibit a day/night difference in urinary Na and K. In parallel, SLE mice lost the normal circadian rhythm of plasma aldosterone levels and blood pressure with a spike in blood pressure during the day instead of at night.

Conclusion

These data show that the circadian clock mechanism is disrupted in the setting of renal inflammation resulting in dysregulation of normal renal physiologic functions.
Salivary biomarkers in SLE
Authors: Gotewal Sunny , Soomro Sanam , Akbar Umair , Saxena Ramesh , Petri Michelle , Mohan Chandra
Published: January 2023

Background

Lupus Nephritis (LN) affects close to half of all SLE patients and is currently diagnosed through kidney biopsy. In search for a noninvasive diagnostic method, four serum biomarkers of SLE (IGFBP2, sTNFRII, Axl, VCAM1) were valued for their diagnostic potential in the saliva of SLE patients.

Methods

IGFBP2, STNFRII, Axl, VCAM1 were ELISA assayed in the serum and saliva of SLE patients (16 inactive, 10 active non-renal, 10 active renal) and 14 healthy controls. Group wise analysis by Mann Whitney test and Spearman correlation analyses between serum and saliva were done.

Results

IGFBP2 was elevated in SLE serum compared to controls (FC=3.2 P=0.0002) while sTNFRII and VCAM1 showed elevation in active compared to inactive SLE (FC=2.2 P=0.002 and FC=2.8 P<0.0001 respectively). Salivary IGFBP2 and sTNFRII were elevated in SLE compared to controls (FC=2.4 P=0.01, FC=2.8 P=0.04 respectively), but was not associated with disease activity or renal involvement. Saliva and serum biomarkers did not correlate in this sample cohort.

Conclusion

Although all four biomarkers (IGFBP2, sTNFRII, Axl, VCAM1) have shown diagnostic potential in SLE serum, only IGFBP2 and sTNFRII were elevated in SLE saliva. Further exploration into other salivary biomarkers through an unbiased aptamer based protein screening platform is in progress.
Human regulatory T cells suppress CD4+ T cells by rapidly altering the phosphoproteome
Authors: Joshi Rubin Narayan , Marabita Francesco , Binai Nadine , Sui Zhenhua , Altman Amnon , Heck Albert J. , Tegner Jesper , Schmidt Angelika
Published: January 2023

Regulatory T cells (Tregs) control key events of immunity primarily by suppression of effector T cells, and Treg dysfunction is involved in the pathogenesis of autoimmunity, allergy and cancer. We previously revealed that Tregs rapidly suppress T cell receptor (TCR)-induced calcium store depletion in conventional CD4+CD25− T cells (Tcons) independently of IP3 levels, consequently inhibiting NFAT signaling and effector cytokine expression.

Here, we study Treg suppression mechanisms through unbiased phosphoproteomics of primary human Tcons upon TCR stimulation and Treg-mediated suppression, respectively. We have demonstrated that Tregs suppress the signalling cascade in Tcons by inducing a state of overall decreased phosphorylation as opposed to TCR stimulation. Further we also discovered novel phosphosites (T595_S597) in the DEF6 (SLAT) protein that were phosphorylated upon TCR stimulation and conversely dephosphorylated upon coculture with Tregs. Mutation of these DEF6 phosphosites abrogated interaction of DEF6 with the IP3 receptor and affected NFAT activation and cytokine transcription in primary Tcons. Additionally, we also discovered a phosphatase inhibitor from our phosphoproteomic screen, the loss of which rendered the Tcons to be resistant to Treg-mediated suppression.

These novel mechanisms and phosphoproteomics data resource may aid in modifying sensitivity of Tcons to Treg-mediated suppression and contribute to improve treatment of autoimmunity and cancer, particularly considering the frequently observed resistance of target Tcons to Treg-mediated suppression in human autoimmune disease.
Conditional deletion of CD25 in Tregs abrogates their suppressive function independently of Foxp3
Authors: Toomer Kevin Henry , Malek Thomas R.
Published: January 2023

IL-2R signaling is essential for thymic development and homeostasis of CD4+Foxp3+ Tregs, which are required to maintain self-tolerance. Although deletion of IL-2/IL-2R in mice leads to lethal autoimmunity, disease is delayed in comparison to mice lacking Foxp3. It is unclear whether this delay is due to redundant signaling in Tregs by other γc cytokines, or to loss of IL-2 activation of autoreactive T cells. To explore IL-2R function in Tregs, we evaluated the consequence of germline knockout (gKO) versus Treg-conditional knockout (cKO) of CD25. Both types of KO mice developed lethal systemic autoimmunity, but CD25 cKO mice exhibited a scurfy-like phenotype with a life span of 3–4 weeks, while death was delayed until 8–12 weeks in gKO mice. CD4+ and CD8+ T cells were more activated and produced higher levels of TNFα, IL-6, and IFNγ in CD25 cKO mice early in life when compared to CD25 gKO mice. This result in conjunction with normal thymic selection in both models indicates that the slower tempo of autoimmunity in CD25 gKO mice is due to impaired function of their autoreactive T cells, which does not occur in CD25 cKO mice. In addition, Foxp3 levels were only slightly reduced in thymocytes from both models, but they each showed diminished expression of Treg suppressive markers. This finding is consistent with the idea that IL-2R signaling is essential for functional programming of Tregs independent of Foxp3 expression. The effects noted above for nascent thymic Tregs in gKO mice were somewhat more striking than in cKO mice. This observation suggests another IL-2-dependent step in Treg development that is likely redundant. Overall, our data indicate that Tregs are completely non-functional without IL-2R signaling.
Treg-specific LAG3 deletion reveals a key role for LAG3 in regulatory T cells to inhibit CNS autoimmunity
Authors: Thaker Youg Raj , Andrews Lawrence P. , Workman Creg J. , Vignali Dario A. A. , Sharpe Arlene H.
Published: January 2023

The inhibitory receptor Lymphocyte activation gene 3 (LAG3; CD223) plays a key role in regulating T cell activation and tolerance. LAG3 can be expressed on CD4+ FoxP3+ regulatory T cells (Tregs) and conventional effector T cells (Tcons). We found that LAG3 is highly expressed by CD4+ FoxP3+ Tregs in the CNS of mice with experimental autoimmune encephalitis, a mouse model of multiple sclerosis, leading us to examine LAG3 function on CD4+ FoxP3+ Treg in EAE. To study LAG3 function on Tregs in EAE, we crossed mice in which LAG3 is absent on the cell surface of CD4+ FoxP3+ Tregs with 2D2 T cell receptor (TCR) transgenic specific for myelin oligodendrocyte glycoprotein (MOG35-55). Surprisingly, 100% of the 2D2 TCR transgenic mice lacking LAG3 on Tregs developed spontaneous EAE. In marked contrast, none of the 2D2 control mice developed EAE. Similarly, non-TCR transgenic mice lacking LAG3 on Tregs developed more severe induced EAE (by immunization with MOG35-55 in CFA) compared to controls (max clinical score 3.5±0.3 in LAG3 deficient vs. 2.8±0.1 in control SEM). Histological analysis revealed significantly more lesions in both brain and spinal cord of LAG3 deficient mice (mean number in spinal cord 226.5 ± 10.57 LAG3 deficient vs. 51.4 ± 40.81 in controls SEM). Ex vivo analysis at the peak of disease showed that disease severity was accompanied by an increase in the pathogenicity of Tcons producing high levels of IFN-γ and granzyme B. Although no significant differences were observed in CNS infiltration of Tregs, LAG3 deficient Tregs produced IFN-γ and granzyme B, suggesting that they are no longer protective, but instead contribute to CNS disease. These findings point to a key role for LAG3 in controlling Treg function and maintenance of tolerance in the CNS.
Early neutrophil depletion reduces inflammation-sensitized hypoxic-ischemic brain injury in mouse neonates.
Authors: Yao Hui-Wen , Kuan Chia-Yi
Published: January 2023

Hypoxia-ischemia to brain triggers immune responses consisting of activation and recruitment of leukocytes and expression of pro-inflammatory mediators. Inducing neutropenia confers protection against cerebral ischemia in adult and neonatal rats, but it remains unclear if neutrophils enhances neonatal brain damage in inflammation (LPS)-sensitized hypoxic-ischemic (HI) insults to mice. Herein, we demonstrated that following LPS/HI insult, the mRNA expression of C-X-C motif ligands 1 and 2, two potent neutrophil chemoattractants, granulocyte colony-stimulating factor that stimulates the bone marrow to produce and release granulocytes, and pro-inflammatory cytokines, including interleukins 1β and 6 and tumor necrosis factor α, were increased in mouse brains. As early as six hours after insult, neutrophil infiltration was readily detectable in mouse brains and increased with time, especially in those brains with severe damage. Neutrophils either resided within vessel like structures or accumulated within brain parenchyma. In addition, infiltrated neutrophils expressed interleukin 1β and tumor necrosis factor α, as well as citrullinated histones, a marker of neutrophil extracellular traps, in the damaged brains. Importantly, prophylactic depletion of neutrophils from the periphery reduced leukocyte infiltration, the expression of pro-inflammatory mediators in mouse brains, and brain atrophy, whereas post-insult depletion of neutrophils conferred marginal protection. Collectively, our data support the pathogenic roles of neutrophils in the acute phase of inflammation-sensitized hypoxia-ischemia brain injury.