In vivo neutralization of TNF-alpha promotes humoral autoimmunity by preventing the induction of CTL

Sex differences in donor T cell targeting of host splenocyte subpopulations in acute and chronic murine graft-vs.-host disease: implications for lupus-like autoimmunity

This study sought to compare in vivo sex differences in either a Th1-dominant CTL response or a Tfh-mediated lupus-like antibody response using the parent-into F1 murine model of acute or chronic GVHD respectively. In acute GVHD we observed no significant sex differences in the hierarchy of donor CD8 CTL elimination of splenocyte subsets. B cells were the most sensitive to elimination in both sexes; however, the male response was significantly stronger. Sex differences in chronic GVHD were more widespread; females exhibited significantly greater numbers of total splenocytes and host CD4 Tfh cells, B cells and CD8 T cells consistent with reports of greater female autoantibody production in this model. The more potent male CTL response in acute GVHD conflicts with reports of greater female CTL responses following infections or vaccines and may reflect the absence of exogenous innate immune stimuli in this model.

Past, Present and (Foreseeable) Future of Biological Anti-TNF Alpha Therapy

Due to the key role of tumor necrosis factor-alpha (TNF-α) in the pathogenesis of immunoinflammatory diseases, TNF-α inhibitors have been successfully developed and used in the clinical treatment of autoimmune disorders. Currently, five anti-TNF-α drugs have been approved: infliximab, adalimumab, golimumab, certolizumab pegol and etanercept. Anti-TNF-α biosimilars are also available for clinical use. Here, we will review the historical development as well as the present and potential future applications of anti-TNF-α therapies, which have led to major improvements for patients with several autoimmune diseases, such as rheumatoid arthritis (RA), ankylosing spondylitis (AS), Crohn's disease (CD), ulcerative colitis (UC), psoriasis (PS) and chronic endogenous uveitis. Other therapeutic areas are under evaluation, including viral infections, e.g., COVID-19, as well as chronic neuropsychiatric disorders and certain forms of cancer. The search for biomarkers able to predict responsiveness to anti-TNF-α drugs is also discussed.

Advancing Biologic Therapy for Refractory Autoimmune Hepatitis

Biologic agents may satisfy an unmet clinical need for treatment of refractory autoimmune hepatitis. The goals of this review are to present the types and results of biologic therapy for refractory autoimmune hepatitis, indicate opportunities to improve and expand biologic treatment, and encourage comparative clinical trials. English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Rituximab (monoclonal antibodies against CD20 on B cells), infliximab (monoclonal antibodies against tumor necrosis factor-alpha), low-dose recombinant interleukin 2 (regulatory T cell promoter), and belimumab (monoclonal antibodies against B cell activating factor) have induced laboratory improvement in small cohorts with refractory autoimmune hepatitis. Ianalumab (monoclonal antibodies against the receptor for B cell activating factor) is in clinical trial. These agents target critical pathogenic pathways, but they may also have serious side effects. Blockade of the B cell activating factor or its receptors may disrupt pivotal B and T cell responses, and recombinant interleukin 2 complexed with certain interleukin 2 antibodies may selectively expand the regulatory T cell population. A proliferation-inducing ligand that enhances T cell proliferation and survival is an unevaluated, potentially pivotal, therapeutic target. Fully human antibodies, expanded target options, improved targeting precision, more effective delivery systems, and biosimilar agents promise to improve efficacy, safety, and accessibility. In conclusion, biologic agents target key pathogenic pathways in autoimmune hepatitis, and early experiences in refractory disease encourage clarification of the preferred target, rigorous clinical trial, and comparative evaluations.

The incidence, clinical characteristics and serological characteristics of anti-tumor necrosis factor-induced lupus in patients with inflammatory bowel disease: A systematic review and meta-analysis

BACKGROUND

There are concerns regarding anti-TNF-induced lupus (ATIL) in patients with inflammatory bowel disease (IBD). We performed a systematic review and meta-analysis about the incidence, the clinical characteristics and serological characteristics of ATIL secondary to anti-TNF agents in IBD patients.

METHODS

Electronic databases were searched to identify relevant studies. Primary outcomes were the pooled ATIL incidence rates in IBD patients treated with anti-TNF agents. Secondary outcomes were the pooled clinical symptoms incidence rates, autoantibodies incidence rates and clinical resolution rates in IBD patients treated with anti-TNF agents.

RESULTS

Ten studies were included in this meta-analysis. The pooled ATIL incidence rate in IBD patients treated with anti-TNF-α agents was 2.5%. The pooled ATIL incidence rate in UC and CD patients treated with anti-TNF-α agents was 1.5% and 1.8%, respectively. The pooled ATIL incidence rate in IBD patients treated with IFX and ADA was 4.5% and 0.2%, respectively. The pooled arthritis, mucocutaneous symptom, myalgia and fatigue incidence rate in IBD patients treated with anti-TNF-α agents was 87.2%, 29.4%, 23.9% and 41.8%, respectively. The pooled ANA rate in IBD patients treated with anti-TNF-α agents was 97.3%. The pooled anti-dsDNA antibody rate in IBD patients treated with anti-TNF-α agents was 73.9%.

CONCLUSION

ATIL has a low prevalence in IBD patients treated with anti-TNF agents. ATIL occurs more frequently in CD patients than in UC patients. Arthritis, fatigue and mucocutaneous lesions were found to be common symptoms of ATIL. Patients with ATIL were more likely to develop ANA and anti-dsDNA.

Targeting TNFα produced by astrocytes expressing amyotrophic lateral sclerosis-linked mutant fused in sarcoma prevents neurodegeneration and motor dysfunction in mice

Genetic mutations that cause amyotrophic lateral sclerosis (ALS), a progressively lethal motor neuron disease, are commonly found in ubiquitously expressed genes. In addition to direct defects within motor neurons, growing evidence suggests that dysfunction of non-neuronal cells is also an important driver of disease. Previously, we demonstrated that mutations in DNA/RNA binding protein fused in sarcoma (FUS) induce neurotoxic phenotypes in astrocytes in vitro, via activation of the NF-κB pathway and release of pro-inflammatory cytokine TNFα. Here, we developed an intraspinal cord injection model to test whether astrocyte-specific expression of ALS-causative FUSR521G variant (mtFUS) causes neuronal damage in vivo. We show that restricted expression of mtFUS in astrocytes is sufficient to induce death of spinal motor neurons leading to motor deficits through upregulation of TNFα. We further demonstrate that TNFα is a key toxic molecule as expression of mtFUS in TNFα knockout animals does not induce pathogenic changes. Accordingly, in mtFUS-transduced animals, administration of TNFα neutralizing antibodies prevents neurodegeneration and motor dysfunction. Together, these studies strengthen evidence that astrocytes contribute to disease in ALS and establish, for the first time, that FUS-ALS astrocytes induce pathogenic changes to motor neurons in vivo. Our work identifies TNFα as the critical driver of mtFUS-astrocytic toxicity and demonstrates therapeutic success of targeting TNFα to attenuate motor neuron dysfunction and death. Ultimately, through defining and subsequently targeting this toxic mechanism, we provide a viable FUS-ALS specific therapeutic strategy, which may also be applicable to sporadic ALS where FUS activity and cellular localization are frequently perturbed.

Pathogenesis of Paradoxical Reactions Associated with Targeted Biologic Agents for Inflammatory Skin Diseases

Targeted biologic agents have dramatically changed the therapeutic landscape for immune-mediated inflammatory diseases, particularly in rheumatology and dermatology. Their introduction has resulted in a paradigm shift, i.e., they produce significant clinical improvements in most patients with such diseases. Nevertheless, a variety of adverse reactions associated with these agents have been observed, including so-called paradoxical reactions (PRs), which are a new class of adverse events. PRs involve the de novo development or worsening of immune-mediated inflammatory disease during treatment with a targeted biologic agent that is commonly used to treat the idiopathic counterpart of the drug-induced reaction. In addition, the efficacy of biologic agents targeting individual cytokines and the existence of PRs to them have provided proof that cytokines are key drivers of various immune-mediated inflammatory diseases and helped researchers elucidate the molecular pathways underlying the pathophysiology of these diseases. Here, a comprehensive review of the targeted biologic agents used to treat immune-mediated inflammatory diseases, particularly psoriasis and atopic dermatitis, is provided, with a specific focus on biologic agents that inhibit cytokine signaling involving tumor necrosis factor-α, interleukin (IL)-12/23 (p40), IL-17A (and the IL-17 receptor [R]), IL-23 (p19), and the IL-4Rα, and their associated PRs. The characteristic clinical manifestations and potential immunological mechanisms of the PRs induced by these biologic agents are also reviewed.

Bullous pemphigoid induced by biologic drugs in psoriasis: a systematic review

INTRODUCTION

Several therapies for psoriasis have been described as triggers of biologic-induced bullous pemphigoid (BIBP). The real incidence of BIBP in psoriatic patients is still unknown. Hence, we compilated and analyzed current literature to identify the frequency and burden of this adverse event for psoriasis patients treated with biologics.

MATERIAL AND METHOD

We systematically searched literature records involving psoriatic patients developing BIBP. Electronic searches were conducted in Pubmed, EMBASE and Scopus in April 2021. To assess the causal relationship between BP and the biologic drug, we applied the Naranjo adverse reaction probability scale and the Karch-Lasagna algorithm.

RESULTS

Our systematic review identified 586 records through the three electronic databases. We identified 15 case reports of BIBP. These cases implicated two cases induced by adalimumab, three by efalizumab, three by etanercept, six by ustekinumab, and one case by secukinumab. Mean period of latency until the BIBP developed was time 5.12 ± 3.44 weeks for TNF-α blockers, and 28.66 ± 26.27 weeks for ustekinumab (p = .09). Most of the cases were assessed as "probable" consistently in both the Naranjo scale and the Karch-Lasagna algorithm.

CONCLUSION

This work presents an accurate estimation on the frequency and burden of BIBP. Ustekinumab presents with the largest evidence of BIBP, especially in patients with previous failure to TNF-α agents. Distinct patterns in the cytokinic pathways and clinical course exist between the BP induced by TNF-α blockers and ustekinumab. A close monitoring of skin condition is highly advisable in patients receiving biologic therapies for psoriasis. Knowledge of BIBP is of great importance to determine the preventive measures and select optimal treatment options.What's already known about this topic?The widespread use of biologic drugs has led dermatologists to encounter increasing situations of biologic-induced BP (BIBP).A lack of data exists on the real incidence of BIBP in psoriatic patients.BIBP is an important adverse event to know when managing patients with psoriasis using biologics.What does this study add?This work presents an accurate estimation on the raised burden of BIBP.Ustekinumab presents with the largest evidence of BIBP, especially in patients with previous failure to TNF-α agents.Mean period of latency until the BIBP developed was time 5.12 ± 3.44 weeks for TNF-α blockers, and 28.66 ± 26.27 weeks for ustekinumab.Distinct patterns in the cytokine pathways and clinical course exist between the BP induced by TNF-α blockers and ustekinumab.A careful screening of previous history of bullous diseases and a baseline immunologic study in psoriatic patients should be advisable prior to commencing any biologic therapy.A close monitoring of skin condition is highly advisable in patients receiving biologic therapies for psoriasis.

A MLR-Based Approach to Analyze Regulators of T Lymphocyte Activation In Vivo

Depending on the context, robust and durable T lymphocyte activation is either desirable, as in the case of anti-tumor responses, or unwanted, in cases of autoimmunity when chronic stimulation leads to self-tissue damage. Therefore, reliable in vivo models are of great importance to identify and validate regulatory pathways of T lymphocyte activation. Here, we describe an in vivo mixed-lymphocyte-reaction (MLR) approach, which is based on the so-called parent-into-F1 (P → F1) mouse model in combination with the congenic marker CD45.1/2 and cell proliferation dye-labeling. This setup allows us to track adoptively transferred allogenic CD4+ and CD8+ T lymphocytes and analyze their phenotype as well as the proliferation by flow cytometry in the blood and spleen. We could show hypo-reactive responses of T lymphocytes isolated from knockout mice with a known defect in T lymphocyte activation. Thus, this MLR-based in vivo model provides the opportunity to analyze positive regulators of T cell responses under physiological conditions of polyclonal T lymphocyte activation in vivo.

A Case of Autoimmune Hepatitis/Primary Biliary Cholangitis Overlap Syndrome during Treatment with Brodalumab for Generalized Pustular Psoriasis

Psoriasis is a chronic inflammatory skin disease characterized by accelerated tumor necrosis factor-α (TNF-α) /interleukin (IL) -23/IL-17 axis, epidermal hyperproliferation, and dysregulated differentiation. Psoriasis is occasionally associated with autoimmune liver diseases such as autoimmune hepatitis (AIH) or primary biliary cholangitis (PBC), caused by autoimmunity against hepatocyte- or cholangiocyte-specific autoantigens, respectively. Overlap syndrome is a condition in which patients have features of both AIH and PBC. It has been reported that AIH, PBC, or the overlap syndrome can be triggered by certain drug therapies. A 65-year-old Japanese man developed increased serum levels of aspartate and alanine aminotransferases, and positive anti-nuclear and anti-mitochondrial M2 antibodies, along with neutropenia, at 4 weeks of treatment with an anti-IL-17 receptor A antibody brodalumab for generalized pustular psoriasis. Histological evaluation of the liver revealed interface hepatitis and non-suppurative destructive cholangitis, which is compatible with the overlap syndrome of AIH and PBC. This is the first case of AIH/PBC overlap syndrome during treatment with brodalumab for generalized pustular psoriasis. The relationship between brodalumab and AIH/PBC overlap syndrome should be further elucidated. The risk of autoimmune liver diseases in patients with psoriasis treated with brodalumab should be carefully considered.

Cutaneous drug-induced lupus erythematosus: Clinical and immunological characteristics and update on new associated drugs

Cutaneous drug-induced lupus erythematosus (CDILE) is a lupus-like syndrome related to drug exposure which typically resolves after drug discontinuation. It can present as a systemic or a sole cutaneous form and different drugs may be associated with each form. CDILE pharmacoepidemiology is constantly changing. Indeed, older drugs primarily associated with systemic CDILE are no longer prescribed and new drugs associated with either cutaneous or systemic CDILE have emerged. The present study discusses the clinical and laboratory aspects of CDILE and the postulated pathogenesis, and it provides an update on implicated drugs. We performed a literature review to single out the new drugs associated with CDILE in the past decade (January 2010-June 2020). Among 109 drugs reported to induce CDILE in 472 patients, we identified anti-TNFα, proton-pump inhibitors, antineoplastic drugs, and, in particular, checkpoint inhibitors, as emerging drugs in CDILE. Most of the published studies are cases reports or small case series, and further larger studies as well as the development of validated classification criteria are needed to better understand and characterize their implication in CDILE.

Treatment-induced arteriolar revascularization and miR-126 enhancement in bone marrow niche protect leukemic stem cells in AML

BACKGROUND

During acute myeloid leukemia (AML) growth, the bone marrow (BM) niche acquires significant vascular changes that can be offset by therapeutic blast cytoreduction. The molecular mechanisms of this vascular plasticity remain to be fully elucidated. Herein, we report on the changes that occur in the vascular compartment of the FLT3-ITD+ AML BM niche pre and post treatment and their impact on leukemic stem cells (LSCs).

METHODS

BM vasculature was evaluated in FLT3-ITD+ AML models (MllPTD/WT/Flt3ITD/ITD mouse and patient-derived xenograft) by 3D confocal imaging of long bones, calvarium vascular permeability assays, and flow cytometry analysis. Cytokine levels were measured by Luminex assay and miR-126 levels evaluated by Q-RT-PCR and miRNA staining. Wild-type (wt) and MllPTD/WT/Flt3ITD/ITD mice with endothelial cell (EC) miR-126 knockout or overexpression served as controls. The impact of treatment-induced BM vascular changes on LSC activity was evaluated by secondary transplantation of BM cells after administration of tyrosine kinase inhibitors (TKIs) to MllPTD/WT/Flt3ITD/ITD mice with/without either EC miR-126 KO or co-treatment with tumor necrosis factor alpha (TNFα) or anti-miR-126 miRisten.

RESULTS

In the normal BM niche, CD31+Sca-1high ECs lining arterioles have miR-126 levels higher than CD31+Sca-1low ECs lining sinusoids. We noted that during FLT3-ITD+ AML growth, the BM niche lost arterioles and gained sinusoids. These changes were mediated by TNFα, a cytokine produced by AML blasts, which induced EC miR-126 downregulation and caused depletion of CD31+Sca-1high ECs and gain in CD31+Sca-1low ECs. Loss of miR-126high ECs led to a decreased EC miR-126 supply to LSCs, which then entered the cell cycle and promoted leukemia growth. Accordingly, antileukemic treatment with TKI decreased the BM blast-produced TNFα and increased miR-126high ECs and the EC miR-126 supply to LSCs. High miR-126 levels safeguarded LSCs, as shown by more severe disease in secondary transplanted mice. Conversely, EC miR-126 deprivation via genetic or pharmacological EC miR-126 knock-down prevented treatment-induced BM miR-126high EC expansion and in turn LSC protection.

CONCLUSIONS

Treatment-induced CD31+Sca-1high EC re-vascularization of the leukemic BM niche may represent a LSC extrinsic mechanism of treatment resistance that can be overcome with therapeutic EC miR-126 deprivation.

Neonatal Murine Model of Coxsackievirus A2 Infection for the Evaluation of Antiviral Therapeutics and Vaccination

Coxsackievirus (CV) A2 has emerged as an important etiological agent in the pathogen spectrum of hand, foot, and mouth disease (HFMD). The symptoms of CVA2 infections are generally mild, but worsen rapidly in some people, posing a serious threat to children's health. However, compared with enterovirus 71 detected frequently in fatal cases, limited attention has been paid to CVA2 infections because of its benign clinical course. In the present study, we identified three CVA2 strains from HFMD infections and used the cell-adapted CVA2 strain HN202009 to inoculate 5-day-old BALB/c mice intramuscularly. These mice developed remarkably neurological symptoms such as ataxia, hind-limb paralysis, and death. Histopathological determination showed neuronophagia, pulmonary hemorrhage, myofiberlysis and viral myocarditis. Viral replication was detected in multiple organs and tissues, and CVA2 exhibited strong tropism to muscle tissue. The severity of illness was associated with abnormally high levels of inflammatory cytokines, including interleukin (IL)-6, IL-10, tumor necrosis factor α, and monocyte chemotactic protein 1, although the blockade of these proinflammatory cytokines had no obvious protection. We also tested whether an experimental formaldehyde-inactivated CVA2 vaccine could induce protective immune response in adult mice. The CVA2 antisera from the vaccinated mice were effective against CVA2 infection. Moreover, the inactivated CVA2 vaccine could successfully generate immune protection in neonatal mice. Our results indicated that the neonatal mouse model could be a useful tool to study CVA2 infection and to develop CVA2 vaccines.

CD8 T cell-Derived Perforin and TNF-α Are Crucial Mediators of Neuronal Destruction in Experimental Autoimmune Enteric Ganglionitis

In neuron-specific ovalbumin-transgenic CKTAC mice, antigen-specific OT-I CD8 T cells home to the enteric nervous system, where they attack and destroy neurons of the myenteric and submucosal plexus. Clinically, experimental autoimmune enteric ganglionitis (EAEG) manifests with gastrointestinal dysmotility and rapidly progresses to lethal ileus. Although interferon-γ has been identified as capable of damaging neurons in EAEG, the role of perforin, Fas/FasL, and tumor necrosis factor-α (TNF-α) in this disease is still a matter of debate. Thus, CKTAC mice were adoptively transferred with either perforin^-/- or wild-type OT-I CD8 T cells. In addition, CKTAC mice that had received wild-type OT-I CD8 T cells were treated by either anti-TNF-α or anti-FasL. Furthermore, wild-type OT-I CD8 T cells were adoptively transferred into CKTAC mice with neuron-specific deletion of Fas. Although neither inactivation of enteric neuronal Fas nor anti-FasL treatment improved the disease, the absence of perforin from OT-I CD8 T cells and anti-TNF-α treatment significantly ameliorated EAEG and prevented lethal ileus by rescue of enteric neurons. Thus, these experiments identify perforin and TNF-α as important in the pathogenesis of EAEG.

Anti-tumor necrosis factor-induced lupus in patients with inflammatory bowel disease: a hospital-based cohort study from Korea

BACKGROUND

Anti-tumor necrosis factor (TNF) agents are increasingly used for rheumatic diseases and inflammatory bowel disease (IBD), but are associated with the development of anti-TNF-induced lupus (ATIL). Nonetheless, few ATIL studies on non-Caucasian IBD patients exist. Here, we investigated the incidence, clinical features, and risk factors of ATIL in Korea.

METHODS

We retrospectively reviewed the medical records of IBD patients undergoing anti-TNF therapy at our tertiary IBD center between 2008 and 2020. ATIL was diagnosed as a temporal association between symptoms and anti-TNF agents, and the presence of at least one serologic and non-serologic American College of Rheumatology criterion. The risk factors for ATIL occurrence were assessed using multivariate Cox regression analysis.

RESULTS

Of 1362 IBD patients treated with anti-TNF agents, 50 (3.7%) ATIL cases were suspected, of which 14 (1.0%) received a definitive diagnosis. Arthritis and mucocutaneous symptoms were observed in 13 and 4 patients, respectively. All ATIL cases were positive for anti-nuclear and anti-dsDNA antibodies. Four patients (30.8%) improved while continuing anti-TNF therapy. At the final follow up, the ATIL group (n = 14) had a lower IBD remission rate (30.8% versus 68.8%, p = 0.019) than the non-ATIL group (n = 36). Ulcerative colitis and longer disease duration were associated with ATIL occurrence, with hazard ratios of 7.017 (p = 0.005) and 1.118 (p = 0.002), respectively.

CONCLUSION

Although rare, ATIL is associated with poor treatment response to IBD in Korean patients. ATIL should be considered if arthritis and mucocutaneous symptoms develop during anti-TNF therapy for IBD.

The Effect of Biological Agents on Antinuclear Antibody Status in Patients with Psoriasis: A Single-Center Study

Background and Aims:

Biological agents are being used as treatment of psoriasis for years. However, autoimmunity can develop after the using of these agents. Antinuclear antibody (ANA) status changes during biological therapy can be affected by certain factors including the presence of immunosuppression. We aimed to evaluate the effect of antitumor necrosis factor agents and ustekinumab on ANA status, as well as other factors leading to change in ANA status such as history of phototherapy and methotrexate combination therapy.

Methods:

In this study, the laboratory findings of thirty-one patients with psoriasis who received biological agents including infliximab, etanercept, adalimumab, and ustekinumab from 2016 to 2018 managed at the department of dermatology were reviewed. The ANA status of the patients was evaluated every 2–3 months.

Results:

Twelve (38.7%) out of the thirty-one patients developed ANA positivity during treatment. Nine patients receiving infliximab, two patients receiving etanercept, and one patient receiving adalimumab developed ANA positivity. The nuclear homogeneous, nuclear fine speckled, and nuclear large/coarse speckled were the most common patterns of ANA. A patient receiving infliximab also developed anti-dsDNA positivity. None of the patients developed drug-induced lupus erythematosus or any autoimmune diseases. Concomitant methotrexate use and phototherapy history had no effect on ANA status statistically (P = 0.240 and 0.717, respectively).

Conclusion:

The emergence of ANA positivity during infliximab therapy among all biological agents was more common. ANA positivity during biologic agents does not cause any signs and symptoms of autoimmune diseases in patients with psoriasis; thus, it can be suggested that biological agents are not major risk factors for autoimmunity.

Adalimumab-associated Acquired Hemophilia in a Patient with Scleritis

Acquired hemophilia A (AHA) is a rare condition that may be drug-induced. In this case report, we describe a patient who presented with extensive subcutaneous bleeding three years after beginning treatment with adalimumab for necrotizing scleritis. His workup was compatible with drug-induced AHA. He was treated with high-dose corticosteroids, cyclophosphamide, and rituximab. Adalimumab was discontinued. We present this case as an example of a rare, but potentially life-threatening, complication of adalimumab.

Repository corticotropin injection attenuates collagen-induced arthritic joint structural damage and has enhanced effects in combination with etanercept

Background

Melanocortin receptor (MCR) agonists have anti-inflammatory and immunomodulatory properties mediated by receptors expressed on cells relevant to arthritis. Repository corticotropin injection (RCI; Acthar® Gel), an MCR agonist preparation, is approved as adjunctive therapy for rheumatoid arthritis (RA), but its mechanism of action in RA is unclear. This study explored the efficacy of RCI as monotherapy or adjunctive therapy with etanercept (ETN) in an established animal model of collagen-induced arthritis (CIA).

Methods

After induction of CIA, rats (n = 10 per group) were randomized to receive subcutaneous RCI (40, 160, or 400 U/kg twice daily) alone or in combination with ETN (10 mg/kg 3 times daily), ETN alone, or vehicle (on days 13 through 19). Inflammation was assessed via changes in paw edema. Bone damage was determined by microfocal computed tomography histopathology, and immunohistochemistry. Statistical analyses were performed using a 2-way analysis of variance (ANOVA) followed by the Newman-Keuls, Dunn’s, or Dunnett’s multiple comparisons test or a 1-way ANOVA followed by the Dunnett’s or Holm-Sidak multiple comparisons test.

Results

RCI administration resulted in dose-dependent decreases in ankle edema and histopathologic measures of inflammation, pannus formation, cartilage damage, bone resorption, and periosteal bone formation. RCI and ETN showed combined benefits on all parameters measured. Radiographic evidence of bone damage was significantly reduced in rats that received RCI alone or in combination with ETN. This reduction in bone density loss correlated with decreases in the number of CD68-positive macrophages and cathepsin K–positive osteoclasts within the lesions.

Conclusions

As monotherapy or adjunctive therapy with ETN, RCI attenuated CIA-induced joint structural damage in rats. These data support the clinical efficacy of RCI as adjunctive therapy for patients with RA.

Autoimmune blistering diseases provoked during the treatment of chronic inflammatory disease with biologic agents: a systematic review

BACKGROUND

To investigate the clinical course of autoimmune blistering diseases (AIBDs) following treatment with biologic agents (BAs) for chronic inflammatory diseases.

METHODS

A comprehensive review of available, published literature was performed using PubMed and CINAHL search engines. Diagnostic criteria of AIBD included positive direct immunofluorescence studies and/or positive serology with clinically suggestive features.

RESULTS

A total of 22 cases of AIBDs provoked by the use of BAs were found. The most commonly implicated agents were tumor necrosis factor-alpha inhibitors (n = 14). The mean age of onset of AIBD was 59.4 years (median 61.5 years, range 31-82). Average time to onset of AIBD following initiation of the suspected BA was 33.7 ± 43.8 weeks (range 3 days to 152 weeks). Psoriasis was the most common associated condition for which the BA was prescribed (n = 11), followed by rheumatoid arthritis (n = 6) and ulcerative colitis (n = 5). Of the 21 cases reporting AIBD outcome, 17 reported remission or complete resolution upon stopping treatment with the involved BA. Four cases reported continued bullae formation without worsening of disease following cessation of the BA or systemic corticosteroids used to treat the AIBD. Five cases rechallenged the patient with the involved BA and four of the five reported recurrence, often with quicker onset and more severe symptoms.

CONCLUSIONS

BAs may be suspected in patients developing AIBD while being treated for chronic inflammatory diseases. A majority of cases resolve upon cessation of the offending agent.

Cutaneous lupus erythematosus induced by drugs - novel insights

Introduction: There is a growing list of drugs implicated in inducing both subacute and chronic forms of cutaneous lupus erythematosus. It is important to recognize these drugs in order to quickly treat patients with drug induced disease.Areas covered: This paper reviews the current literature describing drugs implicated in causing cutaneous lupus erythematosus. A Pubmed search was used to compile a list of medications implicated up to August 2019. It reviews new classes of drugs identified as causing cutaneous lupus erythematosus, the pathophysiology of the disease process, and current recommendations for treatment of the disease.Expert opinion: Many drugs have been identified as inducing lupus, and many more continue to be described in new reports. Further research is needed to understand this phenomenon, which will aid in the diagnosis and treatment of affected patients.

Vitamin D alleviates acute graft-versus-host disease through promoting the generation of Foxp3+ T cells

Background

Acute graft-versus-host disease (aGVHD) is a medical complication which may result in significant morbidity and mortality after transplantation. The aim of this study investigated the therapeutic effect and underlying mechanism of 1,25-dihydroxyvitamin D3 (1α,25(OH)₂D₃) in the treatment of aGVHD.

Method

An aGVHD model was built by transferring splenocytes of B6 mice into B6D2F1 mice. 1α,25(OH)₂D₃ was added to evaluate the protective function to aGVHD; the phenotype and cytokine expression profile of spleen cells from the aGVHD model were determined using flow cytometry 2 weeks after the model is established.

Result

Administration of 1α,25(OH)₂D₃ significantly slowed aGVHD progression and improved survival of B6D2F1 recipients of grafted B6 splenocytes. 1α,25(OH)₂D₃ treatment also resulted in an increased number of CD4⁺Foxp3⁺ regulatory T cells (Tregs) but decreased the number of CD4⁺IL-4⁺ cells. In vitro analysis demonstrated that 1α,25(OH)₂D₃ directly increased forkhead box P3 (Foxp3) and IL-10 expression and enhanced the function of induced Tregs (iTregs).

Conclusions

This analysis indicated that the effect of 1α,25(OH)₂D₃ is mediated in part by improving the number of Tregs. 1α,25(OH)₂D₃ administration thus represents a viable approach for treating aGVHD.

In vivo IL-4 prevents allo-antigen driven CD8+ CTL development

IL-4 has been shown to suppress acute graft vs. host disease (GVHD) in irradiated hosts. Here we evaluated whether IL-4 suppresses acute GVHD in the un-irradiated parent-into-F1 GVHD model with relevance to renal allograft rejection. IL-4 completely suppressed CD8 CTL when administered with donor cells however this effect was lost if its administration was delayed 3days. IL-4 did not inhibit donor CD8⁺ T cell homing to the host spleen but rather prevented donor CD8⁺ T cell differentiation into CTLs. Studies with IL-4Rα-deficient donor cells or recipient mice demonstrated that IL-4 effects on the host, rather than, or in addition to IL-4 effects on donor cells, were critical for suppression of CTL. Because IL-4 decreased all splenic dendritic cell populations and increased neutrophil and CD8⁺ T cells, IL-4 may suppress donor CD8⁺ CTL by decreasing Ag presentation and/or increasing host myeloid and CD8⁺ T cell suppression of donor T cells.

Tumor Necrosis Factor and Lymphotoxin in Regulation of Intestinal Inflammation

Ulcerative colitis and Crohn's disease are the major forms of inflammatory bowel disease. Cytokines of the tumor necrosis factor (TNF) family play an important role in the regulation of intestinal inflammation. In this review, we discuss the function of key cytokines of this family - TNF and lymphotoxin (LT) - in mucosal healing, IgA production, and in control of innate lymphoid cells (ILCs), novel regulators of mucosal homeostasis in the gut. TNF plays a central role in the pathogenesis of inflammatory bowel diseases (IBD). LT regulates group 3 of ILCs and IL-22 production and protects the epithelium against damage by chemicals and mucosal bacterial pathogens. In addition, we discuss major mouse models employed to study the mechanism of intestinal inflammation, their advantages and limitations, as well as application of TNF blockers in the therapy for IBD.

Lessons for lupus from tumour necrosis factor blockade

Systemic lupus erythematosus (SLE) is a systemic non-organ specific autoimmune disease associated with multiple autoantibodies targeting autoantigens from the nucleus. Given the complex pathophysiology of SLE and the role of TNF alpha in that disease, modulation of TNF alpha (in SLE or non-SLE patients) using TNF blockers could either be detrimental or beneficial in some patients. In this review we will focus on lupus autoantibodies and clinical manifestations after TNF blockade in SLE patients and conversely on drug-induced-SLE in non-SLE patients. Some hypotheses regarding the mechanism of induction of autoantibodies in RA patients treated with TNF blockers are proposed.

Tumor necrosis factor alpha neutralization has no direct effect on parasite burden, but causes impaired IFN-γ production by spleen cells from human visceral leishmaniasis patients

The pro-inflammatory cytokine tumor necrosis factor (TNF)-α has an important role in control of experimental Leishmania donovani infection. Less is known about the role of TNF-α in human visceral leishmaniasis (VL). Evidence for a protective role is primarily based on case reports of VL development in individuals treated with TNF-α neutralizing antibody. In this study, we have evaluated how TNF-α neutralization affects parasite replication and cytokine production in ex vivo splenic aspirates (SA) from active VL patients. The effect of TNF-α neutralization on cell mediated antigen specific responses were also evaluated using whole blood cultures. Neutralization of TNF-α did not affect parasite numbers in SA cultures. Interferon (IFN)-γ levels were significantly reduced, but interleukin (IL)-10 levels were unchanged in these cultures. Leishmania antigen stimulated SA produced significant TNF-α which suggests that TNF-α is actively produced in VL spleen. Further it stimulates IFN-γ production, but no direct effect on parasite replication.

MPTP activates ASK1-p38 MAPK signaling pathway through TNF-dependent Trx1 oxidation in parkinsonism mouse model

Activation of apoptosis signal-regulating kinase 1 (ASK1)-p38 MAPK death signaling cascade is implicated in the death of dopaminergic neurons in substantia nigra in Parkinson's disease (PD). We investigated upstream activators of ASK1 using an MPTP mouse model of parkinsonism and assessed the temporal cascade of death signaling in ventral midbrain (VMB) and striatum (ST). MPTP selectively activated ASK1 and downstream p38 MAPK in a time-dependent manner in VMB alone. This occurred through selective protein thiol oxidation of the redox-sensitive thiol disulfide oxidoreductase, thioredoxin (Trx1), resulting in release of its inhibitory association with ASK1, while glutathione-S-transferase µ 1 (GSTM1) remained in reduced form in association with ASK1. Levels of tumor necrosis factor (TNF), a known activator of ASK1, increased early after MPTP in VMB. Protein covariation network analysis (PCNA) using protein states as nodes revealed TNF to be an important node regulating the ASK1 signaling cascade. In confirmation, blocking MPTP-mediated TNF signaling through intrathecal administration of TNF-neutralizing antibody prevented Trx1 oxidation and downstream ASK1-p38 MAPK activation. Averting an early increase in TNF, which leads to protein thiol oxidation resulting in activation of ASK1-p38 signaling, may be critical for neuroprotection in PD. Importantly, network analysis can help in understanding the cause/effect relationship within protein networks in complex disease states.

Adalimumab-Induced Cutaneous Lupus Erythematosus in a 16-Year-Old Girl with Juvenile Idiopathic Arthritis

Tumor necrosis factor α (TNF-α) antagonists are used in the treatment of numerous autoimmune conditions. Adalimumab is the first monoclonal antibody to TNF-α and is used to treat juvenile idiopathic arthritis. A growing body of literature associates anti-TNF-α therapies with several adverse dermatologic manifestations, including drug-induced lupus erythematosus (LE). We describe a case of cutaneous LE in a 16-year-old girl treated with adalimumab for juvenile idiopathic arthritis. The temporal association between her presenting symptoms and adalimumab initiation and gradual improvement after stopping biologic therapy suggest adalimumab-induced cutaneous LE. With increasing use of anti-TNF therapies in children, the potential for drug-induced LE should not be overlooked.

Adalimumab-induced lupus serositis

A 61-year-old man presented with a 1-month history of breathlessness, chest pain and lethargy. He had been taking adalimumab for ankylosing spondylitis for 2 years. Pleural and pericardial effusions were both found. A video-assisted thorascopic (VATS) pleural and lung biopsy were performed. The pleural pathology showed eosinophils, acute inflammatory cells and lymphoid aggregates. The patient was positive for antinuclear, antidouble-stranded and antihistone antibodies consistent with drug-induced lupus due to adalimumab. His serositis resolved on withdrawal of the drug. Drug-induced lupus can occur as a consequence of anti-TNF-α agents from induction of autoimmunity in a predisposed host.

The complex and central role of interferon-γ in graft-versus-host disease and graft-versus-tumor activity

Allogeneic hematopoietic cell transplantation (allo-HCT) is increasingly being performed to treat patients with hematologic malignancies. However, separating the beneficial graft-versus-tumor (GVT) or graft-versus-leukemia effects from graft-versus-host disease (GVHD) has been difficult and remains a significant challenge toward improving therapeutic efficacy and reducing toxicity of allo-HCT. GVHD is induced by donor T cells that also mediate potent anti-tumor responses. However, despite the largely shared effector mechanisms, extensive animal studies have demonstrated the potential of dissociating the GVT effect from GVHD. Also in many clinical cases, long-term remission was achieved following allo-HCT, without significant GVHD. A better mechanistic understanding of the immunopathophysiology of GVHD and GVT effects may potentially help to improve allo-HCT as well as maximize the benefit of GVT effects while minimizing GVHD. In this article, we review the role of IFN-γ in regulation of alloresponses following allo-HCT, with a focus on the mechanisms of how this cytokine may separate GVHD from GVT effects.

Antiphospholipid antibodies during 6-month treatment with infliximab: a preliminary report

BACKGROUND

The introduction of tumor necrosis factor (TNF) antagonists (adalimumab, infliximab, and etanercept) was a major advance and was highly important and beneficial in most rheumatoid arthritis (RA) patients. The adverse effects of this treatment are infrequent, but include opportunistic intracellular infection (especially the reactivation of latent Mycobacterium tuberculosis); exacerbation of demyelinating disorders; and the production of various types of antibodies such as antinuclear antibodies (ANA) or double-stranded DNA autoantibodies (dsDNA) and antiphospholipid antibodies (aPL) such as anti-cardiolipin antibodies (aCL) and anti-B2GP-I antibodies (B2GP-I). The aim of the study was to determine the prevalence of aCL and B2GP-I in IgM and IgG classes, using ELISA tests, during 6 months of follow-up in patients with refractory RA successfully treated with infliximab.

MATERIAL/METHODS

We determined the prevalence of aCL and B2GP-I in IgM and IgG classes, using ELISA tests, during 6 months of follow-up in patients with refractory RA successfully treated with infliximab.

RESULTS

We observed a statistically important increase only in the group of B2GP-I IgM (p<0.05). There are contradictory results concerning the ability of infliximab to induce aPL, but most authors confirm this phenomenon.

CONCLUSIONS

Further investigations are needed to determine if the new aPL appears in patients with β2-GPI gene polymorphisms such as leucine-to-valine substitution at position 247, which can lead to a conformational changes in β2-GPI protein, leading to aPL synthesis. The role of aPL in pathogenesis of APS is still unclear, but we should remember the immunogenic aspect of TNF antagonist treatment. Therefore, we recommend early detection of aPL and observation of the patient, paying special attention to signs and symptoms of thromboembolism.

Immune-mediated inflammatory reactions and tumors as skin side effects of inflammatory bowel disease therapy

All drugs currently used for treating patients with inflammatory bowel disease (IBD - including Crohn's disease and ulcerative colitis) have the potential to induce skin lesions ranging from mild eruptions to more serious and widespread clinical presentations. The number of cutaneous adverse reactions due to IBD therapies is progressively increasing and the most frequently involved drugs are thiopurines and biologics like tumor necrosis factor (TNF)-α antagonists. The main drug-induced cutaneous manifestations are non-melanoma skin cancer (NMSC), notably basal cell and squamous cell carcinomas, and viral skin infections for thiopurines and psoriasiform, eczematoid and lichenoid eruptions as well as skin infections and cutaneous lupus erythematosus for biologics. Cutaneous manifestations should be promptly recognized and correctly diagnosed in order to quickly establish an adequate therapy. The main treatment for NMSC is surgical excision whereas the management of immune-mediated inflammatory skin reactions varies from topical therapy for mild presentations to the shift to another drug alone or in combination with corticosteroids for extensive eruptions.

Unexpected hematologic effects of biotherapeutics in nonclinical species and in humans

Biotherapeutics are expanding the arsenal of therapeutics available for treating and preventing disease. Although initially thought to have limited side effects due to the specificity of their binding, these drugs have now been shown to have potential for adverse drug reactions including effects on peripheral blood cell counts or function. Hematotoxicity caused by a biotherapeutic can be directly related to the activity of the biotherapeutic or can be indirect and due to autoimmunity, biological cascades, antidrug antibodies, or other immune system responses. Biotherapeutics can cause hematotoxicity primarily as a result of cellular activation, cytotoxicity, drug-dependent and independent immune responses, and sequelae from initiating cytokine and complement cascades.  The underlying pathogenesis of biotherapeutic-induced hematotoxicity often is poorly understood. Nonclinical studies have generally predicted clinical hematotoxicity for recombinant cytokines and growth factors.  However, most hematologic liabilities of biotherapeutics are not based on drug class but are species specific, immune-mediated, and of low incidence. Despite the potential for unexpected hematologic toxicity, the risk-benefit profile of most biotherapeutics is favorable; hematologic effects are readily monitorable and managed by dose modification, drug withdrawal, and/or therapeutic intervention.  This article reviews examples of biotherapeutics that have unexpected hematotoxicity in nonclinical or clinical studies. 

Dermatological adverse reactions during anti-TNF treatments: focus on inflammatory bowel disease

The clinical introduction of tumour necrosis factor (TNF) inhibitors has deeply changed the treatment of inflammatory bowel diseases (IBD). It has demonstrated impressive efficacy as compared to alternative treatments, allowing for the chance to achieve near-remission and long-term improvement in function and quality of life and to alter the natural history of Crohn's disease (CD) and ulcerative colitis (UC). As a consequence of longer follow-up periods the number of side effects which may be attributed to treatment with biologics is growing significantly. Cutaneous reactions are among the most common adverse reactions. These complications include injection site reactions, cutaneous infections, immune-mediated complications such as psoriasis and lupus-like syndrome and rarely skin cancers. We review the recent literature and draw attention to dermatological side effects of anti-TNF therapy of inflammatory bowel disease.

Anti-tumor necrosis factor-α induced systemic lupus erythematosus in a patient with metastatic Crohn's disease--what is the role of anti-TNF antibody?

Biological therapies are supposed to trigger the development of autoimmune diseases. We report a case of a 27-year old woman presenting with drug induced systemic lupus erythematosus (SLE) associated with infliximab therapy. The development of paradoxical inflammation in immune-mediated inflammatory diseases patients treated with anti TNF-α suggests that an unknown inflammatory pathway may be provoked by inhibiting TNF-α. We suppose that in our case a cross reactivity between anti-infliximab antibodies and autoantibodies may lead to the development of TNF-induced immune disease.

In vivo maturation of allo-specific CD8 CTL and prevention of lupus-like graft-versus-host disease is critically dependent on T cell signaling through the TNF p75 receptor but not the TNF p55 receptor

A third signal is required for maturation of effector CD8 CTL in addition to TCR and CD28 engagement. Inflammatory cytokines can provide a third signal; however, in nonpathogen settings (i.e., antitumor responses), the identity of the third signal is not clear. A useful model for in vivo CD8 CTL in the absence of exogenous pathogens is the alloantigen-driven parent-into F1 model of acute graft-versus-host disease (GVHD) characterized by a strong TNF-dependent donor antihost CD8 CTL T cell response. To determine whether TNF acts directly on donor T cells in a signal 3 manner, F1 mice received TNFR 1 (p55) knockout (KO) and/or TNFR 2 (p75) KO donor T cells. Donor p75 KO but not p55KO donor T cells failed to induce acute GVHD phenotype and instead induced a lupus-like chronic GVHD both short and long term because of quantitative and qualitative donor T cell defects, that is, reduced perforin, IFN-γ, and TNF production. Transfer of mixed or matched purified CD4 and CD8 T cells from wild type or p75KO donors demonstrated that optimal CTL maturation required p75 signaling in both CD4 and CD8 T cells. Despite defective p75KO CD4 help for CD8 CTL, p75KO CD4 help for B cells and autoimmunity was intact. These results provide a mechanism by which impaired CD8 CTL could contribute to reduced antiviral and antitumor responses and autoimmunity reported in patients receiving TNF blockers. Our results support the idea that selective p55 blockade may be beneficial by reducing inflammation without compromising CD8 CTL.

Anti-tumor necrosis factor α treatment of interferon-α-induced murine lupus nephritis reduces the renal macrophage response but does not alter glomerular immune complex formation

OBJECTIVE

To analyze the mechanism for the therapeutic effects of tumor necrosis factor α (TNFα) inhibition in a murine model of systemic lupus erythematosus.

METHODS

We used the (NZB × NZW)F(1) (NZB/NZW) mouse model of interferon-α-induced lupus nephritis and treated mice with TNF receptor type II (TNFRII) Ig after TNFα expression was detected in the kidneys. Autoantibodies were measured by enzyme-linked immunosorbent assay (ELISA), and autoantibody- forming cells were determined using an enzyme-linked immunospot assay. Activation of splenocytes was analyzed by flow cytometry. Kidneys were harvested and analyzed using flow cytometry, immunohistochemistry, ELISA, Western blotting, and real-time polymerase chain reaction.

RESULTS

TNFRII Ig treatment stabilized nephritis and markedly prolonged survival. Autoantibody production and systemic immune activation were not inhibited, but the renal response to glomerular immune complex deposition was attenuated. This was associated with decreases in renal production of chemokines, renal endothelial cell activation, interstitial F4/80(high) macrophage accumulation, tubular damage, and oxidative stress. In contrast, perivascular lymphoid aggregates containing B cells, T cells, and dendritic cells accumulated unabated.

CONCLUSION

Our data suggest that TNFα is a critical cytokine that amplifies the response of the nephron to immune complex deposition, but that it has less influence on the response of the systemic vasculature to inflammation.

Broad range of adverse cutaneous eruptions in patients on TNF-alpha antagonists

Biologic therapies targeting tumor necrosis factor (TNF)-alpha have become a mainstay in the management of a number of autoimmune diseases. We report a series of adverse skin eruptions in six patients (four females, two males, age: 21-58 years, mean: 39) receiving 4 months to 10 years (mean 3.1 years) of anti-TNF-alpha therapies (infliximab, n = 4; adalimumab, n = 1 or etanercept, n = 1). The following drug-associated diagnoses were made in eight skin biopsies performed at Massachusetts General Hospital between 3/2007 and 10/2010: pustular folliculitis, psoriasis, interface dermatitis, neutrophilic eccrine hidradenitis, Sweet's syndrome, lupus, vasculitis and palmoplantar pustulosis. The descriptions of neutrophilic eccrine hidradenitis-like and Sweet's-like hypersensitivity eruptions induced by anti-TNF-alpha therapies are the first such cases described in the literature. Each cutaneous eruption improved or resolved with switching to a different TNF-alpha inhibitor, discontinuation of the anti-TNF-alpha agent, and/or topical or systemic steroids. There was a clear chronologic relationship with, and clinical remission upon withdrawal or steroid suppression of the anti-TNF-alpha agents. The mechanism for such diverse cutaneous eruptions among this class of medications remains poorly understood. The cutaneous adverse reaction profile of TNF-alpha inhibitors is broad and should be considered in the histopathologic differential in this clinical setting.

Pleiotropic targets: the problem of shared signaling circuitry in rheumatoid arthritis disease progression and protection

The immune response is replete with feedback control at many levels. These protective circuits are even functional within the arthritic joint, tempering disease to varying extents. An optimal therapy would inhibit autoimmune processes while maintaining protective circuitry. However, many of the cells and proteins that serve as important mediators of disease progression also play an active role in these protective circuits. The hypothesis considered in this review is that the inadvertent inhibition of protective circuitry adversely affects efficacy. Conversely, if therapeutics can be designed, which avoid inhibiting known regulatory circuits, efficacy will be improved. Understanding where these processes share signaling molecules will be crucial to the development of the next generation of therapeutics. This review discusses three well-defined signal transduction cascades; IL-2, IFNγ and TNF-α, and demonstrate within two cell types, T cells and macrophages, how these cytokines may contribute both to protection and to disease progression.

Onset of lupus like syndrome in patients with spondyloarthritis treated with anti-TNF-α

Background

The anti-TNFα therapy has been since its approval by the FDA, along with nonsteroidal antiinflammatory drugs (NSAIDs), one of the most important therapies for control of spondyloarthritis (SpA). The onset of Lupus Like Syndrome (LLS) has been described in patients with rheumatoid arthritis (RA) treated with anti-TNFα therapy but there is little literature on the occurrence of this entity in patients with SpA.

Methods

We studied 57 patients with SpA who received more than 1 year of anti-TNFα therapy (infliximab, adalimumab or etanercept). Patients were analyzed for the development of LLS, in addition to measuring ANA levels ≥ 1:160 and Anti-dsDNA (measured by IIF).

Results

In total, 7.01% of patients treated with anti-TNFα had titers of ANA ≥ 1:160, whereas 3.5% of patients had serum levels of dsDNA. However, only one patient (1.75%; n = 1) experienced clinical symptoms of LLS; this was a female patient with a history of psoriatic arthritis.

Conclusions

The presence of LLS secondary to anti-TNFα therapy in patients with SpA is observed less frequently compared with patients with RA. LLS was only detected in a patient with a history of psoriasis since youth, who developed psoriatic arthritis after 27 years of age and had received anti-TNFα therapy for > 2 years. This may be because LLS is an entity clearly associated with innate immunity, with little central role of B and T cells.

The parent-into-F1 murine model in the study of lupus-like autoimmunity and CD8 cytotoxic T lymphocyte function

The transfer of homozygous C57Bl/6 (B6) or DBA/2 (DBA) parental strain T cells into normal B6D2F1 mice in the parent-into-F1 (p → F1) model results in a graft-vs.-host disease (GVHD) that takes one of the following two forms: (a) acute GVHD seen with B6 → F1 mice and mediated by donor CD8 cytotoxic T cells that eliminate host lymphocytes and (b) a chronic lupus-like GVHD seen with DBA → F1 mice and mediated by donor CD4 T cell cognate help to autoreactive B cells resulting in autoantibody production and renal disease similar to human lupus. Importantly, these two phenotypes can be distinguished by flow cytometry as early as 2 weeks after donor cell transfer. The p → F1 model can be used to screen for agents that alter lupus development. Additionally, the model is useful for preclinical screening of biologic agents with immunomodulatory potential. Agents that selectively inhibit CD8 T cell function will convert acute GVHD to chronic GVHD in B6 → F1 mice. Conversely, agents that promote CD8 CTL function will convert chronic GVHD to acute GVHD in DBA → F1 mice. Agents that completely suppress T cell function will block both phenotypes. The model is also useful for examining the effects of T cell mutations by transferring mutant T cells into wild-type hosts and assessing the effects on disease phenotype. Differences observed from wild-type T cells → F1 can be directly ascribed to alterations in mutant T cell function. Because of the early 2-week phenotype development, the p → F1 model is well suited to screening of potential immunomodulatory therapeutic compounds and the assessment of T cell mutations on in vivo function.