Localization of sclerotic-type chronic graft-vs-host disease to sites of skin injury: potential insight into the mechanism of isomorphic and isotopic responses

Chronic graft-versus-host disease. Part I: Epidemiology, pathogenesis, and clinical manifestations

Chronic graft-versus-host disease is a major complication of allogeneic hematopoietic cell transplantation and a leading cause of long-term morbidity, nonrelapse mortality, and impaired health-related quality of life. The skin is commonly affected and presents heterogeneously, making the role of dermatologists critical in both diagnosis and treatment. In addition, new clinical classification and grading schemes inform treatment algorithms, which now include 3 U.S. Food and Drug Administration-approved therapies, and evolving transplant techniques are changing disease epidemiology. Part I reviews the epidemiology, pathogenesis, clinical manifestations, and diagnosis of chronic graft-versus-host disease. Part II discusses disease grading and therapeutic management.

Understanding and treatment of cutaneous graft-versus-host-disease

The skin is the outermost mechanical barrier where dynamic immune reactions take place and is the most commonly affected site in both acute and chronic graft-versus-host disease (GVHD). If not properly treated, pain and pruritis resulting from cutaneous GVHD can increase the risk of secondary infection due to erosions, ulcerations, and damage of underlying tissues. Furthermore, resulting disfiguration can cause distress and significantly impact patients' quality of life. Thus, a deeper understanding of skin-specific findings of GVHD is needed. This review will highlight some promising results of recent pre-clinical studies on the pathophysiology of skin GVHD and summarize the diagnostic and staging/grading procedures according to the clinical manifestations of skin GVHD. In addition, we will summarize outcomes of various GVHD treatments, including skin-specific response rates.

PD-L1's Role in Preventing Alloreactive T Cell Responses Following Hematopoietic and Organ Transplant

Over the past decade, Programmed Death-Ligand 1 (PD-L1) has emerged as a prominent target for cancer immunotherapies. However, its potential as an immunosuppressive therapy has been limited. In this review, we present the immunological basis of graft rejection and graft-versus-host disease (GVHD), followed by a summary of biologically relevant molecular interactions of both PD-L1 and Programmed Cell Death Protein 1 (PD-1). Finally, we present a translational perspective on how PD-L1 can interrupt alloreactive-driven processes to increase immune tolerance. Unlike most current therapies that block PD-L1 and/or its interaction with PD-1, this review focuses on how upregulation or reversed sequestration of this ligand may reduce autoimmunity, ameliorate GVHD, and enhance graft survival following organ transplant.

A critical review of belumosudil in adult and pediatric patients with chronic graft-versus-host disease

INTRODUCTION

Chronic graft-versus-host disease (cGVHD) is a complication of allogeneic hematopoietic cell transplantation (allo-HCT) and is the main cause of late non-relapse mortality (NRM). Three new agents are now approved to treat cGVHD, of which belumosudil has a unique and dual mechanism of action of i) targeting the Rho-GTPase-associated coiled-coil kinase 2 (ROCK2) in T helper follicular cells (TFH) and TH17 cells, this results in downregulation of proinflammatory cytokines (interleukin -21 and 17), the former in a STAT3-dependent mechanism, ii) inhibition of tissue fibrosis by targeting stress-induced polymerization of G-actin fibrils by inhibiting the Rho-ROCK-MRTF pathway.

AREAS COVERED

In this review we describe the epidemiology of cGVHD, its cardinal symptoms, preventive and therapeutic options, including second-line approved therapies in the United States (US). Clinical trial data that led to approval of belumosudil is discussed, in addition to the clinical scenarios in which the approved drugs may be most applicable.

EXPERT OPINION

Belumosudil is approved for treatment of adult and pediatric patients ≥ 12 years with cGVHD after failing two lines of therapy based on results of the ROCKstar study that showed high overall response rates (ORR), favorable adverse effect profiles, and low rates of severe infections. With the availability of three new agents for treatment of cGVHD, treating physicians have more therapeutic options for patients and have additional options of development new clinical trials using a combination of recently approved drugs.

Wolf's Isotopic Response After Herpes Zoster Infection in Chronic Lichen Sclerosus-Like Graft versus Host Disease: Case Report and Literature Review

Wolf's isotopic response (WIR) refers to the occurrence of a new skin disease at the exact site of an unrelated skin disease that had previously healed, often subsequent to virus infection. Secondary cutaneous diseases that are frequently observed in WIR include granulomatous reactions, dysimmune reactions, malignancies, and infections. However, secondary chronic graft-versus-host disease (GVHD) is rare. We describe a patient with lichen sclerosus-like GVHD who developed lichen planus-like GVHD lesions secondary to herpes zoster infection.

Insights into mechanisms of graft-versus-host disease through humanised mouse models

Graft-versus-host disease (GVHD) is a major complication that occurs following allogeneic haematopoietic stem cell transplantation (HSCT) for the treatment of haematological cancers and other blood-related disorders. GVHD is an inflammatory disorder, where the transplanted donor immune cells can mediate an immune response against the recipient and attack host tissues. Despite over 60 years of research, broad-range immune suppression is still used to prevent or treat GVHD, leading to an increased risk of cancer relapse and infection. Therefore, further insights into the disease mechanisms and development of predictive and prognostic biomarkers are key to improving outcomes and reducing GVHD development following allogeneic HSCT. An important preclinical tool to examine the pathophysiology of GVHD and to understand the key mechanisms that lead to GVHD development are preclinical humanised mouse models. Such models of GVHD are now well-established and can provide valuable insights into disease development. This review will focus on models where human peripheral blood mononuclear cells are injected into immune-deficient non-obese diabetic (NOD)-scid-interleukin-2(IL-2)Rγ mutant (NOD-scid-IL2Rγ^null) mice. Humanised mouse models of GVHD can mimic the clinical setting for GVHD development, with disease progression and tissues impacted like that observed in humans. This review will highlight key findings from preclinical humanised mouse models regarding the role of donor human immune cells, the function of cytokines and cell signalling molecules and their impact on specific target tissues and GVHD development. Further, specific therapeutic strategies tested in these preclinical models reveal key molecular pathways important in reducing the burden of GVHD following allogeneic HSCT.

SGK1, a Critical Regulator of Immune Modulation and Fibrosis and a Potential Therapeutic Target in Chronic Graft-Versus-Host Disease

Patients with severe chronic graft-versus-host disease (cGVHD) always experience debilitating tissue injury and have poorer quality of life and shorter survival time. The early stage of cGVHD is characterized by inflammation, which eventually leads to extensive tissue fibrosis in various organs, such as skin and lung, eventually inducing scleroderma-like changes and bronchiolitis obliterans syndrome. Here we review the functions of serum/glucocorticoid regulated kinase 1 (SGK1), a hub molecule in multiple signal transduction pathways and cell phosphorylation cascades, which has important roles in cell proliferation and ion channel regulation, and its relevance in cGVHD. SGK1 phosphorylates the ubiquitin ligase, NEDD4, and induces Th cells to differentiate into Th17 and Th2 phenotypes, hinders Treg development, and promotes inflammatory fibrosis. Phosphorylation of NEDD4 by SGK1 also leads to up-regulation of the transcription factor SMAD2/3, thereby amplifying the fibrosis-promoting effect of TGF-β. SGK1 also up-regulates the inflammatory transcription factor, nuclear factor-κB (NF-κB), which in turn stimulates the expression of multiple inflammatory mediators, including connective tissue growth factor. Overexpression of SGK1 has been observed in various fibrotic diseases, including pulmonary fibrosis, diabetic renal fibrosis, liver cirrhosis, hypertensive cardiac fibrosis, peritoneal fibrosis, and Crohn’s disease. In addition, SGK1 inhibitors can attenuate, or even reverse, the effect of fibrosis, and may be used to treat inflammatory conditions and/or fibrotic diseases, such as cGVHD, in the future.

Biomarkers for acute and chronic graft versus host disease: state of the art

INTRODUCTION

Despite significant advances in treatment and prevention, graft-versus-host disease (GVHD) still represents the main cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Thus, considerable research efforts have been made to find and validate reliable biomarkers for diagnosis, prognosis, and risk stratification of GVHD.

AREAS COVERED

In this review the most recent evidences on different types of biomarkers studied for GVHD, such as genetic, plasmatic, cellular markers, and those associated with microbiome, were summarized. A comprehensive search of peer-review literature was performed in PubMed including meta-analysis, preclinical and clinical trials, using the terms: cellular and plasma biomarkers, graft-versus-host disease, cytokines, and allogeneic hematopoietic stem cell transplantation.

EXPERT OPINION

In the near future, several validated biomarkers will be available to help clinicians in the diagnosis of GVHD, the identification of patients at high risk of GVHD development and in patients' stratification according to its severity. Then, immunosuppressive treatment could be tailored to each patient's real needs. However, more efforts are needed to achieve this goal. Although most of the proposed biomarkers currently lack validation with large-scale clinical data, their study led to improved knowledge of the biological basis of GVHD, and ultimately to implementation of GHVD treatment.

Allogeneic donor split skin grafts for treatment of refractory ulcers in cutaneous chronic graft-versus-host disease after allogeneic hematopoietic stem cell transplantation-a retrospective analysis on seven patients

Refractory skin ulcers due to severe chronic graft-versus-host disease (cGVHD) remain to be associated with significant morbidity and mortality.We performed an allogeneic donor skin transplantation in seven adult patients after allogeneic hematopoietic stem cell transplantation for cGVHD-associated refractory skin ulcers. While four patients received a split skin graft (SSG), in one patient, a full thickness skin graft for two small refractory ulcers of the ankle was performed, and one patient received in vitro expanded donor keratinocyte grafts derived from hair roots of the original unrelated donor. In one additional patient, a large deep fascial defect of the lower leg was covered with an autologous greater omentum free graft before coverage with an allogeneic SSG. An additional patient was treated with an autologous scrotal skin graft for a refractory ulcer associated with deep sclerosis of cGVHD after unrelated donor transplantation.All skin grafts engrafted and resulted in permanent coverage of the grafted ulcers without any signs of immunological mediated damage. In the patient receiving in vitro expanded keratinocyte grafts, two localized ulcers were permanently covered by donor skin while this approach failed to cover extensive circular ulcers of the lower legs.Allogeneic donor skin grafts are a valuable treatment option in refractory ulcers due to cGVHD but are restricted mainly to related donors while keratinocyte grafts from unrelated donors remain experimental. In male patients lacking a related donor, autologous scrotal skin graft may be an alternative option.

The Anatomic Distribution of Skin Involvement in Patients with Incident Chronic Graft-versus-Host Disease

Little is known about the anatomic distribution of cutaneous chronic graft-versus-host disease (cGVHD). Using data from the cGVHD Consortium Improving Outcomes Assessment Study, we describe the frequency and extent of erythema and superficial and deep sclerosis in 8 anatomic sites in patients with incident disease (ie, new cGVHD diagnosis within 3 months of study entry) receiving systemic therapy. Of 339 patients with incident disease, 182 (54%) had skin involvement. When an extremity was involved, the same type of disease was present contralaterally in 92% of cases, revealing a high level of symmetry. As anticipated, erythema was the most common incident feature; however, sclerotic skin involvement at the time of cGVHD diagnosis was more common than has been suggested by previous studies. Erythema occurred in 155 (85%) and sclerosis in 53 (29%) of the patients with skin involvement (46% and 16%, respectively, of the entire cohort of 339 incident cGVHD cases). Erythema was least common on the lower extremities (n = 71; 39% of patients with skin involvement). Moveable sclerosis was rare on the head, neck, and scalp (n = 4; 2%). Deep sclerosis did not occur in this region, and instead was most likely to occur on the upper extremities (n = 14; 8%) and lower extremities (n = 14; 8%). More than one-half of patients with erythema (n = 107; 58.7%) had diffuse involvement (4 or more of 8 sites involved), compared with less than one-third of those with sclerosis (n = 16; 30.2%).

The Biology of Chronic Graft-versus-Host Disease: A Task Force Report from the National Institutes of Health Consensus Development Project on Criteria for Clinical Trials in Chronic Graft-versus-Host Disease

Chronic graft-versus-host disease (GVHD) is the leading cause of late, nonrelapse mortality and disability in allogeneic hematopoietic cell transplantation recipients and a major obstacle to improving outcomes. The biology of chronic GVHD remains enigmatic, but understanding the underpinnings of the immunologic mechanisms responsible for the initiation and progression of disease is fundamental to developing effective prevention and treatment strategies. The goals of this task force review are as follows: This document is intended as a review of our understanding of chronic GVHD biology and therapies resulting from preclinical studies, and as a platform for developing innovative clinical strategies to prevent and treat chronic GVHD.

Upregulation of IFN-Inducible and Damage-Response Pathways in Chronic Graft-versus-Host Disease

Although chronic graft-versus-host disease (CGVHD) is the primary nonrelapse complication of allogeneic transplantation, understanding of its pathogenesis is limited. To identify the main operant pathways across the spectrum of CGVHD, we analyzed gene expression in circulating monocytes, chosen as in situ systemic reporter cells. Microarrays identified two interrelated pathways: 1) IFN-inducible genes, and 2) innate receptors for cellular damage. Corroborating these with multiplex RNA quantitation, we found that multiple IFN-inducible genes (affecting lymphocyte trafficking, differentiation, and Ag presentation) were concurrently upregulated in CGVHD monocytes compared with normal subjects and non-CGVHD control patients. IFN-inducible chemokines were elevated in both lichenoid and sclerotic CGHVD plasma and were linked to CXCR3+ lymphocyte trafficking. Furthermore, the levels of the IFN-inducible genes CXCL10 and TNFSF13B (BAFF) were correlated at both the gene and the plasma levels, implicating IFN induction as a factor in elevated BAFF levels in CGVHD. In the second pathway, damage-/pathogen-associated molecular pattern receptor genes capable of inducing type I IFN were upregulated. Type I IFN-inducible MxA was expressed in proportion to CGVHD activity in skin, mucosa, and glands, and expression of TLR7 and DDX58 receptor genes correlated with upregulation of type I IFN-inducible genes in monocytes. Finally, in serial analyses after transplant, IFN-inducible and damage-response genes were upregulated in monocytes at CGVHD onset and declined upon therapy and resolution in both lichenoid and sclerotic CGVHD patients. This interlocking analysis of IFN-inducible genes, plasma analytes, and tissue immunohistochemistry strongly supports a unifying hypothesis of induction of IFN by innate response to cellular damage as a mechanism for initiation and persistence of CGVHD.

Chronic cutaneous lichenoid graft-versus-host disease at the area of herpes zoster infection and at a vaccination site

Cutaneous graft-versus-host disease (GVHD) is a frequent complication of allogeneic bone marrow transplant and haematopoietic cell transplantation, but it is rarely presented as a Wolf's isotopic response. We report a patient who developed chronic lichenoid GVHD following the dermatomes previously affected by varicella zoster virus (VZV) infection. Nineteen months later, the same patient suffered from reactivation of GVHD at the injection site of an influenza vaccination. We review the literature concerning GVHD appearing after VZV infection and discuss the possible implications of this case and the pathogenic hypotheses.

The immunocompromised district in dermatology: A unifying pathogenic view of the regional immune dysregulation

Besides the systemic immune deficiency, a sectorial default in immune control may occur in immunocompetent subjects. This regional immune defect can appear and remain confined to differently damaged skin areas, lately labeled immunocompromised districts (ICDs). An ICD is a skin area more vulnerable than the rest of the body for genetic or acquired reasons. Its vulnerability mainly consists in a local dysregulation of the immune control, which often facilitates (but sometimes hinders) the local onset of immunity-related eruptions or skin disorders. The factors responsible for localized immune dysregulation are multifarious, being represented by chronic lymphatic stasis, herpetic infections, ionizing or ultraviolet (UV) radiations, burns, all sorts of trauma (especially amputation), tattooing, intradermal vaccinations, and others of disparate nature (eg, paralytic stroke, poliomyelitis). Whatever the cause, in time an ICD may become a vulnerable site, prone to developing opportunistic infections, tumors, or dysimmune reactions (often of granulomatous type), strictly confined to the district itself; however, the opposite may also occur with systemic immune disorders or malignancies that selectively spare the district. In any case, the immunologic behavior of an ICD is different from that of the rest of the body. The pathomechanisms involved in this sectorial immune destabilization may reside in locally hampered lymph drainage that hinders the normal trafficking of immunocompetent cells (eg, chronic lymphedema, posttraumatic lymph stasis) or in a damage to sensory nerve fibers that release immunity-related peptides (eg, herpetic infections, carpal tunnel syndrome), or in both conditions (eg, amputation stump, radiation dermatitis). The ICD is a conceptual entity with no definite shape or dimension. It may take an extremely variable form and extent depending on the causative agent, ranging from a minimal area (eg, intradermal vaccination) or a small area (eg, herpes simplex infection), through a wide area (eg, radiotherapy), a bandlike segment (eg, skin mosaicism, herpes zoster infection), or an acral area (eg, carpal tunnel syndrome), up to a whole limb (eg, Stewart-Treves syndrome) or even an entire half body (eg, brain stroke). Varied newly coined terminology can be used to indicate the specific cause each time that it is responsible for a regional immune dysregulation. The advantage of the umbrella term ICD is that it encompasses all the possible causes involved in a local immune destabilization. An ICD may have a congenital or a postnatal origin, and interesting similarities between the two forms exist. An ICD may also take place in patients with a preexisting systemic immune deficiency, thus creating a more vulnerable site in an already vulnerable patient. Identifying a cutaneous ICD in a given patient is an important standpoint for both diagnostic and prevention purposes. This can be proven by the educative clinical examples that are reported here.

The role of skin trauma in the distribution of morphea lesions: a cross-sectional survey of the Morphea in Adults and Children cohort IV

BACKGROUND

Skin trauma may play a role in the development of morphea lesions. The association between trauma and the distribution of cutaneous lesions has never been examined to our knowledge.

OBJECTIVE

We sought to determine whether patients enrolled in the Morphea in Adults and Children (MAC) cohort exhibit skin lesions distributed in areas of prior (isotopic) or ongoing (isomorphic) trauma.

METHODS

This was a cross-sectional analysis of the MAC cohort.

RESULTS

Of 329 patients in the MAC cohort, 52 (16%) had trauma-associated lesions at the onset of disease. Patients with lesions in an isotopic distribution had greater clinical severity as measured by a clinical outcome measure (mean modified Rodnan Skin Score of 13.8 vs 5.3, P = .004, 95% confidence interval 3.08-13.92) and impact on life quality (mean Dermatology Life Quality Index score 8.4 vs 4.1, P = .009, 95% confidence interval 1.18-7.50) than those with an isomorphic distribution. Most frequent associated traumas were chronic friction (isomorphic) and surgery/isotopic.

LIMITATIONS

Recall bias for patient-reported events is a limitation.

CONCLUSION

Of patients in the MAC cohort, 16% developed initial morphea lesions at sites of skin trauma. If these findings can be confirmed in additional series, they suggest that elective procedures and excessive skin trauma or friction might be avoided in these patients.

Radiation port cutaneous metastases: reports of two patients whose recurrent visceral cancers presented as skin lesions at the site of previous radiation and literature review

Radiation therapy is associated with a variety of complications, including the development of primary skin cancers in the radiated region. However, it is rare for patients with visceral cancers who are treated with radiation therapy to subsequently develop cutaneous metastasis within the radiation port. We describe two patients with internal malignancies who developed cutaneous metastases within their radiation ports following radiotherapy. In addition, we used PubMed to perform an extensive literature review and identify additional reports of cutaneous metastasis within a radiation port. We excluded patients who developed melanoma or primary skin cancers in the radiation port. We also excluded patients with non-solid organ malignancies. Herein, we summarize the characteristics of 23 additional patients who experienced radiation port cutaneous metastases and explore possible mechanisms for the occurrence of radiation port cutaneous metastases.

Isomorphic sclerotic-type cutaneous chronic graft-versus-host disease: report and review of chronic graft-versus-host disease in a cutaneous immunocompromised district

Background

Patients who have received a hematopoietic cell transplantation can develop graft-versus-host disease (GVHD). The liver, the gastrointestinal tract, and/or the skin can be affected by GVHD. Chronic sclerotic-type cutaneous GVHD can occur at sites of repetitive skin friction.

Purpose

To describe isomorphic sclerotic-type GVHD and review chronic GVHD appearing in a cutaneous immunocompromised district.

Methods

The clinical features of a 74-year-old man with mantle cell lymphoma who developed chronic sclerotic-type cutaneous GVHD localized to the waistband area—which had been exposed to repetitive skin injury—after a second hematopoietic cell transplantation are reported. Using the PubMed database, an extensive literature search was performed on chronic GVHD.

Case report and review

The cutaneous immunocompromised district is an area of skin whose local effective immunity has been altered, thereby permitting the development of a dysimmune reaction, infection, or tumor at the site. A cutaneous isomorphic response refers to a disease-associated skin lesion occurring at the site of physical injury that is morphologically similar to the existing condition. Cutaneous chronic GVHD can occur at sites of repetitive skin trauma as an isomorphic response. The patient developed sclerotic-type GVHD in a cutaneous area that had previously experienced repeated irritation, friction, and pressure. Isomorphic sclerotic-type GVHD—in either the waistband area or brassiere area or both—has also been observed in other patients. In addition, cutaneous chronic GVHD has been described not only at the location of a previous, unrelated, and healed skin disease as an isotopic response, but also at the cutaneous site of earlier exposure to radiotherapy or ultraviolet radiation as an isoradiotopic response.

Conclusion

Sclerotic and nonsclerotic skin lesions of chronic GVHD can occur not only as an isomorphic response, but also as either an isotopic response or an isoradiotopic response in a cutaneous immunocompromised district.

Graft-versus-host disease: part I. Pathogenesis and clinical manifestations of graft-versus-host disease

Approximately 25,000 allogeneic hematopoietic cell transplants are performed worldwide each year for a variety of malignant and non-malignant conditions. Graft-versus-host disease represents one of the most frequent complications and is a major source of long-term morbidity and mortality. Whereas acute graft-versus-host disease is induced by recognition of host tissues as foreign by immunocompetent donor cells, the pathogenesis of chronic graft-versus-host disease is not as well understood, and continues to be a major treatment challenge. Part I of this two-part series reviews the epidemiologic factors, classification, pathogenesis, and clinical manifestations of acute and chronic graft-versus-host disease. Part II discusses the topical, physical, and systemic treatment options available to patients with graft-versus-host disease.

Sclerotic-type chronic GVHD of the skin: clinical risk factors, laboratory markers, and burden of disease

Chronic GVHD is one of the most severe complications of allogeneic HSCT. The sclerotic skin manifestations of cGVHD (ScGVHD) result from inflammation and fibrosis of the dermis, subcutaneous tissue, or fascia, leading to significant functional disability. Risk factors and clinical markers associated with ScGVHD remain largely unexamined. By using a single-visit, cross-sectional design, we evaluated 206 patients with cGVHD at the National Institutes of Health. Most patients manifested severe (ie, 63% National Institutes of Health score "severe"), refractory disease (median treatments = 4). ScGVHD was detected in 109 (52.9%) patients. ScGVHD was associated with greater platelet count (P < .001) and C3 (P < .001), and decreased forced vital capacity (P = .013). Total body irradiation (TBI) was associated with development of ScGVHD (P = .002). TBI administered in reduced-intensity conditioning was most strongly associated with ScGVHD (14/15 patients, P < .0001). Patients with ScGVHD had significant impairments of joint range of motion and grip strength (P < .001). Greater body surface area involvement was associated with poorer survival (P = .015). We conclude that TBI, particularly in reduced-intensity regimens, may be an important risk factor for ScGVHD. Widespread skin involvement is associated with significant functional impairment, distressing symptoms, and diminished survival. This trial is registered at http://www.clinicaltrials.gov as NCT00331968.