Extracorporeal photopheresis as graft-versus-host disease prophylaxis: a randomized controlled trial: Prophylactic extracorporeal photopheresis to prevent graft-versus-host disease

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative option for many patients diagnosed with hematological malignancies. A major obstacle is graft-versus-host disease (GvHD) causing significant morbidity and mortality. Extracorporeal photopheresis (ECP) is an increasingly applied GvHD treatment, partly due to its favourable safety profile. In contrast, the use of ECP in preventing GvHD is sparse, and randomized controlled trials (RCTs) are lacking.

OBJECTIVE

We therefore conducted a RCT to assess if ECP applied post-transplant, could prevent the development of GvHD within the first year of transplantation.

STUDY DESIGN

We enrolled 157 patients (18-74 years) with a hematological malignancy receiving first allo-HSCT: 76 randomized to the intervention group and 81 to the control group. ECP was initiated directly upon engraftment and was planned twice weekly for two weeks, then once weekly for four weeks. GvHD, relapse, and death were analyzed with Cox regression analysis.

RESULTS

During the first year, 45 patients in the intervention and 52 control patients developed GvHD (HR=0.82, 95% CI 0.55-1.22, P=0.32). There were no differences in acute or chronic GvHD or its organ distribution in this intention-to-treat RCT. A per-protocol analysis revealed a significant difference in GvHD between the intervention (per-protocol; n=39 of 76) and the control group (n=77), 46% vs 68%, respectively, (HR 0.47, 95% CI 0.27-0.80, P=0.006). Relapse occurred in 15 patients in the intervention group and in 11 patients among the controls (HR=1.38, 95% CI 0.64-3.01, P=0.42). GvHD-free relapse-free (GRFS) survival, event-free survival, overall survival and non-relapse mortality did not differ significantly between the two study groups. No significant difference in immune reconstitution between the two study groups was revealed.

CONCLUSION

This first intention-to-treat RCT, investigating ECP as GvHD prophylaxis in allo-HSCT for hematological malignancy does not support the use of ECP as adjunct to standard drug-based GvHD-prophylaxis. This trial was registered at www.

CLINICALTRIALS

gov as #NCT03204721.

Thymectomy in Juvenile Myasthenia Gravis Is Safe Regarding Long Term Immunological Effects

Thymectomy is an established treatment in adult MG and also recommended for the treatment of post-pubertal onset juvenile MG. Whether the youngest children should be thymectomized is still debated. Signs of premature aging of the immune system have been shown in studies on early perioperative thymectomy in children with congenital heart defect. In this retrospective cohort study the objective was to investigate the long-term effects of treatment related thymectomy on T cell subsets and T cell receptor rearrangement excision circles (TRECs) in peripheral blood of juvenile myasthenia gravis (MG) patients, as well as clinical occurrence of autoimmune disorders, malignancies and infectious diseases. Forty-seven patients with onset of myasthenia gravis before the age of 19 years were included; 32 (68.1%) had been thymectomized and 15 (31.8%) had not. They were studied at varying times after thymectomy (7–26 years). We found a significant lower number of naïve helper T cells (CD4+CD45RA+) with an increased proportion of memory helper T cells (CD4+CD45RO+), and a significant lower number of naïve cytotoxic T cells (CD8+CD27+CD28+) in the thymectomized patients. In addition they showed a significant reduction in the number of TRECs and proportion of recent thymic emigrants (RTE) compared to non-thymectomized patients. In none of them an increased frequency of malignancies or infections was found. Our findings indicate a premature aging of the immune system after thymectomy in juvenile MG, but associated clinical consequences could not be verified.

Second-Tier Next Generation Sequencing Integrated in Nationwide Newborn Screening Provides Rapid Molecular Diagnostics of Severe Combined Immunodeficiency

Severe combined immunodeficiency (SCID) and other T cell lymphopenias can be detected during newborn screening (NBS) by measuring T cell receptor excision circles (TRECs) in dried blood spot (DBS) DNA. Second tier next generation sequencing (NGS) with an amplicon based targeted gene panel using the same DBS DNA was introduced as part of our prospective pilot research project in 2015. With written parental consent, 21 000 newborns were TREC-tested in the pilot. Three newborns were identified with SCID, and disease-causing variants in IL2RG, RAG2, and RMRP were confirmed by NGS on the initial DBS DNA. The molecular findings directed follow-up and therapy: the IL2RG-SCID underwent early hematopoietic stem cell transplantation (HSCT) without any complications; the leaky RAG2-SCID received prophylactic antibiotics, antifungals, and immunoglobulin infusions, and underwent HSCT at 1 year of age. The child with RMRP-SCID had complete Hirschsprung disease and died at 1 month of age. Since January 2018, all newborns in Norway have been offered NBS for SCID using 1st tier TRECs and 2nd tier gene panel NGS on DBS DNA. During the first 20 months of nationwide SCID screening an additional 88 000 newborns were TREC tested, and four new SCID cases were identified. Disease-causing variants in DCLRE1C, JAK3, NBN, and IL2RG were molecularly confirmed on day 8, 15, 8 and 6, respectively after birth, using the initial NBS blood spot. Targeted gene panel NGS integrated into the NBS algorithm rapidly delineated the specific molecular diagnoses and provided information useful for management, targeted therapy and follow-up i.e., X rays and CT scans were avoided in the radiosensitive SCID. Second tier targeted NGS on the same DBS DNA as the TREC test provided instant confirmation or exclusion of SCID, and made it possible to use a less stringent TREC cut-off value. This allowed for the detection of leaky SCIDs, and simultaneously reduced the number of control samples, recalls and false positives. Mothers were instructed to stop breastfeeding until maternal cytomegalovirus (CMV) status was determined. Our limited data suggest that shorter time-interval from birth to intervention, may prevent breast milk transmitted CMV infection in classical SCID.

Altered gut microbiota profile in common variable immunodeficiency associates with levels of lipopolysaccharide and markers of systemic immune activation

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency characterized by low immunoglobulin (Ig)G and IgA, and/or IgM. In addition to bacterial infections, a large subgroup has noninfectious inflammatory and autoimmune complications. We performed 16S ribosomal RNA-based profiling of stool samples in 44 CVID patients, 45 patients with inflammatory bowel disease (disease controls), and 263 healthy controls. We measured plasma lipopolysaccharide (LPS) and markers of immune cell activation (i.e., soluble (s) CD14 and sCD25) in an expanded cohort of 104 patients with CVID and in 30 healthy controls. We found a large shift in the microbiota of CVID patients characterized by a reduced within-individual bacterial diversity (alpha diversity, P<0.001) without obvious associations to antibiotics use. Plasma levels of both LPS (P=0.001) and sCD25 (P<0.0001) were elevated in CVID, correlating negatively with alpha diversity and positively with a dysbiosis index calculated from the taxonomic profile. Low alpha diversity and high dysbiosis index, LPS, and immune markers were most pronounced in the subgroup with inflammatory and autoimmune complications. Low level of IgA was associated with decreased alpha diversity, but not independently from sCD25 and LPS. Our findings suggest a link between immunodeficiency, systemic immune activation, LPS, and altered gut microbiota.

A potential founder variant in CARMIL2/RLTPR in three Norwegian families with warts, molluscum contagiosum, and T-cell dysfunction

Background

Four patients from three Norwegian families presented with a common skin phenotype of warts, molluscum contagiosum, and dermatitis since early childhood, and various other immunological features. Warts are a common manifestation of human papilloma virus (HPV), but when they are overwhelming, disseminated and/or persistent, and presenting together with other immunological features, a primary immunodeficiency disease (PIDD) may be suspected.

Methods and results

The four patients were exome sequenced as part of a larger study for detecting genetic causes of primary immunodeficiencies. No disease‐causing variants were identified in known primary immunodeficiency genes or in other disease‐related OMIM genes. However, the same homozygous missense variant in CARMIL2 (also known as RLTPR) was identified in all four patients. In each family, the variant was located within a narrow region of homozygosity, representing a potential region of autozygosity. CARMIL2 is a protein of undetermined function. A role in T‐cell activation has been suggested and the mouse protein homolog (Rltpr) is essential for costimulation of T‐cell activation via CD28, and for the development of regulatory T cells. Immunophenotyping demonstrated reduced regulatory, CD4+ memory, and CD4+ follicular T cells in all four patients. In addition, they all seem to have a deficiency in IFNγ ‐synthesis in CD4+ T cells and NK cells.

Conclusions

We report a novel primary immunodeficiency, and a differential molecular diagnosis to CXCR4‐,DOCK8‐,GATA2‐,MAGT1‐,MCM4‐,STK4‐,RHOH‐,TMC6‐, and TMC8‐related diseases. The specific variant may represent a Norwegian founder variant segregating on a population‐specific haplotype.

Retinoic acid improves defective TLR9/RP105-induced immune responses in common variable immunodeficiency-derived B cells

Common variable immunodeficiency (CVID) is a disease that is characterized primarily by low levels of serum Igs, resulting in a high incidence of infections. It also has been associated with impaired B cell signaling via TLR9 and reduced serum levels of vitamin A. Given the established link between vitamin A deficiency and increased susceptibility to infections, we investigated the ability of the vitamin A metabolite all-trans retinoic acid (RA) to restore the defective immune responses in CVID-derived B cells activated through the TLRs TLR9 and RP105. We demonstrate that RA almost normalizes proliferation and IL-10 secretion in patient-derived B cells. IgG secretion is also partially restored, but to a more moderate extent. This can be explained by impaired RA-mediated isotype switching in TLR9/RP105-stimulated CVID-derived B cells owing to reduced induction of activation-induced deaminase. Accordingly, these B cells secreted higher levels of IgM than did normal B cells, and RA augmented IgM secretion. The ability of RA to improve critical immune parameters in CVID-derived B cells stimulated through TLR9 and RP105 support the possibility of combining RA with TLR stimulation for the treatment of CVID.

Altered Th17 cells and Th17/regulatory T-cell ratios indicate the subsequent conversion from undifferentiated connective tissue disease to definitive systemic autoimmune disorders

A shift in the balance between Th17-cells and regulatory T-cells (Treg) is an important feature of systemic autoimmune diseases (SAID), and may also contribute to their development. Hereby, we assessed the distribution of peripheral Th17 and Treg-cells in patients with undifferentiated connective tissue disease (UCTD), the forerunner of SAIDs and followed these parameters during the development towards definitive SAIDs. Fifty-one UCTD patients were investigated and followed-up for 3 years. Flow cytometry was used to identify and follow three cell-populations: Th17-cells (CD4+IL-17+ T-cells), natural regulatory T-cells (CD4(+)CD25(bright)FoxP3(+); nTregs) and IL-10 producing Type-1 regulatory T-cells (CD4+IL-10+ T-cells; Tr1). Altogether 37.3% of these patients progressed into SAIDs. Th17-cells were increased in UCTD vs. controls, which further increased in those, whom developed SAIDs eventually. The Th17/nTreg ratio gradually increased from controls through UCTD patients, reaching the highest values in SAID-progressed patients. Regarding the Th17/Tr1 ratios, a similar tendency was observed moreover Th17/Tr1 could distinguish between UCTD patients with, or without subsequent SAID progression in a very early UCTD stage. Various immunoserological markers showed association with Th17 and Th17/nTreg at baseline, indicating the consecutive development of a distinct SAID. The derailed Th17/Treg balance may contribute to disease progression therefore could function as a prognostic marker.

Assessment of intracellular cytokines and regulatory cells in patients with autoimmune diseases and primary immunodeficiencies - novel tool for diagnostics and patient follow-up

Serum and intracytoplasmic cytokines are mandatory in host defense against microbes, but also play a pivotal role in the pathogenesis of autoimmune diseases by initiating and perpetuating various cellular and humoral autoimmune processes. The intricate interplay and fine balance of pro- and anti-inflammatory processes drive, whether inflammation and eventually organ damage will occur, or the inflammatory cascade quenches. In the early and late, as well as inactive and active stages of autoimmune diseases, different cellular and molecular patterns can dominate in these patients. However, the simultaneous assessment of pro- and anti-inflammatory biomarkers aids to define the immunological state of a patient. A group of the most useful inflammatory biomarkers are cytokines, and with increasing knowledge during the last decade their role have been well-defined in patients with autoimmune diseases and immunodeficiencies. Multiple pathological processes drive the development of autoimmunity and immunodeficiencies, most of which involve quantitative and qualitative disturbances in regulatory cells, cytokine synthesis and signaling pathways. The assessment of these biomarkers does not aid only in the mechanistic description of autoimmune diseases and immunodeficiencies, but further helps to subcategorize diseases and to evaluate therapy responses. Here, we provide an overview, how monitoring of cytokines and regulatory cells aid in the diagnosis and follow-up of patients with autoimmune diseases and immunodeficiencies furthermore, we pinpoint novel cellular and molecular diagnostic possibilities in these diseases.

Aspirin potentiates LPS-induced fibrin formation (FPA) and TNF-alpha-synthesis in whole blood

The effect of aspirin on LPS-incubation of whole blood was investigated. Aspirin induced a concentration dependent increase (2.5-5-fold at 5 mM aspirin) in LPS-induced appearance of TNF-alpha and fibrinopeptide A (FPA) in plasma, despite the concomitant increase in the inhibitory cytokine IL-100. Aspirin substantially raised the levels of LPS-induced TF-mRNA and TNFalpha-mRNA in monocytes isolated from whole blood. The median ratio for TF-/beta-actin mRNA increased from 1.5 +/- 0.44 in the presence of LPS-alone, to 2.5 +/- 0.51 when 5 mM aspirin was added. The TNFalpha/beta-actin mRNA ratios were 1.8 +/- 0.4 and 5.5 +/- 2.7 respectively. Addition of exogenous PGE2 before incubation nearly abrogated the effect of aspirin on TNF-alpha, substantiating the role of PGE2 as a regulator of TNF-alpha synthesis, whereas the effect on FPA was small. Thus, in the presence of LPS in this whole blood model, aspirin apparently had a pro-inflammatory rather than an anti-inflammatory effect.

Acetylsalicylic acid and sodium salicylate inhibit LPS-induced NF-kappa B/c-Rel nuclear translocation, and synthesis of tissue factor (TF) and tumor necrosis factor alfa (TNF-alpha) in human monocytes

We have investigated the effects of acetylsalicylic acid and sodium salicylate on the LPS-induced synthesis of the pro-coagulant protein tissue factor (TF) and the pro-inflammatory protein tumor necrosis factor-alpha (TNF-alpha), as well as the prostaglandin PGE2 in human monocytes. Both drugs dose-dependently inhibited LPS-induced TF and TNF-alpha synthesis at the mRNA and the protein level, and reduced PGE2 production. As evidenced by electro mobility shift assay (EMSA) and the use of a NF-kappa B prototypic probe, these drugs probably exert their inhibitory effects by interference with the nuclear translocation of NF-kappa B/c-Rel proteins. These data may expand the understanding of the anti-thrombotic and anti-inflammatory effects of these drugs when activation of monocytes occurs.

Inhibition of IL-1 induced tissue factor (TF) synthesis and procoagulant activity (PCA) in purified human monocytes by IL-4, IL-10 and IL-13

Exposure of monocytes to pro-inflammatory cytokines or lipopolysaccharide (LPS) may induce synthesis and expression of tissue factor (TF). In this paper we have focused on the induction of TF-activity in human monocytes by the pro-inflammatory cytokines recombinant human interleukin 1 (rhIL-1 alpha) (rhIL-1 beta) (rhIL-6) and human tumour necrosis factor alpha (rhTNF-alpha), measured as procoagulant activity (PCA) in a microtitre plate-based clot assay. In addition we have studied the modulation of IL-1 alpha/beta induced TF-mRNA and PCA by rhIL-4, rhIL-10 and rhIL13. IL-1 alpha and IL-1 beta induced a concentration dependent increase in TF-activity. Neither IL-6 nor TNF-alpha gave rise to procoagulant activity at the concentrations tested (0.2-20 ng/ml). IL-4, IL-10 and IL-13, all effectively diminished IL-1 alpha/beta induced PCA, shown at the protein- and at the mRNA-level, while cell viability was unaffected. These results add to the previously demonstrated role of IL-4 and IL-10 as inhibitors of LPS-induced TF-activity, showing that these anti-inflammatory cytokines are not specific for LPS-activation but interfere with other stimulating substances such as IL-1, which may be involved in diseases where LPS is not present.

Procoagulant and profibrinolytic activities of cryopreserved human monocytes

The purpose of this study was to compare the ability of fresh and cryopreserved mononuclear cells to generate thrombin, induce fibrin formation and finally resolve the fibrin formed, when exposed to plasma. Peripheral blood mononuclear cells (PBM) from 4 donors were collected by gradient centrifugation on Lymfoprep, and cryopreserved in fetal calf serum and 10% dimethyl sulfoxide. Viability was tested by exclusion of trypan blue, as well as green/red fluorescence of fluorescein-diacetate and ethidium bromide (FDA/EB). Fresh and frozen-thawed cells were seeded, stimulated with lipopolysaccharide(LPS), and exposed to a standard heparinized overlay plasma. Plasma was harvested at intervals (0-7 days). Thrombin generation and fibrin formation were measured by quantification of prothrombin fragment (F1 + 2) and fibrinopeptide A (FPA) and the fibrinolytic capacity of the cells as the amount of fibrin (ogen) degradation products (FbDP and FgDP). Recovery of cells after thawing was about 80%, and the viability of fresh and cryopreserved PBM was > 95%. Compared to fresh, frozen cells fully retained their capability of Tissue Factor synthesis, leading to prothombinase activity (F1 + 2) and fibrin formation (FPA). In contrast, the fibrinolytic capacity of frozen-thawed cells were significantly reduced. As expected there were significant variations between the donors in all the parameters measured. We conclude that cryopreservation of human blood mononuclear cells is possible with maintainance of the potential of the cells to mediate coagulation in plasma upon LPS stimulation, whereas the fibrin resolving capacity apparently is reduced by the preservation procedure.