The PID Odyssey 2030: outlooks, unmet needs, hurdles, and opportunities - proceedings from the IPOPI global multi-stakeholders' summit (June 2022).

IPOPI held its first Global Multi-Stakeholders' Summit on 23-24 June 2022 in Cascais, Portugal. This IPOPI initiative was designed to set the stage for a stimulating forward-thinking meeting and brainstorming discussion among stakeholders on the future priorities of the PID community. All participants were actively engaged in the entire Summit, bringing provocative questions to ensure a high level of discussion and engagement, and partnered in identifying the outlooks, unmet needs, hurdles and opportunities of PIDs for 2030. The topics that were covered include diagnosis (e.g., newborn screening [NBS], genomic sequencing- including ethical aspects on the application of genomics on NBS, the role of more accurate and timely diagnostics in impacting personalized management), treatment (e.g., the therapeutic evolution of immunoglobulins in a global environment, new therapies such as targeted therapies, new approaches in curative therapies), the interactions of Primary ID with Secondary ID, Autoinflammatory Diseases and other diseases as the field experiences an incessant evolution, and also the avenues for research in the field of humanities and human sciences such as Patient-Reported Outcome Measures (PROMs), Patient-Reported Experience Measures (PREMs), and Health-Related Quality Of Life (HRQoL). During this meeting, all participants contributed to the drafting of recommendations based on our common understanding of the future opportunities, challenges, and scenarios. As a collection of materials, perspectives and summaries, they are succinct and impactful and may help determine some of the next key steps for the PID community.

Tissue IgG2/IgG4 Ratio as an Additional Tool to Distinguish IgG4-Related Disease From Other Fibroinflammatory Disorders.

Interpretation of biopsies taken on suspicion of immunoglobulin (Ig)G4-related disease (IgG4-RD) may be hampered by uninterpretable immunohistochemical stains for IgG because of strong background signals. This study aims to determine the significance of tissue IgG2 positive plasma cell counts in IgG4-RD in comparison with non-IgG4-related inflammatory disorders. Descriptive, retrospective case-control study of 16 patients with IgG4-related orbital disease (IgG4-ROD) and 24 with extraorbital IgG4-RD. Histopathology and serology of this group was compared with 16 patients with orbital non-IgG4-related disorders and 22 patients with extraorbital non-IgG4-related disorders. The mean tissue IgG2/IgG4 ratio was 0.16 in IgG4-ROD and 0.27 in extraorbital IgG4-RD and far below 1 in 98% of patients. This was significantly lower compared with the non-IgG4-related disorders that showed a mean tissue IgG2/IgG4 ratio of 1.98 in the orbital and 2.20 in the extraorbital group (range: 0.20 to 10, P <0.05). In 74% of tissue samples an IgG2/IgG4 ratio >1 was seen. The tissue IgG2/IgG ratio was significantly lower in IgG4-RD compared with non-IgG4-related inflammatory disorders. Serum IgG2 concentration was not abnormal in patients with IgG4-RD. A significantly lower tissue IgG2/IgG4 and IgG2/IgG ratio was observed in IgG4-RD, compared with non-IgG4-related inflammatory disorders. Additional immunohistochemical staining for IgG2 positive plasma cells can be helpful in the diagnosis of IgG4-RD. Especially in cases with uninterpretable IgG staining, a well-recognized problem that may give rise to a failed interpretation of the biopsy.

Leukocyte toll-like receptor expression in pathergy positive and negative Behçet's disease patients.

OBJECTIVES: To investigate whether the auto-inflammatory nature and the pathergic reaction in Behçet's disease (BD) are driven by a disturbed toll-like receptor (TLR) response. METHODS: We compared both TLR expression by flow-cytometry and TLR response by stimulation assay in 18 BD patients (both pathergy positive and pathergy negative) with 15 healthy controls. RESULTS: Expression of TLR1 and 2 was significantly elevated in B-lymphocytes of BD patients compared with healthy controls. TLR1, 2 and 4 were significantly more highly expressed in both CD4+ and CD8+ T-lymphocytes of BD patients. Granulocytes of BD patients displayed significantly higher expression of TLR1, 2, 4 and 6. TLR2, 4 and 5 expression was significantly increased on classical monocytes of BD patients. Intermediate monocytes of BD patients showed an increase in expression of TLR2. Furthermore, TLR2 and 5 were significantly more highly expressed in non-classical monocytes of BD patients. In pathergy positive patients, TLR5 was even more highly expressed compared with pathergy negative patients on B- and T-lymphocytes and granulocytes. Furthermore, TLR2 and 5 showed an elevated TNF-α response to stimulation with their cognate ligands. CONCLUSION: Immune cells of BD patients overexpress TLR1, 2, 4, 5 and 6. Furthermore, after stimulation of TLR2 and 5, BD patients demonstrate a more potent TNF-α response. Although this is a small cohort, in the pathergy positive patients, TLR5 expression is even further augmented, suggesting that a microbial (flagellin) or damage (HMGB1) associated signal may trigger the exaggerated immune response that is characteristic for the pathergy phenomenon in BD. In conclusion, these results point to an exaggerated TLR response in the auto-inflammatory nature of BD.

IgG4-Related Disease of Skull Base: Case Series of 3 Patients with Headache.

BACKGROUND: IgG4-related disease (IgG4-RD) is an immune-mediated, systemic, fibroinflammatory disease. IgG4-RD may manifest in almost every part of the human body. Here, we describe 3 patients with a skull base manifestation of IgG4-RD that mimicked malignancy. CASE DESCRIPTION: Patient 1, a 73-year-old male, presented with a mass in the left nasopharynx and clivus. Patient 2, a 73-year-old male, presented with a mass in the left petrous bone and clivus with involvement of the left jaw joint. Patient 3, a 50-year-old male, presented with a lytic lesion of the clivus and sphenoid bone. All patients complained of headache and hearing loss. Serum IgG4 was normal, and imaging did not show systemic manifestation. Histology established the diagnosis of IgG4-RD. Two patients were treated successfully with prednisolone, hydroxychloroquine, and radiotherapy. One patient is monitored without treatment. CONCLUSIONS: The described cases emphasize the broad clinical spectrum of IgG4-RD. The diagnostic workup may be challenging, and serum IgG4 may be normal, as demonstrated in these cases. Careful histopathologic examination of the tissues remains essential. Timely diagnosis of IgG4-RD is important to prevent secondary organ damage in patients with active disease.

Hyper-IgE in the allergy clinic--when is it primary immunodeficiency?

The 2017 International Union of Immunological Societies (IUIS) classification recognizes 3 hyper-IgE syndromes (HIES), including the prototypic Job's syndrome (autosomal dominant STAT3-loss of function) and autosomal recessive PGM3 and SPINK5 syndromes. Early diagnosis of PID can direct life-saving or transformational interventions; however, it remains challenging owing to the rarity of these conditions. This can result in diagnostic delay and worsen prognosis. Within increasing access to "clinical-exome" testing, clinicians need to be aware of the implication and rationale for genetic testing, including the benefits and limitations of current therapies. Extreme elevation of serum IgE has been associated with a growing number of PID syndromes including the novel CARD11 and ZNF341 deficiencies. Variable elevations in IgE are associated with defects in innate, humoral, cellular and combined immunodeficiency syndromes. Barrier compromise can closely phenocopy these conditions. The aim of this article was to update readers on recent developments at this important interface between allergy and immunodeficiency, highlighting key clinical scenarios which should draw attention to possible immunodeficiency associated with extreme elevation of IgE, and outline initial laboratory assessment and management.

Genetic defects in PI3Kδ affect B-cell differentiation and maturation leading to hypogammaglobulineamia and recurrent infections.

BACKGROUND: Mutations in PIK3CD and PIK3R1 cause activated PI3K-δ syndrome (APDS) by dysregulation of the PI3K-AKT pathway. METHODS: We studied precursor and peripheral B-cell differentiation and apoptosis via flowcytometry. Furthermore, we performed AKT-phosphorylation assays and somatic hypermutations (SHM) and class switch recombination (CSR) analysis. RESULTS: We identified 13 patients of whom 3 had new mutations in PIK3CD or PIK3R1. Patients had low total B-cell numbers with increased frequencies of transitional B cells and plasmablasts, while the precursor B-cell compartment in bone marrow was relatively normal. Basal AKT phosphorylation was increased in lymphocytes from APDS patients and natural effector B cells where most affected. PI3K mutations resulted in altered SHM and CSR and increased apoptosis. CONCLUSIONS: The B-cell compartment in APDS patients is affected by the mutations in PI3K. There is reduced differentiation beyond the transitional stage, increased AKT phosphorylation and increased apoptosis. This B-cell phenotype contributes to the clinical phenotype.

IgG4-related disease: a systematic review of this unrecognized disease in pediatrics.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a systemic fibro-inflammatory condition with an unclear pathophysiological mechanism affecting different parts of the body. If untreated, the disease can lead to fibrosis and irreversible organ damage. IgG4-RD mostly has been described in adults, hence it is generally unknown among pediatricians. This systematic search of the literature provides an overview of all reports published on IgG4-RD in children in order to create awareness of IgG4-RD in pediatrics and to emphasize the broad clinical presentation of this disease. METHODS: A systematic literature search of Embase, Medline, Web-of-Science, PubMed publisher, Cochrane and Google Scholar was performed for case reports on IgG4-RD in children. RESULTS: Of total 740 articles identified by the search, 22 case reports including 25 cases of IgG4-RD in children were found. The median age of the children was 13 years, of which 64 % were girls. IgG4-related orbital disease (44 %) and autoimmune pancreatitis type 1/IgG4-related pancreatitis (12 %) predominantly occurred. Less frequently, other manifestations as pulmonary manifestation, cholangitis and lymphadenopathy were also found. Almost all cases were histologically proven. Prednisone was the first choice of treatment leading to favorable clinical response in 83 % of the cases. Maintenance therapy with steroid sparing agents was required in 43 % of the cases needing therapy. Rituximab was successful in all 4 cases, whereas, the disease modifying rheumatic drugs (DMARDs) mycophenolate mofetil, azathioprine and methotrexate were effective in almost 50 % of the cases. CONCLUSION: IgG4-RD in children is a generally unknown disease among pediatricians, but several pediatric cases have been described. Prednisone is the first choice of treatment leading to disease remission in the majority of the cases. DMARDs and rituximab are alternative effective steroid sparing agents with more positive evidence for the latter.

Strategies for B-cell receptor repertoire analysis in primary immunodeficiencies: from severe combined immunodeficiency to common variable immunodeficiency.

The antigen receptor repertoires of B- and T-cells form the basis of the adaptive immune response. The repertoires should be sufficiently diverse to recognize all possible pathogens. However, careful selection is needed to prevent responses to self or harmless antigens. Limited antigen receptor repertoire diversity leads to immunodeficiency, whereas unselected or misdirected repertoires can result in autoimmunity. The antigen receptor repertoire harbors information about abnormalities in many immunological disorders. Recent developments in next generation sequencing allow the analysis of the antigen receptor repertoire in much greater detail than ever before. Analyzing the antigen receptor repertoire in patients with mutations in genes responsible for the generation of the antigen receptor repertoire will give new insights into repertoire formation and selection. In this perspective, we describe strategies and considerations for analysis of the naive and antigen-selected B-cell repertoires in primary immunodeficiency patients with a focus on severe combined immunodeficiency and common variable immunodeficiency.

Somatostatin analogues for receptor targeted photodynamic therapy.

Photodynamic therapy (PDT) is an established treatment modality, used mainly for anticancer therapy that relies on the interaction of photosensitizer, light and oxygen. For the treatment of pathologies in certain anatomical sites, improved targeting of the photosensitizer is necessary to prevent damage to healthy tissue. We report on a novel dual approach of targeted PDT (vascular and cellular targeting) utilizing the expression of neuropeptide somatostatin receptor (sst2) on tumor and neovascular-endothelial cells. We synthesized two conjugates containing the somatostatin analogue [Tyr3]-octreotate and Chlorin e6 (Ce6): Ce6-K3-[Tyr3]-octreotate (1) and Ce6-[Tyr3]-octreotate-K3-[Tyr3]-octreotate (2). Investigation of the uptake and photodynamic activity of conjugates in-vitro in human erythroleukemic K562 cells showed that conjugation of [Tyr3]-octreotate with Ce6 in conjugate 1 enhances uptake (by a factor 2) in cells over-expressing sst2 compared to wild-type cells. Co-treatment with excess free Octreotide abrogated the phototoxicity of conjugate 1 indicative of a specific sst2-mediated effect. In contrast conjugate 2 showed no receptor-mediated effect due to its high hydrophobicity. When compared with un-conjugated Ce6, the PDT activity of conjugate 1 was lower. However, it showed higher photostability which may compensate for its lower phototoxicity. Intra-vital fluorescence pharmacokinetic studies of conjugate 1 in rat skin-fold observation chambers transplanted with sst2+ AR42J acinar pancreas tumors showed significantly different uptake profiles compared to free Ce6. Co-treatment with free Octreotide significantly reduced conjugate uptake in tumor tissue (by a factor 4) as well as in the chamber neo-vasculature. These results show that conjugate 1 might have potential as an in-vivo sst2 targeting photosensitizer conjugate.

Prevalence of atopic diseases in patients with sarcoidosis.

It remains unclear whether atopy is associated with the occurrence of sarcoidosis or affects its severity. The purpose of this study was to compare the lifetime prevalence of atopic eczema, asthma, and hay fever in sarcoidosis patients with controls and to assess whether atopy influences the severity of sarcoidosis. The prevalence of atopic disorders assessed with a validated postal questionnaire in sarcoidosis patients with pulmonary, uveitis, and cutaneous sarcoidosis was compared with that of their domestic partners in a case-control study. The serological parameters, the pulmonary function tests, and the high-resolution computed tomography (HRCT) scans of atopic and nonatopic sarcoidosis patients were compared in a nested cohort. Multivariate logistic regression models were used to calculate the odds ratios (ORs) and the 95% confidence intervals (CIs). Two hundred twenty-five sarcoidosis patients and 177 controls were included. The prevalences of atopic eczema, asthma, and hay fever were comparable between patients and controls (12.4% versus 12.4%, 5.3% versus 5.6%, and 16.9% versus 15.8%, respectively). After adjusting for gender and ethnicity, those with sarcoidosis and a history of atopic eczema were significantly less likely to have uveitis (OR, 0.30; 95% CI, 0.13-0.71). Within the sarcoidosis cohort, the distributions of serological markers, the lung function tests, and the HRCT scans were similar between atopic and nonatopic patients. Atopy is not associated with the occurrence of sarcoidosis, but atopic eczema may decrease the likelihood of eye involvement.

Clinical manifestations of patients with intraocular inflammation and positive QuantiFERON-TB gold in-tube test in a country nonendemic for tuberculosis.

PURPOSE: To evaluate clinical manifestations of patients with uveitis and scleritis of unknown origin and positive QuantiFERON-TB Gold In-Tube test (quantiferon) in a country not endemic for tuberculosis. DESIGN: Multicenter retrospective cohort study. METHODS: Retrospective review of the clinical, laboratory, and imaging data of 77 patients. Main outcome measures consisted of ocular and systemic features as well as results of laboratory examinations. RESULTS: Out of all, 60 of 71 (85%) were living for at least 6 months in tuberculosis-endemic regions. Location of uveitis was variable; posterior uveitis (29/77; 38%) was the most frequent. Two clinical entities were commonly noted: retinal occlusive vasculitis (21/77; 27%) and serpiginoid choroiditis (11/77; 14%). Antituberculosis treatment was completed in 32 patients; 29 of them (91%) achieved complete remission. Mean quantiferon level was 7.5 U/mL; 71% had values above 2 U/mL and 41% above 10 U/mL. We observed no associations between quantiferon levels and clinical and/or imaging features. Previous tuberculosis infection was diagnosed in 5 of 77 patients (6.5%), while hilar/mediastinal lymphadenopathy was found in 25 of 76 patients (33%). Of these, 12 were consistent with the diagnosis of sarcoidosis, 9 were typical for (prior) tuberculosis, and 4 were compatible with both diagnoses. CONCLUSIONS: Ocular features of patients with idiopathic uveitis and positive quantiferon were diverse, but retinal occlusive vasculitis and serpiginoid choroiditis were common. The quantiferon levels were usually highly elevated and 33% of patients exhibited lymphadenopathy, suggesting frequently the diagnosis of sarcoidosis. Ocular inflammation reacted favorably to antituberculosis treatment, although only a small minority had documented (prior) tuberculosis.

Induction of apoptosis with hybrids of Arg-Gly-Asp molecules and peptides and antimitotic effects of hybrids of cytostatic drugs and peptides.

The presence of a high density of somatostatin receptors (SSRs) on human tumors forms the basis for the successful visualization of primary tumors and their metastases using radiolabeled somatostatin analogs. In recent years somatostatin analogs, coupled to beta-emitting radioisotopes, have been successfully applied in the treatment of patients with metastatic SSR-positive neuroendocrine tumors. This concept of targeting SSR-expressing tumors using peptide receptor radionuclide therapy may also apply to the use of somatostatin analogs coupled to chemotherapeutic compounds. Evidence for the effectiveness of such cytotoxic somatostatin analogs as antitumor agents has been provided in a significant number of studies in experimental tumor models. In addition to cytotoxic somatostatin analogs, somatostatin analogs coupled to peptides containing arginine, glycine, and aspartate and coupled to paclitaxel have been synthesized. Here we discuss the development of the different cytotoxic somatostatin analogs and their antitumor effects in vitro and in vivo in experimental models.

Increased cell death after therapy with an Arg-Gly-Asp-linked somatostatin analog.

UNLABELLED: Receptor-targeted scintigraphy and radionuclide therapy with radiolabeled somatostatin analogs are successfully applied for somatostatin receptor-positive tumors. The synergistic effects of an apoptosis-inducing factor, for example, the Arg-Gly-Asp (RGD) motif, can increase the radiotherapeutic efficacy of these peptides. Hence, the tumoricidal effects of the hybrid peptide RGD-diethylaminetriaminepentaacetic acid (DTPA)-Tyr3-octreotate (cyclic[c](Arg-Gly-Asp-D-Tyr-Asp)-Lys(DTPA)-D-Phe-c(Cys-Tyr-D-Trp-Lys-Thr-Cys)-Thr), hereafter referred to as RGD-DTPA-octreotate, were evaluated in comparison with those of RGD (c(Arg-Gly-Asp-D-Tyr-Asp)) and Tyr3-octreotate (D-Phe-c(Cys-Tyr-D-Trp-Lys-Thr-Cys)-Thr). METHODS: The therapeutic effects of RGD-111In-DTPA-octreotate, 111In-DTPA-RGD, and 111In-DTPA-Tyr3-octreotate were investigated with various cell lines by use of a colony-forming assay, and caspase-3 activity was also determined. RESULTS: Tumoricidal effects were found with 111In-DTPA-RGD, 111In-DTPA-Tyr3-octreotate, and RGD-111In-DTPA-octreotate, in order from least effective to most effective. Also, the largest increase in caspase-3 levels was found with RGD-111In-DTPA-octreotate. CONCLUSION: RGD-111In-DTPA-octreotate has more pronounced tumoricidal effects than 111In-DTPA-RGD and 111In-DTPA-Tyr3-octreotate, because of increased apoptosis, as indicated by increased caspase-3 activity.

Radiolabeled RGD-DTPA-Tyr3-octreotate for receptor-targeted radionuclide therapy.

The aim of this study was to develop and investigate a radiopeptide for the treatment of cancers which overexpress cell surface somatostatin receptors. The new radiopharmaceutical is composed of a somatostatin receptor-targeting peptide, a chelator (DTPA) to enable radiolabeling, and an apoptosis-inducing RGD (arginine-glycine-aspartate) peptide moiety. The receptor-targeting peptide portion of the molecule, Tyr3-octreotate, is specific for the somatostatin subtype-2 cell surface receptor (sst2), which is overexpressed on many tumor cells. Because of the rapid endocytosis of the somatostatin receptor, the entire molecule can thus be internalized, allowing the RGD portion to activate intracellular caspases, which in turn promotes apoptosis. In this paper, we present the synthesis and the in vitro and in vivo tumor binding and internalization characteristics of this hybrid peptide. In vitro internalization into sst2-positive tumor cells of the radiolabeled hybrid peptide appeared to be a rapid process and could be blocked by an excess of unlabeled octreotide, indicating an sst2-specific process. Tumor uptake in vivo in rats of radiolabeled RGD-DTPA-Tyr3-octreotate was in agreein vitro data and similar to that of radiolabeled DOTA-Tyr3-octreotate. The combined molecule is expected to significantly enhance the therapeutic efficacy of the somatostatin-based agent.

Somatostatin receptors in malignant lymphomas: targets for radiotherapy?

UNLABELLED: Somatostatin (SS) receptor (sst) scintigraphy is widely used in the visualization of neuroendocrine tumors expressing sst, and radiotherapy using radionuclide-labeled SS analogs has been introduced for treatment of patients with neuroendocrine tumors. Previous sst scintigraphy studies revealed that malignant lymphomas can also be visualized using this technique. The question has been addressed whether lymphomas might also be possible targets for radiotherapy using radionuclide-labeled SS analogs. Therefore, we investigated in vitro the characteristics of lymphoma tissues and lymphoid cell lines to evaluate whether lymphomas can be targets for radiotherapy. METHODS: Six orbital lymphomas, 2 Hodgkin's lymphomas, and 2 non-Hodgkin's lymphomas from the neck region were collected. Reverse transcriptase polymerase chain reaction (RT-PCR) and quantitative RT-PCR were performed to detect and quantify the expression of sst(1-5) mRNA. Receptor autoradiography studies using [(125)I-Tyr(3)]octreotide were performed to evaluate binding to sst on cryostat sections of lymphomas. Immunohistochemistry was used to investigate expression of sst(2) and sst(3). Membrane binding studies and in vitro internalization experiments using [(125)I-Tyr(3)]octreotide were performed to study binding and uptake of [(125)I-Tyr(3)]octreotide by lymphoid cell lines (JY, TMM, APD) and primary cells derived from a B-cell-derived chronic lymphatic leukemia. RESULTS: A selective expression of sst(2) and sst(3) messenger RNA (mRNA) was demonstrated. By quantitative RT-PCR, expression levels of sst(2) and sst(3) mRNA were relatively low. Autoradiography studies revealed low binding of [(125)I-Tyr(3)]octreotide, whereas immunoreactivity could not be detected for sst(2) and sst(3) by immunohistochemistry. On the lymphoid cell lines only low numbers of high-affinity SS binding sites were found. In vitro, uptake of [(125)I-Tyr(3)]octreotide by these cells was also very low. CONCLUSION: On the basis of our findings, we conclude that lymphomas do not appear to be candidates for radiotherapy using radionuclide-labeled SS analogs. However, lymphomas are highly radiosensitive tumors and further clinical studies should be performed to evaluate whether the low receptor density is sufficient for targeting treatment in these tumors.

In vivo and in vitro detection of dopamine d2 receptors in uveal melanomas.

Scintigraphy with radiolabeled benzamides was used in melanoma patients. Studies with a newer benzamide called 123I-epidepride, a high-affinity D2 receptor (D2R) antagonist, showed high sensitivity in D2R-positive pituitary adenomas. We evaluated the presence of D2R in patients with uveal melanomas in vivo with 123I-epidepride, and in vitro in melanomas, using immunohistochemistry (IHC) and 125I-epidepride autoradiography. We studied the in vivo tumor-to-background (TB) ratios in six patients with posterior uveal melanoma (one previously enucleated). IHC was performed in 3 of 6 tumors after enucleation and in another 20 uveal melanomas, 7 metastatic lymph nodes from skin melanoma, and 2 normal specimens. 125I-epidepride autoradiography was performed in 10 uveal melanomas (3 of which were studied in vivo), 7 metastases, and 2 normal samples. Radioligand uptake was present in the affected eye of 5 patients with uveal melanoma (TB = 3.1-6.1) and absent in the operated one (TB = 1). Eight uveal tumors were positive at IHC (35%), 14 weakly positive (61%), and 1 negative (4%). Two metastases were positive (29%), 2 weakly positive (29%), and 3 negative (42%). Two uveal tumors were positive at autoradiography (20%), 7 had nonspecific binding (70%), and 1 was negative (10%). One metastasis was positive (14%), while 6 were negative (86%). 123I-epidepride scintigraphy in uveal melanomas seems promising for sensitivity and image quality. D2R was demonstrated in a significant proportion of the melanomas, although 123I-epidepride uptake might also be nonspecific and unrelated to D2R binding. Although further studies on larger series are needed, 123I-epidepride could represent a future tool to study the expression of D2R in other classes of neuroendocrine tumors.