Factor VIII inhibitor development in Egyptian hemophilia patients: does intron 22 inversion mutation play a role?

Relationship between mutations in severe hemophilia A and risk of inhibitor development: A large single-center study

BACKGROUND

One of the major problems for patients with severe hemophilia A (HA) is the development of neutralizing antibodies against factor VIII. This study aimed to analyze the molecular and clinical profiles of patients with severe HA and to determine if certain genetic variants predispose to inhibitor development in these patients.

METHODS

A single-center study was conducted among patients with severe HA between March 20, 2000, and June 31, 2023. Demographic data and laboratory results of patients were collected. The inverse-shifting PCR (IS-PCR) technique was initially used to screen patients for intron 22 and 1 inversions (Inv-22 and Inv-1).

RESULTS

A total of 480 patients with severe HA (408 without inhibitors and 72 with inhibitors) were enrolled in this study. The median age of the patients at the time of diagnosis was 6 months (IQR: 3 months to 18 months). Inv-22 was observed in 199 (41.5 %) of the cases. Among those patients who developed inhibitors, 53 (73.6 %) were classified as high-titer and 19 (26.4 %) as low-titer. Inv-22, positive family history of inhibitor formation, and history of intense injections revealed a statistically significant association with the risk of inhibitor development.

CONCLUSION

The results of this study confirm the important role of different genetic variants, family history of inhibitor formation, and history of intense injections for the formation of inhibitors in patients with severe HA. This would allow us to stratify the patients which can have important clinical implications, especially in terms of their management and outcome.

Nonneutralizing antibodies in Nordic persons with moderate hemophilia A and B (the MoHem study)

Background

The impact of nonneutralizing antibodies (NNAs) in moderate hemophilia is elusive.

Objectives

To explore the presence of NNAs in Nordic persons with moderate hemophilia A (MHA) and B (MHB) in relation to treatment modality, clinical outcome, history of inhibitor, and the corresponding factor VIII (FVIII)/factor IX (FIX) gene mutation.

Methods

A cross-sectional multicenter study covering persons with MHA and MHB in Sweden, Finland, and Norway. Inhibitors were analyzed with the Bethesda assay, and NNAs were detected by enzyme-linked immunosorbent assay.

Results

Plasma samples from 137 MoHem study participants (median age 29 years; Q1-Q3, 15-54) were analyzed. NNAs were present in 11 of 82 (13%) of people with MHA and 7 of 55 (13%) of those with MHB irrespective of prophylactic or on-demand treatment, most frequently after 150 exposure days (EDs). Three NNA positive patients had a history of high-titer inhibitor, but current analyses were negative (<0.6 BU/mL). Baseline FVIII/FIX activity was similar among NNA positive and negative patients. Current bleeding rates were low, but patients with NNAs captured a higher Hemophilia Joint Health Score (7 [median]; Q1-Q3, 3-20 vs. 4; 1-9) (P = .02) and had more frequently undergone arthroplasty or arthrodesis (5 [33%] vs. 15 [13%]) (P = .03).

Conclusion

NNAs were detected in 13% of Nordic persons with MHA and MHB, most frequently after 150 EDs. Patients with NNAs had more severe hemophilic arthropathy than patients without NNAs. The relationship between NNAs and clinical outcome in hemophilia should be further explored in a large cohort including pharmacokinetics and longitudinal observations with repeated blood sampling.

Self-Organization of Sinusoidal Vessels in Pluripotent Stem Cell-derived Human Liver Bud Organoids

The induction of tissue-specific vessels in in vitro living tissue systems remains challenging. Here, we directly differentiated human pluripotent stem cells into CD32b+ putative liver sinusoidal progenitors (iLSEP) by dictating developmental pathways. By devising an inverted multilayered air-liquid interface (IMALI) culture, hepatic endoderm, septum mesenchyme, arterial and sinusoidal quadruple progenitors self-organized to generate and sustain hepatocyte-like cells neighbored by divergent endothelial subsets composed of CD32blowCD31high, LYVE1+STAB1+CD32bhighCD31lowTHBD-vWF-, and LYVE1-THBD+vWF+ cells. Wnt2 mediated sinusoidal-to-hepatic intercellular crosstalk potentiates hepatocyte differentiation and branched endothelial network formation. Intravital imaging revealed iLSEP developed fully patent human vessels with functional sinusoid-like features. Organoid-derived hepatocyte- and sinusoid-derived coagulation factors enabled correction of in vitro clotting time with Factor V, VIII, IX, and XI deficient patients' plasma and rescued the severe bleeding phenotype in hemophilia A mice upon transplantation. Advanced organoid vascularization technology allows for interrogating key insights governing organ-specific vessel development, paving the way for coagulation disorder therapeutics.

Management of haemophilia A with inhibitors: A regional cross-talk

INTRODUCTION

The development of inhibitors with factor VIII (FVIII) replacement therapy is one of the most common and challenging complications of haemophilia A (HA) treatment, jeopardising treatment efficacy and predisposing patients to high risks of morbidity and mortality. The management of patients with inhibitors is particularly challenging in countries where resources are limited.

AIM

To provide a comprehensive summary of the management of HA with inhibitors while focusing on differences in practice between Western and non-Western countries and how resource scarcity can impact HA management, leading to suboptimal outcomes in patients with inhibitors.

METHODS

Summary of key evidence and regional expert opinion.

RESULTS

We address, particularly, the diagnosis of and testing for inhibitors, as well as the epidemiology of inhibitors, including incidence, prevalence and disease burden. Secondly, we provide an overview of the current treatment landscape in HA with inhibitors regarding the eradication of inhibitors with immune tolerance induction and the treatment and prevention of bleeding with bypassing agents, non-factor replacement agents and other experimental therapies. This is complemented with insights from the authors around the applicability of, and challenges associated with, such therapies in their settings of practice.

CONCLUSIONS

We conclude by proposing some key steps towards bridging the gaps in the management of HA with inhibitors in resource-limited countries, including: (1) the collection of quality data that can inform healthcare reforms and policies; (2) improving disease knowledge among healthcare practitioners and patients with the aim of standardising disease management across centres and (3) working towards promoting equal access to HA care and therapies for everyone.

The presence of living endometrial cells in ovarian endometriotic cyst fluid may contribute to the recurrence of endometriosis after surgical excision of endometriomas

BACKGROUND

Many factors can affect the recurrence of endometriosis after surgery, however, whether endometriotic cyst fluid contributes to endometriosis recurrence after surgical excision of ovarian endometriomas remains unclear. The objective of this study was to determine the presence of endometrial cells in ovarian endometriosis cyst fluid and the potential differences between these cells and those in the cyst wall.

METHODS

Samples of cyst fluid (n = 39) and drainage fluid (n = 14) were collected from patients with ovarian endometriomas undergoing laparoscopic surgery. Drainage fluid from 14 patients without endometriosis was used as a control. The presence of endometrial cells in cyst fluid and drainage fluid was determined by cell culture in vitro and immunostaining. In addition, cyst fluid endometrial fragments and viscosity were analysed by transcriptome sequencing analysis and apparent diffusion coefficients, respectively. An animal model was used to confirm the ability of endometrial cells in cyst fluid to form new lesions.

RESULTS

We found endometrium-like tissues in 71.8% (28/39) of cyst fluid and 71.4% (10/14) of drainage fluid samples by histopathological examination, and the presence of endometrioid tissue in cyst fluid was related to the viscosity of the cyst fluid. The living endometrial cells in cyst fluid and drainage fluid were confirmed by cell culture in vitro and immunostaining. Moreover, the adhesion ability of endometrial fragments in cyst fluid was significantly higher than that of ectopic tissues in the cyst wall (P < 0.05). In addition, living endometrial cells in the cyst fluid were able to adhere and alive in the animal model.

CONCLUSIONS

The existence of living endometrial cells with high adhesion ability in ovarian endometriotic cyst fluid may contribute to the recurrence of endometriosis after surgical excision of endometriomas due to cyst fluid outflow during the surgical procedure.

Hemophilia in the south of Tunisia

Hemophilia is a rare constitutional hemorrhagic disorder. There is insufficient epidemiological data on hemophilia in Tunisia. To describe the epidemiological, clinical, therapeutic, and outcome of a cohort of patients with hemophilia in southern Tunisia. A retrospective study was conducted on patients with hemophilia at the Hemophilia Treatment Center of Southern Tunisia in Sfax over 38 years (from January 1982 to December 2020). Data were collected in a regional hemophilia registry of the South Tunisian center. We collected 141 cases of hemophilia, 85% of whom had hemophilia A and 15% had hemophilia B. The severe form represented 65%, followed by the moderate form at 25%. The prevalence of hemophilia was 4.4 in 100 000 population. Family history of hemophilia was found in 70%. The mean age of patients at diagnosis was 28 months. Hemophilia was detected in 87% of cases after hemorrhagic syndrome. Bleeding occurred mainly in hemarthrosis (73%), hematoma (70%), and visceral bleeding (28%). Intracranial bleeding occurred in 6% of cases. Thirty-six percent of patients were on prophylactic therapy. Hemophilic arthropathy was the most important orthopedic complication in our patients (38%). Inhibitory antibodies occurred in 16% of PWH. Transfusion-transmitted infections with HIV and hepatitis C were in 2 and 31% of cases, respectively. The prevalence of hemophilia is still underestimated in our center. The severe form of hemophilia is the most frequent. Hemophilic arthropathy was the most important complication in our patients. This showed that hemophilia is still a disabling disease in our country.

Determining common variants in patients with haemophilia A in South Vietnam and screening female carriers in their family members

AIMS

The aim of this study was to determine common variants in F8, including intron 22 inversion (Inv22), intron 1 inversion (Inv1) and point mutations, the transmission of these variants between patients with haemophilia A (HA) and their family members.

METHODS

Genetic analysis was conducted in 71 patients who were clinically diagnosed with HA and 152 related female members in South Vietnam by a combination of inversion PCR (I-PCR), multiplex PCR and direct sequencing.

RESULTS

Variants in F8, including Inv22, point mutations (with 37 genotypes) and two novel variants, occupied 60 patients with HA. Among severe patients, the rate of Inv22 was 44%. Missense was the common point mutation of over 50% in patients with moderate HA and mild HA. Inv1 was absent in all patients. F8 variants were also found in 119 female carriers (FCs) (78.3%) from families related to patients with HA. There were 56 mothers (93.3%) carrying F8 variants and passing the same variants to their sons.

CONCLUSIONS

These findings were the first to provide important information about the presence of Inv22 and point mutation in Vietnamese patients with HA, the mothers and their female family members. It demonstrated that genetic diagnosis and counselling for HA carriers were essential factors for future improvements in comprehensive and equitable healthcare polices for patients with HA and FCs in Vietnam.

Efficacy, safety, and immunogenicity of rurioctocog alfa pegol for prophylactic treatment in previously treated patients with severe hemophilia A: a systematic review and meta-analysis of clinical trials

Background: Patients with severe hemophilia often present with painful joint and soft tissue bleeding which may restrict them from their daily activities. The current standard of care still relies on a regular prophylactic factor VIII (FVIII), which has a high daily treatment burden. Recently, rurioctocog alfa pegol, a third-generation recombinant FVIII with a modification in its polyethylene glycol (PEG) component, has been developed. Several trials have studied this synthetic drug as bleeding prophylaxis in severe hemophilia A. This study aims to evaluate the efficacy, safety, and immunogenicity of rurioctocog alfa pegol for previously treated patients with severe hemophilia A. Methods: This study was conducted in conformity with the PRISMA guidelines. Data were retrieved from PubMed, Scopus, Cochrane Library, Wiley Online Library, and CINAHL (via EBSCOhost). Study qualities were assessed using the Methodological Index for Non-Randomized Studies (MINORS) and Modified Jadad scales. Results: Four studies involving 517 previously treated severe hemophilia A patients were included in this study. The pooled mean of total annualized bleeding rate (ABR) and hemostatic efficacy was 2.59 (95% CI = 2.04-3.14) and 92% (95% CI = 85%-97%), respectively. Only 30 (2.3%) non-serious and one (1.4%) serious adverse events were considered related to rurioctocog alfa pegol treatment. At the end of the studies, no development of FVIII inhibitory antibodies was observed. None of the developed binding antibodies to FVIII, PEG-FVIII, or PEG was correlated to the treatment efficacy and safety. Conclusions: Despite the limited availability of direct comparison studies, our analyses indicate that rurioctocog alfa pegol could serve as a safe and effective alternative for bleeding prophylaxis in previously treated hemophilia A patients. Moreover, it appears to have low immunogenicity, which further increases the safety profile of the drug in such clinical conditions.