Plasminogen deficiency

[Ligneous conjunctivitis]

CASE REPORT

We report the case of a 3-year-old female patient with therapy refractive recurrent conjunctivitis and membrane formation of the upper eyelid. After surgical removal the histological examination showed an image compatible with ligneous conjunctivitis. A manifest serum plasminogen deficiency (22 %) supported the diagnosis.

TREATMENT

The treatment with corticosteroids, heparin-containing and fresh frozen plasma (FFP) eye drops, renewed surgical ablation with perioperative intravenous FFP administration and local cyclosporine A eye drops achieved a stable condition with low disease activity.

CONCLUSION

The combination of these therapy approaches has been performed here for the first time and has not been described in the literature so far.

High-level expression, purification, and enzymatic characterization of truncated human plasminogen (Lys531-Asn791) in the methylotrophic yeast Pichia pastoris

Background

Plasmin is a serine protease that plays a critical role in fibrinolysis, which is a process that prevents blood clots from growing and becoming problematic. Recombinant human microplasminogen (rhμPlg) is a derivative of plasmin that solely consists of the catalytic domain of human plasmin and lacks the five kringle domains found in the native protein. Developing an industrial production method that provides high yields of this protein with high purity, quality, and potency is critical for preclinical research.

Results

The human microplasminogen gene was cloned into the pPIC9K vector, and the recombinant plasmid was transformed into Pichia pastoris strain GS115. The concentration of plasmin reached 510.1 mg/L of culture medium. Under fermentation conditions, the yield of rhμPlg was 1.0 g/L. We purified rhμPlg to 96 % purity by gel-filtration and cation-exchange chromatography. The specific activity of rhμPlg reached 23.6 U/mg. The K_m of substrate hydrolysis by recombinant human microplasmin was comparable to that of human plasmin, while rhμPlm had higher k_cat/Km values than plasmin. The high purity and activity of the rhμPlg obtained here will likely prove to be a valuable tool for studies of its application in thrombotic diseases and vitreoretinopathies.

Conclusions

Reliable rhμPlg production (for use in therapeutic applications) is feasible using genetically modified P. pastoris as a host strain. The successful expression of rhμPlg in P. pastoris lays a solid foundation for its downstream application.

Electronic supplementary material

The online version of this article (doi:10.1186/s12896-015-0179-z) contains supplementary material, which is available to authorized users.

Ligneous conjunctivitis in a patient of juvenile colloid milia: A rare association

We present to you, case of a 10-year-old female with h/o redness, watering since 8 months. Her vision was 20/30 in right eye and 20/70 in left eye. Conjunctiva had plenty of purulent discharge and palpebral conjunctiva was studded with membranous lesions. She was found to have multiple hyperpigmented papulopustular lesions over face, palms and legs. She was started with topical moxifloxacin and lubricating drops. Patient was followed-up after 15 days. At that time her conjunctiva had formation of a woody pseudomembrane. Excision of the lesions and skin biopsy was done and sent for hislopathological examination. Findings of histopathological examination were suggestive of ligneous conjunctivitis and juvenile colloid milia. We have started this patient with long-term cyclosporine drops and tear supplements. In next visit, the membrane was resolved. Hence, we continued with the same treatment, but again the woody membrane recurred.

Periodontitis associated with plasminogen deficiency: a case report

BACKGROUND

Plasminogen deficiency is a rare autosomal recessive disease, which is associated with aggressive periodontitis and gingival enlargement. Previously described treatments of plasminogen deficiency associated periodontitis have shown limited success. This is the first case report indicating a successful therapy approach consisting of a non-surgical supra- and subgingival debridement in combination with an adjunctive systemic antibiotic therapy and a strict supportive periodontal regimen over an observation period of 4 years.

CASE PRESENTATION

The intraoral examination of a 17-year-old Turkish female with severe plasminogen deficiency revealed generalized increased pocket probing depths ranging from 6 to 9 mm, bleeding on probing over 30%, generalized tooth mobility, and gingival hyperplasia. Alveolar bone loss ranged from 30% to 50%. Clinical attachment loss corresponded to pocket probing depths. Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Prevotella nigrescens and Eikenella corrodens have been detected by realtime polymerase chain reaction. Periodontal treatment consisted of full mouth disinfection and adjunctive systemic administration of amoxicillin (500 mg tid) and metronidazole (400 mg tid). A strict supportive periodontal therapy regimen every three month in terms of supra- and subgingival debridement was rendered. The reported therapy has significantly improved periodontal health and arrested disease progression. Intraoral examination at the end of the observation period 3.5 years after non-surgical periodontal therapy showed generalized decreased pocket probing depths ranging from 1 to 6 mm, bleeding on probing lower 30%, and tooth mobility class I and II. Furthermore, microbiological analysis shows the absence of Porphyromonas gingivalis, Prevotella intermedia and Treponema denticola after therapy.

CONCLUSION

Adjunctive antibiotic treatment may alter the oral microbiome and thus, the inflammatory response of periodontal disease associated to plasminogen deficiency and diminishes the risk of pseudomembrane formation and progressive attachment loss. This case report indicates that patients with plasminogen deficiency may benefit from non-surgical periodontal treatment in combination with an adjunctive antibiotic therapy and a strict supportive periodontal therapy regimen.

Fibrinolysis and the control of blood coagulation

Fibrin plays an essential role in hemostasis as both the primary product of the coagulation cascade and the ultimate substrate for fibrinolysis. Fibrinolysis efficiency is greatly influenced by clot structure, fibrinogen isoforms and polymorphisms, the rate of thrombin generation, the reactivity of thrombus-associated cells such as platelets, and the overall biochemical environment. Regulation of the fibrinolytic system, like that of the coagulation cascade, is accomplished by a wide array of cofactors, receptors, and inhibitors. Fibrinolytic activity can be generated either on the surface of a fibrin-containing thrombus, or on cells that express profibrinolytic receptors. In a widening spectrum of clinical disorders, acquired and congenital defects in fibrinolysis contribute to disease morbidity, and new assays of global fibrinolysis now have potential predictive value in multiple clinical settings. Here, we summarize the basic elements of the fibrinolytic system, points of interaction with the coagulation pathway, and some recent clinical advances.

Switch from protective to adverse inflammation during influenza: viral determinants and hemostasis are caught as culprits

Influenza viruses cause acute respiratory infections, which are highly contagious and occur as seasonal epidemic and sporadic pandemic outbreaks. Innate immune response is activated shortly after infection with influenza A viruses (IAV), affording effective protection of the host. However, this response should be tightly regulated, as insufficient inflammation may result in virus escape from immunosurveillance. In contrast, excessive inflammation may result in bystander lung tissue damage, loss of respiratory capacity, and deterioration of the clinical outcome of IAV infections. In this review, we give a comprehensive overview of the innate immune response to IAV infection and summarize the most important findings on how the host can inappropriately respond to influenza.

The association between anti-plasminogen antibodies and disease activity in ANCA-associated vasculitis

OBJECTIVE

Previous studies have shown that in patients with ANCA-associated vasculitis (AAV), anti-plasminogen antibodies were associated with reduced renal function and the presence of fibrinoid necrosis and cellular crescents in renal histology. The purpose of the current study was to investigate whether anti-plasminogen antibodies are associated with the systemic disease activity of AAV.

METHODS

One hundred and four Chinese patients with AAV were recruited. Anti-plasminogen antibodies were detected in sequential serum samples at initial onset and remission of the disease. Associations of anti-plasminogen antibodies with clinicopathological parameters were analysed.

RESULTS

The prevalence of anti-plasminogen antibodies was significantly higher in AAV patients than in healthy controls (19/104 vs 0/50, χ(2) = 8.8, P = 0.003). The prevalence of anti-plasminogen antibodies was significantly higher in the active stage of AAV than in remission (19/104 vs 1/48, χ(2) = 7.5, P = 0.013). The level of anti-plasminogen antibodies (expressed as a percentage of the positive controls) correlated with the ESR (r = 0.207, P = 0.042), serum creatinine (r = 0.302, P = 0.002), d-dimer (r = 0.273, P = 0.009) and the percentage of glomeruli with crescents in renal specimens (r = 0.393, P = 0.004). The level of Birmingham vasculitis activity scores and the prevalence of arthralgia and gastrointestinal involvement in patients with anti-plasminogen antibodies were significantly higher than in patients without anti-plasminogen antibodies [22.5 (s.d. 5.63) vs. 19.4 (s.d. 4.66), P = 0.015; 63.2% vs. 25.8%, P = 0.002; 57.9% vs. 21.1%, P = 0.001, respectively].

CONCLUSION

Circulating anti-plasminogen antibodies were associated with systemic disease activity and renal disease activity of AAV.

Conjunctival instillation of plasminogen eliminates ocular lesion in B6.129P2-Plg(tm1Jld) transgenic mice, a model of ligneous conjunctivitis

Ligneous conjunctivitis is a severe and rare chronic "idiopathic membraneous" conjunctivitis, characterized by the formation of pseudomembranes mostly on the palpebral surfaces that progressively replace the normal mucosa. Evidence has been provided that ligneous conjunctivitis is caused by a severe systemic plasminogen deficiency with decreased plasminogen antigen and decreased plasminogen functional activities. Objective of the present study is to verify the hypothesis that a topical eye application of plasminogen is able to ameliorate the consequences of this disease. Here we report the results of pre-clinical studies performed to investigate the therapeutic effectiveness of an eye-drop plasminogen preparation in B6.129P2-Plg(tm1Jld) transgenic mice, a model of ligneous conjunctivitis. The entity of protection mediated by plasminogen was evaluated by measuring the extent of the eye lesion by means of a computerized system and dedicated software. The results of the present study clearly showed that the administration for six times a day of plasminogen eye-drop solution in the lesioned eye of animals knock-out for plasminogen gene and developing ligneous conjunctivitis caused a dose and time related reduction of the extent of the ocular lesion. These findings may pave the road for the pharmacological treatment of the ocular lesion associated to the ligneous conjunctivitis that at the present is surgically treated by removing the pseudomembranes generated on the eye.

Gender affects skin wound healing in plasminogen deficient mice

The fibrinolytic activity of plasmin plays a fundamental role in resolution of blood clots and clearance of extravascular deposited fibrin in damaged tissues. These vital functions of plasmin are exploited by malignant cells to accelerate tumor growth and facilitate metastases. Mice lacking functional plasmin thus display decreased tumor growth in a variety of cancer models. Interestingly, this role of plasmin has, in regard to skin cancer, been shown to be restricted to male mice. It remains to be clarified whether gender also affects other phenotypic characteristics of plasmin deficiency or if this gender effect is restricted to skin cancer. To investigate this, we tested the effect of gender on plasmin dependent immune cell migration, accumulation of hepatic fibrin depositions, skin composition, and skin wound healing. Gender did not affect immune cell migration or hepatic fibrin accumulation in neither wildtype nor plasmin deficient mice, and the existing differences in skin composition between males and females were unaffected by plasmin deficiency. In contrast, gender had a marked effect on the ability of plasmin deficient mice to heal skin wounds, which was seen as an accelerated wound closure in female versus male plasmin deficient mice. Further studies showed that this gender effect could not be reversed by ovariectomy, suggesting that female sex-hormones did not mediate the accelerated skin wound healing in plasmin deficient female mice. Histological examination of healed wounds revealed larger amounts of fibrotic scars in the provisional matrix of plasmin deficient male mice compared to female mice. These fibrotic scars correlated to an obstruction of cell infiltration of the granulation tissue, which is a prerequisite for wound healing. In conclusion, the presented data show that the gender dependent effect of plasmin deficiency is tissue specific and may be secondary to already established differences between genders, such as skin thickness and composition.

Laryngeal obstruction in congenital plasminogen deficiency

Type 1 congenital plasminogen deficiency (CPD) is a rare autosomal recessive disease which causes formation of fibrin pseudomembranes that affect multiple systems/organs: the eyes, respiratory system, urinary and genital systems, gastrointestinal system, and the central nervous system. We present a rare manifestation of the disease-severe upper airway obstruction due to a rapidly growing mass in the supraglottic region-6 months after dental treatment under general anesthesia. The management of such a manifestation has not been discussed in the current literature. Due to deterioration in his clinical status, the patient eventually underwent both a tracheotomy in order to bypass the obstruction, and excision of the supraglottic mass. Within a few days the mass recurred with complete obstruction of the upper airway.

Plasmin-driven fibrinolysis facilitates skin tumor growth in a gender-dependent manner

Rearrangement of the skin during wound healing depends on plasmin and plasminogen, which serve to degrade fibrin depositions in the provisional matrix and thereby facilitate keratinocyte migration. In the current study, we investigated whether plasmin and plasminogen likewise played a role during the development of skin cancer. To test this, we set up a chemically induced skin tumor model in a cohort of mice and found that skin tumor growth in Plg(-/-) male mice was reduced by 52% compared with wild-type controls. Histological analyses suggested that the growth-restricting effect of plasminogen deficiency was due to thrombosis and lost patency of the tumor vasculature, resulting in tumor necrosis. The connection between plasmin-dependent fibrinolysis, vascular patency, and tumor growth was further substantiated as the effect of plasminogen deficiency on tumor growth could be reverted by superimposing heterozygous fibrinogen deficiency on Plg(-/-) mice. Tumors derived from these Fib(-/+);Plg(-/-) mice displayed a significantly decreased level of tumor thrombosis compared with Plg(-/-) mice. In summary, these data indicate that plasmin-driven fibrinolysis facilitates tumor growth by maintaining patency of the tumor vasculature.

Rare coagulation disorders: a retrospective analysis of 156 patients in Turkey

Objective: To retrospectively evaluate the clinical findings, laboratory data, management, and outcome in a group ofTurkish children diagnosed with rare coagulation deficiencies (RCDs) between January 1999 and June 2009.

Material and Methods: The Turkish Society of Pediatric Hematology-Hemophilia-Thrombosis-Hemostasissubcommittee designed a Microsoft Excel-based questionnaire for standardized data collection and sent it to participatinginstitutions.

Results: In total, 156 patients from 12 pediatric referral centers were included in the study. The cost common RCDswere as follows: FVII (n = 53 [34%]), FV (n = 24 [15.4%]), and FX (n = 23 [14.7%]) deficiency. The most common initialfinding in the patients was epistaxis, followed by ecchymosis, and gingival bleeding.

Conclusion: Initial symptoms were mucosal bleeding, and fresh frozen plasma (FFP) and tranexamic acid werethe most commonly used treatments. We think that prophylactic treatment used for hemophilia patients should beconsidered as an initial therapeutic option for patients with rare factor deficiencies and a severe clinical course, and forthose with a factor deficiency that can lead to severe bleeding.

Knowledge and therapeutic gaps: a public health problem in the rare coagulation disorders population

Rare coagulation disorders (RCDs) present a considerable and multifaceted public health risk. Although inherited RCDs affect a minor segment of any local healthcare delivery system, their global impact is major and highlight the challenges of delivering healthcare services to any rare disease population. These include but are not limited to: (1) a general lack of knowledge about and familiarity with the genetic and clinical implications of the disorder among affected patients, and both urgent and specialty care providers; (2) the potential for preventable morbidity and mortality related to delayed diagnosis and treatment; (3) the lack of safe and effective therapies; and (4) minimal research activity to establish and improve standards of care. A multiagency national partnership has established an approach to address these problems through development of a clinical, genetic, and treatment-related web-based data-collection tool that will: (1) generate a reliable, sufficient knowledge base for these disorders; (2) facilitate new product licensure through subject identification and access to comparative historical treatment data; and (3) serve as an effective tool for outcomes research and post-licensure product surveillance. To maximize impact, this database is being harmonized with a European data-collection effort. Database development and harmonization is in progress. A resource library was completed and disseminated to major national and international bleeding disorder websites to provide state-of-the-art patient and provider education on each RCD. We believe that this model is effective and adaptable to other rare conditions.

Plasminogen deficiency attenuates postnatal erythropoiesis in male C57BL/6 mice through decreased activity of the LH-testosterone axis

Novel roles for the serine protease plasmin have been implicated recently in physiological and pathological processes. However, whether plasmin is involved in erythropoiesis is not known. In the present study, we studied the consequences of plasminogen deficiency on erythropoiesis in plasminogen-deficient (Plg knockout [KO]) mice. Erythroid differentiation was attenuated in male Plg KO mice and resulted in erythroblastic accumulation within the spleen and bone marrow, with increased apoptosis in the former, erythrocytosis, and splenomegaly, whereas similar erythropoietic defect was less prominent in female Plg KO mice. In addition, erythrocyte lifespan was shorter in both male and female Plg KO mice. Erythropoietin levels were compensatory increased in both male and female Plg KO mice, and resulted in a higher frequency of burst-forming units-erythroid within the spleen and bone marrow. Surprisingly, we found that male Plg KO mice, but not their female counterparts, exhibited normochromic normocytic anemia. The observed sex-linked erythropoietic defect was attributed to decreased serum testosterone levels in Plg KO mice as a consequence of impaired secretion of the pituitary luteinizing hormone (LH) under steady-state condition. Surgical castration causing testosterone deficiency and stimulating LH release attenuated erythroid differentiation and induced anemia in wild-type animals, but did not further decrease the hematocrit levels in Plg KO mice. In addition, complementation of LH using human choriogonadotropin, which increases testosterone production, improved the erythropoietic defect and anemia in Plg KO mice. The present results identify a novel role for plasmin in the hormonal regulation of postnatal erythropoiesis by the LH-testosterone axis.

Management of ligneous conjunctivitis in a child with plasminogen deficiency

Plasminogen deficiency, a rare autosomal recessive disorder, is classified as type I (hypoplasminogenemia) or type II (dysplasminogenemia). Hypoplasminogenemia is characterized by impaired wound healing while ligneous conjunctivitis (LC) is its main manifestation presenting with redness of the conjunctivae and progression to pseudomembranes' formation on the palpebral surfaces. A 4-year-old girl with LC in her left eye and impaired vision was referred to our unit. The conjunctival membranes had been already excised twice, followed by recurrences. Soon after the third recurrence, a probable diagnosis of LC was suggested, confirmed by a reduced plasminogen activity at 20% (normal values 80-120%). Both of her parents have slightly reduced plasminogen levels (50-60%) without any relevant symptom. Fresh frozen plasma (FFP) was administered systemically and topically, initiating 2 days before surgical removal of pseudomembranes with electrocautery under general anaesthesia. Systemic FFP was administered for 12 days postoperatively, along with topical use; the later was continued thereafter for 3 months. No recurrence was noticed. The vision was improved. Two weeks after cessation of the topical treatment, pseudomembranes reappeared. Topical application of FFP was reinitiated soon thereafter, and the girl underwent a second operation to have the conjunctival pseudomembranes removed. The perioperative therapeutic management was as previously described. Systemic treatment was stopped at the end of the tenth day while topical application of FFP was being continued until now, 10 months postoperatively. No recurrence has been observed and the vision remains at 9/10.

CONCLUSION

Since surgical excision of the conjunctival pseudomembranes alone in patients with LC does not protect from recurrences, the perioperative administration of FFP, both systemically and topically improves the outcome. Furthermore, the long-term application of topical FFP preparations seems to prevent recurrences and has a protective effect on the vision of these patients.

Destructive membranous periodontal disease (ligneous gingivitis): a literature review

BACKGROUND

Destructive membranous periodontal disease, or ligneous gingivitis, is a rare condition involving nodular gingival enlargement with ulceration and periodontal tissue destruction. This review gives a brief account of the cases reported in the literature. An effort is also made to define the periodontal disease caused by plasminogen deficiency with a view to its potential inclusion in the classification of periodontal diseases.

METHODS

A MEDLINE/PubMed and manual search was conducted to find papers describing ≥1 case of ligneous disease involving the oral mucosa.

RESULTS

We identified 23 articles reporting 35 cases. For each patient, we analyzed various characteristics, including age, sex, age of onset, oral symptoms, histologic features, plasminogen levels (functional activity, plasma antigen), genetic features, treatment, and results of treatment during the reported follow-up.

CONCLUSIONS

Ligneous gingivitis is a rare periodontal disorder closely associated with ligneous conjunctivitis and plasminogen deficiency. Its diagnosis may be supported by the finding of genetic mutations responsible for the condition. Research is focusing on the future development of an effective therapy capable of arresting the destructive evolution of the disease. Additional studies, investigating features such as probing depth and attachment loss, are needed for the appropriate classification of this periodontal disease.

Life-threatening hemorrhage and prolonged wound healing are remarkable phenotypes manifested by complete plasminogen activator inhibitor-1 deficiency in humans

BACKGROUND

 Plasminogen activator inhibitor-1 (PAI-1) is the primary physiological regulator of urokinase plasminogen activator (uPA) and tissue plasminogen activator (tPA) activity. A number of studies have shown that elevated levels of PAI-1 are related to pathological states such as an increased risk of arterial thrombotic events and a poor prognosis for cancer patients; however, there are few reports about PAI-1 deficiency in humans because the disorder is very rare.

OBJECTIVE

 To understand the in vivo impact of a complete PAI-1 deficiency, Serpine1(-/-) mice were generated; a number of in vivo studies have been conducted to elucidate the function of PAI-1 using Serpine1(-/-) mice. The phenotypes demonstrated in Serpine1(-/-) mice, however, were quite different from those in humans. Therefore, it is necessary to find out and analyze SERPINE1 deficiency in humans.

PATIENT AND METHODS

 The patient is a 47-year-old woman who has had multiple episodes of major bleeding. Although most of the patient's blood coagulation factors were functionally normal, her PAI-1 antigen levels were undetectable. Therefore, DNA sequencing of the SERPINE1 gene were analyzed.

RESULTS

 The proband had a homozygous 1-bp duplication (C) at exon 3 (c.356dupC; p.Ile120AspfsX42). Both wild-type PAI-1 (42.7 kDa) and mutated (Mut) PAI-1 (14.7kDa) were expressed in COS-1 cells, although the level of Mut PAI-1 expressed in the cell lysates was much lower. Wild-type PAI-1 was observed in the culture supernatant, whereas no Mut PAI-1 was detected in the supernatant.

CONCLUSIONS

 Considering the results of the present study, the translation of mouse studies to humans must be performed with great care.

Factor XIII subunits in human tears; their highly elevated levels following penetrating keratoplasty

BACKGROUND

As blood coagulation factor XIII (FXIII) is of high importance in wound healing, we determined the concentrations of FXIII A and B subunits (FXIII-A and FXIII-B) and their complex (FXIII-A(2)B(2)) in normal tears and in tears from patients undergoing penetrating keratoplasty (PKP).

METHODS

FXIII complex and subunit concentrations were measured by highly sensitive chemiluminescent ELISAs in tears from 60 healthy volunteers and from 31 patients undergoing corneal transplantation.

RESULTS

In non-stimulated tears from healthy volunteers, low but consistent amounts of FXIII-A and FXIII-B (medians: 2.13 μg/L and 7.22 μg/L, respectively) were measured, mostly in non-complexed form. Following stimulation of tear secretion FXIII levels moderately decreased, but if normalized to protein concentration they did not change. One day after PKP FXIII levels became highly elevated, then gradually decreased, but even on day 7 significantly exceeded pre-surgery values. The elevation of tear FXIII levels was significantly higher in PKP patients who later developed neovascularization of donor cornea.

CONCLUSIONS

FXIII subunits are low concentration components of normal tear. The striking elevation of FXIII subunit and FXIII-A(2)B(2) concentrations after PKP suggests the involvement of FXIII in corneal wound healing. Perioperatively measured high FXIII levels in tears seem to represent a risk of neovascularization.