Characterization of endothelial-like cells derived from human mesenchymal stem cells

BACKGROUND

Blood-derived endothelial progenitor cells (EPC) have been used to treat ischemic disease. However, the number of EPC that can be obtained from adult blood is limited.

OBJECTIVE

To characterize endothelial-like cells obtained from human bone marrow and determine their ability to stimulate new blood vessel formation in vivo.

METHODS

Mononuclear cells (MNC) were isolated from human bone marrow or umbilical cord blood and cultured in endothelial growth medium (EGM-2). Mesenchymal stem cells (MSC) were isolated from bone marrow and induced to differentiate into endothelial-like cells (MSCE), or adipocytes or osteocytes by growth in EGM-2, adipogenic or osteogenic medium.

RESULTS

Cells obtained by culturing bone marrow MNC in EGM-2 formed cord- or tube-like structures when grown on Matrigel(TM) and expressed several endothelial marker proteins. However, cell morphology and the profile of endothelial marker protein expression were different from those of cord blood-derived EPC (cbEPC). Cells with a similar phenotype were obtained by differentiation of MSC into MSCE, which was accompanied by an increase of endothelial marker proteins and a diminished capacity to differentiate into adipocytes. Subcutaneous implantation of MSCE in collagen plugs in non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice resulted in formation of functional blood vessels that had incorporated the MSCE.

CONCLUSIONS

Our results show that MSCE and cbEPC are different cell types. The formation of functional blood vessels by MSCE, combined with high yields and a reduced capacity to differentiate into other cell types compared with MSC, makes these cells potentially useful for autologous therapy of ischemic disease.

Botulinum toxin injections combined with or without sodium hyaluronate in the absence of electromyography for the treatment of infantile esotropia: a pilot study

OBJECTIVE

To evaluate the feasibility and safety of a revised technique of botulinum toxin type A (BTA) injections for the treatment of infantile esotropia.

METHODS

Forty-seven patients with infantile esotropia were randomly divided into two groups. In group A, 23 cases were treated with a bilateral injection of 2.5-3.75 U BTA combined with sodium hyaluronate (SH) to the medial rectus muscle. In group B, 24 cases were treated with a bilateral injection of 2.5-3.75 U BTA solution alone to the medial rectus muscle. Electromyography was not used in the study. All patients received one injection and were evaluated 2 weeks, 3 months, and 6 months following injection.

RESULTS

The measured changes between groups A and B included the frequencies of good alignment 6 months after injections (30.4% vs 37.5%), complicated ptosis (2.2% vs 20.8%), and vertical deviation (2.2% vs 2.1%).

CONCLUSION

BTA injections combined with or without SH in the absence of electromyography demonstrated effectiveness and feasibility in the treatment of infantile esotropia. A relative decrease in the frequency of complicated ptosis resulted from injections of BTA+SH.

Treatment of fulminant liver failure by transplantation of microencapsulated primary or immortalized xenogeneic hepatocytes

BACKGROUND

The aim of this study was to evaluate the in vitro and in vivo function of hepatocytes after immortalization, cryopreservation, encapsulation, and xenotransplantation into mice with fulminant liver failure (FLF).

METHODS

Rat and human hepatocytes were isolated by collagenase digestion. Human hepatocytes were immortalized using lentiviral vectors. Rat and immortalized human hepatocytes (IHH) were encapsulated in 400 microm of alginate-poly-L-lysine (PLL; Sigma, Buchs, Switzerland)-alginate membranes and cryopreserved using a computerized device. In vitro, encapsulated hepatocytes (cryopreserved or noncryopreserved) were cultured; albumin secretion was measured by enzyme-linked immunosorbent assay. Microencapsulated (cryopreserved or noncryopreserved) hepatocytes were transplanted intraperitoneally to mice with FLF: group 1 (n = 10) transplantation of empty capsules; group 2 (n = 12) transplantation of free primary rat hepatocytes; group 3 (n = 12) transplantation of cryopreserved encapsulated rat hepatocytes; group 4 (n = 10) transplantation of encapsulated rat hepatocytes; group 5 (n = 9) transplantation of cryopreserved encapsulated IHH; group 6 (n = 10) transplantation of encapsulated IHH.

RESULTS

Compared with free primary hepatocytes, cryopreserved or noncryopreserved encapsulated rodent hepatocytes showed similar levels of continuous in vitro albumin secretion over 1 week. Cryopreserved or noncryopreserved encapsulated IHH showed minimal albumin secretion compared with free primary human hepatocytes. Fulminant liver failure, produced by a combination of acetaminophen and 30% hepatectomy, resulted in a 20% to 30% host survival. In groups 1 and 2, survival was unmodified, compared with untreated mice. For groups 3 and 4, transplantation of cryopreserved or noncryopreserved encapsulated rat hepatocytes significantly increased survival rates to 66% and 80%, respectively (P < .01). For groups 5 and 6, transplantation of cryopreserved or noncryopreserved encapsulated IHH improved host survival to 50% and 55%, respectively (P < .05).

CONCLUSIONS

Primary rodent hepatocytes maintained synthetic functions after encapsulation and cryopreservation. Immortalized human hepatocytes showed minimal albumin secretion in the absence of encapsulation and cryopreservation, suggesting that hepatocytes lose some specific functions after immortalization. After induction of FLF in mice, intraperitoneal transplantation of encapsulated (primary or immortalized, cryopreserved or noncryopreserved) xenogeneic hepatocytes significantly improved survival. These results indicate that naive and genetically modified hepatocytes can be successfully encapsulated, stored by cryopreservation, and transplanted into xenogeneic recipients with FLF to sustain liver metabolic functions.

Assessment of 18F-FDG-Leukocyte Imaging to Monitor Rejection After Pancreatic Islet Transplantation

AIM

We sought to investigate the feasibility of 18F-FDG-leukocyte imaging to detect islet rejection.

METHODS

Two thousand Sprague-Dawley (SD, syngeneic group) or Lewis (allogeneic group) islet equivalents were intraportally injected into SD rat recipients. Four and 7 days after transplantation, 10(8) 18F-FDG-labeled splenocytes were injected into the jugular vein. Splenocytes were harvested from naïve or sensitized (12 days after intraportal transplantation of 2000 Lewis IEQ) SD rats. Positron emission tomography (PET) imaging was started 5 minutes after splenocyte infusion and performed hourly for 4 hours.

RESULTS

One hour after splenocyte injection, FDG was mainly detected in the heart and lungs. It was then further distributed to other organs, and from the second hour, the highest tracer concentration was located in the abdomen. Liver FDG uptake was similar between syngeneic, allogeneic, and sensitized allogeneic groups at 4 and 7 days after islet transplantation.

DISCUSSION

No islet rejection was detected by 18F-FDG-leukocyte imaging. The amount of transplanted tissue was only few millilitres and the additional related inflammation in case of rejection is small and difficult to detect. The liver showed a relatively high spontaneous tracer uptake; the related background prevented detection of a potential increase in tracer uptake in cases of islet rejection.

Epidemiologic features of enterovirus associated with hand, foot and mouth disease in 2013 and 2014 in Shenzhen, China

Hand, foot and mouth disease (HFMD) is responsible for a heavy economic and social burden in the Asia-Pacific region. Previous studies have shown that coxsackievirus A6 (CVA6) and coxsackievirus A10 (CVA10) have become the predominant agents of HFMD in mainland China in recent years, replacing enterovirus 71 (EV71) and coxsackievirus A16 (CVA16), although it is unclear if this is consistent throughout China. In this study, samples from 253 HFMD cases were collected in Shenzhen, China, from May 2013 through April 2014 to identify the etiological agent of HFMD. In total, 64.8% (164/253) of HFMD cases were enterovirus positive, in which 81.1% (133/164) were determined to be CVA6. The phylogenetic tree of the partial viral protein 1 sequence showed that the CVA6 isolates were divided into four clusters (Clusters A to D), and cluster D was further divided into four sub-clusters (Clusters D1 to D4). The 133 CVA6 samples isolated in our study were classified into cluster D4, in which the first identified sequence was isolated in Shenzhen in 2008. This study demonstrated that the CVA6 cluster D4, which is predominantly circulating in HFMD in mainland China, may have originated from a local strain identified in 2008 in Shenzhen.

Evaluation of POSSUM in predicting post-operative morbidity in patients undergoing pancreaticoduodenectomy

The Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM) is a predictive scoring system for post-operative morbidity. The present study assessed the value of POSSUM in predicting post-operative morbidity following pancreaticoduodenectomy (PD). POSSUM scores were prospectively calculated for 265 consecutive cases of PD performed between 2005 and 2007. Expected morbidity was estimated based on POSSUM scores and was compared with observed morbidity. Patients were also stratified into one of four groups based on their individual POSSUM scores and subsequent risk of morbidity. Mean expected morbidity was 43.81% (116 cases) and mean observed morbidity was 39.62% (105 cases) (no statistically significant difference). It is concluded that the POSSUM scoring system has high value for predicting the risk of morbidity in PD patients.

Multidisciplinary approach to palliation of obstructive jaundice caused by a central hepatocellular carcinoma

BACKGROUND/AIMS

Obstructive jaundice due to intraductal tumour growth is a rare symptom in association with hepatocellular carcinoma (HCC).

METHODS

We report a 65-year-old white male who was admitted to our department with a 2-week history of progressive jaundice. At laparotomy, the liver showed advanced cirrhosis due to long-standing biliary obstruction. Cholangiography confirmed total obstruction of the main bifurcation of the hepatic duct by intraductal tumour growth. Combination treatment with surgical segment III drainage, transcatheter arterial embolization and radioembolization with yttrium-90 resin particles and endoscopic stenting was performed. This form of treatment has never been reported before.

RESULTS

With these combined procedures, relief of jaundice and a survival time of 32 months could be achieved.

CONCLUSION

The combination of palliative methods may relieve jaundice, ensure a good quality of life and possibly prolong survival in patients with mechanical tumour obstruction of the biliary tree by HCC.

Anti-CD25 mAb, anti-IL2 mAb, and IL2 block tolerance induction through anti-CD154 mAb and rapamycin in xenogeneic islet transplantation

BACKGROUND

We have used anti-CD154 monoclonal antibody (mAb; MR1) and rapamycin (rapa) to induce tolerance to islet xenografts. The aim of this study was to investigate whether classical anergy and/or regulation by interleukin (IL)2-dependent CD25+ T regulatory cells played roles in the induction and maintenance of tolerance in this model.

METHODS

Streptozotocin-induced diabetic mice were transplanted with rat islets. We performed the following groups: control group, islet transplantation without therapy; rapamycin group, 0.2 mg/kg by oral gavage on days 0, 1, 2, and every other day to day 14; anti-CD154 mAb (MR1) group, 0.5 mg intraperitoneally on days 0, 2, and 4; combination therapy group with rapa and MR1. We then administered in addition to the combination therapy with early (from days 0 to 14 [for IL2] or to 28 [for anti-IL2 mAb and anti-CD25 mAb] post-transplantation) or late (from days 100 to 114 [for IL2] or to 128 [for anti-IL2 mAb and anti-CD25 mAb] posttransplantation) recombinant IL2 (2000 U, intraperitoneally twice a day), a neutralizing anti-IL2 mAb (S4B6-1, 0.3 mg intraperitoneally twice weekly), and a depleting anti-CD25 mAb (PC61, 0.3 mg intraperitoneally twice weekly), respectively. Histology was performed at time of rejection.

RESULTS

Rapa and MR1 therapy alone significantly prolonged xenograft survival compared to the control group: median graft survival was 34 days versus 17 days (P<.05) and 98 days versus 17 days (P<.05), respectively, but rejection still occurred. Combination therapy with MR1 and rapa allowed indefinite graft survival (median graft survival [MGS]>200 days, P<.001). When exogenous IL2 was administered early with MR1 and rapa, rapid rejection developed in 18 of 18 mice (MGS 7 days), whereas when IL2 was given late, only 3 of 10 developed rejection. Early administration of anti-IL2 mAb led to rejection in 10 of 10 mice (MGS 42 days), whereas late administration led to rejection in only one of four mice. Early administration of anti-CD25 mAb led to rejection in eight of nine mice (MGS 49 days), whereas late administration led to rejection in only three of seven mice.

CONCLUSIONS

Rapa and MR1 allowed indefinite graft survival of islet xenografts. Classical anergy and regulation by IL2-dependent CD25+ T regulatory cells were critical in the induction of tolerance in the immediate posttransplantation period and less important for maintenance of tolerance.

[Malformations of the human tail bud or: caudal agenesis syndrome. A review]

This study presents radiological and clinical findings in 70 patients with aplasia of caudal spinal segments and associated anomalies of the lower extremities and the inner organs. From a functional point of view 5 different types can be classified--unilateral hemi-aplasia, bilateral aplasia with or without sacral plateau, complex malformations of the caudal spine and medial spinal aplasia. Foot deformities and anomalies of the inner organs are common findings regardless to the extent of spinal aplasia, whereas popliteal webbing is only seen in cases with involvement of the lumbar spine. The lack of osseous junction between the spine and the pelvis leeds to a lumbopelvic kyphosis. Additionally the iliac wings are rotated in the frontal plane with the result of a narrow pelvic outlet and a change in the geometry of the hip joints. Embryologically all types of caudal spinal aplasia can be referred to a damage of the human tail bud. However, the term "Syndrome of Caudal Regression" is misleading; with respect to the presented results it is proposed to call this type of spinal malformation "Syndrome of Caudal Aplasia".

Phylogenetic disparity influences the predominance of direct over indirect pathway of antigen presentation in islet xenotransplantation

BACKGROUND

Cellular immunity plays a major role in rejection of xenografted islets. Depending on the phylogenetical disparity, direct or indirect antigen presentation is predominant. The aim of this study was to analyze in vitro the predominance of direct or indirect presentation, and in vivo the effect of macrophage depletion on concordant and discordant islet xenograft survival.

MATERIALS AND METHODS

In vitro, we performed mouse antirat and mouse antihuman mixed lymphocyte reactions (MLR) after depletion of responder or stimulator antigen-presenting cells. In vivo, streptozotocin-induced diabetic C57BL/6 mice were treated by gadolinium chloride to deplete macrophages and rat or human islets were transplanted under the kidney capsule. Islet function was followed by glycemia and xenografts were analyzed at regular intervals for histology.

RESULTS

Mouse antirat MLR showed a predominant direct antigen presentation pathway, whereas in mouse antihuman MLR, direct and indirect pathways were similarly involved. Survival of rat islets was not modified by GdCl therapy. In contrast, survival of human islets was significantly prolonged in GdCl-treated mice. Macrophage infiltration was decreased in concordant and discordant GdCl-treated xenografts at day 4, compared to controls. At day 15, macrophage infiltration was similar in all groups.

DISCUSSION

Our results indicate that direct antigen presentation is dominant in rejection of concordant islet xenografts and cannot be influenced by host macrophage depletion. Both direct and indirect antigen presentation are involved in rejection of discordant xenogeneic islets. Macrophage depletion or inhibition should be considered as therapeutic tool for discordant islet xenotransplantation.

A novel 4.9 Kb deletion at beta-globin gene is identified by the third-generation sequencing: case report from Baoan, China

BACKGROUND

Thalassemia is a common inherited haemoglobin disorder worldwide, several methods have been utilized in the step-wise screening. Even though hundreds of mutations in globin genes have been reported, novel mutations are continuously emerging as the development of DNA sequencing.

METHODS

The case is a 27-year-old female with abnormal values of routine hematological indices, who was admitted for genetic screening of thalassemia. Genomic DNA was extracted and used for genetic assays cover 26 mutations in HBA and HBB genes: gap-PCR and agarose gel electrophoresis were performed to detect deletions, while PCR-reverse dot blot was used to detect point mutations. The next- and third- generation sequencing were used to identify the known and potential novel genotypes of thalassemia, and multiplex ligation-dependent probe amplification (MLPA) was used for genotype validation.

RESULTS

Hematological results indicate microcytic hypochromic anemia, high HbA2 (7.2%) and high HbF (6.2%). None of the known genotypes of thalassemia were matched for this case, but a novel 4.9 Kb deletion at HBB gene (hg38, Chr11: 5226187-5231089) was discovered by the third-generation sequencing, the novel deletion was also validated by MLPA (8 probes, 11p15.4: 203314-207652).

CONCLUSIONS

This study suggests the third-generation sequencing has promising potentiality to discover novel genotypes (especially deletions) of thalassemia.

Role of CD40-CD154 pathway in the rejection of concordant and discordant xenogeneic islets

BACKGROUND

Costimulatory blockade has been shown to allow long-term survival of xenogeneic islets. The aim of the present study was to evaluate the role of recipient CD40 and CD154 in the rejection process of concordant and discordant islet xenotransplantation (Tx).

METHODS

Diabetic C57BL/6 mice, CD40- or CD154 knockout (KO) mice were transplanted with either concordant rat or discordant human islets.

EXPERIMENTAL DESIGN

group 1, control (ie, C57BL/6 mice received islet Tx without therapy); group 2, C57BL/6 mice received islet Tx with anti-CD154 monoclonal Ab (mAb) therapy; group 3, CD40 KO mice; and group 4, CD154 KO mice were used as recipients without therapy. Mouse anti-rat mixed lymphocyte reactions (MLR) were performed using mouse splenocytes obtained from animals transplanted with rat islets in groups 1 to 4.

RESULTS

In group 2, short-term anti-CD154 mAb therapy significantly prolonged rat-to-mouse and human-to-mouse xenograft survival, compared to controls. In CD40-KO and CD154-KO recipients, survival of concordant or discordant islets was not prolonged significantly compared to control groups. Mouse anti-donor rat cellular responses were reduced approximately 50% in group 2 but remained unmodified in groups 3 and 4, when compared to group 1.

CONCLUSIONS

Improved graft survival and reduced MLR responses against donor cells in vitro among the anti-CD154 mAb-treated mice could be explained by specific targeting of activated T cells with subsequent inactivation by anergy and/or elimination by apoptosis, or complement- or cellular-mediated mechanisms. Rejection of xenografts and strong MLR responses against donor cells in vitro in CD40 or CD154 KO animals is possible through efficient activation of alternate pathways of costimulation.

Retransplantation of discordant xenogeneic islets with costimulatory blockade

BACKGROUND

The aim of the study was to analyze the possibility of xenogeneic islet retransplantation using costimulatory blockade.

METHODS

Streptozotocin-induced diabetic mice were transplanted under the kidney capsule with human islets. Mice were nephrectomized and retransplanted with 1000 human islets under the contralateral kidney capsule 14 days later. Four groups were performed group I, first and second Tx without MR1; group II, first Tx without MR1, second Tx with MR1; group III, first Tx with MR1, second Tx without MR1; group IV, first and second Tx with MR1. A control group was transplanted only once without MR1 with human islets. After second Tx, cross-matches between recipient, serum and human lymphocyte were done for detection of antidonor antibodies.

RESULTS

In the control group, mean graft survival was 13 (+/-7) days. In group I, mean graft survival was 5 +/- 3 days. In group II, mean graft survival was 16 +/- 13 days. In group III, mean graft survival was 81 +/- 22 days. In group IV, no rejection were recorded and all graft survived more than 120 days. Pretransplant cross-matches were negative. In groups I and II all cross-matches were positive, while none were positive in group IV.

CONCLUSION

Retransplantation of xenogeneic islets was associated with accelerated rejection. After presensitization, MR1 was unable to induce tolerance to a second Tx. MR1 given at the first Tx only allowed prolonged survival of the second Tx, but rejection still occurred. MR1 given at first and second Tx allowed long-term survival of retransplanted xenoislets and prevented occurrence of antidonor antibodies.

[A case report of idiopathic polypoidal choroidal vasculopathy]

PURPOSE

To report a case of idiopathic polypoidal choroidal vasculopathy (IPCV) and its angiographic characteristics.

METHODS

General ophthalmic check up, analyses of fundus picture, funds fluorescein angiography (FFA), indocyanine green angiography (ICGA) as well as literature review.

RESULTS

The lack of typical choroidal neovascularization (CNV) on FFA and characteristic polypoidal choroidal vasculopathy on ICGA as well as its unsymmetrical manifestation and discrepancy with age-related macular degeneratio (AMD) on the fundus picture are typical signs for the diagnosis of IPCV.

CONCLUSION

The angiographic features on FFA and ICGA are specific for the diagnosis of IPCV. Differentiating IPCV and AMD has clinical significance in prognosing the visual acuity, progress and management of the diseases.

[Effect of levodopa on visual evoked potential in amblyopia]

PURPOSE

To evaluate the efficacy of levodpa treatment for amblyopia.

METHODS

The patients with amblyopin were given a single dose of levodopa, and the normal control group was established with the other normal eye in unilateral amblyopia. Their pattern visual evoked potential(PVEP) were tested before and after taking levodopa.

RESULTS

After taking a single dose of levodopa, the PVEP in the normal eyes showed that the N1P1 amplitudes evoked by middle spatial frequency stimuli and the P1N2 amplitudes evoked by high spatial frequency stimuli increased, however, in the amblyopic eyes showed that the N1 latency evoked by low spatial frequency stimuli and P1 latency evoked by middle spatial frequency decreased.

CONCLUSION

A single dose of levodopa administration can induce improvement of PVEP in the amblyopic eyes, and levodopa may be efficacious in the amblyopic therapy.

[Observation of compensatory head posture in superior oblique muscle paralysis]

PURPOSE

Superior oblique muscle paralysis is the most common disease in clinic. We analysed the cause, machanism and regularity of compensatory head posture in superior oblique muscle paralysis.

METHODS

All of 27 cases with superior oblique muscle paralysis aere examined regularly, and special muscle, binocular single vision function with synoptophore examined. Bielschowsky test was made.

RESULTS

In our cases, the incidence rate of compensatory head posture was 40.7%, which had relations with age when a patient had disease, period and function of binocular single vision.

CONCLUSION

The existance of binocular single vision function is the physiological bases leading to compensatory head posture, and the patients whose ages are older than 3 years and the course is less than 10 years may present the compensatory head posture. So we should pay attention to early diagnosis and training to restore the binocular single vision function.

Preservation and observation of anterior ciliary vessels in rectus muscles during strabismus surgery

PURPOSE

To observe the form and number of the anterior ciliary vessels (ACV) in rectus muscles. To train technician in preservation and observation of ACV, so preservation can be done in cases with a risk of anterior segment ischemia (ASI).

METHODS

Curved foreign knife, iris hook, plastic rubber band and standard operating loupes (3x.) or microscope were used in the surgery on 34 cases of comitant strabismus and 18 cases of paralytic strabismus.

RESULTS

The ACVs per muscle in medial, lateral, superior, inferior rectus were 3.08, 3.26, 3.50 and 3.50 respectively in 89 muscles of 52 surgical strabismus cases. All ACVs in 16 rectus muscles and 90 out of 220 ACVs in 73 rectus muscles were too small or too short to be dissected. The success rate of ACV preservation was 91.5% (119/130). 105 out of 130 vessels were saved using loupe magnification and 14 pit pf 130 vessels were saved under operating microscope.

CONCLUSIONS

The number of ACV in rectus muscles are more than 2 in our observation cases. The ACV preservation has the clinical value of allowing us to perform muscle surgery on three or more rectus muscles simultaneously and get final surgical results more earlier after ACV in each muscle are dissected and preserved otherwise staged surgery are needed. The each strabismus surgeon must know this technique.