Mesenchymal stromal cells for treatment of steroid-refractory GvHD: a review of the literature and two pediatric cases

Severe acute graft versus host disease (GvHD) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation. Human mesenchymal stromal cells (MSCs) play an important role in endogenous tissue repair and possess strong immune-modulatory properties making them a promising tool for the treatment of steroid-refractory GvHD. To date, a few reports exist on the use of MSCs in treatment of GvHD in children indicating that children tend to respond better than adults, albeit with heterogeneous results.

We here present a review of the literature and the clinical course of two instructive pediatric patients with acute steroid-refractory GvHD after haploidentical stem cell transplantation, which exemplify the beneficial effects of third-party transplanted MSCs in treatment of acute steroid-refractory GvHD. Moreover, we provide a meta-analysis of clinical studies addressing the outcome of patients with steroid-refractory GvHD and treatment with MSCs in adults and in children (n = 183; 122 adults, 61 children). Our meta-analysis demonstrates that the overall response-rate is high (73.8%) and confirms, for the first time, that children indeed respond better to treatment of GvHD with MSCs than adults (complete response 57.4% vs. 45.1%, respectively).

These data emphasize the significance of this therapeutic approach especially in children and indicate that future prospective studies are needed to assess the reasons for the observed differential response-rates in pediatric and adult patients.

Nucleated red blood cells in cord blood of singleton term and post-term neonates

OBJECTIVE

This study aims to determine if nucleated red blood cells are elevated in pregnancies that continue beyond 289 days of gestation.

STUDY DESIGN

Cord blood was prospectively collected from term and post-term singleton gestations from August 1 to December 31, 1998. Umbilical artery nucleated red blood cells were counted per 100 white blood cells. The comparison was made between pregnancies ending at 261-289 days (37.1-41.2 weeks) of gestation and those ending after 289 days (> or = 41.3 weeks) of gestation.

RESULTS

Cord blood from 304 cases was obtained and evaluated for nucleated red blood cells per 100 white blood cells. The mean value of nucleated red blood cells per 100 white blood cells in the post-term neonate group was significantly higher than in the term neonate group (median 6.5, range 0-24 vs. median 3.7, range 0-14; p < 0.05). The values did not vary by fetal presentation, mode or duration of delivery. Neonatal outcome was comparable between both study groups.

CONCLUSION

In post-term gestation after 289 days nucleated red blood cells in cord blood are significantly increased. These results point towards a different fetal oxygenation in post-term pregnancies beyond 289 days of gestation and support the current practice of very close testing of fetal well-being under those circumstances.

Maternal and neonatal outcome of twin pregnancies complicated by single fetal death

OBJECTIVE

To study the maternal and neonatal outcome of twin pregnancies complicated by the intrauterine death of one fetus after 20 weeks of gestation.

DESIGN

Retrospective, observational study of 7 twin pregnancies out of 185 twin pregnancies with the diagnosis of a single intrauterine death over a 5-years period in a university hospital.

RESULTS

The incidence of single fetal death in twin gestation after 20 weeks was 3.8% in the study population with a high incidence of intrauterine growth retardation (IUGR) of the remaining fetus and preeclampsia in the further course of pregnancy. The incidence of preterm delivery was 71% with a mean gestational age of 33.0 +/- 1.0 weeks. The median interval from diagnosis of single fetal death to delivery was 10.2 +/- 4.1 days (range 1-28 days). 5 of 7 (71%) cases were delivered by cesarean section for standard obstetrical reasons. Neither perinatal nor neonatal death of the remaining twin were observed. Two cases of neurologic injury were diagnosed after delivery by ultrasound and MRI. No maternal coagulopathy related to single fetal death occurred.

CONCLUSION

Expectant management of single fetal death in twin pregnancies might be advisible under close surveillance of both, mother and the surviving fetus.

[Discolored amniotic fluid--results of prenatal diagnosis and clinical significance]

7000 pregnancies were analysed after genetic amniocentesis in respect of the further course and results of prenatal diagnosis (observation period 1975-1988). In 3.1% (217 cases) samples of amniotic fluid were discoloured. Vaginal haemorrhages prior to amniocentesis were recorded with significantly higher incidence (18%) in patients with discoloured amniotic fluid than in a control group (n = 217) with normal colour of the amniotic fluid (4.6%) (p less than 0.001). Miscarriages and chromosome anomalies occurred more often in the study group (3.7%/2.8%, control group: 0.9%/1.8%, n.s.). The risk of miscarriages was increased in cases with sanguineous amniotic fluid if the amniotic fluid alpha-fetoprotein values were enhanced at the same time. Significant differences were observed in respect of the incidence of foetal malformations in patients with discoloured amniotic fluid (7.8%) and in the control group (2.3%) (p less than 0.01). Borderline or definitely pathological amniotic fluid AFP concentrations were found often if the amniotic fluid was discoloured (6.9%, control group 3.2%). If discoloured amniotic fluid was sampled, foetal malformations should be excluded sonographically. In 82% of all cases with discoloured amniotic fluid and foetal malformations pathological sonographic findings and/or enhanced MS-AFP values were recorded even prior to amniocentesis.

[Vascular abnormalities of the umbilical cord--incidence, significance and possibility for prenatal ultrasonic detection]

Vascular anomalies of the umbilical cord are amongst the most frequent congenital malformations, their incidence being 0.2% to 1.4%. As a result of the latter the risk of occurrence of other malformations and chromosomal anomalies is markedly elevated. Between January 1977 and July 1987 a total of 78 cases (0.51%) of umbilical cord vascular anomalies were recorded at the Department of Gynaecology of the University of Heidelberg. Malformations occurred in 37% of the foetuses involved. 28% showed retarded growth and 9% had an abnormal set of chromosomes. Anomalies of the urinary tract and malformations of the thoracic organs were very frequent. Total mortality after the 28th pregnancy was about 14%. Currently available high-resolution real-time ultrasound equipment can show up even prenatally pathological variations of the umbilical vascular pedicle (e.g. a single umbilical artery). Because of the manifold risk involved, routine ultrasound control is recommended. If this anomaly is diagnosed, the pregnancy should be classified and treated immediately as a high-risk pregnancy.

Instabilities in a continuous medium model for the retina

The shape of the spatial response of the retina on a small light stimulus as found by Rodieck (1965) for the cat, and proposed for the human retina among others by Korn and von Seelen (1972), resembles a Mexican hat known as a sombrero. A model presented by Röhler (1976), using a continuous medium as a description of the retina, can lead to such a "Mexican hat" response function for a specific choice of parameters. The spatial Fourier transform of this response function has a general appearance that corresponds to that calculated for stationary signals. However, such an analysis of the model for stationary signals is incomplete. Inspection of the time-dependent equations shows that it is unstable precisely for those parameter values that give the stationary response function its desired shape. Such stationary situations cannot be physically realized since the model is unstable.