[Cord blood: from bench to bedside]. / Le sang de cordon: du laboratoire au lit du malade.

Since 1974, umbilical cord blood (CB) has been shown to contain haematopoietic stem cells similar to stem cells from the bone marrow. In 1988, E. Gluckman and her colleagues performed - successfully - the first familial CB transplantation and cured a 5 years old child suffering from Fanconi's anemia. Rapidly, CB banks were organised throughout in the world and thanks to this novel source of haematopoietic stem cells, we can now find a donor for 75 % of the patients requiring a "bone marrow" transplantation. The major benefit of CB as a source of hematopoietic stem cells is its easy access. CB also allows a more significant degree of HLA incompatibility and thus offers an opportunity of transplantation to ethnic minorities for whom no HLA identical donors are available. However, several studies have shown that the number of cells harvested in a CB was closely correlated with the engraftment post transplantation and today, a minimum of 3.7 x 10(7) mononucleated cells/kg is recommended. This required amount of cells is not always reached due to the small volume often harvested from a CB. Therefore, to apply CB transplantations to adults, different approaches are currently being investigated : coinfusion of haploidentical cells, mesenchymal cells, a second CB, or the addition of CB expanded ex-vivo. Among these approaches, double CB transplantation seems nowadays the most promising alternative and ongoing studies should soon inform us whether the duration of aplasia will be improved.

Circadian and seasonal variations of hematopoiesis in cord blood.

Cord blood hematopoietic progenitors undergo circadian and seasonal variations. The lowest values are obtained between 4:00 and 12:00, as well as between May and August. This represents the first observation of such rhythms before birth.

Ex vivo expansion of CD34 + CD38- cord blood cells.

CD34+ cord blood (CB) cells were expanded in stromal cell-free long-term culture (LTC), in the presence of various combinations of interleukin-3 (IL-3), stem cell factor (SCF), IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), and anti-transforming growth factor-beta (anti-TGF-beta) antibody. The progenitor cell expansion was evaluated by monitoring the increase of CD34+ and CD34 + CD38- cells over a period of 21 days. The expansion of immature (B1-CFC, HPP-CFC) and of more committed progenitors (CFU-GM, CFU-GEMM, BFU-E) was also evaluated in specific samples. Our results show that (a) CD34+ cell expansion is highly variable depending on the cord blood samples studied, (b) significant correlations between B1-CFC and CD34 + CD38- and between total CFU and CD34+ cell expansion are observed, (c) SCF in combination with IL-3 appears to expand cell subsets that continue to express their CD34 + CD38- phenotype and that generate both immature and committed progenitors, and (d) the addition of IL-6, GM-CSF, or anti-TGF-beta does not significantly improve these expansions.

Comparison of the coexpression of CD38, CD33 and HLA-DR antigens on CD34+ purified cells from human cord blood and bone marrow.

Human umbilical cord blood (UCB) cells are currently considered as a potential source of stem cells for transplantation. However, it remains unclear whether a single collection of UCB contains enough progenitors to allow a successful engraftment in adult patients. We were interested in the comparison of the frequency of primitive progenitors in UCB and in human bone marrow (BM). UCB and BM CD34+ cells were purified and compared for their coexpression of CD38, CD33 and HLA-DR. UCB and BM mononuclear fractions were enriched in CD34+ cells using the CEPRATE LC system (CellPro, Bothell, WA). Double-labeling analysis with a flow cytometer showed that 67.9 +/- 7.2% of UCB CD34+ cells are CD38-, while in BM only 10.9 +/- 4.9% of CD34+ are CD38- (p < 0.001). Moreover, our study indicated that a significantly higher percentage of UCB CD34+ is CD33- (97.1 +/- 1.2%) compared to BM (61.8 +/- 8.6%) (p = 0.013). The coexpression of CD34 with HLA-DR was not significantly different in UCB and in BM (respectively, 86.3 +/- 2.7% and 92.7 +/- 5.1%). On the other hand, in vitro assays showed that the number of multipotent (colony-forming units granulocyte-erythroid-macrophage-megakaryocyte [CFU-GEMM]), myeloid (colony-forming units granulocyte-macrophage [CFU-GM]) and erythroid (burst-forming units-erythroid [BFU-E]) progenitors is lower in the CD34+ population from UCB than from BM. In conclusion, in UCB, we have found a significantly higher percentage of CD34+ cells which lacked the expression of CD38 and CD33 antigens suggesting that UCB contains higher proportions of immature progenitor cells (CD34+CD38- and CD34+CD33-) than BM. It seems thus likely that fewer UCB CD34+ cells than BM CD34+ cells would be required for sustained engraftment following transplantation.

Modulation of human cord blood progenitor cell growth by recombinant human interleukin 3 (IL-3), IL-6, granulocyte-macrophage colony stimulating factor (GM-CSF) and stem cell factor (SCF) in serum-supplemented and serum-free medium.

UNLABELLED: We evaluated the growth of cord blood myeloid progenitors or colony forming units granulocyte-macrophage (CFU-GM) and their response to various recombinant growth factors or colony stimulating factors (CSFs): interleukin 3 (IL-3), IL-6, granulocyte-macrophage CSF (GM-CSF) and stem cell factor (SCF). Using classical stimulant (human placenta conditioned medium or HPCM), we observed a significantly higher day-14/day-7 CFU-GM ratio in CB than in bone marrow (BM). The association of IL-3, IL-6, GM-CSF and SCF induced significantly more CB day-14 CFU-GM than HPCM. This effect is significantly greater in CB than in bone marrow. Since fetal calf serum (FCS) is known to contain inhibitors, we have compared the ability of CSFs to induce CFU-GM formation in FCS-supplemented and FCS-free culture. In CB, using HPCM, we obtained significantly more CFU-GM in FCS-free medium than in FCS-supplemented medium. This difference was corrected by the addition of anti-transforming growth factor-beta (TGF-beta) neutralizing antibody. However, with the association of the four CSFs, no significant difference between FCS and FCS-free culture was observed. IN CONCLUSION: a) day-14/day-7 CFU-GM ratio was higher in CB than in BM indicating that CB CFU-GM are more primitive than BM CFU-GM; b) FCS can be successfully replaced by serum-free medium; c) FCS contains inhibitors of day-14 CFU-GM and among them TGF-beta; and d) the association IL-3, SCF, GM-CSF and IL-6 seems able to totally overcome the inhibitory effect of FCS.

Elective induction of labor conducted under lumbar epidural block. II. Labor induction by amniotomy and intravenous prostaglandin.

Labor was electively induced at term in 117 clinically normal nulliparae and parous women by combining low amniotomy with intravenous administration of prostaglandin F2 alpha (n = 64) or prostaglandin E2 (n = 53). Analgesia was obtained by continuous lumbar epidural block with bupivacaine. The procedure was very effective in producing vaginal delivery within 24 h after prostaglandin infusion (n = 115), but it was accompanied by an extremely high incidence of uterine hypertonus. Tentative explanations for the transient uterine hyperstimulation are a direct stimulatory effect of the local anesthetic on the contractility of the myometrial fiber and/or a temporarily higher amount of circulating oxytocic compound reaching the myometrium due to local vasodilatation as a result of sympathetic nerve blockade. In some cases uterine hypertonus was associated with slowing of the basal fetal heart rate and, when severe, with the appearance of late deceleration patterns and fetal acidosis. In other cases the fetal heart rate deceleration is explained by the toxic effect of bupivacaine on the myocard. Since both the myometrial hyperactivity and the FHR alterations were temporary, fetal biochemical parameters were unaffected at completion of the first stage of labor. Because with intravenous prostaglandin uterine hyperstimulation is more difficult to avoid and regional analgesia further increases the hazard of both hypertonus and fetal heart rate deceleration, the combined application of an intravenous prostaglandin and continuous epidural analgesia should not be introduced into obstetrical practice.

Elective induction of labor conducted under lumbar epidural block. I. Labor induction by amniotomy and intravenous oxytocin.

Epidural analgesia (bupivacaine) was administered during labor after amniotomy, in some cases supplemented by intravenous oxytocin. A higher incidence of transient uterine hypertonus was seen after blocking. Fetal heart rate changes mainly took the form of bradycardia (in association with uterine hypertonus). At birth, the maternal biochemical condition was characterized by a lower degree of metabolic acidosis, compared to normal unanesthetized controls. The fetuses displayed a slight degree of hypoxia and hypercapnia. The mechanisms underlying these modifications are discussed. Epidural blockade in combination with elective induction of labor, whether or not supplemented by intravenous oxytocin, may carry a risk. Its magnitude is considered acceptable for both mother and fetus provided they are constantly under close surveillance, limited amounts of bupivacaine are administered and the second stage of labor is kept short. However, some warnings against epidural analgesia apply to patients with placental insufficiency and very active labor.

PIP: The maternal and neonatal influences of continuous lumbar epidural analgesia (CLEA; bupivacaine) administered during labor after amniotomy were studied. Intravenous oxytocin supplementation was employed in some cases. Analgesic blockade increased the incidence of transient uterine hypertonus. Fetal heart rate changes, primarily bradycardia, were associated with uterine hypertonus. At birth, a lower degree of maternal metabolic acidosis was observed in comparison with normal unanesthetized controls. A slight degree of hypoxia and hypercapnia was observed in the fetuses. Possible explanations for these changes are discussed. The application of CLEA in the elective induction of labor, whether accompanied by intravenous oxytocin or not, may have risks, though these are probably acceptable for the mother and fetus if they are closely observed, the amounts of bupivacaine administered are limited, and if the duration of the 2nd stage of labor is kept to a minimum. However, epidural analgesia poses greater risks to patients with placental insufficiency and very active labor.

Uterine contractility in spontaneous and induced labour.

Contractility parameters (uterine activity, contraction interval, amplitude, and frequency of contractions) were analyzed quantitatively during the active phase of first-stage of labour in 60 clinically normal term nulliparae with spontaneous or induced labour. Inductions were surgical (amniotomy alone) or by amniotomy combined with either intravenous oxytocin or prostaglandin administered intravenously (PGF 2alpha or PGE 2) or orally (PGE 2).

[Use of prostaglandins for termination of pregnancy in case of hydatidiform mole, missed abortion and anencephaly]. / Het gebruik van prostaglandinen voor het termineren van de "zwangerschap" in geval van mola hydatidose, afgestorven vrucht en anencephalie.

PIP: 2 prostaglandin (PG) compounds, PGF2 alpha and PGE2, were used to induce abortion in 24 women. 6 women with hydatidiform moles underwent i.v. or extra-ovular PG treatment, with an average induction-abortion interval (i.a.i.) of 8.5 hours. 3 women, 21-30 weeks pregnant, underwent abortion because of fetal anencephaly. They were given 1-3 doses of PGs intraamnially, supplemented with a few hours of i.v. ocytocin treatment, with an average i.a.i. of 49 hours and 53 minutes. 10 cases of missed abortion were treated mainly by intraamnial PG instillation, with an average i.a.i. of 18.5 hours. 5 cases of intrauterine death were treated with i.v. administration of PGs with an average i.a.i. of 12 hours and 42 minutes. Vomiting, nausea, and diarrhea were the most commonly reported side effects. No cervical injuries were reported.^ieng

Induction of labour with prostaglandin E2 tablets.

PIP: This study evaluates the efficacy and safety of PGE2 (prostaglandin E2) tablets for induction of labor in term pregnancy (38 to 42 weeks). 47 women (21 nullipara and 26 multiparae; ages 19 to 29 for nulliparae and 21 to 39 for multiparae) were studied; all were clinically normal according to the criteria of Thiery et al (1971), had intact membranes and mean Bishop scores (Bishop, 1964) of 7 for the nulliparae and 6.6 for the multiparae. In the parous group, the number of previous births ranged from 1 to 5. An initial dose of 0.5 mg PGE2 (1 tablet) was given to all except 1 patient who was given a 0.25 mg PGE2 as a test dose. A second dose of PGE2 was given if after 60 minutes, the recorded myometrial activity was less than 150 Montevideo Units. Subsequent doses of PGE2 (0.5 to 2.0 mg) were given at approximately 2-hourly intervals. Fetal scalp blood sample was collected at full cervical dilatation. 31 patients had spontaneous delivery while 16 patients (11 nulliparae and 5 multiparae) had to have vacuum extraction. The infants were assessed biochemically and clinically by Apgar scores at 1 and 5 minutes. Induction was successful in all except in a 23-year old obese nulliparous female at 40 weeks gestation who had a Bishop score of 5. This patient was given oxytocin infusion 27 hours after the first dose of PGE2; the baby was born following an easy vacuum extraction. Maternal morbidity included 1 to 3 episodes of vomiting in 8 of 21 nulliparae and 3 of 26 parous patients; elevated blood pressure during labor in 2 normotensive parous patients; postpartum hemorrhage which was easily controlled in 1 nullipara; and retained placenta in 1. Test dose to delivery interval ranged from 2 hours and 37 minutes to 18 hours and 29 minutes for the nulliparae and from 1 hour and 57 minutes to 9 hours and 13 minutes for the parous patients. The infants were in satisfactory condition at birth.^ieng