Limited prognostic value of a staging system for twin-to-twin transfusion syndrome.

OBJECTIVE: Severe twin-to-twin transfusion syndrome (TTTS) is usually classified according to a staging system (I-V) based on ultrasonographic findings of polyhydramnios in the recipient, oligohydramnios in the donor, the presence or absence of the donor's bladder, Doppler waveform changes and (impending) hydrops. Stage correlates with the severity of disease, and it is assumed that, without intervention, severe TTTS will evolve in succession from stage I to stage V (fetal demise). However, this progression has not been validated in longitudinal studies. Herein, we report on the natural progression of severe TTTS in a cohort of patients from a regional Fetal Treatment Program. METHODS: Eighteen patients with severe TTTS, diagnosed between 15 and 25 weeks of gestation, were managed over a 28-month period. Data were collected until delivery, endoscopic surgical intervention or dual fetal demise. Patients were evaluated at least once a week. Stage, estimated fetal weight, percent recipient/donor body weight discordance and survival were recorded. RESULTS: The present study represents a total follow-up of 108 patient-weeks. Of 90 week-to-week evaluations, 65 showed no change in stage; 11 showed downstaging (by more than 1 stage in 3, or 27%), and 13 showed upstaging (by more than 1 stage in 8, or 62%). Nine patients (all stage II or above) underwent endoscopic laser ablation. Overall survival was 67%, and survival of at least 1 twin occurred in 78% of pregnancies. Weight discordance between the donor and recipient did not predict outcome. CONCLUSION: The current staging system for severe TTTS may not be helpful in predicting the direction, degree or speed of progression of the condition. Indications for intervention should remain stage-related, and not based on projected progression.

Corticotropin-releasing hormone and its structurally related urocortin are synthesized and secreted by human mast cells.

Stress activates the hypothalamic-pituitary-adrenal axis through CRH, leading to production of glucocorticoids that down-regulate immune responses. However, acute stress also has proinflammatory effects. We previously showed that restraint stress, as well as CRH and its structurally related urocortin (Ucn), could activate mast cells and trigger mast cell-dependent vascular permeability. Here we show for the first time that human cord blood-derived cultured mast cells (hCBMC) at 10 wk, but not at 2 wk, are immunocytochemically positive for CRH and Ucn; human leukemic mast cells are weakly positive for both peptides. The ability of these mast cells to synthesize CRH and Ucn was confirmed by showing mRNA expression with RT-PCR. hCBMC (8-14 wk) synthesize and store 1-10 ng/106 cells (10-20 microg/g) of both CRH and Ucn detected by ELISA of cell homogenates. Stimulation of IgE-sensitized hCBMC with anti-IgE results in secretion of most CRH and Ucn. These findings indicate that mast cells are not only the target, but also a potential source of CRH and Ucn that could have both autocrine and paracrine functions, especially in allergic inflammatory disorders exacerbated by stress.

Azelastine inhibits secretion of IL-6, TNF-alpha and IL-8 as well as NF-kappaB activation and intracellular calcium ion levels in normal human mast cells.

BACKGROUND: Mast cells are involved in allergic inflammation by secreting histamine, proteases and several cytokines, including interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and IL-8. Certain histamine-1 receptor antagonists, such as azelastine present in the ophthalmic solution Optivar, have been reported to inhibit histamine and tryptase secretion, but its effect on inflammatory cytokine release from normal human umbilical cord blood-derived cultured mast cells (hCBMC) are not well known. METHODS: We investigated the effect of azelastine on the secretion of IL-6, TNF-alpha and IL-8 from hCBMC, as well as its possible mechanism of action. hCBMC sensitized with IgE were pretreated for 5 min with azelastine at 0.01, 0.1, 1, 3, 6, 12, 24, or 60 microM of Optivar, before stimulation with anti-IgE for 6 h. Optivar vehicle without azelastine was used as control. Cytokines were measured by ELISA, intracellular calcium levels by calcium indicators confocal, and nuclear factor-kappaB (NF-kappaB) by electromobility shift assay. RESULTS: Stimulation with anti-IgE led to substantial secretion of IL-6, TNF-alpha and IL-8. Preincubation for 5 min resulted in almost maximal inhibition with 6 microM azelastine for TNF-alpha (80%), with 24 microM for IL-6 (83%) and 60 microM for IL-8 (99%); the vehicle solution at the same concentrations as Optivar had no effect. Stimulation with anti-IgE increased intracellular Ca2+ level and induced NF-kappaB expression in hCBMC, which was inhibited by 24 microM azelastine. CONCLUSION: Azelastine inhibited hCBMC secretion of IL-6, TNF-alpha and IL-8, possibly by inhibiting intracellular Ca2+ ions and NF-kappaB activation. Azelastine may, therefore, be helpful in treating allergic inflammation.

IL-1 induces vesicular secretion of IL-6 without degranulation from human mast cells.

Fc epsilon RI cross-linkage in mast cells results in release of granule-associated mediators, such as histamine and proteases, as well as the production of numerous cytokines, including IL-6. Mast cells have been increasingly implicated in inflammatory processes where explosive degranulation is not commonly observed. Here, we show that IL-1 stimulates secretion of IL-6 without release of the granule-associated protease tryptase in normal human umbilical cord blood-derived mast cells (hCBMCs). IL-6 secretion stimulated by IL-1 in hCBMCs is potentiated by priming with IL-4 and reflects the higher levels of IL-6 secreted from human leukemic mast cell line (HMC-1). Stimulating HMC-1 cells by both IL-1 and TNF-alpha results in synergistic secretion of IL-6. IL-6 is de novo synthesized, as its secretion is blocked by inhibitors of transcription or protein synthesis. IL-1 does not increase intracellular calcium ion levels in either hCBMCs or HMC-1 cells, and IL-6 stimulation proceeds in the absence of extracellular calcium ions. Ultrastructural Immunogold localization shows that IL-6 is excluded from the secretory granules and is compartmentalized in 40- to 80-nm vesicular structures. Selective secretion of IL-6 from mast cells appears distinct from degranulation and may contribute to the development of inflammation, where the importance of IL-6 has been recognized.

High levels of intrauterine corticotropin-releasing hormone, urocortin, tryptase, and interleukin-8 in spontaneous abortions.

Stress induces CRH secretion that activates hypothalamic-pituitary-adrenal axis and is also abortogenic. In addition to hypothalamus, CRH and its analog urocortin (Ucn) are also secreted locally outside the brain where they activate mast cells leading to inflammation; however, the level of CRH and Ucn or mast cell mediators has not been examined in products of conception (POC). CRH and Ucn were measured by enzyme immunoassay, tryptase by fluoroenzyme immunoassay, and IL-8 by ELISA in POC of 7-9 wk gestation from Caucasian women; they were divided into group I with elective abortions (n = 4), group II with one spontaneous abortion (n = 12), and group III with at least two spontaneous abortions (n = 7). CRH, Ucn, tryptase, and IL-8 levels were higher (P < 0.05) in group III (8683 +/- 1201 pg/g, 7961 +/- 1499 pg/g, 1553 +/- 572 ng/g, and 8317 +/- 1874 pg/g, respectively) than group II (2561 +/- 314 pg/g, 2349 +/- 394 pg/g, 403 +/- 97 ng/g, and 3199 +/- 449 pg/g, respectively) and group I (163 +/- 162 pg/g, 328 +/- 327 pg/g, 72 +/- 31 ng/g, and 3681 +/- 931 pg/g, respectively). Immunostaining of POC showed significantly more tryptase in group III women. High POC levels of CRH and Ucn under stress in habitual spontaneous abortions may activate uterine mast cells to secrete abortogenic tryptase and IL-8.