Nurse cells

Woodruff, R. I., Miller, A. L., and Jaffe, L. F. (1991). Difference in free calcium concentration between oocytes and nurse cells revealed by corrected aequorin luminescence. Biol. Bull. 181 349-350. 

Nasmyth A lot of the original asymmetry of the embryo is historical. The nurse cells are concentrated on one side. This is not dissimilar from epithelial delamination you start off with asymmetry there. 

It has been known for some time that T. spiralis antigens localize to Nurse cell nuclei (Ooi and Kamiya, 1986 Despommier et al., 1990 Sanmartin et al, 1991) and recently it has been shown that some of these antigens bear Tyv (Yao et al., 1998). It has been proposed that these... 

Ooi, H.K. and Kamiya, M. (1986) Antibodies to nurse cell and various stages of TrichineUa spiralis in patient sera. Japanese Journal of Parasitology 35,109-113. 

Capo, V.A., Despommier, D.D. and Polvere, R.I. (1998) Trichinella spiralis vascular endothelial growth factor is up-regulated within the nurse cell during the early phase of its formation. Journal of Parasitology 84, 209-214. 

Despommier, D., Symmans, W.F. and Dell, R. (1991) Changes in nurse cell nuclei during synchronous infection with Trichinella spiralis. Journal of Parasitology 77, 290-295. 

Lee, D.L., Ko, R.C., Yi, X.Y. and Yeung, M.H. (1991) Trichinella spiralis antigenic epitopes from the stichocytes detected in the hypertrophic nuclei and cytoplasm of the parasitized muscle fibre (nurse cell) of the host. Parasitology 102, 117-123. 

Polvere, R.I., Kabbash, C.A., Capo, V.A., Kadan, I. and Despommier, D.D. (1997) Trichinella spiralis synthesis of type IV and type VI collagen during nurse cell formation. Experimental Parasitology 86, 191-199. 

The anterior-posterior axis in Drosophila is defined at least in part by the products of the bicoid and nanos genes. The bicoid gene product is a major anterior morphogen, and the nanos gene product is a major posterior morphogen. The mRNA from the bicoid gene is synthesized by nurse cells and deposited in the unfertilized egg near its anterior pole. 

Development in Drosophila and other insects follows a somewhat different pathway, as is indicated in Fig. 32-6B. The egg, which is surrounded by follicle cells and 16 nurse cells, does not divide. However, its nucleus divides repeatedly, about once every nine minutes, to form -6000 nuclei. Only then do separating membranes form to give individual cells.9,285 316 317 During the first two hours the nuclei form a syncytium, in which they are embedded in a common cytoplasm, that allows free diffusion of signaling compounds. At first the nuclei are in the center, but later most migrate to the periphery and form a single layer of cells comparable to the blastoderm of amphibian cells. A few nuclei remain in the central cavity to become yolk cells, and some at the posterior pole become separated into pole cells. 

Experiments on the effects of autonomous and imposed electric fields in biomorphogenesis have been done on many systems including seaweed eggs, plant roots, nerve and muscle in culture, Cecropia oocyte-nurse cell cyncytae, amphibian and rodent limb regeneration and wound healing and regeneration in man (8, 28, 5k). It is clear from these experiments that a... 

Strong electric fields and currents have been measured in a number of multicellular systems ranging from Fucus at the two cell state, a Cecropia moth oocyte-nurse cell cyncytum, amphibianand rodent limbs in regeneration and man (8, 22, 28, 3) Thus it is imperative to develop a formulation of multicellular phenomena. 

J. Mucci, A. Hidalgo, E. Mocetti, P. F. Argibay, M. S. Leguizamon, and O. Campetella, Thymocyte depletion in Trypanosoma cruzi infection is mediated by frans-sialidase-induced apoptosis on nurse cells complex, Proc. Natl. Acad. Sci. USA, 99 (2002) 3896-3901. 

Immunofluorescent detection of TS protein was done with the use of monoclonal antibodies, developed by in vivo immunization of Balb/c mice with homogeneous recombinant rat hepatoma TS protein as an antigen. The specific anti-rat TS antibodies recognized also T. spiralis TS, as indicated by cross-reactivity on Western blot. Localization of the enzyme was based on analysis of pictures collected by confocal microscopy. Two types of T spiralis muscle larvae preparations were studied muscle larvae isolated from mouse muscles by a procedure destroying nurse cells and muscle larvae remaining in nurse cells, isolated as an intact nurse cell preparation. 

Intact nurse cells were obtained from the diaphragms of mice infected with T. spiralis, excised at day 30 postinfection. Nurse cells were isolated by restricted digestion (its progress controlled under binocular), by 1% trypsine in PBS buffer containing 0.02% EDTA. Digestion was stopped by washing with PBS containing Ca " " and Mg " " ions. 

Preparation of T. spiralis Specimens for Immuno-Localization Studies of Premature and Mature Muscle Larvae and Intact Nurse Cells This procedure was adapted from that used for C. elegans (Miller and Shakes 1995). 

Fixation of larvae, adult worms or intact nurse cells, suspensed in cold PBS, was done by adding cold x2 Ruvkun fixation buffer, diluted with 2% formaldehyde to xl final concentration. Frozen samples were stored at -80°C. After thawing. 

Photobleaching of T. spiralis preparations was performed, as the worms, as well as cytoplasm of nurse cells, emit a strong autofluorescence. In order to reduce it, the corresponding samples, protected against UV, were exposed to solar radiation for over 2 weeks. The process was monitored by confocal microscopy. 

Localization of thymidylate synthase protein was followed in selected T. spiralis developmental forms, including (i) juvenile muscle larvae, (ii) infective muscle larvae (isolated either alone or in the intact nurse cell complex), (iii) adult worms and (iv) embryos developing within adult worms. 

In infective muscle larvae of both sexes, whether isolated alone or as an intact nurse cell-larva complex, strong fluorescence signals were observed. They were associated mainly with cells of gonad and uterus primordia, and stichocyte. Strong positive reactions were also observed in the stichocyte nuclei vicinity, as well as in the canalicular tree of stichocytes and in lumen of esophagus of adult worms (not shown). 

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