• Applied Microscopy
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• 제12권1호
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• pp.49-56
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• 1982

전신성 Cryptococcosis로 판명된 4세 남아의 피부 생검조직에서 발견된C. neoformans의 미세구조를 광학현미경 관찰과 함께 보고 하였다. 광학현미경 관찰에서는 각종 만성 염증 세포의 침윤과 함께 다수의 구형의 organism을 관찰할 수 있었다. 전자현미경적으로도 난원형의 세포가 gelatinous 또는 filamentous한 capsular material에 둘러 싸여 단세포 혹은 여러개의 세포가 모여 있는 상태로 관찰되었으며 budding중인 상태의 것도 관찰되었다. 세포막은 고전사 밀도의 여러층으로 구성되어 있었으며 한개의 핵과 핵인이 관찰되었고 세포질내에는 mitochondria, ribosome, lipid bodies, vacuole등과 함께 plasma membrane의 infolding으로 형성된 mesosome-like structure도 관찰되었다.

• 한국어류학회지
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• 제19권4호
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• pp.286-291
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• 2007

칼납자루 Acheilognathus koreensis 정자의 미세구조를 전자현미경으로 관찰하였다. 칼납자루 정자의 미세구조는 잉어과 어류정자의 일반적인 구조와 같이 둥근 두부, 얕은 핵와, 세포의 측면에 위치한 편모구조 그리고 비 대칭적인 편모구조의 특징을 취하고 있었다. 그러나 중편에 위치한 미토콘드리아는 대부분의 잉어류에서와는 달리 융합되어 하나를 형성하고 있으며 그 주위를 막성 구조물들이 둘러싸고 있었다. 하나로 융합된 미토콘드리아를 가지는 정자의 구조는 여러개로 나타나는 것에 비하여 경골어류에서는 파생형질로 알려져 있다. 잉어류 정자에서 미토콘드리아가 융합되어 하나로 나타나는 구조는 Rodeus와 Puntungia에서 보고되어 있으며 그 주위를 막성구조물이 둘러싸고 있는 것은 납자루류에서만 보고되고 있다.

• Applied Microscopy
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• 제25권2호
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• pp.39-52
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• 1995

Pinealocytes in the lower vertebrate are known to have photoreceptive function. These photoreceptor cells have been characterized morphologically in various species of lower vertebrates. No such ultrastructural studies, however, were reported in fresh water turtle. The purpose of this study is to characterize the pinealocytes and the phylogenetic evoluton of these cells is discussed in terms of functional analogy. I. Light microscopy: The pineal body was divided into incomplete lobules by connective tissue septa containing blood vessels, and parenchymal cells were arranged as irregular cords or follicular pattern. In the lobules, glandular lumina were present and contained often densely stained materials. II. Electron microscopy: The pineal parenchyma had three categories of cells: photoreceptor cells, supportive cells and nerve cells. The photoreceptor cells had darker cytoplasm compared to the supportive cells, and the enlarged apical cytoplasm(inner segment) containing abundant mitochondria and dense cored vescles protruded into the glandular lumen in which lamellar membrane stacks(outer segment), dense membranous materials, and cilia were present. Some of these lamellated membrane stacks appeared to be dege-nerating while others were apparently newly formed. Constricted neck portion of the photoreceptor cells contained longitudinally arranged abundant microtubules. centrioles and cross-striated rootlets. Cell body had well developed Golgi apparatus, abundant mitochondria, dense granules($0.5{\sim}1{\mu}m$), dense cored vesicles($70{\sim}100nm$), and rough endoplasmic reticulum occasionally with dense material within its cisterna. Basal portion of the photoreceptor cells had basal processes often with synaptic ribbons, which terminate in the complicated zone of cellular and neuronal processes. Synatpic ribbons often made contact with the nerve processes and the cell processes of neighboring cells. In some instances, these ribbons were noted free within the basal process and were also present at the basal cell mem-brane facing the basal lamina. Obvious nerve endings with clear and dense cored vesicles were observed among the parenchymal cells. Photoreceptor cells of the snapping turtle pineal body were generally similar in fine structure to those of other lower verterbrates reported previously, and suggested to have both photoreceptive and secretory functions which were modulated by pinealofugal and pinealopedal nerves. The supportive cells were characterized by having large dense granules($0.3{\sim}1{\mu}m$), abundant ribosomes, well developed Golgi apparatus and rough endoplasmic reticulum. These cells were furnished with microvilli on the luminal cell surfaces, and often had centrioles, striated rootlets, abundant filaments especially around the nucleus, and scattered microtubules. Some supportive cells had cell body close to the lumen and extended a long process reaching to basal lamina, which appeared to be a glial cell. Nerve cells within the parenchyma were difficult to identify, but some large cells located basally were suspected to be nerve cells, since they had synaptic ribbon contact with photoreceptor cells.

• 한국축산식품학회지
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• 제37권5호
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• pp.654-662
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• 2017

Extracellular microvesicles are membranous nano-sized cellular organelles secreted by a variety of cells under normal and pathological conditions and heterogeneous in size ranging from 30 nm to $1{\mu}m$. They carry functional microRNAs that can influence immunity and development. For a particular application of microvesicles, choice of isolation method is particularly important; however, their isolation methods from colostrum in particular have not been described clearly. In this work, differential ultracentrifugation as a conventional method, ultracentrifugation with some modification such as additional precipitations, ultrafiltration, sucrose gradient separation and ExoQuick$^{TM}$ as a commercial reagent were compared. The goal was to compare mainly microvesicular total microRNA yield, distribution and purity among the methods then select the best isolation method for bovine colostrum microvesicles based largely on microRNA yield with the view of applying the vesicles in work where vesicular microRNA cargo is the target bioactive component. Highest yields for vesicular microRNA were obtained using conventional methods and among them, subsequent ultracentrifugation with 100,000 g and 135,000 g conventional method 2 was selected as it had the highest RNA to protein ratio indicating that it pelleted the least protein in relation to RNA an important factor for in vivo applications to assess microvesicle functionalities without risk of contaminating non-vesicular biomaterial. Microvesicles isolated using conventional method 2 were successfully internalized by cells in vitro showing their potential to deliver their cargo into cells in vitro and in vivo in case of functional studies.

• BMB Reports
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• 제51권8호
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• pp.406-411
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• 2018

Exosomes are small membranous vesicles which contain abundant RNA molecules, and are transferred from releasing cells to uptaking cells. MicroRNA (miRNA) is one of the transferred molecules affecting the adopted cells, including glioma cells. We hypothesized that mesenchymal stem cells (MSCs) can secrete exosomes loading miRNA and have important effects on the progress of gliomas. To determine these effects by treating exosomal miRNA in culture media of miRNA mimic transfected MSCs, we assessed the in vitro cell proliferation and invasion capabilities, and the expression level of relative proteins associated with cell apoptosis, growth and migration. For animal studies, the mice injected with U87 cells were exposed to exosomes derived from miRNA-584-5p transfected MSCs, to confirm the influence of exosomal miRNA on the progress of glioma. Based on our results, we propose a new targeted cancer therapy wherein exosomes derived from miRNA transfected MSCs could be used to modulate tumor progress as the anticancer vehicles.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.309-314
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• 2013

Aim: Brain tumors almost universally have fatal outcomes; new therapeutics are desperately needed and will only come from improved understandins of glioma biology. Methods: Exosomes are endosomally derived 30~100 nm membranous vesicles released from many cell types. Examples from GL26 cells were here purified using density gradient ultracentrifugation and monitored for effects on GL26 tumor growth in C57BL/6j mice (H-2b). Lactate dehydrogenase release assays were used to detect the cytotoxic activity of CD8+T and NK cells. Percentages of immune cells producing intracellular cytokines were analyzed by FACS. Results: In this study, exosomes from murine-derived GL26 cells significantly promoted in vivo tumor growth in GL26-bearing B6 mice. Then we further analyzed the effects of the GL26 cells-derived exosomes on immune cells including CD8+T, CD4+T and NK cells. Inhibition of CD8+T cell cytotoxic activity was demonstrated by CD8+T cell depletion assays in vivo and LDH release assays in vitro. The treatment of mice with exosomes also led to a reduction in the percentages of CD8+T cells in splenocytes as determined by FACS analysis. Key features of CD8+T cell activity were inhibited, including release of IFN-gamma and granzyme B. There were no effects of exosomes on CD4+T cells and NK cells. Conclusion: Based on our data, for the first time we demonstrated that exosomes from murine derived GL26 cells promote the tumor growth by inhibition of CD8+T cells in vivo and thus may be a potential therapeutic target.

• 생명과학회지
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• 제21권8호
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• pp.1076-1082
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• 2011

미세소관(microtubule) 위를 이동하는 키네신은 분비소포를 이동시키는 운동단백질이다. KIF5s (KIF5A, KIF5B and KIF5C)는 세포막으로 싸인 각종 세포 내 소기관과 결합하여 미세소관을 따라 목적지까지 이동시킨다는 결과는 알려져 있지만, 어떻게 상대의 cargo를 인식하는지는 밝혀지지 않았다. 본 연구는 KIF5B의 결합 단백질을 동정하기 위하여 효모 two-hybrid system을 사용하여 KIF5B와 특이적으로 결합하는 Myo9b을 확인하였다. Myo9b는 액틴위를 이동하는 운동단백질로 다른 KIF5s들과도 결합함을 효모 two-hybrid assay로 확인하였다. 또한 Myo9s의 GTPase 활성화 단백질(GAP) 영역은 KIF5B와 결합하는데 필수영역임을 확인하였고, 이러한 단백질간의 결합은 Glutathione S-transferase (GST) pull-down assay를 통하여서도 확인하였다. 생쥐의 뇌 파쇄액에 KIF5B들의 항체로 면역침강을 행하여 Myo9s 단백질을 확인한 결과, KIF5s는 Myo9s 단백질과 특이적으로 함께 침강하였다. 이러한 결과들은 kinesin-I는 액틴 결합 운동단백질과 직접 결합함을 보여준다.

• 한국동물학회지
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• 제33권1호
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• pp.78-93
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• 1990

생쥐가 성숙하는 동안 부정소 상피세포의 분화와 부정소액의 분비 및 흡수와 관련된 미세구조의 변화를 알아보고자, 생후 10, 20, 35 그리고 80일 된 생쥐에서 부정소 상피세포를 전자현미경으로 관찰하였다. 생쥐 부정소의 분화과정은 미세구조의 특징에 따라 생후 20일가지의 미분화기, 생후 35일 전후의 성장 및 분화기, 그리고 성체의 성숙기로 구분되었다. 각 시기는 정소에서 세정관의 강소 형성시기 그리고 정소액과 더불어 정자가 부정소에 유입되는 시기와 밀접한 관계가 있었다. 성체의 부정소 상피세포 중 주세포는 두부 부정소 기부에서 흡수 기능을 갖는 구조였고, 두부의 말부와 체부 그리고 미부에서는 조면소포체와 골지체가 발달되어 단백질 합성과 분비가 왕성한 구조로 관찰되었다. 투명세포는 주로 체부와 미부에 존재하였으며 세포질내에 흡수과립이 많이 존재하였고, 그 속에는 정자에서 분리된 세포질 잔기로 사료되는 막구조물이 관찰되었다. 부정소 부위에 따라 상피세포의 종류와 분포가 달랐고, 동일한 종류이 상피세포라도 부위별로 미세구조가 다르게 관찰되었다.

• 한국가축번식학회지
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• 제16권1호
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• pp.21-38
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• 1992

The present study was carried out to investigate morphologic changes in the corpus luteum of the pregnant rat by electron microscope after administration of prostaglandin F2$\alpha$(PGF2$\alpha$). Pregnant rates were treated with PGF2$\alpha$(1,500$\mu\textrm{g}$/rat) and their corpura lutea were observed morphologically. The results obtained in this study were summarized as follows ; 1. The weight of the ovaries and corpura lutea were decreased slightly at 8~24 hours after PGF2$\alpha$ administratin but no significant differences were observed. 2. The number of corpora lutea and luteal cells decreased slightly at 12~48 hours and 18~24 hours after PGF2$\alpha$ tretment but there were no signifciant differences between control and treatment. 3. The weight of uterus and the unmber of embryo decreased slightly at 96 hours and at 18~96 hours after PGF2$\alpha$ administration but no significant differences were obtained. 4. In the electron microscopic observatons, lipid droplets which are electron dense and appear in the cytoplasm moderately increased in number after PGF2$\alpha$ treatment. The lipid droplets were surrounded by mitochodria and appeared in the autophagic vacuoles. 5. Moderated and high electron dense mitochondria which are round or elongated in shape showed pleomorphism from 3 hours after PGF2$\alpha$ treatment. Destruction of tubular of vesicular cristae was observed at 6 hours after the treatment. Dense body and myelin figures in matrix of mitochondria were also appeared. 6. Well-developed smooth endoplasmic reticulum(sER) showed tubular or vesicular cisternae. A number of whorl membranes containing ribosomes, mitochondria and lipid droplets were observed at 1.5 hour after treatment. sER was abundant in luteal cells at 12 hours were treatment. 7. Well-developed Golgi pparatus appeared obviously 6 hours and more prominently at 12 hours. Those Golgi vesicles were remarkably dilated. 8. Generally, a few rough endoplasmic reticulum (rER) were appeared after treatment and cisternae showed slight dilatation. No differences among the treatments were observed. However, slight dilation of cisternae was observed at 1.5 hours after treatment. 9. Ribosomes composed of free and polyribosomes were abundant before treatment but polyribosomes were appeared at 12 to 24 hours after treatment. 10. Intercellular space were slightly extended at 3 hours and markedly extended at 12 hours. Numerous microvillous protrusions were observed at these times. Membranous multivesicular structures and autophagic vacuoles were also appeared in the intercellular space. 11. At 3 hours after the treatment, autophagic vacuoles appeared in the cytoplasm of the cell. They increased in number with time and were observed to transfer to the intercellular space. Lysosomal dense body appeared in the cytoplasm and the inclusion body was also observed in nucleus at 12 to 24 hours after treatment.

• Applied Microscopy
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• 제6권1호
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• pp.21-32
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• 1976

Rhizopus nigricans, Aspergillus niger, Aspergillus ochraceus의 균계 Agricus bisporus, Rhizopogon rubescens의 자실층균계 및 담자기세포, Marchantia polymorpha, Pogonatum inflexum, Pteridium aqiulium 의 동화조직, Pinus densiflora, Ginkgo biloba, Panax ginseng 의 엽육조직의 소편을 glutaralehyde-paraformalehyde 및 $OsO_4$에 고정하여 다소포체 및 세포질용해체와 관련된 다양상인 막성구조의 기원과 기능에 관하여 전 자현미경적으로 추구하였다. Rhizopus nigricans, Aspergillus niger, A. ochraceus, Agricus bisporus, Rhizopogon rubescens 의 동심원상인 다층막, 미에린一소포-관상구조의 복합체, 평행다층막구조등은 원형질막에서 유래된다. Marchantia polymorpha, Pogonatum inflexum, Pteridium aquilinum, Pinus densiflora, Ginkgo biloba, Panax ginseng 에 있어서 pinocytotic vesicles 외에 다양상안 막성구조는 원형질막과 세포질안의 무과립성 소포체에서 유래된다. 원형질막에서 유래되는 것은 다소포체인 것과 미에린 양구조인 것으로 구분되고, 이것은 2차액포를 형성하거나 또는 1차액포안으로 유리되어 퇴화한다. 세포질안의 소포체가 세포질의 일부를 포위하고 그 내부에 막증식과 더불어 세포질이 감소되면서 다층막구조로 변하고, 이것은 액포안으로 유리되어 퇴화한다. 세포질의 소포체에서 유래되는 것은 액포분화와 밀접한 관계가 있는 세포질분리체 또는 세포용해체인 것으로 믿어진다.