At the end of the session the students should be able to:
Describe the different types of WBCs.
Explain the development of leucocytes (leucopoiesis).
Discuss the function of different types of WBCs.
Describe the mechanism of phagocytosis.
med_students0
At the end of the session the students should be able to:
Describe the different types of WBCs.
Explain the development of leucocytes (leucopoiesis).
Discuss the function of different types of WBCs.
Describe the mechanism of phagocytosis.
med_students0
Slideshow is from the University of Michigan Medical School’s M2 Hematology / Oncology sequence
View additional course materials on Open.Michigan: openmi.ch/med-M2Hematology
It has long been assumed that the individual cisternal stacks that comprise the plant Golgi apparatus multiply
by some kind of fission process. However, more recently, it has been demonstrated that the Golgi apparatus
can be experimentally disassembled and the reformation process from the ER (endoplasmic reticulum)
monitored sequentially using confocal fluorescence and electron microscopy. Some other evidence suggests
that Golgi stacks may arise de novo in cells. In the present paper, we review some of the more recent
findings on plant Golgi stack biogenesis and propose a new model for their growth de novo from ER exit
sites.
What is white blood cells?
WBCs, also called leukocytes, are an important part of the immune system. These cells help fight
infections by attacking bacteria, viruses, and germs that invade the body.
Hematophoisis is the synthesis of all blood cells within the bone marrow under the influence of certain hormones and growth factors, what are the different step, stages, and factors are given in this presentation
ISEV2014 - Introduction to EV biogenesis and secretion (C. Thery)andyfhill
Slides from ISEV2014 presentation. Introduction to Extracellular Vesicle biogenesis and secretion presented by Clotilde Thery.
For more information go to www.isev.org
What process is used to obtain cells from bone marrow and normal peripheral blood?
What is the best cell counting and viability method for primary cells?
AllCells, your primary cells research partner, and Nexcelom Bioscience, your cell counting experts, have joined together in an exclusive collaboration to host a free webinar to help educate researchers and present data from their own experiences.
Vascular diseases are increasing health problems affecting > 25 million individuals in westernized societies. Such patients could benefit from transplantation of tissue-engineered vascular grafts using autologous cells. One challenge that has limited this development is the need for cell isolation, and risks associated with ex vivo expanded stem cells. Here we demonstrate a novel approach to generate transplantable vascular grafts using decellularized allogeneic vascular scaffolds, repopulated with peripheral whole blood (PWB) in vitro in a bioreactor. Circulating, VEGFR-2 +/CD45 + and a smaller fraction of VEGFR-2 +/CD14 + cells contributed to repopulation of the graft. SEM micrographs showed flat cells on the luminal surface of the grafts consistent with endothelial cells. For clinical validation, two autologous PWB tissue-engineered vein conduits were prepared and successfully used for by-pass procedures in two pediatric patients. These results provide a proof of principle for the generation of transplantable vascular grafts using a simple autologous blood sample, making it clinically feasible globally.
Hematopoiesis is the process of blood cells being differentiated from hematopoietic stem cells. This process must be repeated on a regular basis in order to keep the body's circulating blood cell numbers stable. Blood cells are divided into three main linages:
Reticulocytes and erythrocytes make up the Erythroid Lineage (red blood cells).
Lymphocytes (B and T cells) and natural killer cells make up the lymphoid lineage.
Macrophages, dendritic cells, granulocytes, and megakaryocytes are all members of the myeloid lineage.
## Site Of Hematopoiesis
Yolk sac
Liver and spleen
Bone marrow
Gradual replacement of active (red) marrow by tissue inactive (fatty)
Expansion can occur during increased need for cell production
The differences between a cow and a monkey are clear. It is easy to tell a moth from a mosquito. So why are there still scientific studies that mix them up? The answer is simple: hundreds of cell lines stored and used by modern laboratories have been wrongly identified. Some pig cells are labelled as coming from a chicken; cell lines advertised as human have been shown to contain material from hamsters, rats, mice and monkeys. Problems have already been found with more than 400 cell lines. (Cited from Nature 520 (2015)).
An increasing number of scientific publications (i.e. Nature journals) are now sistematically asking for cell line authentication at the moment of paper submission. To help researchers to meet this requirement, UAT is starting to offer a new service for human cell line authentication.
Slideshow is from the University of Michigan Medical School’s M2 Hematology / Oncology sequence
View additional course materials on Open.Michigan: openmi.ch/med-M2Hematology
It has long been assumed that the individual cisternal stacks that comprise the plant Golgi apparatus multiply
by some kind of fission process. However, more recently, it has been demonstrated that the Golgi apparatus
can be experimentally disassembled and the reformation process from the ER (endoplasmic reticulum)
monitored sequentially using confocal fluorescence and electron microscopy. Some other evidence suggests
that Golgi stacks may arise de novo in cells. In the present paper, we review some of the more recent
findings on plant Golgi stack biogenesis and propose a new model for their growth de novo from ER exit
sites.
What is white blood cells?
WBCs, also called leukocytes, are an important part of the immune system. These cells help fight
infections by attacking bacteria, viruses, and germs that invade the body.
Hematophoisis is the synthesis of all blood cells within the bone marrow under the influence of certain hormones and growth factors, what are the different step, stages, and factors are given in this presentation
ISEV2014 - Introduction to EV biogenesis and secretion (C. Thery)andyfhill
Slides from ISEV2014 presentation. Introduction to Extracellular Vesicle biogenesis and secretion presented by Clotilde Thery.
For more information go to www.isev.org
What process is used to obtain cells from bone marrow and normal peripheral blood?
What is the best cell counting and viability method for primary cells?
AllCells, your primary cells research partner, and Nexcelom Bioscience, your cell counting experts, have joined together in an exclusive collaboration to host a free webinar to help educate researchers and present data from their own experiences.
Vascular diseases are increasing health problems affecting > 25 million individuals in westernized societies. Such patients could benefit from transplantation of tissue-engineered vascular grafts using autologous cells. One challenge that has limited this development is the need for cell isolation, and risks associated with ex vivo expanded stem cells. Here we demonstrate a novel approach to generate transplantable vascular grafts using decellularized allogeneic vascular scaffolds, repopulated with peripheral whole blood (PWB) in vitro in a bioreactor. Circulating, VEGFR-2 +/CD45 + and a smaller fraction of VEGFR-2 +/CD14 + cells contributed to repopulation of the graft. SEM micrographs showed flat cells on the luminal surface of the grafts consistent with endothelial cells. For clinical validation, two autologous PWB tissue-engineered vein conduits were prepared and successfully used for by-pass procedures in two pediatric patients. These results provide a proof of principle for the generation of transplantable vascular grafts using a simple autologous blood sample, making it clinically feasible globally.
Hematopoiesis is the process of blood cells being differentiated from hematopoietic stem cells. This process must be repeated on a regular basis in order to keep the body's circulating blood cell numbers stable. Blood cells are divided into three main linages:
Reticulocytes and erythrocytes make up the Erythroid Lineage (red blood cells).
Lymphocytes (B and T cells) and natural killer cells make up the lymphoid lineage.
Macrophages, dendritic cells, granulocytes, and megakaryocytes are all members of the myeloid lineage.
## Site Of Hematopoiesis
Yolk sac
Liver and spleen
Bone marrow
Gradual replacement of active (red) marrow by tissue inactive (fatty)
Expansion can occur during increased need for cell production
The differences between a cow and a monkey are clear. It is easy to tell a moth from a mosquito. So why are there still scientific studies that mix them up? The answer is simple: hundreds of cell lines stored and used by modern laboratories have been wrongly identified. Some pig cells are labelled as coming from a chicken; cell lines advertised as human have been shown to contain material from hamsters, rats, mice and monkeys. Problems have already been found with more than 400 cell lines. (Cited from Nature 520 (2015)).
An increasing number of scientific publications (i.e. Nature journals) are now sistematically asking for cell line authentication at the moment of paper submission. To help researchers to meet this requirement, UAT is starting to offer a new service for human cell line authentication.
Presentación del MIDAS (Mixed-Data Sampling): En ella exploramos no sólo la metodología MIDAS para estimar el PIB en tiempo real, sino que también utilizamos una metodología innovadora (Bayesian Model Averaging) para la selección de variables; además de explorar las ventajas de combinar las predicciones de varios modelos.
Posters announcing the first COMPREHENSIVE 3D printing workshops in Stockholm by Fenno3D and hosted by Inkonova in Makerspark.
More info at: https://www.fenno3d.fi/en/shop/workshops/stockholm-3d-printing-workshop-q1/
Este material es una revelación profética que nos enseña a discernir entre lo santo y profano. Requisito esencial para el nuevo sacerdocio que ministrará en los altares del Eterno en la tierra
Carla Basili (Istituto IRCrES-Istituto di Ricerca sulla Crescita Economica Sostenibile del Consiglio Nazionale delle Ricerche e European Network on Information Literacy) tratta di Information Literacy al seminario “Competenze digitali: da information literacy a transliteracy" organizzato da UniPR Co-Lab presso l'Università di Pama il 10 marzo 2015.
Histophysiology and Histochemical Analysis of the Saccus Vasculosus of Butter...Akhil Gupta
Cellular details including histochemical nature and functional aspects of saccus vasculosus in Ompok bimaculatus (Bloch, 1794) were studied using histological and histochemical techniques. The oval protruded saccus vasculosus
situated on the ventral side of the diencephalon behind the pituitary. This circumventricular organ contained atypical large central lumen lined by single stratified ithelium with characteristic coronet cells and supporting cells.
Silver stain was adopted for the occurrence and distribution of neurons if any in the epithelium and various regions
of the saccus vasculosus. Intensity of glycogen was found to be associated with the coronet cells and blood vessels.
Histochemical localization of basic protein and bound lipid were recorded in the cells of saccus epithelial lining as
well as in the blood vessels. Coronet cells perhaps involved in secretory as well as sensory function of the fish concerned.
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Of all the body systems, the lymphatic system is perhaps the least familiar to most people. Yet without it, neither the circulatory system nor the immune system could function—circulation would shut down from fluid loss, and the body would be overrun by infection for lack of immunity.
The origins of the endoneurial collagen of peripheral nerves and their roots have
not yet been determined. Ochoa (1976) has recently commented upon the presence
of collagen in endoneurial clefts some weeks before the earliest appearance of endoneurial
fibroblasts and consequently attributed collagen production to the immediately
adjacent Schwann cells. The occurrence of collagen in 'pockets' invaginated
into the Schwann cells of unmyelinated fibres (Gamble, 1964) was interpreted as
showing a tendency in such cells to enwrap any suitably sized and orientated structure,
but Thomas (1973) thought the phenomenon more probably indicative of a
capacity of Schwann cells to replace degenerated axons with newly formed collagen.
It was remarked also (Ochoa, 1971) that although collagen pockets may be quite
numerous in young adult human nerves they had not appeared in the sural nerve of
a human fetus of 18 weeks of intrauterine life, i.e. at a stage of development when Schwann cells are extremely active in the establishment of complex interrelationships with unmyelinated axons. In the course of work directed to the study of the development of the human trochlear nerve some observations have been made which are pertinent to the problem of the origin of the endoneurial collagen. They are reported and discussed below.
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Memorandum Of Association Constitution of Company.pptseri bangash
www.seribangash.com
A Memorandum of Association (MOA) is a legal document that outlines the fundamental principles and objectives upon which a company operates. It serves as the company's charter or constitution and defines the scope of its activities. Here's a detailed note on the MOA:
Contents of Memorandum of Association:
Name Clause: This clause states the name of the company, which should end with words like "Limited" or "Ltd." for a public limited company and "Private Limited" or "Pvt. Ltd." for a private limited company.
https://seribangash.com/article-of-association-is-legal-doc-of-company/
Registered Office Clause: It specifies the location where the company's registered office is situated. This office is where all official communications and notices are sent.
Objective Clause: This clause delineates the main objectives for which the company is formed. It's important to define these objectives clearly, as the company cannot undertake activities beyond those mentioned in this clause.
www.seribangash.com
Liability Clause: It outlines the extent of liability of the company's members. In the case of companies limited by shares, the liability of members is limited to the amount unpaid on their shares. For companies limited by guarantee, members' liability is limited to the amount they undertake to contribute if the company is wound up.
https://seribangash.com/promotors-is-person-conceived-formation-company/
Capital Clause: This clause specifies the authorized capital of the company, i.e., the maximum amount of share capital the company is authorized to issue. It also mentions the division of this capital into shares and their respective nominal value.
Association Clause: It simply states that the subscribers wish to form a company and agree to become members of it, in accordance with the terms of the MOA.
Importance of Memorandum of Association:
Legal Requirement: The MOA is a legal requirement for the formation of a company. It must be filed with the Registrar of Companies during the incorporation process.
Constitutional Document: It serves as the company's constitutional document, defining its scope, powers, and limitations.
Protection of Members: It protects the interests of the company's members by clearly defining the objectives and limiting their liability.
External Communication: It provides clarity to external parties, such as investors, creditors, and regulatory authorities, regarding the company's objectives and powers.
https://seribangash.com/difference-public-and-private-company-law/
Binding Authority: The company and its members are bound by the provisions of the MOA. Any action taken beyond its scope may be considered ultra vires (beyond the powers) of the company and therefore void.
Amendment of MOA:
While the MOA lays down the company's fundamental principles, it is not entirely immutable. It can be amended, but only under specific circumstances and in compliance with legal procedures. Amendments typically require shareholder
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A personal brand exploration presentation summarizes an individual's unique qualities and goals, covering strengths, values, passions, and target audience. It helps individuals understand what makes them stand out, their desired image, and how they aim to achieve it.
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RMD24 | Debunking the non-endemic revenue myth Marvin Vacquier Droop | First ...BBPMedia1
Marvin neemt je in deze presentatie mee in de voordelen van non-endemic advertising op retail media netwerken. Hij brengt ook de uitdagingen in beeld die de markt op dit moment heeft op het gebied van retail media voor niet-leveranciers.
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Grote partijen zijn al een tijdje onderweg met retail media. Ondertussen worden in dit domein ook de kansen zichtbaar voor andere spelers in de markt. Maar met die kansen ontstaan ook vragen: Zelf retail media worden of erop adverteren? In welke fase van de funnel past het en hoe integreer je het in een mediaplan? Wat is nu precies het verschil met marketplaces en Programmatic ads? In dit half uur beslechten we de dilemma's en krijg je antwoorden op wanneer het voor jou tijd is om de volgende stap te zetten.
Unveiling the Secrets How Does Generative AI Work.pdfSam H
At its core, generative artificial intelligence relies on the concept of generative models, which serve as engines that churn out entirely new data resembling their training data. It is like a sculptor who has studied so many forms found in nature and then uses this knowledge to create sculptures from his imagination that have never been seen before anywhere else. If taken to cyberspace, gans work almost the same way.
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Improving profitability for small businessBen Wann
In this comprehensive presentation, we will explore strategies and practical tips for enhancing profitability in small businesses. Tailored to meet the unique challenges faced by small enterprises, this session covers various aspects that directly impact the bottom line. Attendees will learn how to optimize operational efficiency, manage expenses, and increase revenue through innovative marketing and customer engagement techniques.
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1. a-
Separatum TXPERITNTIA 3/, 837 (1975)
Birkhduser Verlag, Basel (Schweiz)
An Autoradio$raphic Demonstration of Blood Cell Renewal in Styela claaa (tJrochordata:
Ascidiacea)
The blood cells of ascidians circulate in the blood chan- Mnterials and meth,ods. Specimens of Styeta claua were
nels and wander throughout the tissues and the tunic. collected from Mission Bry, San Diego, California, IJSA
Although some blood cell types are common to all asci- and inj ected intra-atrially with 1 pCi of tritiated thymidine
dians, other blood ceIl types often differ from species to (New England Nuclear corp.) per g fresh weight. The
species. The number of blood cells described in any one aqueous solution of tritiated thymidine (specific activitv
species also varies with the morphological criteria of the 6.7 Cilrrrlw) was diluted with an equal volume of 2 times
authors. With iight microscopy, 8 types have been describ- concentrated sea water before use" 3 individuals were
ed in Styela claual while 5 types have been described in sacrificed by fixation in Bouin's fluid at each of the follow-
Styela pl'icataz " ing time intervals : J- h, La, 20 and 60 days. The body wall
The origin and renewal of ascidian blood cells have been and digestive tract were dissected out, dehydrated,, and
the subject of controversy. The neural gtand3 and haemo- embedded in paraffin" 7 pm sections were cor.ered with
blasts in the connective tissue a have been reportecL as Kodak Nuclear Track Emulsion type NBT-2 by the
sites of biood cell formation. Several authors have dipping method and stored at 4 oC for periods of 2 weeks
remarked on the absence of mitotic figures in the blood to 2 months" Autoradiograms were developed in Kodak
spaces 5, 6" There is general agreement that the lymphocyte D-l9 developer (3 min), and sections were stained through
is the progenitor biood cell type. Vhether l1'mphocyte cell the emulsion with hematoxylin"
division occurs only in the lymph nodules of the body wall Resr't'lts. 3 types of blood cells can be recognrzed in
and digestive tract6 or both in the lymph nodules and in autoradiograms: the lymphocyte, the leucocyte, and the
the circulating blood 1, 2 has not been established. In vacuolated cell. A11 3 blood cell types occur free in the
either case, the lymphocytes are presumed to differentiate circulating blood and clustered in lymph nodules within
into the other cetrI types by the loss of the nucleolus, an the connective tissue of the body. In the body wall, the
increase in the amount of crrtoplasm, and the acquisition lymph nodules occur in patches immediateiy adjacent to
of various cytoplasmic inclusions and vacuoles. The the atrial epithelium (the internal lining of the body wa1l).
transformations of one blood cell type to another have In the digestive tract, they are most concentrated in the
been deduced from morphological criteria alon e2, ? . branchiai wall"
rn the present investigation, autoradiography with
tritiated thymidine was used to locahze sites of blood cell
proliferation and determine possibie blood cell transforma- r'W. C. GronGE, Q. J1. microsc. Sci. Bl,391_ (1939).
tions in the ascidian Styela claua. A short exposure to 2 T" onuvn, Sci. Rep. Res. Insts Tohuku t]niv., Bio1. l l, rgr (1936).
3 L. Cuf Nor, Archs ZooI" exp. gdn. g, 13 (189j ).
tritiated thymidine labeled blood cells engaged in pre- * J. M. Pfnis, Annis Inst. oc6anogr., Monaco 2/,229 (19,t3).
mitotic DNA synthesis. By sampling tissues at increasing 5 M. Korr.lra.x, Annls Sci. nat., Zoo7.8,
1 (1908).
time intervals after this short exposure, the fate of the 6 R" H" Mrrran, L.h'I.B.c. {ern. typ.Br. mar. pl.
Anim. ss, (1953).
proliferating cells was f ollowed "
7 R" ExDEAN,
Q. Jl.microsc. Sci. /0l , M (1960).
"u* *=*"+*n
.jii,ffi:,,,,,,,,
$::::Iri::::::::::::::
: ] :: :::::::i:::
F ig. 1. An autoradiogram of the lymph nodules in the body wall of Fig. 2. An autoradiogram of the lymph nodules in the body wali of
Styela claua t h after the injection of tritiated thymidine. x 600" Styela claua 60 days after the injection
of tritiated thymidine. The
blood celis are no longer labeled although several atrial epithelial
celis (arrows) are still labeled. m, muscle. x 600.
2. /-
838 Specialia ExpBnrBNrrA 3tl7
Lymphocytes are small, round to oval cells approximate- labeled, but few lymphocytes were labeled any longer.
ly 6-8 pm in diameter with a large nucleolated nucleus. Most of the labeled cells, both in the lymph nodules and
The nucleus fills most of the cell and is surrounded by a in the circulating blood, were leucocytes and vacuolated
small amount of basophilic cytoplasm. Several lymphocy- cells. At 60 days after the administration of tritiated
tes frequently cluster together in the interior of the lymph thymidine, most of the blood cells in the lymph nodules
nodules. Cell boundaries are difficult to distinguish as the were unlabeled (Figure 2). llowever a few scattered
Iarge basophilic nuclei of adjacent cells crowd each other labeled leucocytes and vacuolated cells occurred in the
with little intervening cytoplasm. connective tissue below the atrial epithelium and in the
Leucocytes are large blood cells about L}-L+ pm in blood channels.
diameter with a small, basophilic nucleus which is eccen- D'iscuss'ion. The blood cells of. Styela claua constitute a
trically displaced and lacks a conspicuous nucleolus. renewing 8 cell system with a renewal time on the order of
Most of the cell is filled with slightly basophilic cytoplasm. several weeks. As suggested by other authors 1' 2, blood
Leucocytes range in shape from spherical to oval and cell proliferation occurs both in the lymph nodules and in
may have several cytoplasmic processes. The cytoplasm the blood channels. The possible blood cell transforma-
may be granular or transparent and may contain a large tions are shown in Figure 3. Although both lymphocytes
basophilic inclusion. Leucocytes probably include several and leucocytes proliferate, the lymphocyte is probably
cell types which are difficult to distinguish from each the more primitive blood cell type. It is ultrastructurally
other. In the lymph nodules, the abundant cytoplasm the most undifferentiated blood cell type e and may also
around each nucleus produces regions of light basophilia be capable of differentiating into germinal cells 10 and
and makes the leucocyte nucleus easily distinguished from somatic cells other than blood cells 11. Presumably the
the lymphocyte nucleus. lymphocytes differentiate into leucocytes. llowever,
Vacuolated cells are the largest of the blood cells, being since the leucocytes divide and also probably represent
roughly 16-18 pm long. The nucleus is eccentrically several separate cell types, the leucocytes themselves
placed and lacks a conspicuous nucleolus. Within the might be composed of stem, dividing transit, or non-
cytoplasm, the vacuolated cells contain numerous vacu- dividing transit 12 components. Since the differentiated
oles which are clear or yellow in hematoxylin stained vacuolated cells do not divide, they must be differentiating
sections and which have a high index of refraction. from a precursor cell type; whether this precursor is a
Vacuolated cells frequently lie embed d ed between the lymphocyte or a leucocyte could not be determined in the
atrial epithelium and the connective tissue of the body present investigation. Based upon morphological criteria,
wall. however, vacuolated cells have been reported to differen-
A t h exposure to tritiated thymidine labeled many tiate from intermediate cell types and not from lympho-
blood cells in the body. Blood cells were labeled. both in cytes in other ascidians 7 , L3.
the lymph nodules and in the blood channels. In the Blood cells are renewed in insects 1a and mammals 15
Iymph nodules, both lymphocytes and leucocytes wero but not in echinoderms 16 where blood cells have charac-
labeled (Figure 1), and labeled nuclei were frequentlv teristics of expandirg* cell populations. In mammals,
clustered in small groups. Probably no vacuolated cells proliferating cells are most concentrated in the bone
were labeled at this time ; however, positive reaction s marrow, lymph nodes, and spleen, but, like tn Styela, they
were difficult to detect in autoradiograms as the vacuoles also occur in the circulating blood and in the connective
appear very similar to out-of-focus silver grains. ti$sue. In Styela, other elements of the vascular system
By 20 days after injection, most of the labeled cells in (the heart and connective tissue lining the blood channels)
the lymph nodules occurred in the peripheral parts of the comprise expanding cell populations 17.
nodules. Some vacuolated cells were now unequivocally
Surnrnary. The blood cells of Styela claua were shown
by autoradiography r,vith tritiated thymidine to be renew-
ed after several weeks. Proliferating lymphocytes and
leucocytes occurred in the lymph nodules and blood
channels of the body. Vacuolated cells did not proliferate
but differentiated from a precursor cell type.
T. H. ERnrax 18
D'iu'is'ion, of Marine B'iology,
Scri,pps Inst'itut'ion of Oceanography,
La Jolla (Cali,forn'ia 92037, USA), 5 March 7 975.
I f, 8
e
B. MBSSTER and C. P. LBnroND, Am. J. Anat. 106,247 (1960).
J. OvnRroN, J. Morph.779,305 (1966).
10 A. T. NBwBERRv,
11 G. F'nnBnreN,
t'J. E. Cr,Bevnn,
J. Morph.726, t23 (1,968).
J. exp. Zool.756,I57 (7964).
Thyrnid,ine Metabol,ism and, CeII, Kinetics (John
Wiley & Sons, fnc., New York 1,967).
13 A. SansA.nrN, Arch. ital. Anat. Embriol . 60,33 (1955).
14 E. P. CnoNKrrE, V. P. BoNn, T. M. Fr,rBnNnn and
J. R. RunrNr,
Lab. fnvest. 8,263 (1959).
15 S. C. SsnrvASrAvA and A. G. RrcsARD, Biol. Bull. 728,337 (1965).
16 N. D. Holr,AND,
J. H. Pnrr-r,rps and A. C. Grnsr, Biol. Bull. 128,
zse (Le6s).
L7 T. H. Ennar, Ph. D. Diss. (1975).
Fig. 3. Transformation of blood cell typesin Styela claaa. A, lympho- 18 Present address: Department of. ZooIogy, University of California,
cyte; B, leucocyte; C, vacuolated cell. Berkeley, California 94720, USA.