Face to face-Lectures

The teaching of the course consists of lectures and laboratory exercises.

Laboratory exercises (in 2 student groups of students,2 instructors per group of 10 students) composing the students' practical are complementary to the lectures and they aim to familiarize the student with the operation of simple laboratory instruments and the experimental procedures that are often used in diagnosis as well as to help the students comprehend concepts that are not easily presented theoretically (learning based on practical experience).

Attending the lectures is not compulsory. Attending the laboratory exercises is mandatory.

Information and Communication Technologies are used for the preparation of lecture materials, electronic information and the provision of supplementary learning materials to students.

In particular: The lessons are taught using the means used to teach the lessons:

– Common software (eg MS powerpoint) is used to prepare lecture material and display slides and videos.

– The study guide (detailed supplementary material & additional bibliography), the theory and protocols of laboratory exercises, the slides of each lecture as well as related videos and scientific articles are available electronically and online to students through the e-class system of our university.

– Information about the course, the lecturers and their research interests and in general the Biology Laboratory of the School of Medicine is available online through our university's e-class system.

– Common software (eg MS excel) is used for the statistical processing of student evaluation.

Announcements, information, etc. are available online through e-class. Communication is also done via email and MS-TEAMS

The evaluation language is Greek.

Evaluation methods.

A. For the laboratory practice: Lab Papers, Written exam at the end of the semester with multiple choice questions and problem solving.

The participation of the students in the laboratory exercises as well as the written report of the results of the exercises is mandatory. The report includes the results (presented in tables and graphs, as well as the conclusions (e.g. whether the results were as expected, if not why, sources of possible errors in the experiments) as requested by each exercise. At the end of each exercise, the written report is checked by the instructors. At the end of the semester, the students are examined in the content of the laboratory exercises. The examined material consists of the theory, the methodology and the methods of processing the results, as included in the Laboratory Practice Guide or presented by the teachers. during the exercises. Only students who have successfully completed the laboratory exercises can participate in the written laboratory examinations. Success in the laboratory examination is a prerequisite for participation in the course examinations.

B. For the lecture material: The course exams are written, last 2 hours, and consist of multiple choice questions and critical or short answer questions. The exam material is the lectures as described above. Only those students who have successfully passed the laboratory exams have the right to participate in the course exams.

Final grade:

The final grade of the course is calculated as the sum of the 80% grade of the written course exams and the 20% grade of the written laboratory exams.

The general purpose of the course is to introduce students to the biology of the cell, as the basic structural and functional unit of the phenomenon of life. In particular, the physiological properties of cells are analyzed, their structure, their organelles, their interactions with each other and with the environment, as well as the way in which they ensure the necessary energy, their life cycle, their division and their death. Particular emphasis is placed on the analysis of the structure of biological membranes and their role in the transport of molecules through them as well as in the communication between intracellular compartments. The signal transmission from the extracellular space to the cell's response (movement, division/death or change in gene expression) as well as the modes of intercellular communication are also thoroughly analyzed while the importance of signaling dysfunction in the etiology of human diseases is also highlighted. Great importance is also given to the description of the process of cell division and death and to the analysis of the strict and multi-level regulation of these processes, in order for the student to understand the importance of their deregulation in the occurrence of diseases, such as cancer. Furthermore, the course seeks to provide students with the basic elements to understand the impact of cell function disturbances on the homeostasis of the organism and the occurrence of human diseases, which the student will be called upon to recognize and deal with in the future as a physician.

The specific objectives of the course are specialized in the following intended learning outcomes:

Upon successful completion of the course, the student will:

• Has a basic understanding of cell biology and the differences between prokaryotic/eukaryotic organisms
• Has a basic understanding of the biology of supramolecular structures (viruses, prions)
• Can distinguish subcellular organelles and has knowledge of their functions
• He has understood the structure and functional importance of membranes for the cell
• Has understood how cells communicate (signal transduction)
• Has understood the cell life cycle (growth, mitosis/decrease, cell death)
• Has basic knowledge of the organization of cells in tissues/organs
• Has understood the concept of cellular homeostasis and the basic effects of its disturbance as the basis of the manifestation of diseases
• Has knowledge of basic techniques/instruments for the study of cells (microscopy, fractionation)
• It is able to distinguish the different cell types of the blood and can determine a person's blood type
• Has understood the principles of a serological diagnostic method (ELISA), can perceive the result and make the diagnosis
• It can recognize and distinguish cell cycle/mitosis phases and calculate the mitotic index

He is fluent in the use of the microscope and the basic instruments of the laboratory (pipettes, centrifuges, etc.)

Theory/Modules:
• Unit 1: Introduction: The importance of cell biology in Medicine
Cell biology and its tools at the service of modern medicine - The importance of the Human Cell Atlas - The next great challenge of bioscientists (recording all cell types and subtypes in the human body, mapping cell types and their location within tissues , distinction between dormant, activated, differentiated cell, distinction of healthy cell from pathological).

• Unit 2: Biomolecules-The chemical composition of cells
The chemistry of life, Chemical bonds (covalent, ionic bonds), Biomolecules: sugars, fatty acids, amino acids, nucleotides, Macromolecules: polysaccharides, lipids, proteins, nucleic acids.

• Unit 3: Structure and function of proteins
Amino acids, peptides, peptide bond, polypeptide chains, Shape determines the function of proteins, Primary, secondary, tertiary, quaternary structure, Protein families, How proteins work - Enzymes, structure and action - Antibodies, structure and action. Basic principles of a serological diagnosis method-ELISA, How we study proteins-Protein electrophoresis

• Unit 4: Supramolecular structures (phages-viruses-prions)
Structure of viruses, Classification of viruses, Viruses and host range, DNA viruses (adenoviruses, Papillomavirus), RNA viruses (positive polarity, negative polarity)- Retroviruses, coronaviruses, etc., Viruses of bacteria: phages-Lytic cycle-Lysogenic cycle, Animal Viruses: Human Immunodeficiency Virus (HIV- Acquired Immune Deficiency Syndrome (AIDS), Viroids, Prions- Mad Cow Disease, Creuztfeldt-Jakob Disease, Virus Diagnosis.

• Unit 5: Methods of studying cells
Microscopy-electron microscopy, fluorescence microscopy, confocal microscopy, live cell microscopy, Cell separation and fractionation, Cell cultures and cell lines, Cell banks

• Unit 6: Energy-Catalysis-Biosynthesis
The use of energy by cells, Cells convert energy from one form to another, The oxidation of organic molecules, How enzymes find their substrates, Activated carriers and biosynthesis-ATP, Redox reactions (NADH, NADPH)

• Unit 7: Cell membranes
The membranes of the endoplasmic reticulum, The nuclear membrane, The membranes of other organelles, Structure of the cytoplasmic membrane - The lipid bilayer and the fluid mosaic model, The role of cholesterol, Synthesis of new membranes in the endoplasmic reticulum, Membranes site of connection with the membrane, proteins Membrane pores (a helices and b leaflets), The glycocalyx- The neutrophil glycocalyx and its importance in detecting an infection, The membranous cortex-Disorders of cortical proteins- Spectrin abnormalities, Membrane regions-Diffusion barriers- Tight junctions- The importance of this structure in the generation of epithelia - The example of the intestinal epithelium

• Unit 8: Transport across cell membranes
Principles of membrane transport, Specialized carrier proteins: Carrier proteins, Passive transport, Glucose carriers and abnormalities in glucose carriers, Active transport (coupled transporters, ATP-driven pumps, light-driven pumps), The Na+/ K+ ATPase and the maintenance of osmotic balance, Protein channels-Ion channels and gating (voltage-gated, ligand-gated, mechanically gated)-Ion channels and membrane potential- How membrane potential is generated-Ion channels and signaling in nerve cells-Energe potential, How the energy potential is transferred from one cell to another-Conversion of an electrical signal into a chemical signal by neurotransmitters-The role of voltage-gated Ca+2 channels and ligand-gated ion channels of target cells , Ion channels controlled by neurotransmitters are the primary targets of psychotropic drugs

• Unit 9: Cell organelles
Non-membrane organelles: Ribosome, nucleolus, centrosome. Their main functions

• Unit 10: The Intracellular Compartments
Membrane organelles-Nucleus, Mitochondria, Peroxisomes (oxidation of toxic substances), Organelles involved in the secretory-endocytic pathway/Endoplasmic reticulum (LED: synthesis of lipids-specific proteins/AED: synthesis of proteins)/Golgi system (modification and sorting of macromolecules)/Endosomes (sorting of material after endocytosis) /Lysosomes (intracellular degradation), The origin of the nuclear membrane and mitochondria

• Unit 11: Transport between intracellular compartments
Organization and maintenance of the proteins of the compartments, Sorting and transport of proteins (protein sorting) - How the proteins synthesized in the cytoplasm reach the target organelle, How the proteins synthesized in the cytoplasm penetrate the membrane of the target organelle, Signaling sequences (for the nucleus-NLS, mitochondria, ED), Transport through nuclear pores, Transport through transporter proteins (mitochondria), Transport through transporter proteins-Peroxisomes- Zellweger disease, Transport through transporter proteins- ED, Transport from the ED to the membrane (and vice versa) and the other compartments-Transport by vesicles, Endocytosis-basic mechanisms, Clathrin-coated vesicles, How the vesicle recognizes the target membrane, The vSNARES and tSNARES proteins and the fusion of synaptic vesicles with the membrane of presynaptic neurons - vSNARES and tSNARES as targets of bacterial toxins - Botox and Tetanus, Exocytosis - control of processing and conformation of proteins that will be released, Glycosylation of proteins in ED - Mechanism, Energy-acceptable protein folding - Quality control in ED and Cystic Fibrosis, Constitutive exocytosis pathway, Regulated exocytosis pathway, Pinocytosis, Phagocytosis-Phagosome-Fusion with lysosome-Mycobacterium tuberculosis prevents fusion of phagosome with lysosome-tuberculosis, Lysosomal aggregation diseases-Gaucher, Pompe disease , Fabry, MPS I-IV, Cholesterol receptors and their uptake-Dysfunction of these receptors, hypercholesterolemia, atheromatous plaque formation, Highly pathogenic organisms use the receptor-mediated endocytosis pathway to enter the cell- HIV and AIDS

• Unit 12: Communication between cells-Signal Transduction
General principles of cell signaling - Signal transduction, Endocrine communication - Paracrine signaling - Close contact (neuronal, contact-dependent), Small molecules that cross the membrane, for example NO and the action of nitroglycerin in the treatment of acute angina, The action of Viagra, The testosterone receptor and the feminizing testis syndrome-Questions of gender identity, Large molecules that cannot cross the membrane and their receptors- intracellular signaling sequences, Receptors linked to ion channels, Receptors linked with G-proteins -Cholera, Pertussis, G-proteins that activate membrane enzymes (adenylate cyclase —responsible for the formation of cAMP, phospholipase C, responsible for the formation of inositol triphosphate and diacylglycerol) -second messengers (second messengers), The pathway of cyclic AMP activates enzymes and genes, Enzyme-linked receptors -Receptors with tyrosine kinase activity and the Ras protein, Receptors associated with tyrosine kinases JAKS, Receptors with threonine/serine kinase activity

• Unit 13: Cells get energy from food
Degradation and utilization of sugars and lipids, Glycolysis, Regulation of metabolism, The feedback mechanism

• Unit 14: Mitochondria and energy production
Cells obtain energy through a membrane-based mechanism, Mitochondria and oxidative phosphorylation, Mitochondria change shape to respond to cell functions, Cellular respiration is highly efficient

• Unit 15: Cytoskeleton
Cell fibrils-Intermediate fibrils, Keratin fibrils-Keratin gene mutations affecting the formation of intermediate fibrils-Epidermolysis vesiculi, Microtubules-Microtubules sprout from organizing centers—ketrosomes-Centrioles and their role, The centriole as an organizer of the basal body of flagella-the Meckel-Gruber syndrome (inability of proper migration of centrioles), Microtubule growth shows dynamic instability, Microtubule poisons and their applications (colchicine, taxol), Microtubules drive cell polarization, Motor proteins-Transport by length of microtubules, Actin Filaments and microvilli (intestinal fringes)/small contractile bundles in cytoplasm/transient projections (creeping fibroblast)/contractile ring (cytokinesis), Cell creep depends on cortical actin -Cell Movement, Integrins nucleate actin filaments on the intracellular side

• Unit 16: Cell cycle: Mitosis
Why do cells divide, The cell cycle of eukaryotic cells is divided into 4 phases, Mitosis is divided into 4 phases-Prophase, Metaphase, Anaphase, Telophase, The cytoskeleton performs both mitosis and cytokinesis, Cytokinesis

• Unit 17: Cell cycle regulation
Cell cycle control system-biochemical switches, Cell cycle checkpoints (molecular brakes), Cyclins and cyclin-dependent kinases-activation and deactivation of critical kinases, The G1/S checkpoint, The G2/M checkpoint and p53 protein and cancer, Cdk inhibitors (p16, p21), Centrosome cycle-chromosome cycle abnormalities, multiple centrosomes in cancer, Chromosome segregation and the mitotic spindle conformation checkpoint ( spindle assembly checkpoint-SAC)-Damage to SAC-meroterminal junctions of chromosomes, aneuploidy, lagging chromosomes, intercellular bridges, micronuclei, binucleate cells, Chromothripsis
• Unit 18: Cell cycle: Reduction
Creation of haploid gametes-One round of DNA replication, two rounds of cell division, Pairing of homologous chromosomes and crossing over, Meiosis is not infallible-Gametes with the wrong number of chromosomes-The example of trisomy 21, Mendel and the laws of inheritance, Dominant and recessive genes

• Unit 19: Cell Death-Programmed Cell Death/Apoptosis
Why is cell death important-Development-Embryogenesis-Homeostasis, Apoptosis disorders (neurodegenerative diseases, cancer), Types of cell death (Firoptosis, anoxia, mitotic catastrophe, netting, ferroptosis), Necrosis vs apoptosis, Cellular morphology of apoptosis, The role of of caspases in programmed cell death, Intrinsic pathway of apoptosis-Mitochondria, Cytochrome C, Apoptosome, Caspases, Extrinsic pathway of apoptosis-Death ligands (FasL, TNF, TRAIL), Death receptors, Caspases, TNF-initiated signaling, The family Bcl2 (pro-apoptotic and anti-apoptotic family members), Removal of apoptotic cells - Phagocytosis - Expression of special signals (eat-me signals) on the cell surface - Phosphatidylserine, Anoikis = Anoikis - loss of intercellular communication or communication with the extracellular substance , Autophagy and autophagic cell death-Related diseases

• Unit 20: Extracellular substance/Tissues-Organs
Extracellular layer and connective tissues, Diversity of connective tissues, Collagen, laminin, Genetic disorder in collagenase and pathological skin extensibility, Epithelial sheets, Epithelial cells have a polarized internal organization, Intercellular junctions- Tight junctions, Adhesion junctions, Desmosome, Gap junction, Hemi-desmosomes, Adhesion junctions, desmosome junctions and the transmembrane cadherins

• Unit 21: Disturbance of cellular homeostasis - Stem cells - Cancer
Different tissues renew themselves at different rates-Adult Stem Cells, The pattern of skin cell renewal, The price of the ability to renew and repair damage-Cancer, Cancer cells acquire properties that give them a competitive advantage

Laboratory Exercises
1. Peripheral blood centrifugation
• A. Sedimentation centrifugation
• B. Density gradient centrifugation (using Ficoll): Isolation of mononuclei and viability check with trypan blue blocking dye
2. Microscopy of blood cells
• Observation of the different types of blood cells in a photon microscope
• Classification and identification of leukocytes (lymphocytes, monocytes, eosinophils, neutrophils, basophils)
3. Determination of Blood Group
• Surface antigens of blood cells: ABO system-Rhezus system
• Determination of blood group (ABO/Rhezus)
4. Mitosis-Mitotic index
• Observation of cells in various phases of the cycle
• Identify the phases of mitosis
• Determination of mitotic index
5. Preparation of metaphase chromosomes
• Culture of peripheral blood in the presence of mitogen
• Preparation of metaphase chromosomes
Identification of metaphase chromosomes-karyotype analysis

• Lesson notes
• Basic Principles of Cell Biology, Alberts B et al. [EVDOXOS 102069992].
• Molecular Cell Biology, Lodish H et al. [EVDOXOS 122091150].

Related scientific journals:  Cell, Journal of Cell Science, Nature Reviews, Molecular Cell Biology, Nature Cell Biology, Trends in Cell Biology, Cell Research