Cellular Microbiology and Immunology
A.Y. 2025/2026
Learning objectives
At the end of this course the students will have a good knowledge of the main host-pathogen interaction mechanisms. The course addresses the concepts of bacterial virulence and pathogenicity, starting from the differences between eukaryotic and prokaryotic cellular structures, focusing on the microbial metabolism and microbial genetics, and moving to the concepts of infectious disease or foodborne diseases.
During the course we will debate the main components of the innate and adaptive immune system involved in the pathogen recognition and clearance, focusing on the main immune-escape mechanisms, and the establishment of chronic infection and inflammation.
In addition, the course will analyze the critical role that microbiota plays in human metabolism (composition and bacterial function) and health (immunological functions, promotion of intestinal homeostasis). Finally, we will further analyze the concept of dysbiosis and the Gut-brain axis, as well as, the ways in which the microbial community is perturbed in dysbiotic disease states.
During the course we will debate the main components of the innate and adaptive immune system involved in the pathogen recognition and clearance, focusing on the main immune-escape mechanisms, and the establishment of chronic infection and inflammation.
In addition, the course will analyze the critical role that microbiota plays in human metabolism (composition and bacterial function) and health (immunological functions, promotion of intestinal homeostasis). Finally, we will further analyze the concept of dysbiosis and the Gut-brain axis, as well as, the ways in which the microbial community is perturbed in dysbiotic disease states.
Expected learning outcomes
At the end of the course, students will be able to describe the differences between commensal bacteria and pathogens, to understand the mechanisms of bacterial pathogenicity. In addition, students will be able to describe the role and function of the main components of innate and adaptive immune system, and to define the main mechanisms of host-pathogen interaction. Finally, students will have acquired a solid knowledge on the different pathogenic diseases caused by an altered immune response, the main evasion strategies used by pathogens to escape the immune system, and will be able to identify the most appropriate prevention or treatment strategies.
Lesson period: First semester
Assessment methods: Esame
Assessment result: voto verbalizzato in trentesimi
Single course
This course can be attended as a single course.
Course syllabus and organization
Single session
Responsible
Lesson period
First semester
Course syllabus
Microorganisms: bacterial classification and taxonomy, definition of virulence factors and pathogenicity. Infectious diseases and foodborne illnesses: pathogenicity and virulence factors, bacterial toxins and their mechanisms of action.
Innate immunity: physical and chemical barriers. Main functions of epithelial cells and antimicrobial peptides. Professional phagocytes: activation and function of macrophages and neutrophils, cellular and molecular processes of phagocytosis and NETs formation. Natural killer cells and the complement system: activation, cooperation, and strategies in the host defense against pathogenic bacteria. Innate Lymphoid Cells (ILCs): classification, functions in mucosal defense and maintenance of tissue homeostasis.
Evasion strategies of pathogenic bacteria against the components of the innate immune system.
Antigen presentation: antigen-presenting cells (APCs), dendritic cells, major histocompatibility complex (MHC-I and MHC-II). Strategies of antigen presentation inhibition by pathogenic bacteria, and modulation of immunogenicity.
Adaptive immunity: CD8 and CD4 T lymphocytes. Differentiation, activation, and role of CD8 T lymphocytes (CTLs) in the defense against intracellular bacteria. Evasion strategies of intracellular pathogens from cell-mediated immunity. Differentiation, activation, and role of the CD4+ T cell subsets (Th1, Th2, Th17, Th1/17, Th9, Treg) in the host defense. Dysregulation of the adaptive immune response in autoimmune diseases. Microbial immunomodulatory strategies targeting CD4+ T lymphocytes: inhibition/hyperactivation of TCR signaling, induction of Treg cells, interference with CD4 T helper polarization.
The microbiota: composition, phyla, nomenclature, enterotypes, and distribution across different anatomical sites. Microbiota functions: metabolic, structural, protective, and immunological. The microbiota as a regulator of immune responses: cross-talk with cells of the innate and adaptive immune system. Microbiome research in biomedical science: NGS (Next Generation Sequencing) technologies, omics technologies (metagenomics and metatranscriptomics), third-generation sequencing technologies, main databases.
Dysbiosis: definition, causes, and evasion strategies of pathogenic microorganisms against the protective and immunological functions of the microbiota. Impact on chronic and immune-mediated diseases. Microbiota-based therapeutic interventions: prebiotics, probiotics, postbiotics, and engineered probiotics; mechanisms of action and immunomodulatory potential. Microbiota as a target for personalized therapies: new perspectives in the management of dysbiosis-associated diseases.
Gut-Brain Axis and Gut-Lung Axis: bidirectional communication between the intestinal microbiota and the central nervous system or respiratory tract; molecular and cellular mechanisms in neurodegenerative diseases.
Classical vaccinology and reverse vaccinology: nature of antigens, ability of antigens to activate innate and adaptive immune responses, mRNA platforms, genomic approaches to vaccine design, recombinant proteins, viral vectors, induction of immune memory.
During the laboratory sessions, the adhesion and persistence capabilities of bacterial strains of different origins will be assessed on intestinal or pulmonary epithelial cell lines, in order to investigate the dynamics of host-pathogen interactions. In addition, the inflammatory response of infected epithelial cells will be analyzed using ELISA assays, with the aim of evaluating the production of pro-inflammatory molecules following interaction with pathogenic bacteria.
Innate immunity: physical and chemical barriers. Main functions of epithelial cells and antimicrobial peptides. Professional phagocytes: activation and function of macrophages and neutrophils, cellular and molecular processes of phagocytosis and NETs formation. Natural killer cells and the complement system: activation, cooperation, and strategies in the host defense against pathogenic bacteria. Innate Lymphoid Cells (ILCs): classification, functions in mucosal defense and maintenance of tissue homeostasis.
Evasion strategies of pathogenic bacteria against the components of the innate immune system.
Antigen presentation: antigen-presenting cells (APCs), dendritic cells, major histocompatibility complex (MHC-I and MHC-II). Strategies of antigen presentation inhibition by pathogenic bacteria, and modulation of immunogenicity.
Adaptive immunity: CD8 and CD4 T lymphocytes. Differentiation, activation, and role of CD8 T lymphocytes (CTLs) in the defense against intracellular bacteria. Evasion strategies of intracellular pathogens from cell-mediated immunity. Differentiation, activation, and role of the CD4+ T cell subsets (Th1, Th2, Th17, Th1/17, Th9, Treg) in the host defense. Dysregulation of the adaptive immune response in autoimmune diseases. Microbial immunomodulatory strategies targeting CD4+ T lymphocytes: inhibition/hyperactivation of TCR signaling, induction of Treg cells, interference with CD4 T helper polarization.
The microbiota: composition, phyla, nomenclature, enterotypes, and distribution across different anatomical sites. Microbiota functions: metabolic, structural, protective, and immunological. The microbiota as a regulator of immune responses: cross-talk with cells of the innate and adaptive immune system. Microbiome research in biomedical science: NGS (Next Generation Sequencing) technologies, omics technologies (metagenomics and metatranscriptomics), third-generation sequencing technologies, main databases.
Dysbiosis: definition, causes, and evasion strategies of pathogenic microorganisms against the protective and immunological functions of the microbiota. Impact on chronic and immune-mediated diseases. Microbiota-based therapeutic interventions: prebiotics, probiotics, postbiotics, and engineered probiotics; mechanisms of action and immunomodulatory potential. Microbiota as a target for personalized therapies: new perspectives in the management of dysbiosis-associated diseases.
Gut-Brain Axis and Gut-Lung Axis: bidirectional communication between the intestinal microbiota and the central nervous system or respiratory tract; molecular and cellular mechanisms in neurodegenerative diseases.
Classical vaccinology and reverse vaccinology: nature of antigens, ability of antigens to activate innate and adaptive immune responses, mRNA platforms, genomic approaches to vaccine design, recombinant proteins, viral vectors, induction of immune memory.
During the laboratory sessions, the adhesion and persistence capabilities of bacterial strains of different origins will be assessed on intestinal or pulmonary epithelial cell lines, in order to investigate the dynamics of host-pathogen interactions. In addition, the inflammatory response of infected epithelial cells will be analyzed using ELISA assays, with the aim of evaluating the production of pro-inflammatory molecules following interaction with pathogenic bacteria.
Prerequisites for admission
Basic knowledge of microbiology is required.
Teaching methods
The teaching activities are structured in two parts: a first part consisting of interactive frontal lectures (5 CFU), supported by projected teaching materials, and a second part consisting of practical laboratory sessions (1 CFU). During practical laboratory activities, students will actively take part in the experiments related to host-pathogen interactions, applying selected theorethical concepts acquired during the lectures.
Attendance is strongly recommended, as active participation in both theoretical lectures and practical activities is considered essential for the development and consolidation of students' critical thinking, analytical skills, and scientific reasoning.
The teaching material will be made available to the students through the dedicated ARIEL website.
Attendance is strongly recommended, as active participation in both theoretical lectures and practical activities is considered essential for the development and consolidation of students' critical thinking, analytical skills, and scientific reasoning.
The teaching material will be made available to the students through the dedicated ARIEL website.
Teaching Resources
To support the acquisition and consolidation of foundational knowledge, the following textbooks may be used as general references:
· Principi di microbiologia medica (Antonelli - Clementi - Pozzi - Rossolini)
· Microbiologia generale (Prescott)
· Immunologia cellulare e molecolare (Abbas - Lichtman - Pillai)
All teaching materials presented during the lectures will be made available in PDF format on the dedicated Ariel platform. In addition, a selection of scientific articles will be provided to students as supplementary resources for further study and in-depth exploration of the topics covered in class.
· Principi di microbiologia medica (Antonelli - Clementi - Pozzi - Rossolini)
· Microbiologia generale (Prescott)
· Immunologia cellulare e molecolare (Abbas - Lichtman - Pillai)
All teaching materials presented during the lectures will be made available in PDF format on the dedicated Ariel platform. In addition, a selection of scientific articles will be provided to students as supplementary resources for further study and in-depth exploration of the topics covered in class.
Assessment methods and Criteria
The acquisition of knowledge and the achievement of the expected learning outcomes are verified through an oral test structured in two parts, with distinct modalities for attending and non-attending students.
For attending students, the first part consists of an oral discussion focused on the critical analysis and scientific interpretation of experimental data obtained during laboratory practical sessions. This component is intended to foster scientific reasoning and promote independent critical thinking.
For non-attending students, the first part consist of a PowerPoint presentation and discussion of a scientific article, selected from a list provided by the professor, on a topic relevant to the course content.
This first part contributes to 20% of the overall final grade.
The second part, common to both attending and non-attending students, is intended to provide an in-depth assessment of the following aspects:
· the knowledge acquired in cellular microbiology, with specific focus on the cellular and molecular mechanisms underlying microbial virulence and pathogenicity;
· the understanding of immunological processes, including the activation mechanisms of the innate and adaptive immune system in response to both commensal and pathogenic microorganisms (bacteria and viruses).
This second part accounts for 80% of the final evaluation.
The final grade will be determined based on the accuracy and completeness of the content, and, in particular, on the scientific coherence and argumentative clarity in the presentation of the topics.
The final score will be expressed on a 30-point scale (30/30).
The second part aims to evaluate both the competencies of cellular microbiology, in particular on bacterial virulence and pathogenesis, as well as the competencies concerning the interactions of pathogens (bacteria and virus) with the immune system (contribution of 85% to the final evaluation).
The assessment will also take into account the ability to discuss and comment with a correct scientific language. The final grade is expressed in 30/30. The examination procedures are the same for attending and non-attending students.
For attending students, the first part consists of an oral discussion focused on the critical analysis and scientific interpretation of experimental data obtained during laboratory practical sessions. This component is intended to foster scientific reasoning and promote independent critical thinking.
For non-attending students, the first part consist of a PowerPoint presentation and discussion of a scientific article, selected from a list provided by the professor, on a topic relevant to the course content.
This first part contributes to 20% of the overall final grade.
The second part, common to both attending and non-attending students, is intended to provide an in-depth assessment of the following aspects:
· the knowledge acquired in cellular microbiology, with specific focus on the cellular and molecular mechanisms underlying microbial virulence and pathogenicity;
· the understanding of immunological processes, including the activation mechanisms of the innate and adaptive immune system in response to both commensal and pathogenic microorganisms (bacteria and viruses).
This second part accounts for 80% of the final evaluation.
The final grade will be determined based on the accuracy and completeness of the content, and, in particular, on the scientific coherence and argumentative clarity in the presentation of the topics.
The final score will be expressed on a 30-point scale (30/30).
The second part aims to evaluate both the competencies of cellular microbiology, in particular on bacterial virulence and pathogenesis, as well as the competencies concerning the interactions of pathogens (bacteria and virus) with the immune system (contribution of 85% to the final evaluation).
The assessment will also take into account the ability to discuss and comment with a correct scientific language. The final grade is expressed in 30/30. The examination procedures are the same for attending and non-attending students.
BIO/19 - MICROBIOLOGY - University credits: 6
Practicals: 16 hours
Lessons: 40 hours
Lessons: 40 hours
Professor:
Paroni Moira
Professor(s)
Reception:
10am-12pm (by email appointment)
Department of Biosciences (Scientific Buildings) - 1st floor Tower B