Cell biology and technology

MARTINA PASQUA

The Cellular Microbiology and Vaccinology course aims to provide students with the knowledge and conceptual tools required to understand the complexity of interactions between microorganisms and eukaryotic organisms, with particular emphasis on the molecular mechanisms underlying host–pathogen relationships. The course introduces the fundamental principles of cellular microbiology, analysing the strategies employed by microorganisms to colonize the host, overcome defensive barriers, establish infection, and modulate host immune responses.

The teaching programme is structured in a sequential and cumulative manner, integrating knowledge of microbial recognition by the innate and adaptive immune systems, the role of the microbiota in host physiology and pathology, and the molecular mechanisms determining the transition from commensalism to pathogenicity. Particular attention is devoted to the different stages of infection, including microbial adhesion and colonization, tissue invasion, intracellular survival, evasion of host defences, and production of virulence factors responsible for cellular and tissue damage.

Through the study of selected human pathogens of medical relevance, students will explore the molecular strategies used by microorganisms to interact with host cells, alter cellular functions, and promote infection progression. The course will address gene regulatory mechanisms, host–microbe communication, secretion systems, virulence factors, adaptation to host environments, and microbial responses to the stresses imposed by the immune system.

The knowledge acquired will enable students to understand how the genetic and phenotypic characteristics of microorganisms determine different pathogenic strategies and how the balance between the host and microbial communities influences health and disease. The final part of the course will introduce the principles underlying infection prevention strategies, with particular focus on vaccines, including different vaccine platforms, the rationale behind the identification of novel vaccine targets, and the scientific and experimental pathway leading from laboratory development to clinical application.

Acquire fundamental knowledge of cellular microbiology and the complexities of interactions between the microbial world and eukaryotic organisms.
Understand the basic principles of host–microorganism interactions, the strategies employed by pathogens to initiate an infectious process, the determinants of virulence, as well as the host's defense responses and mechanisms, including the principles of reverse vaccinology.
Become familiar with the main techniques used in the study of host–pathogen interactions through the analysis of scientific articles and the methodologies applied to investigate the molecular mechanisms underlying these interactions. This will enable students to develop critical skills in analyzing data presented in scientific literature and discussed during lectures, integrating theoretical knowledge with practical competencies. These practical skills will also be developed through hands-on laboratory activities aimed at introducing students to the field of infection biology and the study of host–pathogen interactions.
Design effective experimental strategies to address complex biological questions and develop advanced problem-solving approaches in the analysis of the molecular mechanisms underlying host–pathogen interactions.

This is an advanced course that explores the interactions between microorganisms and the host, with a particular focus on the molecular and cellular mechanisms involved. A solid understanding of basic microbiology is a fundamental prerequisite. In addition, prior knowledge of innate and adaptive immunity is required, although key concepts will be reviewed and expanded upon during the lectures.
The exam consists of a reverse lesson, in which the student presents a review and a selected scientific article. This format requires the ability to independently consult scientific databases, such as PubMed, to identify relevant and up-to-date articles aligned with the topics covered in the course.

Introduction to cellular microbiology
Host-microorganism interactions with positive effects: the microbiota
Microbiota and diseases associated with dysbiosis
Host-pathogen interactions: stages of infection
Virulence factors
How bacteria sense the external environment during infection: Two-Component Systems
Efflux pumps in host-pathogen interaction
Polyamines in host-pathogen interaction
Evolution of Yersinia and the T3SS
Infection mechanisms of pathogenic Escherichia coli: EAEC and AIEC
Shigella flexneri and the response to fatty acids
Biofilm and techniques for its study and imaging
Acinetobacter baumannii
The host immune response
Vaccinology
Vaccinology: history, reverse vaccinology, techniques and future perspectives
Stages of Salmonella infection
Pseudomonas aeruginosa and stress response
New technologies for studying host-pathogen interactions: organoids
Teaching labs for the practical study of host-microorganism interaction.

Lectures will be delivered in a traditional in-person format. Practical sessions will take place in microbiology laboratories equipped for the study of interactions between microorganisms and host cells. Students will be required to wear a personal lab coat.
Occasionally, some lectures may be conducted online, particularly for seminars given by international guests or due to specific needs of the professor.

Attendance is not mandatory, but strongly recommended for a better understanding of theoretical and practical content.

Oral exam aimed at assessing the knowledge acquired during the course.
The student will be asked to answer questions on topics covered during the lectures, such as:
• the stages of the invasive process of a pathogen;
• the definition and examples of virulence factors;
• examples of pathogens that use zipper and trigger mechanisms to invade host cells.
In addition, the student is required to present a paper based on a scientific article of their choice, previously approved by the instructor, and to answer any related questions.

- Reverse lesson: consists of a presentation of no more than 20 minutes on a review article (used to introduce the topic) and a scientific paper chosen by the student and approved by the Professor. The selection of the article is part of the assessment, as the topic must be relevant to the themes covered in class.

- Questions about the presentation: clarifications and insights regarding the scientific article presented by the student.

- Questions on topics covered in class. For example:
-Difference between the zipper and trigger mechanisms. Examples of pathogenic bacteria that use the two mechanisms.
-What the adhesion mechanism consists of.
-Virulence factors.
-Invasion mechanism of the pathogen Shigella.
-Survival mechanism of Salmonella within macrophages.
-Examples of immune evasion.
-Biofilm: what it is and how it is studied.