Journal of Research in Microbiology and Immunology ISSN: 3108-0952 (Online)

Authors: Pankaj Gehlot, S. K. Chauhan

Abstract: This paper delves into the intricate world of microbial genetics, providing a comprehensive understanding of how genetic information in microbes influences their functioning, adaptation, and evolutionary processes. Through an in-depth analysis of plasmids, horizontal gene transfer (HGT), and genetic engineering, this study highlights the dynamic and complex nature of microbial genetics. Utilizing a combination of literature review, experimental data analysis, and case studies, the research uncovers new insights into the mechanisms of genetic variation and adaptation in microbial populations. Key findings reveal a significant influence of HGT in microbial evolution and the adaptive potential facilitated through plasmids and genetic engineering techniques. The conclusions drawn from this study not only contribute to the broader scientific understanding of microbial genetics but also pave the way for future research and applications in biotechnology, medicine, and environmental science.

Keywords:  Microbial Genetics, Genetic Information, Adaptation, Evolution, Plasmids, Horizontal Gene Transfer, Genetic Engineering

Authors: Dr. Kapil Sharma, Ayush Kumar, Kalesh Mehra

Abstract: This paper examines the pivotal role of microorganisms in environmental processes, focusing on their impact in soil and water ecosystems, their contribution to bioremediation efforts, and their influence on climate change. Utilizing a comprehensive review of current literature combined with empirical data analysis, this study aims to enhance our understanding of the integral role played by microbes in ecological balance and environmental health. Key findings underscore the diverse functions of microbial communities in various ecosystems, their capability to degrade pollutants through bioremediation, and their significant yet often overlooked contribution to climate dynamics. The research underscores the need for a deeper appreciation of microbial activities in environmental management and policy-making, highlighting how these tiny organisms significantly influence larger ecological and climatic processes.

Keywords: Environmental Microbiology, Ecosystems, Soil Microbiology, Water Microbiology, Contribution

Authors: Dhiraj Malhotra, Payal Gupta

Abstract: This study focuses on unraveling the molecular mechanisms underlying antibiotic resistance in Staphylococcus aureus, a significant causative agent of both hospital- and community-acquired infections. Given the alarming rise in antibiotic-resistant strains of S. aureus, including MRSA (Methicillin Resistant Staphylococcus aureus), understanding these mechanisms are crucial for developing effective treatment strategies. We employed a combination of microbiological and molecular biology techniques to examine the resistance patterns and underlying genetic and biochemical factors in various S. aureus strains. Our methods included antibiotic susceptibility testing, PCR amplification, and sequencing of key resistance genes. The study revealed diverse resistance profiles and identified specific genetic mutations associated with resistance to several commonly used antibiotics. These findings provide insights into the adaptive strategies of S. aureus and highlight potential targets for novel therapeutic interventions. The study underscores the need for continued research into bacterial resistance mechanisms to inform the development of effective and sustainable treatment strategies against S. aureus infections.

Keywords: - Staphylococcus aureus, Antibiotic Resistance, Molecular Mechanisms, Treatment Strategies, Bacterial Pathogenesis

Authors: Kajal Desai, Abhimanyu Kanojiya, Preeti Mehto

Abstract: The immune system plays a vital role in defending the body against pathogens and maintaining homeostasis. Immune responses involve a sophisticated network of immune cells that communicate and coordinate their activities through intricate signaling pathways. Understanding the mechanisms of immune cell signaling and regulation is essential for unraveling the complexities of immune responses. This paper aims to provide an overview of the key signaling pathways involved in immune cell communication and the regulatory mechanisms that fine-tune immune responses. We will explore the roles of major immune cell types, including lymphocytes, macrophages, dendritic cells, and innate immune cells, in mounting effective immune responses. Additionally, we will discuss the influence of various factors such as cytokines, chemokines, and antigen presentation on immune cell signaling and regulation. By shedding light on the intricate interplay between immune cells and their signaling networks, this paper aims to deepen our understanding of immune responses and potentially inform the development of novel therapeutic strategies.

Keywords: Immune system, Cytokines, Lymphocytes, Cytokine-mediated signaling, Therapeutic strategies, Toll-like receptors, Dendritic cells, Antigen presentation

Authors: Dr. Pawandeep Bhalla, Ashok Gupta

Abstract: Microbial pathogenesis is a complex process involving the interplay between pathogenic microorganisms and their host organisms. Understanding the molecular mechanisms underlying microbial pathogenesis is crucial for the development of effective therapeutic strategies. This paper provides an overview of the key concepts and recent advances in the field of microbial pathogenesis, focusing on the identification and characterization of virulence factors and the intricate host-microbe interactions that shape disease outcomes. We highlight the importance of unraveling these molecular mechanisms for the development of targeted interventions to combat infectious diseases.

Keywords: microbial pathogenesis, virulence factors, host-pathogen interactions, adhesion, invasion, toxins, secretion systems, immune evasion, innate immune response, adaptive immune response.

Authors: Shobha Kashyap, Rukmani Devi

Abstract: The human immune system is a remarkable network of cells, molecules, and tissues that work together to protect the body from infectious agents and maintain overall health. It consists of two primary components: innate immunity and adaptive immunity. While the innate immune response provides rapid, nonspecific defense mechanisms, the adaptive immune response offers a tailored, specific defense against pathogens. This paper aims to explore the interplay between innate and adaptive immunity, highlighting their respective roles and the coordination required for effective protection. We will discuss the mechanisms of recognition, activation, and effector functions of both immune responses, emphasizing their synergistic nature in mounting robust and targeted immune responses. Understanding the dynamic relationship between innate and adaptive immunity is crucial for the development of novel immunotherapeutic strategies and vaccines, ultimately leading to improved protection against infectious diseases and other immunological disorders.

Keywords: human immune system, innate immunity and adaptive immunity, immunotherapeutic strategie, immunological disorders

Authors: Swati Maheshwari, Ajay Kumar Meena, Karan Pawar

Abstract: The human gut harbors a complex and diverse microbial community known as the gut microbiota. Recent research has shed light on the crucial role of the gut microbiota in modulating immune responses and maintaining overall health. This paper aims to explore the intricate relationship between the gut microbiota, immunomodulation, and its implications in the development and progression of various diseases. We discuss the mechanisms through which gut microbiota interacts with the host immune system, the impact of dysbiosis on immune homeostasis, and the association between gut microbiota and immune-related disorders such as inflammatory bowel disease, allergies, and autoimmune conditions. Furthermore, we highlight emerging therapeutic strategies that target the gut microbiota for the modulation of immune responses and disease management. Overall, understanding the interplay between the gut microbiota and the immune system has the potential to revolutionize our approach to disease prevention, diagnosis, and treatment.

Keywords: Gut microbiota, Fecal microbiota transplantation (FMT), Cytokines, Inflammatory bowel disease (IBD), Metabolic disorders, Antimicrobials, Allergic diseases

Authors: Piyush Garhawal, Ravinder Pathak

Abstract: Antimicrobial resistance (AMR) poses a significant global health threat, rendering traditional antimicrobial drugs less effective against various pathogens. This paper aims to explore the challenges associated with AMR and propose strategies to combat drug-resistant pathogens. The challenges include overuse and misuse of antimicrobials, inadequate infection prevention and control measures, limited development of new antibiotics, and the complex nature of AMR. Strategies to address these challenges involve public awareness and education, strengthening infection prevention and control, rational use of antimicrobials, development of new antibiotics and alternatives, and international collaboration. A comprehensive approach that integrates these strategies is crucial to mitigate the impact of AMR and preserve the efficacy of antimicrobial drugs.

Keywords: Antimicrobial resistance, AMR, Healthcare providers, Prudent antimicrobial use, Multidisciplinary collaboration, Economic incentives

Authors: Dr. Priya Nair, Dr. Arjun Mehta

ABSTRACT: The advent of mRNA vaccine technology has revolutionized the field of immunization, offering rapid, flexible, and highly effective solutions against infectious diseases. Unlike traditional vaccines, mRNA vaccines utilize a synthetic messenger RNA to instruct host cells to produce specific antigens, eliciting robust humoral and cellular immune responses. This paper explores the development of next-generation mRNA vaccines, detailing design strategies, delivery platforms, immunogenicity optimization, and safety considerations. Emphasis is placed on current applications in combating viral pathogens, such as SARS-CoV-2, and the potential extension to bacterial, parasitic, and oncological targets. Challenges including stability, storage, and distribution are discussed alongside innovative solutions like lipid nanoparticles, self-amplifying mRNA, and thermostable formulations. Tables summarizing mRNA vaccine platforms, delivery methods, and clinical outcomes are provided. Understanding mRNA vaccine design principles and translational strategies can guide future vaccine development, enhancing global preparedness against emerging infectious diseases.

KEYWORDS: mRNA vaccines, Next-generation vaccines, Lipid nanoparticles, Self-amplifying RNA, Immunogenicity, SARS-CoV-2, Vaccine delivery

Authors: Dr. Meera Nair, Dr. Aditya Verma

ABSTRACT: Autoimmune diseases, characterized by dysregulated immune responses against self-antigens, remain a significant clinical challenge. Emerging evidence highlights the pivotal role of the gut microbiome in shaping immune homeostasis, influencing the onset and progression of autoimmune disorders. Microbiome modulation using probiotics, prebiotics, dietary interventions, and fecal microbiota transplantation (FMT) has gained attention as an adjunct therapy. This paper explores the mechanisms by which microbiota influence autoimmunity, summarizes current therapeutic strategies for microbiome modulation, and discusses immunological outcomes. Tables highlighting key autoimmune diseases, microbiome alterations, and therapeutic interventions are included. Understanding microbiome-immune system interactions provides novel insights into adjunctive therapies that may enhance conventional treatment efficacy, reduce adverse effects, and improve patient outcomes.

KEYWORDS: Microbiome, Autoimmune diseases, Probiotics, Prebiotics, Fecal microbiota transplantation, Immune modulation, Adjunct therapy

Authors: Dr. Ananya Sharma, Dr. Rohan Mehta

ABSTRACT: Immune tolerance in organ transplantation is a complex and critical process that determines the long-term success of graft survival. Despite advances in immunosuppressive therapies, graft rejection remains a major challenge. Immune tolerance refers to the ability of the recipient's immune system to accept a transplanted organ without eliciting a destructive immune response. This paper reviews the cellular and molecular mechanisms that underlie immune tolerance, including central and peripheral tolerance, regulatory T cells, co-stimulatory blockade, and tolerogenic dendritic cells. Emphasis is placed on experimental and clinical strategies that aim to induce tolerance, thereby reducing dependency on lifelong immunosuppressive drugs. The review also discusses emerging biomarkers for tolerance and potential therapeutic approaches. Understanding these mechanisms is essential for developing targeted interventions that enhance graft survival, minimize rejection, and improve overall patient outcomes.

KEYWORDS: Immune tolerance, organ transplantation, regulatory T cells, dendritic cells, graft survival, co-stimulatory blockade.

Authors: Dr. Meera Sharma, Dr. Arjun Patel

ABSTRACT: Oxidative stress, characterized by the imbalance between reactive oxygen species (ROS) production and antioxidant defenses, is a critical factor in the pathogenesis of infectious diseases. Excess ROS can damage cellular components, impair immune cell function, and exacerbate inflammatory responses, leading to immune dysfunction. This review examines the molecular mechanisms linking oxidative stress to immune impairment during bacterial, viral, and parasitic infections. Key pathways include modulation of innate and adaptive immune responses, cytokine dysregulation, and oxidative damage to immune effector cells. Therapeutic strategies targeting redox balance, including antioxidants and pharmacological modulators, are discussed. Understanding the interplay between oxidative stress and immune dysfunction provides opportunities for novel adjunctive therapies to improve host defense and clinical outcomes in infectious diseases.

KEYWORDS: Oxidative stress, immune dysfunction, reactive oxygen species, infections, antioxidants, redox imbalance, immune modulation.

Authors: Dr. Priyanka Sharma, Dr. Rahul Kapoor

ABSTRACT: Climate change is increasingly recognized as a major driver of emerging microbial diseases, influencing pathogen distribution, transmission dynamics, and host susceptibility. Rising global temperatures, altered precipitation patterns, and extreme weather events impact microbial ecology, vector populations, and human-animal-environment interactions, leading to increased incidence of infectious diseases. This paper reviews the mechanisms linking climate change to microbial disease emergence, including effects on pathogen survival, vector ecology, and zoonotic spillover. Tables summarizing climate-sensitive pathogens, their vectors, and geographic expansion are included. Strategies for surveillance, early warning systems, and adaptation in public health are discussed. Understanding the interplay between climate change and microbial dynamics is essential for developing proactive interventions to mitigate emerging infectious disease risks.

KEYWORDS: Climate change, Microbial disease emergence, Vector-borne diseases, Zoonoses, Pathogen ecology, Public health, Adaptation strategies

Authors: Dr.Suresh Chandra Nayak , Rahul Choudhary

Abstract: Immune system disorders cause abnormally low activity or over activity of the immune system. In cases of immune system over activity, the body attacks and damages its own tissues (autoimmune diseases). Immune deficiency diseases decrease the body's ability to fight invaders, causing vulnerability to infections. Some of the autoimmune disease are as follows rheumatoid arthritis, systemic lupus erythematosus (lupus), inflammatory bowel disease (IBD),multiple sclerosis (MS),Type 1 diabetes mellitus, Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy, psoriasis.

Keywords: Autoimmune Diseases, IBD, Lupus, Immune System

Authors: Himanshu Raj, Sanjiv Kumar

Abstract: The wound infections caused by bacteria and fungi are a significant problem in healthcare. Therefore, an effective treatment and prevention seems to be essential. Povidone-iodine is one of the commercial antimicrobial agents used for skin disinfection, in surgery and for local anti-infective treatment. The broad activity spectrum of this compound includes numerous species of Gram positive and Gram- negative bacteria, mycobacteria, fungi, protozoa and viruses. Povidone-iodine is recommended for acute wounds as well as lacerations, bruises and deep wounds due to its good tissue penetration.

Keywords: Povidone-iodine, PVP-I, Antiseptic, Antimicrobial, Wound infection.

Authors: Grish Sharma, Abhishek Gautam

Abstract: Esomeprazole is a proton pump inhibitor and BCS 11 chemical used to treat gastric and duodenal ulcers. The medication has a half-life of 4 hours. In acidic stomach conditions, the medication has low stability. As a result, it is formed into compact and effective carriers known as microspheres. Bioadhesive properties can be combined to create mucoadhesive microspheres with increased residence duration. Mucoadhesive microspheres are widely used in targeted drug delivery because of their advantages such as efficient absorption and improved bioavailability of drugs, as well as a much more intimate contact with the mucus layer, controlled and sustained release of drug from dosage form, and precise targeting of drugs to the absorption site. Enteric polymer coating will aid in the targeting of therapeutic activity in the gut, particularly in the ileum area. Microspheres in regular tablets have drawbacks, such as the requirement for frequent administration. Osmotic tablets will offer medication release independent of pH, but will incur the cost of complex laser drilling. The major benefits of a controlled porosity osmotic pump (CPOP) include reduced stomach discomfort and the absence of expensive laser-drilling processes.

Keywords: Controlled drug delivery, microspheres, muco-adhesion, osmotic system, esomeprazole

Authors: Anuj Rai, Akansha Singh, Pranjali Thakur

Abstract: Silver nanoparticles are now widely considered as the industry's cornerstone. Silver, its compounds, and related salts have been around since the dawn of time. Although silver has long been known, it was only recently that the production of silver nanoparticles became a reality. It has several important uses in medicine, agriculture, and other industries. It has strong antioxidant, antibacterial, and antifungal properties. It is effective against a wide range of bacteria, including Vibrio parahaemolyticus, Citrobacter koseri, Salmonella Typhii, Pseudomonas aeruginosa, and Staphylococcus aureus, as well as a few fungi, including Candida albicans. The interaction of silver ions with biomolecules found in cells might be the cause of the process. The entire system is assumed to work on the fact that it causes the formation of free radicals as well as the generation of ROS (reactive oxygen species), which finally results in an apoptotic scenario and therefore the cell's inability to reproduce. Food preservation and cosmetics are two examples of uses. However, physical and chemical Ag production has failed to fulfil demand while causing severe environmental harm. As a result, a more efficient, ecologically friendly, and cleaner method is necessary. The biosynthesis of Ag nanoparticles from plants, algae, and bacteria, among other things, has explored this topic. This review considers similar attempts in recent years.

Keywords: Silver nanoparticles; Algae; Bacteria; Fungi; Green synthesis; Toxicity mechanism.

Authors: Swastik Kumar, Ved Prakash, Raj Kumar

Abstract: The immune system is critical to the organism's protection. The immune system's effects, however, are not restricted to immunological activities and have implications beyond the anti-pathogen role. Indeed, neuroimmunology is a science that studies how the immune system influences non-immune biological and physiopathological activities. To provide light on this vital topic, we have chosen a variety of neurodegenerative disorders as illustrative cases. Clarifying the links and interactions between the immune system and the nervous system is important for understanding neurodegenerative diseases because it will lead to new theories about pathogenesis and the mechanisms underlying the related processes, providing us with new data and novel tools to both describe the related pathways and develop new therapeutic approaches, diagnostic approaches, and research methodologies.

Keywords: Alzheimer's Disease Multiple Sclerosis Myasthenia Gravis Neurodegenerative Diseases Neuroimmunology Opsoclonus-Myoclonus Syndrome

Authors: Dr. Meera Kapoor, Dr. Rohan Mehta

ABSTRACT: Antimicrobial resistance (AMR) represents one of the most pressing global health crises of the 21st century. This phenomenon not only reduces the efficacy of antibiotic treatments but also disrupts the delicate interplay between the human immune system and microbial populations. Both innate and adaptive immune responses are deeply affected by AMR, altering host pathogen dynamics, immune recognition, and inflammatory pathways. This paper explores the immunological consequences of AMR by examining its influence on innate immune mechanisms such as phagocytosis, complement activation, and pattern recognition, as well as on adaptive immune memory and antibody generation. Furthermore, emerging findings reveal that resistant bacterial strains can evade immune detection and prolong infections, leading to chronic inflammation and increased mortality. Understanding the molecular basis of these interactions is essential for developing next generation antimicrobial strategies that enhance immune resilience while minimizing resistance development.

KEYWORDS: Antimicrobial Resistance, Innate Immunity, Adaptive Immunity, Immune Evasion, Pathogen Interaction

Authors: Dr. Neha Sharma, Dr. Rohan Desai

ABSTRACT: CRISPR-Cas systems represent a groundbreaking discovery in molecular biology and microbiology, providing insights into bacterial adaptive immunity and paving the way for revolutionary biomedical technologies. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR associated (Cas) proteins enable prokaryotic organisms to identify and destroy foreign genetic material, such as bacteriophages and plasmids. This RNA-guided defense system, first observed as peculiar DNA repeats in bacteria, now forms the foundation for modern genome-editing technologies. CRISPR-Cas systems are classified into two primary classes based on structural and functional diversity, with Cas9, Cas12, and Cas13 emerging as the most studied enzymes. Beyond natural bacterial defense, CRISPR has been re-engineered for biomedical applications including genome editing, gene regulation, diagnostics, and antimicrobial therapies. This paper explores the mechanisms of bacterial immunity via CRISPR-Cas systems, their structural diversity, and transformative roles in modern biotechnology and medicine.

KEYWORDS: CRISPR-Cas, Genome editing, Bacterial immunity, Gene therapy, Biomedical applications

Authors: Dr. Nisha Patil, Dr. Arjun Mehra

ABSTRACT: Neglected tropical diseases (NTDs) affect over one billion people worldwide, predominantly in low- and middle-income countries. Despite their substantial morbidity and socioeconomic impact, vaccine development for NTDs has lagged due to scientific, economic, and logistical challenges. This paper reviews the current landscape of vaccines for major NTDs, including leishmaniasis, schistosomiasis, lymphatic filariasis, and Chagas disease. Limitations such as antigenic variability, complex life cycles, low commercial incentives, and inadequate clinical trial infrastructure are discussed. Emerging vaccine platforms, including recombinant protein vaccines, viral vectors, and mRNA-based vaccines, are evaluated for their potential to overcome existing barriers. The review also emphasizes strategies to enhance vaccine efficacy, safety, and accessibility. Understanding the limitations and prospects of NTD vaccines is essential to accelerate their development and implementation, ultimately reducing the global burden of these diseases.

KEYWORDS: Neglected tropical diseases, vaccines, leishmaniasis, schistosomiasis, Chagas disease, vaccine platforms, global health.

Authors: Dr. Meera Sharma, Rahul Verma

ABSTRACT: The gut microbiota, a complex community of microorganisms residing in the human gastrointestinal tract, plays an essential role in shaping the host immune system. This paper explores the intricate relationship between gut microbiota composition and immune modulation, focusing on how microbial metabolites and host–microbe interactions govern immune tolerance, inflammation, and disease susceptibility. Recent research has illuminated how dysbiosis — an imbalance in gut microbial composition — contributes to autoimmune and inflammatory conditions. The microbiota influences both innate and adaptive immunity through molecular signaling involving short chain fatty acids, microbial antigens, and cytokine regulation. Understanding this dynamic interplay provides valuable insights into therapeutic approaches such as probiotics, prebiotics, and fecal microbiota transplantation (FMT). This study emphasizes the necessity of maintaining microbial balance to ensure immune homeostasis and highlights emerging directions for clinical intervention in immune-related disorders. 

KEYWORDS: Gut Microbiota, Immune Modulation, Dysbiosis, Short-Chain Fatty Acids, Immunotherapy.

Authors: Dr. Radhika Mehra, Dr. Arjun Kapoor

ABSTRACT: The human immune system is a highly complex defense network designed to identify and neutralize invading microorganisms. However, many pathogens have evolved sophisticated strategies to circumvent immune detection and destruction. Immune evasion mechanisms enable bacteria and viruses to persist within hosts, cause chronic infections, and spread effectively. These mechanisms involve molecular mimicry, antigenic variation, suppression of immune signaling, and direct interference with immune effector functions. Bacteria employ tactics such as biofilm formation, capsule production, and secretion of virulence factors that inhibit phagocytosis and complement activation. Viruses, on the other hand, utilize methods like antigenic drift, latency, inhibition of interferon pathways, and modulation of major histocompatibility complex (MHC) expression. Understanding these evasion strategies is critical to designing advanced vaccines and immunotherapeutics that can effectively counter adaptive pathogens. This paper explores the multifaceted immune evasion mechanisms in pathogenic bacteria and viruses, providing insight into their clinical significance and potential therapeutic interventions.

KEYWORDS: Immune evasion, Antigenic variation, Pathogenic bacteria, Viral latency, Immune modulation

Authors: Dr. Ananya Mehta, Dr. Rohit Singh

Abstract: Infectious diseases continue to pose significant global health challenges, driving the search for novel therapeutic strategies. Herbal immunomodulators, derived from traditional medicinal plants, offer a promising adjunct or alternative to conventional therapies by enhancing host immune responses. This review focuses on key herbal immunomodulators, including Echinacea, Withania somnifera, Tinospora cordifolia, and Curcuma longa, analyzing their mechanisms of action, preclinical and clinical efficacy, and potential integration into infectious disease management. Emphasis is placed on modulation of innate and adaptive immunity, cytokine regulation, and antioxidant properties. Tables summarize representative herbal agents, immunological effects, and evidence from studies. Challenges such as standardization, bioavailability, and safety are discussed. The paper highlights the potential of herbal immunomodulators to complement conventional therapies, improve disease outcomes, and provide a sustainable strategy for infectious disease control.

Keywords: Herbal immunomodulators, infectious diseases, immune modulation, cytokines, Echinacea, Tinospora cordifolia, Withania somnifera.

Authors: Dr. Sneha Kulkarni, Dr. Vikram Singh

Abstract: Fungal infections pose a significant global health burden, particularly in immunocompromised individuals. The outcome of fungal infections is determined by complex interactions between the host immune system and pathogenic fungi. This paper reviews current understanding of host–pathogen interactions in fungal infections, emphasizing mechanisms of immune recognition, evasion, and fungal virulence strategies. Innate immune cells, including neutrophils, macrophages, and dendritic cells, initiate defense by recognizing pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs). Adaptive immunity involving T helper subsets orchestrates long-term protection. Fungi employ strategies such as biofilm formation, secretion of immunomodulatory molecules, and phenotypic switching to evade host defenses. Tables summarize key host immune responses, fungal evasion mechanisms, and clinical implications. Understanding these interactions provides a foundation for the development of novel antifungal therapeutics and vaccines aimed at mitigating morbidity and mortality associated with fungal infections.

Keywords: Fungal infections, Host–pathogen interactions, Innate immunity, Adaptive immunity, Virulence factors, Immunomodulation, Biofilm formation