Biofilm formation has been implicated in persistent tissue infections such as chronic wound infection, chronic otitis media, chronic osteomyelitis, chronic rhinosinusitis, recurrent urinary tract infection, endocarditic and cystic fibrosis-associated lung infection.They are equally resistant to various antimicrobial treatments compared to their planktonic form

1. CLINICAL IMPLICATIONS OF BACTERIAL BIOFILMS
A SEMINAR PRESENTATION
BY
Yakubu, YUNUSA
B. A. TYTLER
B. O. OLAYINKA
DEPARTMENT OF PHARMACEUTICS &
PHARMACEUTICAL MICROBIOLOGY, FACULTY OF PHARMACEUTICAL
SCIENCES, AHMADU BELLO UNIVERSITY, ZARIA.
SEPTEMBER, 2016
1

2. Outline of Presentation
• Introduction
• Composition of biofilm
• Biofilm formation
• Biofilm formation and quorum sensing
• Why clinicians study biofilms
• Future direction
• Conclusion
• References
2

3. Introduction
• In recent time, microorganisms have been
discovered to evolved various mechanisms of
surviving a harsh environment; among which are
production of biochemical compounds such as
biofilm, biosurfactants, and enzymes.
• Biofilms are self synthesized extrapolymeric
slimy matrix that encloses a sessile microbial
community whose cells are characterized by their
attachment to either biotic or abiotic surfaces
(Vasudevan, 2014).
• Biofilm consist of either a single or multiple
species of microorganisms (Flemming and
Wingender, 2010).
• Biofilms promote and regulate metabolic
activities, Provision of nutrients and protection
(Vasudevan, 2014).
3

4. Composition of Biofilm
• Microbial cells
• Extra polymeric substances, EPS
(Oliveira and Cunha,2008)
EPS provides essential nutrients, protection, architectural integrity, enables
genetic and intracellular transfer (Donlan, 2000).
Table 1: Composition of biofilm (Vasudevan, 2014).
S/NO Component Percentage of Matrix
1 Water Up to 97%
2 Microbial cells 2-5%
3 polysaccharides 1-2%
4 Proteins <1-2% (including enzymes)
5 DNA and RNA <1-2%
6 Ions Bound and free
4

5. Biofilm formation
 Biofilm formation begins when microorganisms response to factors such as
• Cellular recognition of attachment site,
• Nutritional cues
• Exposure of planktonic cells to sub-inhibitory concentration of antibiotics
(Lieve van et al., 2012)
 Stages in biofilm formation include,
Adhesion/Attachment, adhesion of bacteria to a surface is a two
step process; primary bacterial adhesion and secondary
bacterial adhesion (Chelius and Duffy, 2013)
Intracellular aggregation, formation of monolayer
involving polysaccharide adhesin (PIA) similar to poly–N-
acetylglucosamine (Helimann, 2011)
Biofilm maturation, biofilm become complex, cells actively
proliferating leading to increase in population density, Forms
glycocalyx and mushroom- like structure (Chelius and Duffy, 2013;
Niels et al., 2011).
Biofilm dispersal, nutrients and Oxygen become depleted and
biofilm begin to degrade and cells released from the mushroom like
structure (Karatan and Watnick 2009; Hong et al. 2010; Rowe et al.
2010) 5

6. Fig1 Stages in biofilm formation. Adopted from Kirk E. Anderson Genetics and Microbial Ecology
6

7. 7

8. Quorum sensing and Biofilm formation
8

9. Clinicial significance of biofilms
Bacterial
Biofilms
Antimicrobial
tolerance
Medical
device related
infections
Chronic
infections
Modulation of
immune
response
9

10. Biofilm and antimicrobial resistance.
• Agents may form complex
with EPS (Romling and
Balsallobre, 2012)
• Poor penetration of biocide
agent resulting from EPS
(Manavathu and Vazquez,
2014).
• Passage of genetic
determinant via horizontal
gene transfer (Juhas, 2013).
• Expression of molecular
efflux pump (Bueno, 2014)
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11. Medical device related infections
• Most medical implants such as
intravascular catheters, Devices
use in orthopedic shunts, Stent,
suture are susceptible to biofilm
formation (Romling and
Balsalobre, 2012).
• Provide a reservoir for recurrent
and at times life threatening
bloodstream and urinary tract
infections (Desai et al., 2014).
• Biofilm causes device failure
11

12. Biofilms and chronic diseases
 Chronicity in diseases such as
diabetic chronic wounds,
• Cystic fibrosis,
• Bronchopneumonia,
• Otitis media,
• Osteomyelitis (Bjarnsholt et al.,
2009; Homoe et al., 2009;
Tacconelli et al., 2009)
 Biofilm triggers
proinflammatory responses
harmful to host tissues.
 Responsible for delayed healing
in diabetic wound (Zhao et al.,
2013). 12

13. Modulation of immune response
EPS component(s) at times triggers proinflammatory response that fails to recognize host tissue
as ‘self’ with detrimental effects (Nibali et al., 2014).
Microbial biofilm mediated inflammatory response halts the chronic wound healing process at
the inflammatory stage and prevent proliferation and healing (Manavathu and Vazquez, 2014).
Lipopolysaccharides released from dental plaque initiate imflammatory immune response
which triggers the release of inflammatory mediators (Benakanakere and Kinane, 2012).
Bacteria-in-wound protected by biofilm from the host immune system.
13

14. Future direction for combating biofilm menace
• Development of antibiofilm antimicrobial agents directed to targeting one or more of
the major stages of biofilm development.
• Extra polymeric matrix busting’ antibiofilm drug should have the ability to disrupt
existing biofilm.
• The use of bacterial/fungal adhesion resistant material for the construction of
medical devices associated with biofilm.
• Development of vaccines directed to targeting quorum sensing.
14

15. Conclusion
• With the increasing use of life-saving and quality of life
improving medical devices such as catheters, prosthetics and
other beautification devices either on a long term or permanent
basis, the incidence of microbial biofilm is on the rise and
continue to increase in the future causing formidable clinical
problems such as difficulties in identification of microbial cells
in EPS and making of therapeutic decisions , higher tolerance
of antimicrobial agents, reservoir for current and recurrent of
infectious diseases, and autoimmune diseases resulting from
immunomodulation of host immune system if proper measures
are not taken to curtail it effect in clinical setting.
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16. References
Benakanakere M, and Kinane DF. (2012). Innate cellular responses to the periodontal biofilm. Front Oral
Biology15:41-55.
Bjarnsholt T, Jensen PØ, and Fiandaca MJ, (2009). Pseudomonas aeruginosa biofilms in the respiratory
tract of cystic fibrosis patients. Pediatric Pulmonology 44: 547–558.
Bueno J (2014). Anti-Biofilm Drug Susceptibility Testing Methods: Looking for New Strategies against
Resistance Mechanism. Journal Microbial Biochemical Technology S3: 004.doi:10.4172/1948-
5948.S3-004
Chelius Cynthia, and Duffy Catherine (2013). Effect of Cranberries on biofilms. Worcester polytechnic
institute.
Desai JV, Mitchell AP, and Andes DR. (2014). Fungal biofilms, drug resistance, and recurrent infection.
Cold Spring Harb Perspectives in Medicine 1:4(10).
Donlan RM (2002). Biofilms: microbial life on surfaces. Emerging Infectious Diseases 8(9): 881-890.
Flemming HC, and Wingender J (2010). The biofilm matrix. Nature Reviews Microbiology 8(9): 623-633.
Heilmann C (2011). Adhesion mechanisms of Staphylococci. Advances in Experimental Medicine and
Biology 715: 105-123.
Homøe P, Bjarnsholt T, Wessman M, Sørensen H C, and Johansen HK. (2009). Morphological evidence
of biofilm formation in Green- landers with chronic suppurative otitis media. Eur Archive
Otorhinolaryngology 266: 1533–1538
Hong SH, Lee J, and Wood TK. (2010). Engineering global regulator Hha of Escherichia coli to control
biofilm dispersal. Microbial Biotechnology 3: 717–728.
Juhas M. (2013). Horizontal gene transfer in human pathogens. Critical Reviews in Microbiology.
16

17. References cont’dKaratan E, and Watnick P. (2009). Signals, regulatory networks, and materials that build and break
bacterial biofilms. Microbiology and Molecular Biology Reviews 73: 310–347.
Lieve van Mellaert, Mohammed Shahrooel, Dorien Hofmans, and Johan van Eldere (2012).
Immunoprophylaxis and immunotherapy of Staphylococcus epidermis infections. Expert reviews of
vaccine 11(3):319-334.
Manavathu EK, and Vazquez JA. (2014). Biofilms: Emerging Importance in Infectious Diseases. Journal
of Multidisciplinary Pathology 1(2):1-13.
Nibali L, Henderson B, and Sadiq ST (2014). Genetic dysbiosis: the role of microbial insults in chronic
inflammatory diseases. Journal of Oral Microbiology.
Oliveira A, and Cunha MLRS (2008). Bacterial biofilms with emphasis on coagulase-negative
Staphylococci. Journal of Venomous Animals and Toxins Including Tropical Diseasess 14(4): 572-
596.
Romling U, and Balsalobre C. (2012). Biofilm infections, their resilience to therapy and innovative
treatment strategies.Journal of International Medicine 272(6):541-561.
Rowe MC, Withers HL, and Swift S. (2010). Uropathogenic Escherichia coli forms biofilm aggregates
under iron restriction that disperses upon the supply of iron. FEMS Microbiology Letter 307: 102–
109.
Tacconelli E, Smith G, Hieke K, Lafuma A, and Bastide P. (2009). Epidemiology, medical outcomes and
costs of catheter- related bloodstream infection in intensive care units of four European countries:
litterature- and registry-based estimates. Journal of Hospital Infections 72: 97–103.
Vasudevan R (2014). Biofilms: Microbial Cities of Scientific Significance. Journal of Microbiology and
Experimentation 1(3)
Zhao G, Usui ML, and Lippman SI (2013) Biofilms and Inflammation in Chronic wounds. Advance
Wound Care (New Rochelle) 2(7):389-399. 17

18. Thank
You For
listening
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