1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
mars1129 [50]
3 years ago
6

Streptococcus pneumoniae can escape phagocytic clearance by which mechanism

Biology
1 answer:
Stells [14]3 years ago
6 0
<span>he Streptococcus pneumoniae capsule is vital for virulence and may inhibit complement activity and phagocytosis. However, there are only limited data on the mechanisms by which the capsule affects complement and the consequences for S. pneumoniae interactions with phagocytes. Using unencapsulated serotype 2 and 4 S. pneumoniae mutants, we have confirmed that the capsule has several effects on complement activity. The capsule impaired bacterial opsonization with C3b/iC3b by both the alternative and classical complement pathways and also inhibited conversion of C3b bound to the bacterial surface to iC3b. There was increased binding of the classical pathway mediators immunoglobulin G (IgG) and C-reactive protein (CRP) to unencapsulated S. pneumoniae, indicating that the capsule could inhibit classical pathway complement activity by masking antibody recognition of subcapsular antigens, as well as by inhibiting CRP binding. Cleavage of serum IgG by the enzyme IdeS reduced C3b/iC3b deposition on all of the strains, but there were still marked increases in C3b/iC3b deposition on unencapsulated TIGR4 and D39 strains compared to encapsulated strains, suggesting that the capsule inhibits both IgG-mediated and IgG-independent complement activity against S. pneumoniae. Unencapsulated strains were more susceptible to neutrophil phagocytosis after incubation in normal serum, normal serum treated with IdeS, complement-deficient serum, and complement-deficient serum treated with IdeS or in buffer alone, suggesting that the capsule inhibits phagocytosis mediated by FcÎł receptors, complement receptors, and nonopsonic receptors. Overall, these data show that the S. pneumoniae capsule affects multiple aspects of complement- and neutrophil-mediated immunity, resulting in a profound inhibition of opsonophagocytosis.</span>
You might be interested in
Which series correctly lists the order of species (from a to <br> e. that belong on the timeline?
Ann [662]
What are the species that are labeled a to e?
6 0
3 years ago
Which statement best describes a typical difference that could be found between the “Analysis” and “Conclusion” sections of a la
Rashid [163]
The answer for the given question above is the second option. The statement that best describes a typical difference that could be found between the "Analysis" and "Conclusion" section of the lab report is this: Only the "Analysis" section includes specific data comparisons, and the only "Conclusion" section suggests further research. Hope this helps.
3 0
3 years ago
About 99% of the atmosphere is composed of
hichkok12 [17]
Nitrogen and oxygen make up about 99%of the atmosphere. I'm not sure if it will help! But thats all I know.
5 0
3 years ago
What basic life functions must all unicellular organisms preform to<br> survive?
Digiron [165]

Answer:

The one cell of a unicellular organism must be able to perform all the functions necessary for life. These functions include metabolism, homeostasis and reproduction. Specifically, these single cells must transport materials, obtain and use energy, dispose of wastes, and continuously respond to their environment

Explanation:

4 0
2 years ago
Toxicology is the study of ________. toxin effects on human health toxin effects on the environment risks and hazards the relati
Elena-2011 [213]
Toxicology is the study of toxin effects on human health. The individuals or professionals who carry out toxicology are called toxicologists. In toxicity testing, the dose of a chemical above which there is a measurable decline in the health of the organism being tested is referred to as the toxicity threshold. After identifying the effects and the toxins in the body of an organisms toxicologists device ways of removing or neutralizing the toxin so as to avoid any damaging effects to the body tissues. 
3 0
3 years ago
Other questions:
  • Which part of the brain plays a major role in homeostasis by regulating such processes as heart rate and breathing through the a
    15·1 answer
  • How could your life change if global warming continues as scientists think it will?
    15·1 answer
  • Which are characteristics of medusae?
    11·1 answer
  • What happens when a atom gains and electron
    15·2 answers
  • Even-aged management practices involves cleaning trees that ________.
    13·2 answers
  • What are two ways that energy can be conserved?
    11·1 answer
  • Within each eon, identify major events and the types of life that dominated the Earth during the time.​
    11·1 answer
  • Help Me To Check With This
    12·1 answer
  • Which of these pictures show the last (most recent) in the sequence of
    14·2 answers
  • Insulin is made by pancreatic cells, packaged in small vesicles, and then released into the bloodstream. this describes what sor
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!