Auto - Inflammtory Diseases Flashcards
What is the difference between innate and adaptive immune system?
- innate immunity - body immediate, general defence against pathogens 🦠
- adaptive immunity - specialised, targeted response that developed over time
What is the difference between ** auto inflammation 🔥 ** and ** auto - immunity **?
✅ auto inflammation -> where the body will mistakenly trigger inflammation without an external threat.
✅ Autoimmunity —> when the body attacks its own tissues and cells
What sets the boundaries for auto immunity?
- mutations associated with cells and molecules invoved in the adaptive immune system (ie specific + targeted).
What sets the boundaries for auto - inflammation?
- mutations in cells associated with innate immunity at disease prone sites (rmb innate immunity associated with inflammation)
What are familial monogenic diseases?
🧬 genetic disorders, that are caused by a single gene.
The disease is often inherited within a predictable pattern within families, and can result in specific health problems or conditions.
What are familial monogenic diseases caused by?
- mutations in a single gene (ie in CF, disease is caused due to mutations in the CFTR gene and thus non functional CFTR)
What are the general characteristics of monogenic auto - inflammatory diseases?
✅ unprovoked attacks of inflammation (ie may not be due to infection etc there is no stimulus)
✅ absence of high tier autoantibodies or antigenic specific T cells , ie the adaptive immune response - ie the inflammation seen is largely mediated by the cells and molecules of the innate system.
✅ pre - existing errors of the innate immune system — ie significant boost predisposition.
Give a few examples of familial monogenic auto inflammatory disorders?
- 🥵 familial Mediterranean fever
- 🥶 CAPS (cyropyrin associated periodic syndromes).
- Blau syndrome
Which gene is mutated in Familial Mediterranean Fever and what are the clincal features / symptoms of FMF?
Gene : 🧬 MEFV protein
Clinical Features : periodic fevers lasting 3 0 7hrs), inflammation of serous tissue (ie lining the heart and inner abdomen) , arthritis.
Which gene is mutated in Cryopyrin - associated period syndromes (ie FCAS, MWS, and NOMID) and what are the clincal features / symptoms of CAPS?
- 🧬 NLRP3 gene
Clinical features : - 🥶 cold induced autoinflammation
- 👂 cochlear inflammation
- 🥵 fevers
- 🤧 sterile menigitis
- 🦴 Bone lesions.
Which gene is mutated Blau Syndrome and what are the clincal features / symptoms of Blau Syndrome ?
🧬 mutated gene : NOD2
Clinical features :
- 🍬 granulomatous dermatitis
- uveitis (inflammation of the inner eye) n
- arthritis 👵
Are these diseases, FMF, CAPS and Blau syndrome, autosomal dominant or recessive?
FMF - AR
BS - AD
CAPS - AD
Give 3 examples of the cryopyrin associated periodic syndrome (CAPS) diseases?
- ✅ familial cold autoinflammatory syndrome (FCAS)
- ✅ Muckle - Wells syndrome (MWS)
- ✅ NOMID/ CINCA
What is CAPS?
A spectrum of disease ranging from mildFCAS to severe NOMID/CINCA. They are rare and hereditary inflammatory diseases that each encompass their own 3 phenotypes.
CAPS
What is FCAS and and what are the symptoms?
Familial cold autoinflammatory syndrome.
- inflammation that occurs when weather is cold 🥶and temperatures are low ❄️
- symptoms : rash on the skin, arthralgia (joint pain), conjunctivitis (red eye)
Mild caps
CAPS :
What is MWS and what are the symptoms?
Muckle - Wells Syndrome
CAPS characterised by skin / urticaria rash ** and ** sensorineural deafness 👂 🧏🏽♀️
Between mild and severe CAPS
CAPS
What is NOMID/CINCA and what are the symptoms?
A more sporadic (ie occurs randomly) and severe CAPS disease.
Symptoms include : progressive chronic meningitis, visual 👁️ and intellectual 🧠 damage, and destructive arthritis 🦴
Auto - immune diseases tend to have flares what are these?
✅ periodic fever syndromes where the disease will amplify and worsen and then go back to normal state periodically and sporadically.
💊 there isn’t necessarily a particular target for most of these types of conditions
What is caspase 1?
A converting enzyme that cleaves other proteins such as ** precursors for inflammatory cytokines IL - 1B and IL - 18 **
What are NLR proteins?
Other wise known as “Nucleotide - binding Oligomerization Domain - like receptors (NOD)” are a type of protein/ receptor that detect harmful pathogens 🦠 in our cells.
When they recognise these threats, they triger a series of signals that will ➕ activate our immune system to defend against the invading cells.
Give two examples of inflammatory cytokines?
- IL - 1B
- IL - 18.
What are inflammasomes
- 🥵 receptors of the **innate immune system* (obvs, they are inflammatory) —> they are large protein receptor structures made out of NLR proteins.
- ✅ they regulate the activation of capsase 1 and they can induce inflammation in response to infectious microbes and molecules deceived from host proteins.
Describe the structure of the NLRP3 inflammasomes?
They are composed of a N - terminal effector domain that comprise capsase recruitment domains (CARD) and pyrin domains.
What does activation fo the NLR lead to ?
Triggering of severe important immune processes such as inflammasomes formation (lots of NLR proteins conjugating to form multi protein complexes, that activate the release of pro - inflammatory cytokines IL -1 beta and IL -18).
Induction of antimicrobial responses and initiation of cell death (pyroptosis to avoid spread of pathogens by removing infected cells).
How does activation of the NLRP3 inflammasomes lead to the release of pro - inflammatory cytokines?
NLR proteins - in response to threat will form a complex , ie the NLRP3 inflammasomes.
This inflammasomes will activate procapsase 1 by cleaving it into its active form capsase 1.
Capsase 1 will then act enzymatically and will cleave IL- 1Beta and IL - 18 into their active form so we get an increase int he cytokines IL- beta and IL - 18.
What is caspase 1 and what is its function?
- enzyme
- function : cleave other proteins to ** activate apoptosis** and pryoptosis. Will also activate pro - inflammatory cytokines (ie IL - 1 beta)
What is IL - 1 beta and its function?
- interleukin involved in the promotion of inflammation 🥵, induction of fever 🤒, and activation of immune cells 👺 - thus is * pro - inflammatory*.
🤢 it also has a role in inflammatory disease and also contributes to response against infection.
What is IL - 18?
- interleukin involved in enhancing the production of IFN - Y, as well as contributing to the immune response, and defence against certain infections.
It also has a role in auto - immune and inflammatory response.
What are PAMPS and DAMPS?
PAMPS - pathogen - associated molecular patterns that are recognised by immune cells indicating the presence of pathogens. They are released from the pathogen.
DAMPS - damage associated molecular patterns - released by injured or damaged cells into the extracelluar space that will signal danger to the immune system.
How do PAMPS and DAMPS also lead to the activation of a pro - inflammatory response?
- They are detected by the immune receptors ie PRR and TLR
- detection leads to changes in the formation of NLRP inflammasomes which will multimerize.
- CARD domain of the inflammasomes picks up the pro capsase enzyme and activates it to capsase 1 (active form ✅).
- Active Capsase 1 will then convert pro - IL to active forms (ie IL - 1Beta and IL - 18) which are then released from teh cell leasing to inflammation and release of inflammatory cytokines.