FINALS TOPIC ALL Flashcards
Detection of possible antibodies produced by patients with rheumatoid arthritis
Rheumatoid factor latex agglutination test
Conditions in which damage to organs or tissues results from the presence of autoantibody or auto-reactive cells
Autoimmunity
These cells would lead to the production of autoantibodies
Autoreactive cells
The ability of the immune system to recognize self-produced antigens as a non-threat while recognizing foreign antigens as a threat
Self-tolerance
This type of self tolerance happens in the primary lymphoid organs (BM and Thymus). It has a positive and negative selection process in T cell maturation. It is not 100% effective that is why some of the cell reactive T cells can pass through.
Central tolerance
What is the main function of central tolerance?
Shut down/remove those cells that are self-reactive B or T lymphocytes. It triggers apoptosis
This type of self-tolerance happens in the secondary lymphoid organs (spleen, Lymph nodes, etc.).
Peripheral tolerance
What cells mediate the peripheral tolerance which suppress the immune response to the self-antigens ?
T-regulatory cells
This particular TH cell is associated as the primary mediators in the development of auto-immune disorders
TH1
It is thought to be caused by the loss or breakdown of self-tolerance (there is a problem with the T regulatory cells)
Autoimmunity
Other mechanisms that are thought to be contribute to autoimmunity:
Release of sequestered antigens, molecular mimicry, polyclonal B-cell activation, inheritance of MHC genes
Hormone related to autoimmunity which makes females more prone in the development of autoimmune disease
Estrogen
Tissue target of Hashimoto’s thyroiditis
Thyroid
Target tissue of Grave’s disease
Thyroid
Tissue target of pernicious anemia
Gastric parietal
Tissue target of Addison’s disease
Adrenal glands
Tissue target of Type 1 diabetes mellitus
Pancreas
Tissue target of Myasthenia gravis
Nerve muscle synapse
Tissue target of multiple sclerosis
Myelin sheath of nerves
Tissue target of autoimmune hemolytic anemia
Red blood cells
Tissue target of idiopathic thrombocytopenic purpura
Platelets
Tissue target of goodpasture’s syndrome
Kidney, lungs
Tissue target of rheumatoid arthirtis
Joint, lungs, skin
Tissue target of scleroderma
Skin, gut, lungs, kidney
Tissue target of systemic lupus erythematous
Skin, joints, kidney, brain, heart, lungs
Considered as the most systemic autoimmune disease
Systemic lupus erythematosus
It affects cytokine production and may influence T cells which becomes more active in a particular response
Estrogen
Genetic marker that is strongly associated with rheumatoid arthritis
HLA-DR4
Principle of RF latex agglutination test
Passive agglutination
What is the antibody detected in rf latex agglutination test?
Rheumatoid factor
Is RF non-specific or specific?
Non specific
What immunoglobulin classification is RF in?
IgM
The mechanism of RF:
IgM antibodies act against the FC region of IgG molecule which creates an immune complex the becomes deposited in the joints
What type of hypersensitivity reaction is RF classified in?
Type 3
Does a positive result in RF latex agglutination test mean the patient already has RA?
No
Done as a screening test to see if the patient is positive or negative with RF
RF latex agglutination qualitative method
Normal levels for RF latex agglutination test
Less than 8 iu/mL
Limit of sensitivity of RF latex agglutination test
8 iu/mL
Most commonly acquired spirochete disease in the US
Syphilis
What is the causative agent of syphilis?
Treponema pallidum subspecies pallidum
The causative agent of yaws
Treponema pallidum subspecies pertenue
The causative agent of nonvenereal endemic syphilis
Treponema pallidum subspecies endemicum
The causative agent of pinta
Treponema carateum
What is the principal mode of transmission of syphilis?
Sexual contact
This stage of syphilis is characterized by the formation of chancre
Primary syphilis
When does the formation of chancre in syphilis occur?
10-90 days after infection
This stage of syphilis may give positive result to direct detection (microscopic, IFA)
Primary syphilis
This stage of syphilis is characterized by lymphadenopathy, malaise, fever, pharyngitis, and a rash on the skin and mucous membranes. Chancre may also be present.
Secondary syphilis
This stage of syphilis is characterized by a systemic dissemination of microorganism.
Secondary syphilis
At this stage of syphilis, patients are noninfectious, with the exception of pregnant women.
Latent syphilis
This stage of syphilis is characterized by the absence of symptoms.
Latent syphilis
This stage of syphilis is when the patient serum sample may give a positive result in serological test for syphilis.
Latent syphilis
This stage of syphilis appears anywhere from months to years after secondary infection. Typically, this occurs most often between 10 and 30 years following the secondary stage.
Tertiary syphilis
Three major manifestations of tertiary syphilis
Gummatous syphilis, cardiovascular disease, neurosyphilis
Localized area of granulomatous inflammation that is commonly found in the skin, bones, or subcutaneous tissues.
Gummas
Lab test for syphilis that uses darkfield and fluorescence microscope and fluorescence labelled antibody.
Direct detection of spirochetes
Lab tests for syphilis under direct detection of spirochetes:
Dark field microscope, direct immunofluorescence assay
Laboratory test for syphilis which detects antibody cardiolipin. It has been traditionally been used to screen for syphilis because of their high sensitivity and ease of performance.
Nontreponemal serological test
Specific type of precipitation that occurs over a narrow range of antigen concentrations.
Flocculation
Examples of nontreponemal test:
VDRL, RPR, TRUST (toluidine red unheated serum test), USR (unheated serum reagent), RST (regain screen test)
This lab test for syphilis detects treponemal antibodies. It has the highest sensitivity for detecting infection.
Treponemal serological test
It is both a qualitative and quantitative slide flocculation test for serum and spinal fluid.
Venereal disease research laboratory
What does the reagent (antigen) of VDRL consist of?
0.03% cardiolipin
0.9% cholesterol
0.21% lecithin
Rotation speed and timing for serum VDRL
180 rpm for 4 mins
Rotation speed and timing for CSF VDRL:
180 rpm for 8 mins
At what temperature should the VDRL be performed?
Room temperature / 23-29C
What is the antibody against cardiolipin?
Reagin
How do you inactivate VDRL serums?
Incubate serum at 56C for 30 mins
What is the required circle for VDRL?
14mm ring
It uses 18 gauge needles without bevel. Calibrated to drop 60 drops of antigen suspension per mL.
Qualitative Serum VDRL
It uses 19 gauge needle without bevel. Calibrated to drop 75 drops of antigen suspension per mL.
It can use 23 gauge needle may be used which dispenses 100 drops per mL.
Quantitative serum VDRL
It uses 21 or 22 gauge needle that can dispense 100 drops of antigen suspension per mL.
CSF VDRL
GRADING OF FLOCCULATION
Reactive- medium to large clumps
Weakly reactive- small clumps
Nonreactive- no clumps or slight roughness
This test is a modification of VDRL which involves macroscopic agglutination
Rapid plasma reagin test
Where is the cardiolipin-containing antigen suspension bound to in RPR?
Charcoal particles
What is the composition of RPR antigen?
0.03% cardiolipin, 0.9% cholesterol, 0.21% lecithin, EDTA, thimerosal, choline chloride
What hamilton syringe is used for RPR?
20 gauge
Rotation and timing of RPR?
100 rpm for 8 mins
Which component of the RPR reagent inactivates the serum?
Choline chloride
What is the test circle size for RPR?
18 mm
What done after a positive reaction is shown in RPR test?
Run a semi-quantitative method to determine the titer
It is also called as the lateral flow assay or lateral flow immunoassay
Immunochromatography
What is the principle applied in serological test kits?
Immunochromatography
What are the components of the lateral flow assay?
Sample pad, conjugate pad, membrane pad, absorbent pad
Absorbent pad on to which the sample is applied that might be containing the target analyte.
Sample pad
What is the typical composition of sample pad?
Woven mesh or cellulose fiber
What should the sample pad demonstrate to avoid lost of analytes?
Low protein binding
It is typically composed of non-woven glass fiber, into which the detection reagent has been dried
Conjugate pad
It contains a dye labeled antibody conjugate, specific for the target analyte in this sample
Conjugate pad
What is the most commonly used label in immunochromatography? This is also the reason why the reaction is colorimetric.
Colloidal-gold nanoparticles
What is the most important element in the lateral flow assay?
Membrane pad
What is the composition of membrane pad?
Nitrocellulose, cellulose acetate, polyvinylidene fluoride, charge-modified nylon, or polyethersulfone
It is considered to be the most commonly used membrane pad
Nitrocellulose
What is the purpose of membrane pad?
Captured antibodies are immobilized across the membrane, typically in two lines
It basically consists of specie specific antibody for the detection of the antibodies available on the conjugate pad.
Control line
This is found at the end of the lateral flow immunoassay. Functions to increase the volume of sample which enters the test strip.
Absorbent pad
In this assay, the positive reaction will show a colored line on the “T”-test line.
Direct assay or sandwich assay
Test kits that utilizes direct assay
HBsAg, HIV, Dengue
In this type of assay, the sign of positive reaction is an absence of colored line on the test line.
Competitive assay
What test kits use competitive assay?
Drugs of abuse: Methemphetamine hydrochloride, tetrahydrocannabinol, etc.
Inflammation of liver caused by a heterogenous group of viruses
Hepatitis
Hepatitis A
Picornaviridae
Hepatitis B
Hepadnaviridae
Hepatitis c
Flaviviridae
Hepatitis D
Deltaviridae
Hepatitis E
Hepeviridae
The only DNA hepatitis virus
Hepatitis B virus
Mode of transmission of hepatitis b
Parenteral, perinatal, sexual intercourse
What should the mother be positive for in order for vertical transmission be possible for hepatitis b?
Hepatitis B envelop antigen (HBeAg)
How many doses of the vaccine should a person acquire for the prevention of hepatitis b?
3
What are the immune responses that our body tends to produce?
Anti-HbS, anti-HbC, anti-HbE
First marker to appear in blood after infection and it’s a sign that the patient is in acute stage of hepatitis B infection
HBsAg
A sign that there is a viral replication happening on the patient circulation and sign of infectivity which means that the patient can transmit the virus to other hosts
HBeAg
The only serological marker for hepatitis b infection that is not detectable in serum sample because of the HBe which masks it.
HBcAg
What hepatitis serological marker can be detected only through liver biopsy?
HBcAg
The first antibody to be detected in hepatitis B
Anti-HBc
2 forms of Anti-HBc
IgM and IgG
The only serological marker that can be detected during the window period of hepatitis B infection.
Anti-HBc
This is when all of the serological markers for hepatitis B are negative.
Window period
The marker detected during the window period of hepatitis B
IgM anti-HBC
Serological marker that is a sign that the patient is in chronic stage of hepatitis B infection
IgG Anti-HBc
Indicates that the patient is recovering from hepatitis B infection
Anti-HBe
Last antibody to appear during hepatitis b infection. It is also present on immunized patients.
Anti-HBs
One step assay designed for qualitative determination of HBsAg in human serum or plasma
SD BIOLINE HBsAg
What is the membrane strip of the SD BIOLINE test cassette pre-coated with?
Mouse monoclonal anti-HBs capture antibdy on test band region
After how many minutes should you interpret the results for HBsAg
20 mins
Family of HIV
Retroviridae
HIV with worldwide distribution (common to US and Europe)
HIV I
HIV that is common to West Africa and less pathogenic
HIV II
What are the three major structural gene of HIV?
Gag, Pol, Env
Reverse transcriptase (important enzyme during replication process) in HIV
P64
An important enzyme during replication process, to integrate genetic material to the host genes
P32
Screening tests for HIV Ab
ELISA(indirect), ELISA (competitive assay), slide agglutination test, RIA
Confirmatory tests for HIV Ab
Western blot assay, indirect immunofluorescence assay
Most widely used supplementary test for confirming reactive HIV ELISA Ab test. Used to detect proteins
Wester blot assay
Indication of positive result for westernblot
Positive for At least 2 out of 3 Ab
Considered confirmatory for HIV
2 (+) ELISA’s. And 1 (+) western blot
Southern blot hybridization
Detects DNA
PCR
Tests HIV RNA
Norhtern blot
Measures mRNA Ag
Ab that appear relatively early after exposure to HIV
Anti-p24, anti-p55 (earliest is Anti-p24)
Ab that appear slightly later but remain throughout all diseases stages in an HIV-infected px
ANti-gp41, gp120, gp160
A rapid, qualitative test kit for the detection of Abs to all isotypes specific to HIV-1 including subtype-0 and HIV-2 SIMULTANEOUSLY IN HUMAN SERUM, PLASMA OR WHOLE BLOOD
SD BIOLINE HIV-1/2 3.0
What is the membrane pad of SD BIOLINE HIV-1/2 3.0 coated with?
HIV-1 capture antigen (gp41, p24) on test band 1 region, recombinant HIV-2 capture antigen (gp36) on test band 2 region
Mosquitoes that transmit dengue virus
Aedes aegypti, aedes albopticus
Ab that rises between 3-5 days of infection and may persist up to 60 days of dengue
IgM
Ab that appears a the 14th day and persists for life following dengue
IgG
Principle of SD bioline: rapid dengue IgG and IgM
Solid-phase immunochromatography
Highly conserved glycoprotein that is present at high concentrations in the sera of dengue-infected patients during the early clinical phase of the disease
NS1 Ag
Found from the first day and up to 9 days after onset of fever in samples of primary and secondary dengue infected patients
NS1 Ag
