Immunohistochemistry (IHC) is the localization of a known antigen in tissues by utilizing antibodies directed towards that (specific) antigen. In this presentation, we will introduce the procedure of IHC and the troubleshooting solutions.
Immunohistochemistry (IHC) is the localization of a known antigen in tissues by utilizing antibodies directed towards that (specific) antigen. In this presentation, we will introduce the procedure of IHC and the troubleshooting solutions.
Immunohistochemistry (IHC) is the process of detecting antigens (e.g. proteins) in cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological tissues.
https://www.creative-bioarray.com/protocol/immunohistochemistry-protocol.htm
Immunohistochemistry (IHC) is a highly sensitive method that allows the localization of antigen within a cell or a tissue with high resolution. The method is based on the use of a primary antibody that specifically binds to its complementary antigen. The bound antibody may then be visualized by a variety of methods such as colorimetric end points.
This method is used to visualise the localisation and quantity of a protein of interest. The target protein is bound to by a specific primary antibody, which in turn is detected by a secondary antibody conjugated to a fluorophore. A fluorescent or confocal microscope is used to visualise the protein.
Immunocytochemistry (ICC) differs from immunohistochemistry (IHC) in that the former is performed on samples of intact cells that have had most, if not all, of their surrounding extracellular matrix removed. In contrast, immunohistochemical samples are sections of biological tissue, where each cell is surrounded by tissue architecture and other cells normally found in the intact tissue. These differences cause the samples to be prepared differently. For ICC, the sample requires permeabilisation so that the antibodies can reach the intracellular targets. Depending on the thickness of the sample, IHC samples do not require this.
Do you have a technical question? Get in touch: info@stjohnslabs.com
This is a presentation I prepared to demonstrate my mastery of the basics of Immunohistochemistry during my first two months of employment as a Biologist at the Cell Marque Corporation. Please note, there are a few slides that appear to be dysfunctional and overlapping; this is due to the fact that these particular slides included complex animations that I designed to illustrate various scientific concepts related to the practice of Immunohistochemistry. If you wish to view this presentation in its entirety (animations included), feel free to contact me via LinkedIn and I will gladly provide you with a fully-functional version.
Immunohistochemistry (IHC) is the process of detecting antigens (e.g. proteins) in cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological tissues.
https://www.creative-bioarray.com/protocol/immunohistochemistry-protocol.htm
Immunohistochemistry (IHC) is a highly sensitive method that allows the localization of antigen within a cell or a tissue with high resolution. The method is based on the use of a primary antibody that specifically binds to its complementary antigen. The bound antibody may then be visualized by a variety of methods such as colorimetric end points.
This method is used to visualise the localisation and quantity of a protein of interest. The target protein is bound to by a specific primary antibody, which in turn is detected by a secondary antibody conjugated to a fluorophore. A fluorescent or confocal microscope is used to visualise the protein.
Immunocytochemistry (ICC) differs from immunohistochemistry (IHC) in that the former is performed on samples of intact cells that have had most, if not all, of their surrounding extracellular matrix removed. In contrast, immunohistochemical samples are sections of biological tissue, where each cell is surrounded by tissue architecture and other cells normally found in the intact tissue. These differences cause the samples to be prepared differently. For ICC, the sample requires permeabilisation so that the antibodies can reach the intracellular targets. Depending on the thickness of the sample, IHC samples do not require this.
Do you have a technical question? Get in touch: info@stjohnslabs.com
This is a presentation I prepared to demonstrate my mastery of the basics of Immunohistochemistry during my first two months of employment as a Biologist at the Cell Marque Corporation. Please note, there are a few slides that appear to be dysfunctional and overlapping; this is due to the fact that these particular slides included complex animations that I designed to illustrate various scientific concepts related to the practice of Immunohistochemistry. If you wish to view this presentation in its entirety (animations included), feel free to contact me via LinkedIn and I will gladly provide you with a fully-functional version.
What is it? The INFORM HER2 Dual ISH DNA Probe Cocktail is a laboratory test that uses DNA probes, with color-forming (chromogenic) dyes attached, to count how many copies of the HER2 gene, located on chromosome 17, are present in a tissue sample. This test, which uses a variation of fluorescence in situ hybridization (ISH), is based on color detection, rather than fluorescence, and is used with samples of tumor tissue removed from breast cancer patients. This test is used by a doctor (pathologist) trained to identify diseases by studying slices of cells and tissues placed on microscope slides. If the test result indicates that too many copies of the HER2 gene (gene amplification) are present in the cancer cell, then a breast cancer patient may be eligible for treatment with the anti-cancer drug Herceptin® (Trastuzumab).
The following presentation contains helpful information regarding Radioimmunoassay (RIA) and Enzyme-Linked Immunosorbent Assay (ELISA), including their history, introduction, advantages, procedures and applications.
Immunofluorescence : Immunofluorescence is a powerful technique that utilizes fluorescent-labeled antibodies to detect specific target antigens..
Fluorescein is a dye which emits greenish fluorescence under UV light. It can be tagged to immunoglobulin molecules.
This technique is sometimes used to make viral plaques more readily visible to the human eye.
Immunofluorescent labeled tissue sections are studied using a fluorescence microscope.
Learn about Type I Polyglandular Autoimmune Syndrome, an incredibly rare autoimmune disorder often characterized by inefficiencies in the adrenal gland.
Immunohistochemistry (IHC) combines histological, immunological, and biochemical techniques for the identification of specific tissue components by means of a particular antigen/antibody reaction tagged with a visible label
Pharmaceutical biotechnology ..in that different blotting techniques such as ELISA , western blotting and southern blotting.There applications and their advantage and disadvantage with their diagrams
Immunohistochemistry is one of the most advance techniques in immuno-staining. In this presentation is a brief introduction to what is IHC, the principle, procedure and applications.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
2. Introduction
• Immunohistochemistry (IHC) combines histological,
immunological and biochemical techniques for the
identification of specific tissue components by means of
a specific antigen/antibody reaction tagged with a visible
label.
• IHC makes it possible to visualize the distribution and
localization of specific cellular components within a cell
or tissue.
3. • IHC is an application of antibodies to tissue
preparation for the localization of target antigens:
• Wide range of specific antibodies
• Highly sensitive detection system
4. Immunohistochemistry utilizes labeled antibodies to
localize specific cell and tissue antigens, and is among the
most sensitive and specific histochemical techniques.
Because many targeted antigens are proteins whose
structure might be altered by fixation and clearing, so
frozen sections are commonly used.
In some cases, paraffin wax can be used for embedding.
5. Immunohistochemistry assays may use
Cells grown, spun into a pellet, frozen or
paraffin embedded and sectioned
Cells grown as a monolayer
OR use tissue sections that are frozen or paraffin embedded
Sections from tissues contain many different kinds of cells
as well as extra-cellular matrix components
cells on slides
6. If the tissue is frozen
The sections may need to be used in immunohisto-
assays as
Tissue section on glass slide: Frozen
Acetone fixed:
- precipitates proteins onto cell surface---may extract lipids
- is needed for many of the “CD” antibodies
Unfixed:
Advantage: antigens are unaltered
Disadvantage: sections may fall off slide during staining
Paraformaldehyde fixed:
- needs to be freshly made, or frozen soon after
7. Tissue section: Paraffin embedded
If the tissue is paraffin embedded
- Deparaffinize ( remove the infiltrated paraffin wax, by using organic solvents)
- The section then needs to be rehydrated, by sequential immersion
in graded alcohols (100%, 70% , 50% and then PBS)
- The deparaffinized section may need to be treated to expose buried
antigenic epitopes with either proteases or by heating in low pH citrate
buffer , or high pH EDTA buffer (Antigen Retrieval)
8. Principle
• The principle of immunohistochemistry is to localize
antigens in tissue sections by the use of labeled
antibodies as specific reagents through antigen-antibody
interactions that are visualized by a marker such as
fluorescent dye, enzyme, radioactive element or
colloidal gold.
9. Antibodies (Immunoglobulins)
• Glycoprotein that are produced by plasma
cells and used by the immune system to
identify and neutralise foreign objects, ie.
bacteria and viruses
• Recognise a specific Antigen- mainly
proteins, glycoprotein, polysaccharides
• Complementary Determining Region
13. A. Raising Antibodies:
• Repeated injection of antigens (proteins, glycoproteins,
proteoglycans, and some polysaccharides) causes the
injected animal's B lymphocytes to differentiate into
plasma cells and produce antibodies.
• Members of a lymphocyte clone (descendents of a single
lymphocyte) produce a single type of antibody, which
binds to a specific antigenic site, or epitope.
14. 1. Polyclonal antibodies: Large complex antigens may
have multiple epitopes and elicit several antibody types.
Mixtures of different antibodies to a single antigen are
called polyclonal antibodies.
2. Monoclonal antibodies: Antibodies specific for a single
epitope and produced by a single clone are called
monoclonal antibodies and are commonly raised in mice.
15. B. Labeling Antibodies:
• Antibodies are not visible with standard microscopy and
must be labeled in a manner that does not interfere with
their binding specificity.
• Common labels include fluorochromes (eg, fluorescein,
rhodamine), enzymes demonstrable via enzyme
histochemical techniques (eg, peroxidase, alkaline
phosphatase), and electron-scattering compounds for use
in electron microscopy (eg, ferritin, colloidal gold).
22. Part 1
1. Fixation
Fresh unfixed, fixed, or formalin fixation and
paraffin embedding
2. Sectioning
3. Whole Mount Preparation
Tissue preparation
23. Part 2
1. Antigen retrieval
Proteolytic enzyme method and Heat-induced method
2. Inhibition of endogenous tissue components
3% H2O2, 0.01% avidin
3. Blocking of nonspecific sites
10% normal serum
pretreatment
24. Part 3
• Make a selection based on the type of
specimen, the primary antibody, the degree
of sensitivity and the processing time required.
staining
25. • Positive Control
It is to test for a protocol or procedure used.
It will be ideal to use the tissue of known positive as a
control.
• Negative Control
It is to test for the specificity of the antibody involved.
Controls
