RBC - SICKLE SHAPED

1. SICKLE CELL ANAEMIA
Dr. Esther Shoba R
Assistant Profesor
Kristu Jayanti College

2. SICKLE CELL ANAEMIA
INHERITED blood disorder – abnormal haemoglobin, haemoglobin S ,
sickle haemoglobin S
Hemoglobin is a protein in red blood cells that carries oxygen throughout
the body
When a person has two hemoglobin S genes, Hemoglobin SS, the disease
is called sickle cell anemia
 Hb S: Linus Pauling et.al., 1949
 Prdn of Abnormal Protein is because of Genetic disorder
 6Glu→Val - Vernon Ingram (1956)
 1960s, 1970s : first coherent pathophysiological scheme - abnormal
polymerization of deoxy-HbS elaborated

5. This condition is inherited in an autosomal recessive pattern, which means both
copies of the gene in each cell have mutations. The parents of an individual with an
autosomal recessive condition each carry one copy of the mutated gene, but they
typically do not show signs and symptoms of the condition.

7. Symptoms
• Signs and symptoms vary from people to people
• Anemia - Normal RBC - 120 days, sickle RBC - 10 to 20 days, no energy and thus
fatigue
• Epidoses of pain - Pain develops when sickle-shaped red blood cells block blood flow
through tiny blood vessels to your chest, abdomen and joints. Pain can also occur in
bones. (Vaso-occlusive painful crisis (VOC)
• Painful swelling of hands and feet - The swelling is caused by sickle-shaped red blood
cells blocking blood flow to the hands and feet
• Frequent infections - Sickle cells can damage an organ that fights infection (spleen)
• Delayed growth - Red blood cells provide your body with the oxygen and nutrients
you need for growth. A shortage of healthy red blood cells can slow growth in infants
and children and delay puberty in teenagers.

8. • Vision problems. Tiny blood vessels that supply your eyes may become
plugged with sickle cells. This can damage the retina — the portion of
the eye that processes visual images, leading to vision problems
• Severe Anaemia
• Fatigue, paleness, rapid heart rate, shortness of breath (sickle cells
block lungs)
• Jaundice – Pale skin or nail beds
• Yellow tint to the skin and whites of the eyes
• Problems with thinking or confusion caused by small strokes
• Ulcers on the lower legs (in adolescents and adults)
Bone infection (osteomyelitis), Gallbladder infection (cholecystitis),
pneumonia, UTI

10. LABORATORY DIAGNOSIS
1. HiCN Method – Drabkin’s solution
Exception - Pregnant women, haemodilution > 10.5g/dl
2. Haematorit or Packed cell volume - it is the amount of packed red
blood cell, following centrifugation, expressed as a t otal
Normal Value - male: 42-52%
Female:: 36-49%
3.Peripheral blood film examination- Normal RBC – biconcave, 7.2µm,
thickness 2.4µm and 1 µm in the centre. Biconcave shape render the
cell flexible to pass through capillaries which are about 3.5µm

13. TREATMENT
• NIH – National Institute of health advices optimal care of patients
• Self treatment – bed rest, oral analgesia and hydration
• Long term transfusion therapy to prevent stroke
• Initiation of opoids for vaso-occlusive crisis
• FDA has approved ingestion of L- glutamine oral powder. This reduced pain crisis
that resulted in treatment
• Hydroxyurea therapy
FDA has approved this therapy for long term treatment. This increases total and
fetal hemoglobin.
• Transfusion
• Urgent replacement of blood is often required for sudden, severe anemia due to
acute splenic sequestration, parvovirus B19 infection, or hyperhemolytic crisis.
Transfusion is helpful in acute chest syndrome, perioperatively, and during
pregnancy.

14. Bone Marrow Transplantation: The Only Cure:
• Currently the cure for sickle cell disease is bone marrow
transplantation. In this procedure a sick patient is transplanted with
bone marrow from healthy, genetically compatible sibling donors.
However only about 18 percent of children with sickle cell disease
have a healthy, matched sibling donor. Bone marrow transplantation
is a risky procedure with many complications.

15. GENE THERAPY for sickle cell anaemia
 Researchers at UCLA’s Eli & Edythe Broad Center of Regenerative Medicine &
Stem Cell Research have successfully established the foundation for using
hematopoietic (blood-producing) stem cells (HSC) from the bone marrow of
patients with sickle cell disease (SCD) to treat the disease. The study was led
by Dr. Donald Kohn, professor of pediatrics and microbiology, immunology and
molecular genetics in the life sciences.
 Patient treated with lentiviral vector–mediated addition of an antisickling β-
globin gene into autologous hematopoietic stem cells. Fifteen months after
treatment, the level of therapeutic antisickling β-globin remained high
(approximately 50% of β-like–globin chains) without recurrence of sickle crises
and with correction of the biologic hallmarks of the disease

16. • HSC
• insert gene with ant sickling property
• Transduce into the patients bone marrow using lentiviral vector
• Now a team in France seems to have developed a treatment
• bone marrow stem cells were taken
• gave extra, mutated versions of the gene that codes for beta-globin.
These were designed to make beta-globin that would interfere with the
faulty proteins, stopping them from clumping together.
• The researchers then put these stem cells back into the body. After
around three months, he began producing large quantities of
haemoglobin that behaves normally (New England Journal of
Medicine, DOI: 10.1056/NEJMoa1609677). “The patient is now 15 years
old and free of all previous medication

17. Von GIERKE disease
• Also known as GSDI – glycogen storage disease type
•
• An inherited disorder that builds up glycogen in body cells
• Organs and tissues - liver, kidneys and small intestines and thus
impairs their function
• Seen at 3-4 months of baby when they don’t take feed normally at
nights
• Frequency - 1 in 1,00,000 where GSDIa is dominant as compared to
GSDIb

19. Etiology
• Mutation s in gene G6PC (GSDIa) and SLC37A4 (GSDIb)
• G6PC gene codes for Glucose - 6 – phophatase (enzyme present on
membrane of ER) together with
• SLC37A4 codes for - solute carrier family 37 member 4, which function
as glucose 6-phosphate translocase protein
• This two work together to break glucose -6-phosphate
• If glucose -6-phosphate is not broken down they convert to glycogen
an fat, this becomes toxic and damages organs and tissues (liver and
kidney)
• Atleast 85 mutations are reported in G6PC gene

21. SLC37A4 gene - solute carrier family 37 member 4
The SLC37A4 gene provides instructions for making a protein called
glucose 6-phosphate translocase
This protein transports the sugar molecule glucose 6-phosphate from the
fluid inside the cell to the endoplasmic reticulum, which is a structure
inside cells that is involved in protein processing and transport
At the membrane of the endoplasmic reticulum, glucose 6-phosphate
translocase works together with the glucose 6-phosphatase protein
(produced from the G6PC gene) to break down glucose 6-phosphate
If glucose 6-phosphate cannot get to the endoplasmic reticulum, it
cannot get broken down and glucose is not produced
More than 80 mutations

25. INHERITANCE PATTERN
• This condition is inherited in an autosomal recessive pattern, which
means both copies of the gene in each cell have mutations.
• The parents of an individual with an autosomal recessive condition
each carry one copy of the mutated gene, but they typically do not
show signs and symptoms of the condition.
• That is parents should be carriers

26. Symptoms
• Seen at 3-4 months of baby when they don’t take feed normally at nights
• Affected infants have low blood sugar that leads to seizures
• More of lactic acid, uric acid and excess amount to fats
• As they get older, children with GSDI have thin arms and legs and short
stature
• An enlarged liver may give the appearance of a protruding abdomen
• The kidneys may also be enlarged
• Delayed puberty because of abnormal development of the ovaries –
polycystic ovaries
• Adenomas (tumor) form in the liver, may be noncancerous (benign) or
cancerous (malignant)

27. Symptoms
• Researchers have described two types of GSDI, which differ in their signs
and symptoms and genetic cause
• These types are known as glycogen storage disease type Ia (GSDIa) and
glycogen storage disease type Ib (GSDIb)
• People with GSDIb have neutropenia (less WBC), so more infections,
inflammation of intestinal walls, inflammation of the gums (gingivitis),
chronic gum (periodontal) disease, abnormal tooth development, and
open sores (ulcers) in the mouth
• The neutropenia and oral problems are specific to people with GSDIb
and are typically not seen in people with GSDIa

28. LABORATORY DIAGNOSIS

29. LABORATORY DIAGNOSIS
• Molecular Genetics Tests
• Targeted variant analysis (14)
• Deletion/duplication analysis (22)
• Sequence analysis of select exons (2)
• Mutation scanning of the entire coding region (1)
• Sequence analysis of the entire coding region (39)

30. TREATMENT

31. Treatment - Gene therapy
Adenovirus- and adeno-associated virus (AAV)-mediated gene
therapies have been evaluated for GSD-Ia in these model systems.
adenoviral therapy produces only short term corrections and only
impacts liver expression of the gene
AAV-mediated therapy delivers the transgene to both the liver and
kidney, achieving longer term correction of the GSD-Ia disorder
Gene therapy for GSD-Ib in the animal model is still in its infancy,
although an adenoviral construct has improved the metabolic profile
and myeloid function.
Initial studies using Adeno associated virus (AAV) serotype 2–based
vectors expressing G6Pase-α to treat infant GSD-Ia in dogs or mice
showed suboptimal improvement
Adeno associated virus (AAV) serotype 8 vectors are also used

32. Treatment - Gene therapy
• Correct gene in vectors of feline immunodeficiency virus (FIV), a
nonprimate lentivirus and transduced in the liver of the murines
• these vectors are capable of integrating stably into hepatocyte cell
lines and adult murine livers and lead to long-term transgene
expression
• Single administration of FIV vectors containing the human G6Pase
gene to G6Pase-α−/− mice did not change the biochemical and
pathological phenotype
• However, a double neonatal administration protocol led to
normalized blood glucose levels, significantly extended survival,
improved body weight, and decreased accumulation of liver glycogen
associated with the disease