basics of stem cell transplant.ppt

Basics of Stem Cell Basics of Stem Cell TransplantTransplant

Dr. Akanksha Kushwah, Dr. Akanksha Kushwah, ResidentResident

PathologyPathology

BackgroundBackground

Hematopoietic stem cell transplantationHematopoietic stem cell transplantation– Intravenous infusion of autologous or Intravenous infusion of autologous or

allogeneic stem cellsallogeneic stem cells Collected from bone marrow, peripheral blood or Collected from bone marrow, peripheral blood or

umbilical cord bloodumbilical cord blood

– Re-establish hematopoietic function in Re-establish hematopoietic function in patients with damaged/defective bone patients with damaged/defective bone marrow or immune systemsmarrow or immune systems

– Potentially curative for a wide variety of Potentially curative for a wide variety of disordersdisorders

BackgroundBackground

First successful transplants—late First successful transplants—late 1960s1960s

30,000-40,000 transplants 30,000-40,000 transplants performed yearly worldwideperformed yearly worldwide

>20,000 patients have survived >20,000 patients have survived >5 years>5 years

TranplantTranplant

Patient's bone marrow stem cells Patient's bone marrow stem cells are replaced with healthy cells are replaced with healthy cells

Existing bone marrow and Existing bone marrow and abnormal leukocytes killedabnormal leukocytes killed

Chemotherapy and radiationChemotherapy and radiation Next bone marrow containing Next bone marrow containing

healthy stem cells re-infused healthy stem cells re-infused

Graft SourcesGraft Sources

Allogeneic: from another personAllogeneic: from another person Syngeneic: from an identical twinSyngeneic: from an identical twin Autologous: from the patientAutologous: from the patient

Choice of graft is based on Choice of graft is based on disease type, patient condition, disease type, patient condition, donor compatibility and healthdonor compatibility and health


Autologous TransplantAutologous Transplant– No evidence of disease in the blood No evidence of disease in the blood

or bone marrowor bone marrow– Transplant related mortality (TRM) Transplant related mortality (TRM)

lowest with autos (<5%)lowest with autos (<5%)– Relapse rates are higher depending Relapse rates are higher depending

on the diseaseon the disease– Absence of graft versus tumor effectsAbsence of graft versus tumor effects


Allogeneic TransplantsAllogeneic Transplants– High TRM (30-50%)High TRM (30-50%)– Lower relapse rates due to graft versus Lower relapse rates due to graft versus

tumor effect.tumor effect.– Graft versus host disease.Graft versus host disease.

Matched Related Donor (siblings)Matched Related Donor (siblings)– 25% chance a sibling will be a match25% chance a sibling will be a match– The more siblings a patient has the better The more siblings a patient has the better

chance for a matchchance for a match


Alternative DonorsAlternative Donors– Matched Unrelated Donors (MUD)Matched Unrelated Donors (MUD)

Severe GVHDSevere GVHD Higher TRMHigher TRM

– Haploidentical DonorsHaploidentical Donors From parent, child or siblingFrom parent, child or sibling Must have many stem cells to overcome risk of Must have many stem cells to overcome risk of

graft rejectiongraft rejection Increased risk of GVHDIncreased risk of GVHD

HLA TypingHLA Typing

HLA typing became feasible in HLA typing became feasible in 1960s1960s

Linked on chromosome 6Linked on chromosome 6 Inherited as haplotypesInherited as haplotypes 1 in 4 chance a sibling will be 1 in 4 chance a sibling will be

identicalidentical

HLA MatchingHLA Matching

There are 6 HLA markers that are matched.

For a successful transplant, at least 4 of these 6 markers must match.

HLA-A, HLA-B, HLA-C, HLA-DR, HLA-DQ, HLA-A, HLA-B, HLA-C, HLA-DR, HLA-DQ, HLA-DPHLA-DP

Haploidentical Haploidentical TransplantsTransplants A haploid-identical match is when

the donor is a parent and the genetic match is at least half identical to the recipient.

Parent, sibling or childParent, sibling or child High rate of engraftment failureHigh rate of engraftment failure GVHDGVHD

Indications Autologous Indications Autologous TransplantTransplant Multiple myelomaMultiple myeloma NHLNHL Hodgkin’s diseaseHodgkin’s disease AMLAML NeuroblastomaNeuroblastoma Ovarian cancerOvarian cancer Germ-cell tumorsGerm-cell tumors

Autoimmune Autoimmune disordersdisorders

AmyloidosisAmyloidosis

Indications for Indications for Allogeneic TransplantAllogeneic Transplant AMLAML ALLALL CMLCML MDSMDS MPDMPD NHLNHL Hodgkin’s DiseaseHodgkin’s Disease CLLCLL Multiple myelomaMultiple myeloma Juvenile CMLJuvenile CML

Aplastic anemiaAplastic anemia PNHPNH Fanconi’s anemiaFanconi’s anemia Blackfan-DiamondBlackfan-Diamond Thalessemia majorThalessemia major Sickle cell anemiaSickle cell anemia SCIDSCID Wiskott-AldrichWiskott-Aldrich Inborn errors of Inborn errors of

metabolismmetabolism

Hematopoietic Hematopoietic Progenitor Cell Progenitor Cell SourcesSources

Bone MarrowBone Marrow PBSC (peripheral blood stem PBSC (peripheral blood stem

cells)cells) Umbilical CordUmbilical Cord

Peripheral blood stem Peripheral blood stem cellscells Autologous transplants rely almost Autologous transplants rely almost

exclusively on PBSC rather than marrow exclusively on PBSC rather than marrow due to: due to:

Easier collection of cells Easier collection of cells More rapid hematopoietic recovery More rapid hematopoietic recovery Decreased costs Decreased costs

PBSCPBSC

Most blood stem cells reside in the Most blood stem cells reside in the bone marrow and a small number bone marrow and a small number are present in the bloodstream are present in the bloodstream

Multipotent peripheral blood stem Multipotent peripheral blood stem cellscells

Can be obtained from drawn bloodCan be obtained from drawn blood PBSCs are easier to collect than PBSCs are easier to collect than

bone marrow stem cells bone marrow stem cells

Adult Stem Cell Adult Stem Cell Transplant Transplant

Umbilical Cord BloodUmbilical Cord Blood

Physicians may consider umbilical cord Physicians may consider umbilical cord blood a good choice particularly for patients blood a good choice particularly for patients who need an unrelated donor and have an who need an unrelated donor and have an uncommon HLA type or are in urgent need uncommon HLA type or are in urgent need of a transplant. of a transplant.

HLA mismatch is better tolerated – even HLA mismatch is better tolerated – even with haploidentical donorswith haploidentical donors

Available more quickly than marrow or Available more quickly than marrow or PBSC unrelated donorsPBSC unrelated donors

Reduced incidence and severity of GVHDReduced incidence and severity of GVHD


11stst UCB transplant 16 years ago UCB transplant 16 years ago – Child with Fanconi’s anemiaChild with Fanconi’s anemia

Cell dose is given per recipient weightCell dose is given per recipient weight– Lower patient weights the high the cell doseLower patient weights the high the cell dose– 2 x 102 x 1077 nucleated cells/kg nucleated cells/kg– 1.7 x 101.7 x 1077 CD 34+ cells/kg CD 34+ cells/kg

4/6 match UCB with sufficient cells has 4/6 match UCB with sufficient cells has a similar outcome to a matched or one a similar outcome to a matched or one antigen mismatched matched unrelated antigen mismatched matched unrelated donor (MUD).donor (MUD).


Lower GVHDLower GVHD TRM not different than MUDTRM not different than MUD Can be used with myeloablative Can be used with myeloablative

or nonmyeloablative conditioning or nonmyeloablative conditioning (on a clinical trial)(on a clinical trial)

Transplant Process (5 Transplant Process (5 steps)steps)

(1) Conditioning, (1) Conditioning,

(2) Stem cell infusion, (2) Stem cell infusion,

(3) Neutropenic phase, (3) Neutropenic phase,

(4) Engraftment phase(4) Engraftment phase

(5) Post-engraftment period. (5) Post-engraftment period.

Conditioning PhaseConditioning Phase

The conditioning period typically lasts 7-The conditioning period typically lasts 7-10 days.10 days.

The purposes are (by delivery of The purposes are (by delivery of chemotherapy and/or radiation)chemotherapy and/or radiation)– to eliminate malignancyto eliminate malignancy– to provide immune suppression to prevent to provide immune suppression to prevent

rejection of new stem cells rejection of new stem cells – create space for the new cellscreate space for the new cells

Radiation and chemotherapy agents Radiation and chemotherapy agents differ in their abilities to achieve these differ in their abilities to achieve these goals.goals.

Collection of Stem Collection of Stem CellsCells Bone Marrow HarvestBone Marrow Harvest

– General anesthesiaGeneral anesthesia– Equivalent of 50-100 bone marrow Equivalent of 50-100 bone marrow

biopsiesbiopsies– Used much less oftenUsed much less often– 2 deaths in 8000 collections2 deaths in 8000 collections

Collection of Stem Collection of Stem CellsCells Stem Cell Collection (mobilization)Stem Cell Collection (mobilization)

– Stem cells circulate in the bloodStem cells circulate in the blood– Identified by CD34+ by flow cytometryIdentified by CD34+ by flow cytometry– Stem cells are collected through an Stem cells are collected through an

apheresis catheterapheresis catheter– More cells are collectedMore cells are collected– Higher chronic GVHD than bone marrow Higher chronic GVHD than bone marrow

harvestharvest– More rapid marrow recoveryMore rapid marrow recovery

Collection of Stem Collection of Stem CellsCells Harvesting stem cells from the blood stream

is accomplished by a process called apheresis.

The patient is connected to a cell separation machine via a needle in each arm. Blood is taken from one arm, circulated through the machine to remove the stem cells, and the remaining blood cells are returned to the patient through the other arm.

Several sessions of up to six hours are required to harvest, through apheresis, enough stem cells for transplantation

COBE Spectra Apheresis System

Infusion of Stem CellsInfusion of Stem Cells

Stem cells may be infused fresh Stem cells may be infused fresh within a few hours of collectionwithin a few hours of collection

May be frozen using dimethyl May be frozen using dimethyl sulfoxide.sulfoxide.

Umbilical cord blood is obtained Umbilical cord blood is obtained from one of the umbilical cord from one of the umbilical cord veins and frozen with an veins and frozen with an anticoagulant and nutrient mediaanticoagulant and nutrient media

Stem cell processing Stem cell processing and infusionand infusion Infused through a CVL, much like a blood Infused through a CVL, much like a blood

transfusion. transfusion. Anaphylaxis, volume overload, and a Anaphylaxis, volume overload, and a

(rare) transient GVHD (rare) transient GVHD are the major are the major potential complications involved. potential complications involved.

Stem cell products that have been Stem cell products that have been cryopreserved contain dimethyl sulfoxide cryopreserved contain dimethyl sulfoxide (DMSO) as a preservative and potentially (DMSO) as a preservative and potentially can cause renal failure, in addition to the can cause renal failure, in addition to the unpleasant smell and taste(Creamed corn unpleasant smell and taste(Creamed corn or garlic smell)or garlic smell)

Stem Cell ManipulationStem Cell Manipulation

ABO incompatibleABO incompatible– Removal of isoagglutinins or RBCsRemoval of isoagglutinins or RBCs

T-cell depletionT-cell depletion– Reduce incidence of GVHDReduce incidence of GVHD– Increased graft failureIncreased graft failure– Increased relapse ratesIncreased relapse rates

In vitro purgingIn vitro purging– Removal of tumor cellsRemoval of tumor cells– Positive selection of CD34+ cellsPositive selection of CD34+ cells

Neutropenic PhaseNeutropenic Phase

During this period (2-4 wk), the patient During this period (2-4 wk), the patient essentially has no effective immune essentially has no effective immune system. system.

Healing is poor, and the patient is very Healing is poor, and the patient is very susceptible to infection. susceptible to infection.

Supportive care and empiric antibiotic Supportive care and empiric antibiotic therapy are the mainstays of therapy are the mainstays of successful passage through this phasesuccessful passage through this phase..

Recovering from the Recovering from the transplanttransplant Engraftment PhaseEngraftment Phase

Recovery of normal levels cells is called Recovery of normal levels cells is called engraftmentengraftment

Day 8 - 12 Day 8 - 12 Neutrophil engraftment important (GCSF) Neutrophil engraftment important (GCSF)

may be given to accelerate the processmay be given to accelerate the process Platelets are the next to return with red cells Platelets are the next to return with red cells

last.last. Commonly patients require transfusion of red Commonly patients require transfusion of red

cells and platelets following a transplant.cells and platelets following a transplant. Discharge upon neutrophil & platelet Discharge upon neutrophil & platelet

engraftmentengraftment

Engraftment PhaseEngraftment Phase

During this period (several weeks), the During this period (several weeks), the healing process begins with resolution healing process begins with resolution of mucositis and other lesions of mucositis and other lesions acquired. In addition, fever begins to acquired. In addition, fever begins to subside, and infections often begin to subside, and infections often begin to clear. The greatest challenges at this clear. The greatest challenges at this time are management of GVHD and time are management of GVHD and prevention of viral infections prevention of viral infections (especially CMV). (especially CMV).

Post-engraftment Post-engraftment PhasePhase This period lasts for months to This period lasts for months to

years. Hallmarks of this phase years. Hallmarks of this phase include the gradual development include the gradual development of tolerance, weaning off of of tolerance, weaning off of immunosuppression, immunosuppression, management of chronic GVHD, management of chronic GVHD, and documentation of immune and documentation of immune reconstitution.reconstitution.

Auto TransplantAuto Transplant

AllotransplantAllotransplant

Post Stem Cell Transplant Monitoring

The role of the laboratory in post stem cell transplant monitoring is to provide clinicians with accurate information of the engraftment status by quantitatively determining the proportion of donor and recipient derived cells in the patient post transplant.

Most laboratories use Short Tandem Repeats (STR’s) for this.

Post Stem Cell Transplant Monitoring

Post stem cell transplant chimerism results are typically reported as % donor chimerism.

A 100% donor chimera implies complete engraftment.

A 0% donor chimerism implies no donor engraftment with all other percentages reported as mixed chimerism showing the proportion of donor engraftment.

ComplicationsComplications

EarlyEarly– MucositisMucositis– Sinusoidal obstructive syndrome Sinusoidal obstructive syndrome

(VOD)(VOD) Fluid retention, jaundice, hepatomegalyFluid retention, jaundice, hepatomegaly

– Transplant related infectionsTransplant related infections Damage to mouth, gut and skinDamage to mouth, gut and skin Prolonged neutropeniaProlonged neutropenia


EarlyEarly– PancytopeniaPancytopenia

PRBC and platelet transfusionsPRBC and platelet transfusions Broad spectrum antimicrobialsBroad spectrum antimicrobials Antifungals if prolonged fevers 3-5 daysAntifungals if prolonged fevers 3-5 days

Graft versus Host Disease (GVHD)

• GVHD sometimes occurs with allogeneic transplantation.

• Lymphocytes from the donor graft attack the cells of the host

• GVHD can usually be treated with steroids or other immunosuppressive agents.

• Acute GVHD occurs before day 100 post-transplant

• Chronic GVHD occurs beyond day 100 • Chronic GVHD can develop months or even

years post-transplant


EarlyEarly– Graft RejectionGraft Rejection

Host versus graftHost versus graft Drug injury to marrowDrug injury to marrow Viral infections: CMV, HHV-6 & 8Viral infections: CMV, HHV-6 & 8

– Interstitial PneumonitisInterstitial Pneumonitis Diffuse alveolar hemorrhageDiffuse alveolar hemorrhage Too few donor stem cellsToo few donor stem cells ARDS often caused by CMVARDS often caused by CMV


DelayedDelayed– Chronic GVHDChronic GVHD

Scleroderma or Sjogrens syndromeScleroderma or Sjogrens syndrome BronchiolitisBronchiolitis KeratoconjunctivitisKeratoconjunctivitis MalabsorptionMalabsorption CholestasisCholestasis Esophageal strictureEsophageal stricture

Late ComplicationsLate Complications

Secondary TumorsSecondary Tumors– Acute leukemias, solid tumors, MDSAcute leukemias, solid tumors, MDS– Months to years after transplantMonths to years after transplant– Increased incidence with TBIIncreased incidence with TBI

Late InfectionsLate Infections– Bacterial, viral, fungalBacterial, viral, fungal– Months after transplantMonths after transplant– Associated with GVHDAssociated with GVHD– Need repeat vaccinationsNeed repeat vaccinations

Pneumovax, Hep B, Hemophilus influenza b, Pneumovax, Hep B, Hemophilus influenza b, poliovirus, diphtheria/tetanus, flupoliovirus, diphtheria/tetanus, flu

SourceSource

basics of stem cell transplant.ppt

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