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Therapeutic Haemapheresis

Apheresis Department of the IHBT - therapeutic and cell production hemapheresis (apheresis)

The procedures are performed using the hemapheresis technique on blood component separators, which usually use the centrifugation principle.

  • Therapeutic haemapheresis The aims of therapy are to reduce the content of multiplied blood or pathogenically active components in the patient's circulation.
  • Production apheresis with collection of cells for transplantation and haemopoietic reconstitution

Separation of peripheral blood hematopoietic cells from mobilized donors and patients for elective allogeneic and autologous transplantation. The procedures are performed in standard or high-volume mode when more than three volumes of donor or patient blood are processed. Separation of allogeneic mononuclear cells by adoptive immunotherapy (DLI) from non-mobilized donors. Long-term monitoring of donor safety after donor mobilization and cell separation at the facility.

  • Separation of autologous mononuclear cells for individualised anti-cancer therapy, e.g. for the preparation of CAR-T lymphocytes.
  • Safety of therapeutic and production cell haemapheresis
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Therapeutic haemapheresis

  1. Depletion leukocyte apheresis (white blood cell collection, leukocyte separation/depletion)

A therapeutic procedure used to rapidly reduce the content of multiplied white blood cells in the patient's circulation. On a separator, white blood cells are separated from other blood components and removed into a collection bag. The procedure is performed in hyperleukocytic patients with acute or chronic leukemia. is most often indicated in patients with acute or chronic myeloid leukemia who have a leukocyte count greater than 100×109/l, who show signs of leukostasis and hyperviscosity of the blood.

  1. Depletion thrombocytapheresis is performed in patients with platelet counts higher than 1000×109/l, e.g. in chronic myeloid leukaemia (CML) and other myeloproliferative diseases (essential thrombocythaemia, primary polycythaemia and myelofibrosis).
  2. Depletion erythrocytapheresis allows reduction of the multiplied erythrocyte content in primary polycythemia. It is also an effective procedure for the removal of excess iron in chronic iron overload conditions such as haemochromatosis and secondary haemosiderosis. The procedure is suitable in situations where a large erythrocyte content needs to be rapidly removed from the patient's circulation. Erythrocytapheresis is more effective than therapeutic venepuncture and does not result in loss of plasma proteins, platelets and granulocytes.
  3. Erythrocytapheresis (red blood cell exchange, erythrocyte exchange)

A medical procedure used to rapidly remove abnormal red blood cells from a patient's circulation and replace them with red blood cells from healthy donors. It is used, for example, in the treatment of sickle cell anaemia, in which large numbers of abnormal red blood cells can be removed from the circulation of patients with sickle cell anaemia or malaria and replaced with red blood cells from healthy donors.

  1. Exchange (therapeutic) plasmapheresis

During the procedure, a large volume of plasma is effectively removed from the patient's bloodstream and replaced with plasma, Octaplas (mixed plasma treated to inactivate pathogens, filtered), albumin solution, or a combination of crystalloid and colloid solutions. Autoimmune antibodies (IgM or IgG), alloprotibodies, circulating immunocomplexes, paraproteins (hyperviscosity syndrome, cryoglobulinemia), inhibitors of coagulation factors (f. VIII), enzymes (TTP- thrombotic thrombocytopenic purpura) are removed with plasma.

  1. Extracorporeal immunoadsorption

More and more efficient separation techniques are being developed, using more selective procedures to reduce the content of pathogenic components in the circulation, as in extracorporeal immunoadsorption. These techniques use chemical, physical or immunological principles. First, plasma is separated from the patient's circulation using haemapheresis techniques (centrifugation or filtration). The plasma then passes through an immunoadsorption column, in which the pathogenic component - usually IgG or LDL - is adsorbed and then remains bound to the column, while the treated plasma is returned to the patient's circulation. These procedures can remove approximately 80-90% of the smaller molecule substances from the circulation. Unlike exchange plasmapheresis, this technique is more efficient and there is no need to substitute the collected plasma with replacement solutions or plasma from healthy donors. It is indicated in the treatment of patients with autoimmune diseases refractory to standard therapy or severe familial disorders of lipid metabolism. It is the only treatment option for hypercholesterolaemia in patients who do not respond to dietary, regimen and pharmacological treatment. IgG separation is of great importance in reducing the levels of autoimmune antibodies against the acetylcholine receptor type IgG in myasthenia gravis or against factor VIII in haemophilia A.

  1. Extracorporeal photochemotherapy (ECP, photopheresis) A treatment procedure that affects the reactivity of the immune system but does not induce generalized immunosuppression. ECP is indicated in the therapy of diseases whose pathogenesis involves T lymphocytes, such as graft-versus-host disease (GVHD) and therapy of cutaneous T lymphomas.

First, mononuclear cells (lymphocytes and monocytes, hereafter MNCs) are removed from the patient's blood using the leukocytapheresis technique. The MNCs are then photomodified using the photosensitizing agent 8-methoxypsoralen and ultraviolet A radiation.

  1. Extracorporeal hemorheopheresis is an effective form of extracorporeal membrane differential filtration of plasma that allows the elimination of high molecular weight substances such as fibrinogen, and 2-macroglobulin, immunoglobulin M (IgM), thrombomodulin, and LDL lipoproteins. The technique is an effective therapeutic modality in the treatment of patients with microcirculation disorders, which include age-related macular degeneration (AMD).

The procedure is performed using a double filtration technique - blood and plasma. First, plasma is separated from the patient's whole blood, which is then passed through a second filter to remove high molecular weight substances. Among the biochemical parameters monitored, according to our results, there is a decrease in the level of alpha2-macroglobulin (69%), IgM (67%), LDL cholesterol (58%) and fibrinogen (54%). The content of low molecular weight substances in serum does not change significantly (minerals, total protein and albumin, glucose).

  • Production apheresis with cell collection for transplantation and haemopoietic reconstitution
  • Peripheral blood hematopoietic cell separation (PBPC, PBSC - Peripheral Blood Progenitor Cells, Peripheral Blood Stem Cells)

The procedure is performed on both healthy donors (PBPC for allogeneic transplantation) and patients (PBPC for autologous transplantation). PBPCs express the glycoprotein CD34 on their surface, which can be detected by flow cytometry. Mobilisation of haematopoietic precursors from the bone marrow into the peripheral blood is required before PBPC collection in donors and patients. Autologous PBPCs are prepared for the therapy of patients with hematological malignancies or autoimmune diseases. Allogeneic PBPCs are prepared for the therapy of patients with haematological malignancies, bone marrow failure, immunodeficiency syndromes and inborn errors of metabolism. In patients after high-dose or myeloablative chemotherapy, PBPCs are able to provide restoration of hemopoietic and immune functions.

Under normal conditions, only a very small number of haematopoietic cells are found in the blood. This amount of cells would not be sufficient to restore the hematopoietic and immune functions of the patient. Therefore, prior to PBPC collection from donors and patients, hematopoietic cell mobilization from the bone marrow into the peripheral blood is performed. Patients in mobilization preparation are usually given a combination of chemotherapy and growth factors. Donors are mobilised with growth factors only. Chemotherapy is not given to donors.

Sometimes mobilisation fails, only a small number of haematopoietic cells are flushed out of the bone marrow and the required dose cannot be obtained by the separation technique. It has been reported that approximately 5% of healthy donors fail to mobilise haematopoietic cells from the bone marrow into the blood. In patients whose mobilization efficiency is additionally influenced by the underlying disease and the extent of previous chemotherapy/ actinotherapy, mobilization failure occurs more frequently in up to 30% of cases.

The hematopoietic cell engraftment time after transplantation is defined as a rise in neutrophil leukocyte count above 0.5×109/l or platelet count above 20 or 50×109/l, respectively. Engraftment usually occurs between days 12 and 14 after transfer. This time is significantly shorter compared to the healing time of hematopoietic cells from bone marrow, which occurs between 20 and 30 days.

Separation of haematopoietic cells from peripheral blood

PBPC separations are performed

  1. in a standard regimen in which 2 to 3 total volumes of patient blood are processed or
  2. in the bulk mode, where more than 3 volumes of the patient's blood are processed.

The procedures vary not only in volume but also in anticoagulation procedures and flow rates. High-volume procedures allow higher doses of CD34+ cells to be obtained than standard procedures in both donors and patients. In well-mobilized patients and donors, one to two procedures can be used to prepare the necessary amount of CD34+ cells for transplantation. The time per procedure ranges from 3 to 5 hours.

Standard and high-volume separations are among the more technically demanding haemapheresis procedures. During these procedures, large volumes of blood are processed and higher doses of anticoagulant solutions are administered than in other procedures. Anticoagulants act either predominantly in the extracorporeal circuit (ACD-A) or agents with systemic effects (heparin) are added to the separation circuit. During the procedure, significant decreases in blood count parameters, plasma mineral levels and coagulation results may occur.

  1. Allogeneic preparations for adoptive immunotherapy - for infusion of mononuclear cells

to induce the Graft vs. Leukemia effect. This group includes the preparation of mononuclear cell concentrates - lymphocytes and monocytes () for (Donor Lymphocyte Infusion).

Mononuclear cells are separated from a healthy donor who has previously donated hematopoietic cells (PBPC) to a patient for allogeneic transplantation. If the patient develops a relapse of the underlying disease after the transplant, the same donor donates mononuclear cells that are able to induce a graft-versus-leukaemia (GVL) response and suppress the relapse.

The donors are no longer mobilised before the actual collection of the cells. During the procedure, one to two times the donor's blood volume is processed. The goal is to prepare a concentrate with a CD3+ T-lymphocyte content usually in the range of 1×107 to 5×108/kg of recipient weight. The choice of dose depends on the underlying disease and the patient's condition.

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  • Separation of autologous mononuclear cells for individualized anti-cancer therapy
  • Autologous mononuclear cells for the preparation of CAR-T lymphocytes

First, autologous non-mobilized mononuclear cells (lymphocytes and monocytes, MNCs) are separated using the leukocytapheresis technique to prepare CAR-T lymphocytes. The procedure represents an effective therapy for patients with CD 19 relapsed or refractory Non-Hodgkin's lymphomas - DLBCL, MCL, FL. It can be effective in B-ALL or MM (multiple myeloma). After separation, MNC cells are transported to the processor's laboratories where they are genetically modified, usually using a lentiviral vector. The cells are injected with the genetic code for an anti CD 19 chimeric antigen receptor specific for the recognition of the CD 19 antigen on tumour cells. CAR T lymphocytes, when administered to a patient, are able to specifically recognize and bind the antigen on the surface of tumor cells and activate the T lymphocytes to induce a cytotoxic effect. In recent years, the efficacy of CAR-T lymphocyte therapy has also been investigated in some autoimmune diseases, such as SLE (systemic lupus erythematosus and others).

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  1. Safety of therapeutic hemapheresis

Although therapeutic hemapheresis is considered a safe procedure, adverse reactions can occur during the procedure. During separations, fluid shifts between the intravascular and extravascular spaces, changes in plasma mineral levels, changes in coagulation factors and immunoglobulin levels occur.

Patients are at increased risk of adverse reactions:

  • with disorders of the cardiorespiratory system with unstable vital functions,
  • in intensive care,
  • anaemia and thrombocytopenia,
  • with bleeding complications,
  • treated with ACE inhibitors,
  • with allergies,
  • history of post-transfusion reactions,
  • pregnant patients.

Patients may be unconscious (e.g., at ), on oxygen therapy, or on ventilatory support. They may have signs of organ failure. In such situations, it is necessary to ensure continuation of vital support and other intensive care during the procedure.

During more demanding procedures, such as large-volume PBPC separations, significant changes in serum mineral levels may occur (decreases in K+, Mg++, Ca++) and coagulation and blood count parameters may be significantly affected. Hypokalaemia of the patient can be dangerous even with a slight decrease in plasma potassium levels, especially if the patient is concurrently treated with drugs that sensitise the myocardium, e.g. digoxin. Alkalosis potentiates the effect of hypokalaemia and the administration of glucose and insulin has a similar effect.

During exchange therapies, patients receive transfusions that may be accompanied by post-transfusion reactions. Large volumes of plasma (whole blood plasma, apheresis plasma, cryosupernatant plasma or solvent detergent plasma - Octaplas) are repeatedly transfused during exchange therapy and HUS. Erythrocyte preparations are administered in large quantities and repeatedly during exchange erythrocyte apheresis in patients with malaria or sickle cell anaemia. Erythrocytes are also used to prefill the device when performing therapeutic haemapheresis in children. It is advisable that the erythrocyte preparations are not older than 7 days.

For planned procedures, it is advisable to ensure adequate preparation of the patient in advance - to verify or prepare a suitable venous access, to ensure minimum blood count values (haematocrit at least 21% - preferably at least 24%, platelets higher than 50×109/l), to verify the status of the cardiorespiratory system, renal and hepatic functions, mineralogram and coagulation parameters - aPTT and Quick, fibrinogen level. It is not advisable for the patient to be on concomitant therapy with ACE inhibitors during the procedure because of the increased risk of severe hypotensive-anaphylactoid reactions (activation of the kallikrein-kinin system and bradykinin production). Vital signs should be monitored during the procedure, especially in clinically unstable patients. During the procedure, donors and patients are under constant supervision of a nurse and a physician.

Adverse reactions usually occur in between 3 and 25% of procedures. Most of the complications are related to the lack of venous access or to the clinically unstable condition of the patient. The separation process itself causes adverse reactions in a smaller number of cases, approximately 1-11% of procedures. Reactions are usually less severe and can be successfully resolved without premature termination of the procedure, e.g. hypocalcemia or mild hypotensive reactions of the patient. However, very rarely, serious complications have been described - as a result of bleeding, cardiopulmonary failure, TRALI syndrome or in connection with the development of a severe hypotensive-anaphylactoid reaction in patients treated with ACE inhibitors.