Christopher D. Hillyer

Increase in circulating colony-forming units-granulocyte-macrophage during large-volume leukapheresis: evaluation of a new cell separator

Peripheral blood stem cell (PBSC) collection was evaluated in two groups of normal donors who underwent large‐volume leukapheresis on a blood cell separator. In Group A (n = 10), a 3‐hour leukapheresis was performed. An average of 11.8 L of blood was processed with a mean flow rate of 66 mL per minute and a collection rate of 3 mL per minute. The PBSC product contained a mean 1.4 × 10(10) mononuclear cells (MNCs) (lymphocytes and monocytes), 1.27 × 10(6) colony‐forming units‐ granulocyte‐macrophage (CFUs‐GM), and an average hematocrit of 4 percent (0.04). Postapheresis blood counts showed significant reductions in MNCs (19%) and platelets (45%) (p < 0.005). Twenty‐four hours later, the MNCs had returned to preapheresis levels. The platelet count returned to baseline only after 7 days. Circulating CFUs‐GM remained stable for 3 days after apheresis but were increased twofold by Day 7 after apheresis (p = 0.025). Varying the product hematocrit from 1 percent (0.01) to 13.3 percent (0.13) did not change the number of CFUs‐GM collected per MNC. In Group B (n = 4), an average of 18.5 L of blood was processed with a mean flow rate of 94 mL per minute and a collection rate of 3 mL per minute. The PBSC product was collected as four sequential samples and assayed for MNCs and CFUs‐GM. Total MNCs averaged 1.7 × 10(10) (an increase of 21% relative to Group A) and CFUs‐GM averaged 3.08 × 10(6) (an increase of 143%). Mean MNCs did not vary significantly among the four samples. However, CFUs‐GM collected per minute (relative to the first sample) did show 1.26‐fold (p = 0.001), 1.86‐fold (p = 0.011), and 2.52‐fold (p = 0.04) increases in the second, third, and fourth samples. These data suggest that MNCs and committed progenitor cells are recruited during large‐volume leukapheresis. Moreover, there is a twofold increase in circulating CFUs‐GM 1 week after apheresis.

The risk of cytomegalovirus infection in solid organ and bone marrow transplant recipients: transfusion of blood products

CYTOMEGALOVIRUS (CMV) INFECTION is transmitted by blood transfusion from seropositive (CMV antibodypositive) donors and generally ranges in the normal host from asymptomatic seroconversion to mild hepatitis.’ In the immunocornpromised patient or transplant recipient, however, CMV infection may cause serious morbidity, including fever, arthralgias, enteritis, hepatitis, thrombocytopenia, leukopenia, encephalitis, interstitial pneumonia, and even delayed engraftment of bone marrow, and i t may be fatal.’-S Whereas the experimental antiviral agent, ganciclovir, has shown promise in treating serious CMV infection in some transplant settings, this therapy is toxic and has been of limited efficacy.h-lc’ I t may also be possible to attenuate serious CMV disease with prophylactic CMV hyperimmune globulin” or very large doses of immune serum globulin.’2 Still, prevention of CMV infection in transplant recipients is critical. In this review, we will briefly describe CMV infection, the role of the white cell (WBC) in disease transmission, and the types of infection that afflict transplant recipients. We will then examine the relative risks of various blood products and note the distinctions between patient groups that have recently become extremely important in determining triage policy for the use of the limited supply of CMV-seronegative products or their equivalent. Finally, we will attempt to define those patients who clearly require these specialized components and classify those for whom the use of blood products that do not transmit CMV infection is less critical or remains controversial. While CMV immunoglobulin and antiviral medications may change both the incidence and course of CMV infection, we will concentrate on disease prevention via seronegative blood products or their equivalent in seronegative recipients of seronegative solid organs and bone marrow.

Evaluation of the red cell storage lesion after irradiation in filtered packed red cell units

Packed red cell units (n = 10) were filtered and divided equally. One‐ half unit from each donor was irradiated (x) (3500 cGy). On Days 0, 14, 28, and 42, ATP, K+, Na+, lactate dehydrogenase (LDH), plasma‐free hemoglobin (PFH), and pH were determined. The reduction in ATP was greater in the irradiated than the nonirradiated (y) units by Day 42 (mean x−y: −70, p = 0.0005). The increase in K+ was greater in the irradiated than nonirradiated units on Days 14, 28, and 42 (mean x−y: 17−20, p = 0.0001). Decrease in pH and increases in LDH and PFH were significant (p less than 0.05) on Day 42 only. K+ increases added only 1.7 to 2.0 mmol per unit, a difference felt to be clinically insignificant. The changes noted in ATP, pH, LDH, and PFH are significant but minimal on Day 42 and imply that viability changes would also be minimal. These biochemical data support the storage of irradiated units for at least 28 days.

Autoimmune hemolytic anemia in Kawasaki disease: a case report

A 3‐year‐old boy presented with the fever, conjunctivitis, rash, and lymphadenopathy diagnostic of Kawasaki disease. Treatment with antibiotics, aspirin, and intravenous immunoglobulin was instituted. The hematocrit decreased from 35 percent on admission to 11 percent by hospital Day 10, and the white cell count had increased from 13.7 to 42 × 10(3) per microL, and the patient had a leukoerythroblastic blood smear. The direct antiglobulin test demonstrated IgG but not complement on the red cell (RBC) surface. An acid eluate reacted (titer of 4) with all panel cells in the antiglobulin phase. Intravenous immunoglobulin from the same lot used for treatment did not contain antibody that reacted with the patients group O RBCs or a panel of group O RBCs, but did contain IgG anti‐A and ‐B (titer of 4). The patient received a transfusion and was given methylprednisone. The direct antiglobulin test and acid eluate were negative 4 days later. The patient had an uneventful recovery. The distinction between antibody‐mediated hemolytic anemia and autoimmune hemolytic anemia is important in the treatment of this disease.

Development of a colorimetric dosimeter for quality control of blood units and irradiators

The development is reported of a reproducible colorimetric irradiation dosimeter that is easy to prepare as well as to interpret. Optimal chloroform, dithizone, and paraffin concentrations to produce a distinctive color change at > 1500 cGy (optimized for 3000 cGy) were determined by combining various concentrations of each component at 65 degrees C. The melted dosimetric material was poured into molds, allowed to solidify, and irradiated with doses ranging from 0 to 3000 cGy. Color change was evaluated visually and spectrophotometrically to determine reproducibility. Twenty‐percent chloroform (wt/wt) and a dithizone concentration of 5.0 × 10(‐5) M combined in paraffin (TP‐2) produced optimal color change from pink to green after > 1500 cGy. The change was reproducible, and 50 individuals were able to distinguish between irradiated and nonirradiated dosimeters. Additionally, five of five of these individuals correctly ranked five dosimeters in order of increasing irradiation from 0 to 3000 cGy, in increments of 750 cGy. This dosimeter is easy to make and easy to read and may allow blood banks to show unit‐by‐unit quality assurance for irradiated blood components and quality control of the irradiator itself.

Density gradient separation of peripheral blood stem cells: comparison of an automated cell processing device and manual methods

Peripheral blood stem cells were collected from normal donors by leukapheresis on a cell separator. The leukapheresis product contained 1.5 × 10(10) mononuclear cells (MNCs) and was divided into two aliquots that underwent either automated or manual density gradient separation with ficoll‐hypaque and subsequent washing. In the automated process, recovery of MNCs was 85 percent, reduction in platelet content was 64 percent, and the final hematocrit (Hct) was less than 1 percent. The manual separation resulted in 76‐percent MNC recovery, a 79‐percent reduction in platelet content, and a final Hct of less than 1 percent. The purified MNCs were then placed in methylcellulose culture at a concentration of 4 × 10(5) MNCs per mL. Quadruplicate 1‐mL aliquots were cultured, and colonies were counted and classified on Day 14. Comparison of automated and manual ficoll‐hypaque separations demonstrated no differences in the total, erythroid, or granulocyte‐ macrophage colony numbers. The cell processor used is fast, reliable, uncomplicated, and provides a sterile product containing progenitor cells that are not adversely affected by the automated ficoll‐hypaque separation.