Exhaustion of mature marrow neutrophils in neonates with sepsis.
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Publications and source records attributed to G Rothstein.
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The availibility of neutrophils is an important factor in host resistance to bacterial infection. Therefore, circulating and storage neutrophil quantification was carried out on groups of neonatal rats intranasally inoculated with type II group B streptococci. The dose of type II group B streptococci used produced 56% mortality in 48 neonatal rats with death being due to pneumonia and sepsis. Neutropenia (1300 +/- 150/mm3 versus 2300 +/- 170/mm3; mean +/- S.D.; P < 0.01) and an elevation in band/polymorphonuclear ratio (0.98 +/- 0.04 versus 0.30 +/- 0.04; P < 0.01) were observed in infected neonatal rats 24 hr following inoculation. Femoral marrow as well as splenic and hepatic neutrophil storage compartment quantification revealed dimunition of postmitotic (polymorphonuclear, band, and metamyelocyte) neutrophils in the infected group (P < 0.01) with sparing of the proliferative neutrophils (myeloblasts, promyelocytes, and myelocytes). Repletion of the myeloid but not the splenic or hepatic neutrophil storage compartments with normalization of the neutrophil count and band/polymorphonuclear ratio occurred in animals surviving 72 hr. These studies establish that neutropenia and neutrophil storage pool depletion are prominent features of experimental type II group B streptococci infection in neonates.
To assess release of neutrophils from the neutrophil storage pool (NSP) and subsequent neutrophil migration into tissue sites, polyvinyl sponge discs were placed into subcutaneous pockets in either newborn or 4-wk-old rats. After 20 hr, the sponges were removed, and the animals' NSP size and the number of neutrophils which had migrated into the sponges were measured. In response to the sponge stimulus, neonatal rats released 83.6 +/- 1.2% (mean +/- S.E.) of their NSP (106.3 +/- 15.3 X 10(5) neutrophils), whereas the older animals released 28.4 +/- 5.0% (628.5 +/- 124.4 X 10(5) neutrophils) of their NSP (P less than 0.001). Neonatal neutrophils displayed a decreased ability to successfully migrate from the NSP to the sponges. The proportion of released neutrophils accumulating in the sponges was 9.2 +/- 0.6% in the neonates, compared with 58.5 +/- 7,8% (P less than 0.001) in the 4-wk-old rats.
Hematologic toxicity occurred when trimethoprim-sulfamethoxazole was given for prolonged periods to renal allograft subjects also treated with azathioprine. In six such patients, the incidences and duration of neutropenia and thrombocytopenia were greater than in 25 similar allograft recipients treated with azathioprine alone. In bone marrow culture, the antifolate action of trimethoprim-sulfamethoxazole enhanced the marrow-suppressive effect of 6-mercaptopurine, the active moiety cleaved from azathioprine. These studies show that in renal allograft recipients treated with azathioprine, the prolonged use of trimethoprim-sulfamethoxazole may result in life-threatening hematotoxicity.
The mechanisms responsible for the unusual susceptibility of multiple myeloma (MM) patients to infections are incompletely defined. Since MM is associated with decreased production of normal serum proteins, we investigated the possibility that the production of opsonins might also be impaired. The neutrophil chemiluminescence assay of opsonization was used to evaluate the ability of serum from patients with MM to opsonize zymosan. It was found that sera from 18 MM patients exerted only 50% +/- 2.5% (mean +/- SEM) of the opsonic activity found in 18 control sera (p less than 0.001). In mixture experiments, untreated normal serum completely restored the opsonic activity of MM serum, suggesting a deficiency of opsonic factors rather than an inhibitor. In other mixture experiments, heat-inactivated normal serum only partially corrected the opsonic defect in MM serum. Serum from three patients had low C3 levels, and treatment of particles with these resulted in a greater opsonic defect than the patient population as a whole (p less than 0.02). No correlation between the opsonic defect and infections was established over an 18-mo period. These data suggest that MM serum lacks both heat-stable and heat-labile opsonic activity, the direct clinical significance of which remains to be clarified. However, these studies support the concept that defective host resistance in MM may be multifactoral, combining opsonic abnormalities with other defects previously described.
Some pitfalls in the interpretation of neonatal leukocyte counts are identified. The well-known variability in neonatal leukocyte counts was investigated by simultaneously sampling arterial, venous and capillary blood, and during periods of rest and mild and violent exercise. Venous blood leukocyte counts were 82% +/- 3.5 (mean +/- SE, P = less than .001) of counts in simultaneously drawn capillary blood from heel punctures; arterial blood counts were 77% +/- 5.3 (P less than .001) of capillary blood values. Following violent crying, capillary blood leukocyte counts increased to 146% +/- 6.1 (P less than .001) of baseline values, and a shift to the left occurred. Milder exercise induced an increase to 113% +/- 5.2 (P less than .05), without a leftward shift. Thus, counts from different vascular sources cannot be considered equivalent. Also, counts from vigorously crying babies may show leukocytosis and a leftward shift, and erroneously suggest bacterial infection. It is recommended that serial counts be obtained from a consistent vascular source in resting babies.
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We measured the effect of lithium on the blood neutrophil mass and neutrophil production, using standard di-isopropylfluorophosphate (DF32P) methods. In 12 lithium-treated patients the total blood neutrophil pool was 105 (42 to 270) x 10(7) cells per kilogram (median and 95 per cent limits) as compared with 61 (27 to 138 x 10(7) in 71 controls (P less than 0.001). The neutrophil turnover rate, a measure of effective neutrophil production, was 230 (108 to 380) x 10(7) cells per kilogram per day in the lithium-treated group and 160 (62 to 400) x 10(7) in the controls (P less than 0.05). Neutrophil migration into skin lesions ranged from 34 to 469 x 10(5) cells per day in the lithium-treated patients, as compared with 1.7 to 68 x 10(5) in 10 controls. Lithium causes enlargement of the total circulating neutrophil mass and accelerates neutrophil production without impairing neutrophil migration into skin lesions.
The process by which resting hemopoietic stem cells become activated is poorly understood, but it has been suggested that cyclic nucleotide levels in the cell may play an important role. In the present study, the effect of various, nucleotides and stimulators of nucleotide synthesis upon the formation of in vitro granulocyte colonies has been examined. It was found that physiologic concentrations of 3', 5'-cyclic guanosine monophosphate enhanced the formation of granulocyte-macrophage colonies in the presence of colony-stimulating activity. The cells sensitive to cGMP activation were resistant to thymidine suicide and could not be activated by colony-stimulating activity alone. Therefore it was suggested that the cGMP sensitive stem cell was an ordinarily resting stem cell which was triggered into a proliferative state by cGMP.
Since lithium causes granulocytosis in some patients, its effect upon granulocyte production was investigated using mouse marrow in the agar culture system. When lithium was added to semisolid cultures of mouse marrow, there was no stimulation of colony formation in the absence of colony-stimulating activity (CSA). In addition, lithium did not potentiate the action of already formed CSA. However, lithium did stimulate the production of CSA by lung tissue. Lithium enhancement of CSA production was blocked by puromycin, indicating that lithium action required active new protein synthesis. It was concluded that lithium promoted enhanced granulocyte production in vitro by stimulating the synthesis of CSA.
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The kinetics of blood neutrophils was investigated by means of the in vitro radioactive diisopropyl fluorophosphate method in 35 patients with a chronic, steady-state neutropenia. There were 17 patients in whom the half disappearance time of neutrophils was normal. In 10 of these patients, the production of neutrophils was low and in 7, production was normal. In 18 patients the half disappearance time of neutrophilic granulocytes was shorter than normal. The production of neutrophilic granulocytes was low in five of these patients, normal in eight patients, and increased in five. An attempt was made to correlate other laboratory measurements with the kinetic picture, but no relationship was found; the marrow neutrophil reserve as measured by endotoxin or cortisol injection; marrow cellularity on aspiration or biopsy; in vitro-labeling index with (3)HTdR; or serum lysozyme concentration proved of no value in identifying the various kinetic groups. The only finding that seemed to correlate with the kinetic picture was the presence or absence of splenomegaly. In 12 of the 18 patients with a short half disappearance time, splenomegaly was present whereas in 15 of 17 patients with a normal half disappearance time, there was no splenomegaly. Of 20 patients with greater than 1000 neutrophils per mm(3), 17 were found to have a normal total-blood neutrophil pool. Thus these patients, with many of their cells marginated, agree to have a "shift neutropenia."Myelocyte to blood transit time and myelocyte generation time, as measured in seven patients by in vivo labeling with diisopropy fluorophosphate, proved to be essentially normal. Thus, it appears that in chronic neutropenia, increased or decreased production of neutrophils is accomplished by increasing or decreasing early precursor input into the system.
A millipore diffusion chamber system was used to cultivate mouse marrow in the abdomens of irradiated and unirradiated host mice for 24 hr. When the irradiated hosts were 72, 96, or 120 hr postirradiation, the number of blasts and promyelocytes in the implanted chambers after cultivation was greater than those in the same marrow cultivated in unirradiated hosts. These data indicate that in vivo, there is stimulation of granulocytopoiesis by a diffusible factor or factors.
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