Qualitative and quantitative changes of bone marrow cells in sensitized rabbits

Bone marrow of adult rabbits was dynamically investigated during the sensitization of animals with the complete Freund's adjuvant containing 10 per cent human gammaglobulins (five intramuscular injections of 1 ml adjuvant, one per week). Smears, imprints and paraffin sections from tibial and femoral bone marrow were examined in normal, unsensitized animals, and a week after the third, the fourth and the fifth antigenic stimulations. The differential count of about 10,000 elements of 20-25 smears and imprints allowed the establishment of normal and modified myelograms at each sacrificing term. A high increase in the number of monocytes, small lymphocytes and plasma cells was noticed after the third antigenic stimulation, with statistically significant values as compared to controls. The increase in the number of lymphocytes--including both T and B cells--was more marked after the 3rd antigenic stimulation, later on the proportional increase diminished, the proliferation maintaining itself "en plateau". The ratio between myeloblastic-myelocytic and erythroblastic-erythrocytic elements doubled after the third antigenic stimulation and increased up to six times after the fifth one, due to an absolute decrease of the erythroblastic-erythrocytic line.     

Relationships between cholesterol and phospholipid concentrations in the serum of humans, calves, rabbits and chickens

In humans, calves and rabbits very strong correlations were found between the concentrations of serum total cholesterol and phospholipids; in these species more than 70% of the variance in the level of serum phospholipids is accounted for by the variance in the serum cholesterol concentration. The regression coefficients in the equations relating the concentration of serum cholesterol to that of phospholipids were almost identical in humans and rabbits, but differed from those observed in calves and chickens. It is suggested that the rabbit is a suitable model animal for studying the relation between cholesterol and phospholipids in human serum.     

Ferritin in bone marrow and serum in iron deficiency and iron overload

Nonheme iron and ferritin in the bone marrow and serum ferritin was investigated in patients with iron deficiency anaemia or iron overload. As controls served patients without any disturbance of the iron metabolism. There is a precise correlation between the nonheme iron and ferritin in the bone marrow of patients with and without disturbance of iron metabolism. A correlation was also found between the ferritin in the bone marrow and the serum. Nonheme iron and ferritin in the bone marrow and serum ferritin was decreased in patients with iron deficiency anaemia. Conversely, the same parameters were increased in patients with iron overload.     

Migration of bone marrow progenitor cells in the adult brain of rats and rabbits

Neurogenesis takes place in the adult mammalian brain in three areas:Subgranular zone of the dentate gyrus(DG);subventricular zone of the lateral ventricle;olfactory bulb.Different molecular markers can be used to characterizethe cells involved in adult neurogenesis.It has been recently suggested that a population of bone marrow(BM)progenitor cells may migrate to the brain and differentiate into neuronal lineage.To explore this hypothesis,we injected recombinant SV40-derived vectors into the BM and followed the potential migration of the transduced cells.Long-term BM-directed gene transfer using recombinant SV40-derived vectors leads to expression of the genes delivered to the BM firstly in circulating cells,then after several months in mature neurons and microglial cells,and thus without central nervous system(CNS)lesion.Most of transgene-expressing cells expressed NeuN,a marker of mature neurons.Thus,BM-derived cells may function as progenitors of CNS cells in adult animals.The mechanism by which the cells from the BM come to be neurons remains to be determined.Although the observed gradual increase in transgene-expressing neurons over 16mo suggests that the pathway involved differentiation of BM-resident cells into neurons,cell fusion as the principal route cannot be totally ruled out.Additional studies using similar viral vectors showed that BM-derived progenitor cells migrating in the CNS express markers of neuronal precursors or immature neurons.Transgene-positive cells were found in the subgranular zone of the DG of the hippocampus 16 mo after intramarrow injection of the vector.In addition to cells expressing markers of mature neurons,transgene-positive cells were also positive for nestin and doublecortin,molecules expressed by developing neuronal cells.These cells were actively proliferating,as shown by short term BrdU incorporation studies.Inducing seizures by using kainic acid increased the number of BM progenitor cells transduced by SV40vectors migrating to the hippocampus,and these cells were seen at earlier time points in the DG.We show that the cell membrane chemokine receptor,CCR5,and its ligands,enhance CNS inflammation and seizure activity in a model of neuronal excitotoxicity.SV40-based gene delivery of RNAi targeting CCR5 to the BM results in downregulating CCR5 in circulating cells,suggesting that CCR5 plays an important role in regulating traffic of BM-derived cells into the CNS,both in the basal state and in response to injury.Furthermore,reduction in CCR5 expression incirculating cells provides profound neuroprotection from excitotoxic neuronal injury,reduces neuroinflammation,and increases neuronal regeneration following this type of insult.These results suggest that BM-derived,transgeneexpressing,cells can migrate to the brain and that they become neurons,at least in part,by differentiating into neuron precursors and subsequently developing into mature neurons.     

Testosterone and estradiol concentrations in serum, velvet skin, and growing antler bone of male white-tailed deer

The growth and mineralization of antlers correlate with the seasonal variation of serum androgens. Whereas seasonal levels of testosterone (T) in plasma are well established, steroid concentrations have not yet been determined in the tissues of growing antlers. Therefore, RIA was used to determine T and 17beta estradiol (E2) in serum, and three areas (tip, middle, and base) of the antler bone and the antler skin, called velvet. Blood and antler tissues of white-tailed deer (Odocoileus virginianus) were collected from May to August. The difference between levels of T and E2 among the sites was calculated using the square root transformation followed by a mixed model analysis with individual deer and an interaction of individual and year (individual(*)year) as a random factor. Concentrations of T in serum (799+/-82 pg/ml) were higher than T values in the velvet (589+/-58 pg/ml, P<0.01) and in the antler bone (538+/-58 pg/ml, P<0.001). Estradiol concentrations differed among antler tissues and serum (P<0.001) and between years (P<0.01). Estradiol concentrations in serum (25+/-25 pg/ml) were consistently lower than those in antler bone (208+/-11 pg/ml, P<0.001) and velvet (150+/-12 pg/ml, P<0.001). The E2:T ratio in serum was 1:10-60. The same ratio for the antler bone was only 1:2-3 and for the velvet 1:3.5. It is concluded that higher T and lower E2 concentrations found in plasma, as compared to antler bone or antler velvet, may indicate a partial metabolism of systemic androgens into estrogens xin the tissues of growing antlers.     

Chemical composition of bone marrow after exposure of rabbits to nitrogen mustard

Rabbits were injected with 2.5 mg./kg. of methylbis(2-chloroethyl)-amine hydrochloride while the marrow of the right leg was protected by clamping the blood vessels which supply it. There was a marked lowering of the lipide-free solid content of the affected marrow. The lipide concentration was increased, but the change was not of the order of magnitude one would expect from the morphological appearance.     

Cryopreservation of marrow, purging and autologous bone marrow transplantation in childhood

Since 1984 bone marrow from 42 children with acute lymphoblastic leukaemia, non Hodgkin's lymphoma and neuroblastoma was cryopreserved. In 5 cases (c-ALL, NHL and B type) the marrow was purged by using a cocktail of three monoclonal antibodies (VIL A1, VIB C5, VIB-E3). Up to now 13 children (ALL/10, neuroblastoma/3) were autografted (one of them after purging) after supralethal chemoradiotherapy. Except one child with early death all patients had engraftment: a level of 1.0.10(9)/l leukocytes was reached at days 10-33 (median, 19); platelet level over 60.10(9)/l at days 32-60 (median, 41). 2 children died on treatment related complications, one on infection after full haematological restitution, 2 patients alive with relapse, 8/13 alive in CCR and well.     

Exposure to ambient particles accelerates monocyte release from bone marrow in atherosclerotic rabbits

Exposure to air pollution [particulate matter, particles <10 microm (PM(10))] causes a systemic inflammatory response that includes stimulation of the bone marrow (BM) and progression of atherosclerosis. Monocytes are known to play a key role in atherogenesis by migration into subendothelial lesions where they appear as foam cells. The present study was designed to quantify the BM monocyte response in Watanabe heritable hyperlipidemic (WHHL) rabbits after PM(10) exposure. WHHL rabbits were given twice weekly intrapharyngeal instillations of 5 mg of PM(10) for 4 wk to a total of 40 mg and compared with control WHHL or New Zealand White (NZW) rabbits. The thymidine analog 5'-bromo-2'-deoxyuridine was used to label dividing cells in the BM and a monoclonal antibody to identify monocytes in peripheral blood. The transit time of monocytes through the BM was faster in WHHL than in NZW rabbits (30.4 +/- 1.9 h vs. 35.2 +/- 0.9 h, WHHL vs. NZW; P < 0.05). PM(10) instillation exposure increased circulating band cell counts, caused rapid release of monocytes from the BM, and further shortened their transit time through the BM to 23.2 +/- 1.6 h (P < 0.05). The percentage of alveolar macrophages containing particles in the lung correlated with the BM transit time of monocytes (r(2) = 0.45, P <0.05). We conclude that atherosclerosis increases the release of monocytes from the BM, and PM(10) exposure accelerates this process in relation to the amount of particles phagocytosed by alveolar macrophages.