[The ratio of various lymphocyte populations in bacillary dysentery and nonspecific ulcerative colitis]. / Sootnoshenie razlichnykh populiatsii limfotsitov pri bakterial'noi dizenterii i nespetsificheskom iazvennom kolite.

The comparative study of the content of different lymphocyte populations of the peripheral blood in pathological states accompanied by lesions of the mucous membrane of the large intestine has been made. In shigellosis patients the accumulation of lymphocytes having the signs of young post-thymic forms (theophylline-dependent populations) and functionally active forms (Ea-rosette-forming cells) occurs in the circulating blood. In unspecific ulcerous colitis only an increase in the number of immature lymphocytes (theophylline-dependent lymphocytes and autorosette-forming cells) is observed. In both pathological states an increase in the number of O-lymphocytes with Fc gamma-receptors occurs in the circulation blood.

Cellular and molecular studies on infant null acute lymphoblastic leukemia.

We have studied the cellular and molecular basis of eight cases of infant null acute lymphoblastic leukemia (ALL). All eight patients were under 9 months of age and presented with leukocyte counts in excess of 60 X 10(9)/L, organomegaly, and in two cases CNS infiltration. Although seven cases were morphologically classified as ALL, one patient had both lymphoid and myeloid features. Phenotypic analysis of leukemic blasts from all patients showed a typical null ALL pattern, ie, CD10 (common ALL antigen)-negative, strongly HLA-DR-positive, and CD19 (B4)-positive. The presence of terminal deoxynucleotidyl transferase (TdT) at presentation was positive in six patients' cells and negative in two. Two patients also expressed the myeloid-associated markers CD33 (MY9) and CD15 (TG1), and coexpression of CD19 and CD33 was confirmed in these two by using dual marker flow cytometry (fluorescence-activated cell sorting). Electron microscopic examination of the same two patients' cells showed the presence of monocytoid blasts that labeled with the pan-B cell antibody B4 (CD19). Short-term culture of one of these patients cells in the presence of phorbol ester resulted in the majority of the cells exhibiting myeloid markers, strong nonspecific esterase positivity, and phagocytic properties. Cytogenetic analysis showed the common feature in 7 of 8 cases to be a break in band 11q23. Molecular analysis of DNA from the blast cells of all eight patients showed rearrangement of the immunoglobulin heavy-chain genes in all cases without, however, any evidence of kappa light-chain rearrangement. T cell receptor genes were present in the germline configuration in all cases. Rearrangements of the c-ets 1 oncogene, which maps to band 11q23, were not detected, thus providing no evidence for involvement of this oncogene in the common disease process. Our data indicate that although infant null ALL may present as a heterogeneous disease the similarity of many features between cases suggests a common derivation from a precursor cell sharing phenotypic and genotypic features of both B and myeloid progenitor cells.

Cellular subsets involved in cell-mediated immunity to murine Plasmodium yoelii 17X malaria.

Cell mediated immunity to nonlethal Plasmodium yoelli 17X (PY17X-NL) was examined in the CBA/CaJ mouse by adoptive transfer of sensitized T lymphocyte subsets. In intact mice, PY17X-NL causes a self-limiting infection with parasitemia levels ranging from 10 to 25% of total red blood cells. Upon recovery, mice are refractory to subsequent challenge with the homologous parasite. In T cell-depleted mice, PY17X-NL infections are extremely virulent and result in death of the host after parasitemia levels reach 50% or higher. The transfer of either Lyt-1 T cells or Lyt-2 T cells from immune animals into normal, naive animals produced accelerated recovery to subsequent infection. However, this adoptive transfer of immunity by either subset was dependent upon the presence of an I-J+, Lyt-null cell in the immune population. T cell deprivation precluded the ability of animals to control blood-stage infections. When T cell-depleted mice were reconstituted with naive, Ig-negative (T cell-enriched) spleen cells, parasitemia levels were controlled and the parasites were eliminated. When T cell-deprived animals were reconstituted with naive Lyt-1+2-, Ig-negative spleen cells, they experienced twofold higher parasitemias of longer duration than mice receiving unfractionated cells. Two of six of these Lyt-1 mice died of fulminant infections, suggesting that the presence of naive Lyt-2 cells enhances the degree of protection. Immune Lyt-2 T cells were highly protective in T cell-depleted animals. Protection by sensitized Lyt-1 T cells correlated with the induction of a monocytosis. On the other hand, protection by Lyt-2T cells occurred in the absence of monocytosis. The possibility that the immunity induced by each T cell subset is mediated by a different effector mechanism is discussed.

Identification of erythroid colony progenitors in a subset of human peripheral null lymphocytes devoid of Fc receptors.

This study was aimed at purifying the progenitors of erythroid burst units (BFU-E) from human peripheral blood. Human mononuclear leukocytes from five normal donors were fractionated into several mononuclear cell subpopulations, including null lymphocytes with (null Fc+) and without (null Fc-) receptor for the Fc fragment of immunoglobulin G, through a succession of rosetting procedures and discontinuous Ficoll-Hypaque gradient centrifugations. The fractionated cells were separately cultured for 14 days in plasma clots in the presence of erythropoietin. Among fractionated cell subpopulations large and numerous BFU-E derived colonies grew only from the Fc- null lymphocyte subpopulation. This fraction, representing less than 4% of all mononuclear cells, also contains cells (42 + 11%) capable to differentiation towards the B-cell and plasma-cell lineages. The Fc+ null lymphocytes, representing less than 9% of all mononuclear cells, contained 15.2 + 3.3% cells capable of differentiation toward the T-cell lineage. The whole null lymphocyte subpopulation generated half the number of BFU-E colonies expected from its content in Fc- null lymphocytes. These data demonstrate that the progenitor of erythroid cells (BFU-E) resides in a small heterogeneous null Fc- subpopulation of circulating lymphocytes and suggest that its in vitro differentiation, though generally subjected to inhibitory and enhancing influences from other circulating cell subpopulations, does not necessarily require interaction with other peripheral blood cells.