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PubMed1976

Peripheral lymphocyte subpopulations in human falciparum malaria.

The concentration of circulating T, B, and 'null' lymphocytes was determined in thirty children and three adults with Plasmodium falciparum infections in West Africa. During infection, both percentage as well as concentration of T cells were decreased as compared to levels following treatment. The percentage but not concentration of B cells was increased. Both percentage and concentration of 'null' cells were increased in malaria. Patients with splenomegaly had the most severe alterations in T-cell number; no other historic or clinical parameter correlated with the degree or pattern or change in circulating lymphocyte subpopulations. These alterations were rapidly reversible after antimalarial treatment and presumably represent the sequestration of T cells in the spleen or other organs.

Adult↗
PubMed1979

Immune status in Crohn's disease. 3. Peripheral blood B lymphocytes, enumerated by means of F(ab)2-antibody fragments, Null and T lymphocytes.

In the peripheral blood of patients with Crohn's disease (CD) the numerical distribution of the three major B lymphocyte subsets was determined by the identification of surface immunoglobulins using F(ab)(2)-antibody fragments. T cell counts were also obtained and the number of null cells was calculated. Twenty-eight patients with Crohn's disease including 14 patients with previously untreated and very short-standing disease (group CD 1) and 14 patients with long-standing and/or previous drug treated disease (group CD 2) were compared with 28 sex and age-matched normals as well as with 13 patients with acute inflammatory bowel disease (group D). Patients in group D and inactive patients of group CD 1 showed a significant absolute lymphocytosis due to an increase in both the three B cell subsets and the T cells, without changes in the null cells. While the proportion of T cells was normal, there was a significant relative B lymphocytosis and a relative null cytopenia in these patients. Active CD 1 patients, however, showed significantly lower absolute lymphocyte and T cell numbers. In group CD 2, there was a significant absolute lymphopenia caused by an equal decrease in B and T cells. Highly active CD 2 patients showed higher absolute null cell counts than inactive patients. With increasing disease duration there was a significant decrease of the relative and absolute B cell concentrations. The data obtained suggest that T and B cell populations in the peripheral blood are reduced in certain patients with Crohn's disease and that this occurs secondarily to activity of disease, chronicity of disease, and the effects of therapy.

Adolescent↗
PubMed1979

Antibody-dependent cell-mediated antibacterial activity of human mononuclear cells. I. K lymphocytes and monocytes are effective against meningococi in cooperation with human imune sera.

In cooperation with human heat-inactivated antisera from adults immunized with group C meningococcal polysaccharide, normal human peripheral blood mononuclear cells significantly decreased the viability of group C meningococci (Mgc) in vitro. K lymphocytes (Null cells) and monocytes, (but not T or B lymphocytes) were capable of effecting antibody-dependent cell-mediated (ADC) antibacterial activity in this system. The degree to which meningococcal viability was decreased was a function of the length of the test incubation, the concentration of effector cells, and the amount of antiserum used in the assay. When specific antibodies directed against Mgc were adsorbed from the antiserum, cell-mediated antibacterial activity was abolished. ADC antibacterial activity was also abrogated by performing the assay at 4 degrees C or by heating effector cells to 46 degrees C for 15 min before the assay, Similarities between the ADC antibacterial system and previously described ADCC assays are discussed. The data suggest the K cells (as well as monocytes) may play a role in host immune defense against pathogenic bacteria.

Antibodies, Bacterial↗
PubMed1978

Technical improvements in the mixed antiglobulin rosetting reaction with consequent demonstration of high numbers of immunoglobulin-bearing lymphocytes in viable preparations of human peripheral blood.

A modification of the mixed antiglobulin rosetting reaction (MARR) to improve sensitivity as a test for immunoglobulin (Ig)-bearing human blood lymphocytes is described. A mean 5.7%, lymphocytes Ig-positive by the MARR when rosettes were formed in medium containing 0.2% bovine serum albumin (BSA), increased to 20% when rosettes were formed in 5% BSA or by incubating the lymphocytes or indicator erythocytes with Vibrio cholerae neuraminidase before rosetting. Under these various rosetting conditions the MARR is as sensitive as the direct antiglobulin rosetting reaction (DARR). Further, with the MARR, false positive rosette formation due to unusual antimembrane antibodies can be excluded during the mixed antiglobulin rosetting procedure by use of blocking controls. Substitution of F(ab)2 antiglobulin for IgG anti-gamma, anti-alpha and anti-mu did not reduce the number of lymphocytes demonstrable with the MARR, indicating that the MARR does not react with adsorbed Ig molecules on lymphocytes. Summation of the number of sheep erythrocyte (E) rosetting lymphocytes and mixed antiglobulin rosetting lymphocytes approximated 100%, yet in T-enriched preparations a maximum of 4% of lymphocytes were Ig-positive by the MARR, suggesting that null lymphocytes which have been reported to be E-negative and immunofluorescence-negative are B lymphocytes with surface Ig determinants.

Animals↗
PubMed1983

"Helper" and "suppressor" T lymphocytes regulating blood cell formation in man.

Human hemopoietic progenitor cells have been characterized as null lymphocytes. These primitive precursors are subject to interaction with mature cells which are derived from the thymus. Such T lymphocytes exist in several subpopulations which can exhibit "helper" and "suppressor" activity in various immune responses. Evidence for the involvement of these cells in hematopathological disorders has been presented and the possibility of a physiological role for helper and suppressor T cells in hemopoiesis has been discussed. It is proposed that "steady state" blood cell formation is maintained, at least in part, by the preponderance of suppressors in the bone marrow, while the dominant helper population in peripheral blood can recirculate under the influence of corticosteroids with consequent stimulation of hemopoiesis. The influence of histocompatibility antigens on this process of cellular regulation remains to be determined.

Hematologic Diseases↗
PubMed1979

T and B lymphocytes in the ontogenetic development of man.

Cord blood lymphocytes of premature and mature fetuses and peripheral blood of infants and adults were studied by rosette techniques and membrane immunofluorescence. Percentage of lymphocytes carrying surface immunoglobulins, receptors for complement and receptors for uncoated sheep erythrocytes or receptors for Fc IgG was determined. T lymphocyte receptors were found to appear later in ontogeny than the receptors typical of B lymphocytes. Receptors for Fc IgG were the earliest to appear: already in premature fetuses the percentage of lymphocytes resembled the one seen in healthy adults. However, the absolute number of T cells increased during development of fetuses and infants and slightly decreased in adults. On the other hand, the absolute number of B lymphocytes were highest in mature fetuses and decreased in subsequent age groups. In the course of human ontogeny a progressive increase was found in lymphocytes carrying full sets of T or B lymphocyte receptors, paralleled by a corresponding decrease in mean values of "null" lymphocytes free of detectable receptors.

Adolescent↗
PubMed1982

Serological analysis of cell surface antigens of null cell acute lymphocytic leukemia by mouse monoclonal antibodies.

Nine antigens systems were defined. Two were related to HLA-A,B,C and to Ia-like antigens; the others could be grouped into three categories. (i) NL-22, NL-1: NL-22 antibody reacted with leukemia cells from 12 to 16 cases of null cell acute lymphocytic leukemia (null-ALL) but not with any other type of leukemia tested or with lymphoid cells of various origins. Among cultured cell lines tested, one (NALM-6) of three null-ALL cell lines was positive, the others were negative. Absorption analysis confirmed the restriction of NL-22 antigen to null-ALL. NL-1 antibody was reactive with leukemia cells from 10 to 16 cases of null-ALL and 3 of 6 cases of chronic myelocytic leukemia in blastic crisis (CML-BC). The antigen was present also on a minor population of normal lymphoid cells. The distribution and molecular weight (100,000; glycoprotein) of the NL-1 antigen resembled that of the previously described common ALL antigen (cALL). (ii) NL-30, NL-4: Both antibodies exhibited almost identical patterns of reactivities against cultured cell lines tested. They reacted with leukemia cells from some cases of null-ALL, adult T-cell leukemia, and CML-BC, although they showed discordance in their reactivities against a panel of leukemia cells, (iii) NL-9, NL-8, NL-25: These three antibodies detect serologically distinguishable determinants on a broad range of leukemias and normal lymphoid and hematopoietic cell types. The antibodies analyzed in this study provide evidence for the heterogeneity of null-ALL by demonstrating a variety of antigen phenotypes on leukemia cells. One of the antigens (NL-22) appears to be restricted to null-ALL.

Animals↗
PubMed1976

Lysosomal acid hydrolases in human lymphocyte subpopulations.

Acid phosphatase and beta-glucuronidase activities have been determined cytochemically in T, B and null lymphocytes as part of an effort to charaterize the human haemopoietic stem cell. A combination of weak acid phosphatase activity and strong beta glucuronidase staining, in the form of a single large granule, has been shown to be specific for T cells. On the basis of this approach alone, non-T cells could not be further subclassified. Further cytochemical evaluation is being explored.

Acid Phosphatase↗
PubMed1987

Surface receptors and immune activity of purified human circulating mononuclear cells. III. The mechanisms of lysis, by lymphocytes and monocytes, of target cells in the lymphocyte-dependent and monocyte-dependent ADCC, NK, NOCC, and MICC cytotoxic reactions.

The abilities of unfractionated mononuclear cells (MNC), monocytes (98-99% pure), and lymphocytes (98-99% pure) to carry out the lysis of target cells in the ADCC, NK, NOCC, and MICC assays were compared. Lymphocytes by themselves were able to lyse the CRBC (ADCC), K-562 (NK), and RRBC (MICC) target cells. The monocytes were very effective in the lysis of the CRBC (MICC) target cells. However, the lysis of two other target cells--RRBC (NOCC) and HRBC (ADCC)--required the simultaneous presence of both lymphocytes and monocytes in order to effect optimal lysis. Soluble factor(s) secreted by the cytotoxic cells capable of lysing the target cells were detected only in the NK assay. The activity of the soluble cytotoxic factor (NKCF) was only 25-40% of that exhibited by the cytotoxic NK cells and it was secreted by the cytotoxic cells after 48 hr of culture and not 24 hr of culture which is the usual assay condition. The NKCF was cytotoxic only to the NK target cells and not to the target cells used in the ADCC, NOCC, and MICC cytotoxic assays. Different classes of lymphocytes were cytotoxic in the monocyte-independent assays [ADCC (CRBC), NK (K-562), and MICC (RRBC)]. The null lymphocytes and the T lymphocytes were the primary cytotoxic cells in the ADCC and MICC assays, respectively, whereas the T, B, and null cells were almost equally cytotoxic in the NK assay. With respect to the monocyte-dependent assays [ADCC (HRBC), NOCC (RRBC), and MICC (CRBC)], the cytotoxic activity of any one class of lymphocytes failed to approach that of the unfractionated MNC. The T cells were the most cytotoxic; the B cells exhibited limited cytotoxic activity in only the ADCC assay and the null cells showed no cytotoxic activity. However, the combination of T and non-T cells and, to a lesser extent, T and B cells, exhibited much greater cytotoxic activity than the individual cells and together were as cytotoxic as the unfractionated MNC. It is concluded that, depending upon the selection of the target cells, lysis in the ADCC, NK, NOCC, and MICC assays may be effected by lymphocytes only, by monocytes only, by both monocytes and lymphocytes, or as a result of lymphocyte-monocyte collaboration. In the latter instance more than one class of lymphocytes must be present in order for maximum cytotoxic activity to be expressed.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1986

Canine cyclic hematopoiesis: alterations in T lymphocyte subpopulations in peripheral blood, lymph nodes, and thymus of gray collie dogs.

Cyclic hematopoiesis (CH), also called cyclic neutropenia, is an inherited disorder known to occur in both humans and gray collie dogs. Previous reports have provided ample evidence to suggest that lymphocyte activity and regulatory mechanisms may be abnormal in CH. The present study examined the lymphocyte populations of several lymphoid compartments of gray collie dogs. The percentage of B lymphocytes in the lymph nodes of CH dogs was significantly increased whereas that of null lymphocytes was decreased. The percentage of T lymphocytes did not differ between CH and normal dogs, however, the proportions of T lymphocyte subpopulations were significantly different. The levels of T lymphocytes expressing IgGFc receptors (T gamma) in the thymus, lymph nodes, and peripheral blood were significantly increased; whereas the levels of T lymphocytes expressing IgMFc receptors (T mu) were significantly decreased. The percentage and absolute numbers of T gamma and T mu lymphocytes cycled in CH dogs. The percentage and absolute numbers of neutrophils were greatest when that of T gamma lymphocytes was reduced. The cycles of monocytes and T gamma lymphocytes occurred in close association and a linear relationship between the levels of these cells was observed both in terms of percentage (r = 0.62; P less than 0.01) and absolute number (r = 0.67; P less than 0.05). The percentage of T gamma and T mu lymphocytes were inversely correlated (r = -0.68; P less than 0.01).

Agranulocytosis↗
PubMed1983

The phytohaemagglutinin response and lymphocyte subpopulations in young Blacks and Indians with insulin-dependent diabetes mellitus.

The lymphocyte transformation response to phytohaemagglutinin (PHA) and the relative numbers of T, B and null lymphocytes were studied in 32 insulin-dependent diabetics and 32 healthy matched controls. The mean stimulation index (Sl) of the 18 patients with poorly controlled diabetes mellitus was significantly lower than that of controls. No difference was seen in the mean Sl values of well-controlled diabetics compared with controls. Neither the well-controlled group nor the poorly controlled group showed any significant differences in the mean counts of the various lymphocyte subpopulations when compared with controls.

Adolescent↗
PubMed1983

Isolation of murine small bowel intraepithelial lymphocytes.

A method for the preparation of cellular suspensions of the epithelium of murine small bowel for the purpose of isolation and recovery of intraepithelial lymphocytes employing intraluminal hyaluronidase digestion is described. Discontinuous Percoll centrifugation of these suspensions yielded a 76-82% pure population of intraepithelial lymphocytes. Between 1.6 and 4.0 X 10(7) viable intraepithelial lymphocytes were obtained per gram of gut. The isolate contained approximately equal numbers of T, B and null lymphocytes.

Animals↗
PubMed1988

Flow cytofluorimetric analysis of lymphocyte subset alterations in cattle infected with bovine viral diarrhea virus.

Clinically normal, bovine viral diarrhea virus (BVDV)-seronegative, 7 to 9-month-old steers were inoculated intranasally with NY-1, a noncytopathic strain of BVDV, or exposed intramuscularly to killed BVDV. Indirect immunofluorescence staining with monoclonal antibodies specific for bovine leukocyte subsets followed by flow cytometric analysis was used to monitor subsequent hematologic alterations. Infection with BVDV resulted in a transient leukopenia which was characterized by decreases in the absolute numbers of circulating T lymphocytes, including BoT4+ ("helper") and BoT8+ ("cytotoxic/suppressor") subsets, B lymphocytes, and neutrophils. There was no significant variation in numbers of non-T, non-B ("null") lymphocytes or monocytes. Exposure to inactivated BVDV in a combination vaccine did not cause significant alteration in the circulating numbers of any major leukocyte subset; however, significant variation was seen in the BoT4/BoT8 ratios and in the numbers of cells expressing major histocompatibility complex (MHC) class II antigens.

Animals↗
PubMed1984

Characterization of a novel HTLV-infected cell line.

A man from Chile developed an aggressive mature T cell leukemia associated with marked eosinophilia. The neoplastic lymphocytes were of T helper surface phenotype, and they expressed the p24 and p19 antigens of human T cell leukemia virus (HTLV). A cell line (ME) was established from the patient's peripheral blood cells that was initially composed of eosinophils and T and B lymphocytes. The B lymphocytes of the cell line are polyclonal and contain Epstein-Barr virus (EBV) DNA. Many of the T lymphocytes, a few of the B lymphocytes, and none of the eosinophils express HTLV p19 and p24 antigens. By 6 months of culture, the ME line no longer contained eosinophils. A variant line of ME was established; this variant (ME-2) is notable because the cells (greater than 80%) adhere tightly to the bottom of the culture flask; they do not express T lymphocyte markers, but 30% of the cells contain cytoplasmic mu heavy immunoglobulin chains. These pre-B and null lymphocytes contain p19 and p24 antigens (80% of cells), have the HTLV-I genome, and are able to transform normal T lymphocytes in vitro. We isolated a B lymphocyte clone (11A) from ME that expresses cytoplasmic immunoglobulin (70% of cells) and p19 and p24 antigens (75% of cells), contains the EBV and HTLV genomes, and can transform T lymphocytes from normal volunteers. These data show that B lymphocytes can be infected with HTLV, although no disease of HTLV-infected B lymphocytes has been reported. The T lymphocytes from normal adult peripheral blood were easily immortalized (about 70% efficiency) by cocultivation with lethally irradiated ME cells. Twenty-five of 27 of the transformant lines were composed of T lymphocytes with helper antigens, and two of the lines were of T suppressor antigen phenotype. All the cell lines that were tested constitutively produce lymphokines, including colony-stimulating factor (CSF), erythroid-potentiating activity (EPA), macrophage migration-inhibitory factory (MIF), neutrophil-inhibitory factor (NIF), and differentiation-inducing factor (DIF).

Adult↗
PubMed1983

Survival and PHA-stimulation of gamma-irradiated human peripheral blood T lymphocyte subpopulations.

Human peripheral blood T lymphocyte subpopulations were identified and isolated on the basis of their ability to bind IgG (T-G), IgM (T-M), or neither immunoglobulin class (T-null). Lymphocytes were exposed to 0, 0.5, 1.0, 2.5 or 5.0 Gy of 60Co gamma-rays either as a T-cell suspension or as separated T cell subsets. Survival curves, determined 5 days after irradiation, revealed that each subset has radiosensitive and radioresistant portions, and that the T-G cell is the most sensitive subset. Mitotic indices of 48-h cultures showed that the response of unirradiated T lymphocytes to PHA varied greatly among the subsets, the highest indices being obtained for the T-M and the lowest for the T-G cells. With the possible exception of the T-G cells, the subsets are relatively resistant to mitotic effects of gamma-rays. T-G cells suppress the PHA-induced mitotic response of the other T lymphocyte subsets, and this suppressor effect is radiosensitive, being abolished by 1.0 Gy. It is concluded that lymphocytes exposed to greater than or equal to 1 Gy of gamma-rays will have very few dividing B lymphocytes or T-G cells. This together with radiation-induced loss of T-G suppressor action means that the predominant lymphocyte types in mitosis after greater than or equal to 1 Gy are the radioresistant T-M and T-null cells.

Cell Survival↗
PubMed1982

Enrichment of human marrow lymphocytes with monoclonal antibodies to murine antigens.

Two monoclonal antibodies, prepared against a murine B lymphoma and characterized as binding to a cell surface antigen represented primarily on cells of the B lineage, were found to bind to human hemopoietic cells. These antibodies recognize similar populations of cells in mice and humans. Antibodies from clones 177.17 and 83.4 bound to 6% of human bone marrow nucleated cells. This included all cells with detectable cell surface Ig (sIg+) and those that lack sIg but have detectable cytoplasmic mu (sIg-, c mu+), considered to be the immediate precursors of B lymphocytes (pre-B cells). In addition, these antibodies bound to a subpopulation of T cells and a proportion of null lymphocytes in marrow, spleen, and peripheral blood. An unexpected finding was that established pre-B cell lines were not recognized by these antibodies and possible reasons for this are considered. By using antibody-coated polystyrene plates for cell depletion and recovery, highly enriched preparations of c mu+, sIg- cells have been obtained. These antibodies and enrichment procedures should prove valuable in establishing the minimal requirements for maturation of these putative precursors in vitro, for comparative studies of immunodeficiency/autoimmune diseases in man and experimental animal models, and for monitoring the outcome of therapeutic marrow transplantation.

Animals↗
PubMed1978

Cellular changes in lungs of mice infected with influenza virus: characterization of the cytotoxic responses.

Transpleural lavage of lungs from uninfected C3H mice yielded an average of 300,000 leukocytes per mouse. This number increased eightfold within 6 days after intranasal inoculation with virulent influenza A/Hong Kong/68 (H3N2) virus. Macrophages and lymphocytes in approximately equal numbers comprised 90% or more of the leukocytes both before and during infection. B, T, and null lymphocytes comprised, respectively, 9, 21, and 18% of the leukocytes before infection and 7, 26, and 5% by day 6. In absolute numbers, macrophages and T lymphocytes provided the major increments during infection. Cytotoxic activity of mononuclear cells from lung lavages was compared in a chromium release assay using syngeneic L929 target cells with the activity of mediastinal lymph nodes, spleens, and peripheral blood of uninfected and infected C3H mice. Nonspecific cytotoxicity for target cells infected with H3hkNeq1 or B/Lee influenza virus was found with mononuclear cells from uninfected mice. This activity tended to be highest with lavage leukocytes and was associated with adherent cells, presumably macrophages. Increased virus-specific cytotoxicity was detected with lavage cells by day 6 and persisted through day 9, the period of maximal pneumonia. Similar cytotoxic activity also appeared in cells from the nodes and spleen at this same time but was not detected in peripheral blood cells. The virus-specific cytotoxicity of lavage cells was due largely to a nonadherent cell possessing Fc receptors and theta antigen but lacking C3 receptors; these properties are compatible with actively cytotoxic T lymphocytes. The cytological characteristics of the infiltrating leukocytes and the cytotoxicity data suggest that the local T cell response to influenza virus infection in the lung is a major contributor to the pneumonia observed in this mouse model.

Animals↗