Late-phase airway reaction and inflammation

With some exceptions, the late asthmatic response and increased airway responsiveness to methacholine or histamine are closely associated. Increased responsiveness after an allergen challenge can be reversed or prevented by appropriate anti-inflammatory treatment. To determine how the inflammatory response contributes to an increase in smooth muscle responsiveness in asthma, local hematopoietic processes were examined. In support of the mast cell hypothesis, scrapings from nasal turbinate mucosa have shown greater numbers of mast cells in patients with allergic rhinitis compared with normal subjects. Similarly, the number of metachromatic cells in bronchoalveolar lavage fluid correlates directly with methacholine-induced airway hyperresponsiveness. Since nasal polyps appear to result from inflammation of nasal mucosa, these tissues were also examined for the possible presence of progenitor cells that favor selective growth of basophil/mast cells. Since growth factors such as interleukins and cytokines stimulate cell activation, they may also contribute to ongoing inflammatory processes. Therefore substances that modify the production or actions of locally generated growth factors might be developed for the treatment of chronic inflammation of the nasal and bronchial airways.

Factors influencing basophilic differentiation of HL-60 cells

Lineage-specific hematopoietins apparently act in concert with multipotent factors in an orderly sequence of growth and differentiation. We have used the human acute promyelocytic leukemia cell line HL-60 to examine basophilic differentiation, using radioenzymatic assay of histamine content as an end point. Recombinant human interleukin 1 (rhIL-1), rhIL-2, rhIL-4, and recombinant human alpha and gamma interferons did not stimulate basophilic differentiation either in the presence or absence of sodium butyrate, an important cofactor for induction of differentiation. In contrast, rhG-CSF (granulocyte colony-stimulating factor), rhGM (granulocyte-macrophage) CSF, rhIL-3, rhIL-5, nerve growth factor, conditioned medium (CM) from the hairy T cell leukemic line Mo, and nasal polyp epithelial CM stimulated significant increases in histamine content in HL-60 cells at day 5 in vitro. GM-CSF did not account for all of the basophilic differentiating activity in Mo-CM. The data suggest that a unique, lineage-specific, basophilic cell differentiation factor is produced by T cells and point to the possible diagnostic and therapeutic relevance of in situ hematopoietic mechanisms in human respiratory disease.

A novel neuronal antigen identified by sera from patients with systemic lupus erythematosus

Using human neuroblastoma cell lines (IMR-6, NMB-7, SK-N-Mc, SK-N-SH) as sources, we characterized surface neuronal antigens as an initial step in determining the pathogenic role and clinical significance of neuronal antibodies in systemic lupus erythematosus (SLE) patients. SLE sera were screened for the presence of surface neuronal antibodies using a mixed hemadsorption assay. Thirty SLE sera were further tested by Western blotting and immunoprecipitation of lysed IMR-6 cells. Western blotting revealed binding to predominantly intracellular antigens, none of which was restricted to neuroblastoma cells. In contrast, immunoprecipitation experiments demonstrated binding to a 97K antigen, which appeared to be of surface origin, by 3 SLE sera. This was not present on non-neuronal cells and was not precipitated by sera from healthy or disease controls. This 97K antigen was also precipitated from the neuroblastoma cell line NMB-7, but was not present on SK-N-Mc or SK-N-SH cells. Precipitation was depleted by preabsorption with viable IMR-6 and NMB-7 cells, but not with non-neuronal cells. Thus, some SLE sera recognize a 97K neuronal antigen on select neuroblastoma cells.

Neuropsychological correlates of serum lymphocytotoxic antibodies in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by frequent neuropsychiatric (NP) manifestations. At least two different pathogenetic mechanisms have been proposed for NP-SLE, including vasculitis and antibodies against neuronal antigens, the latter as expressed by the presence of brain cross-reactive lymphocyte antibodies. We have previously reported a high prevalence of cognitive dysfunction in SLE which can remain subclinical and which cannot be accounted for on the basis of disease activity, general distress, or steroid medication. In the present study, we undertook the same extensive, standardized neuropsychological testing in 98 consecutive female SLE patients in order to evaluate central nervous system functioning in relation to serum lymphocyte antibodies which were measured at the time of neuropsychological testing by a microcytotoxicity test. A significant association was observed between the presence of serum lymphocytotoxic antibodies (LCA) and cognitive impairment in patients with SLE. The pattern of impairment which predominated in the LCA-positive patients involved deficits in anteriorly associated, primarily visuospatial functions. These findings support the hypothesis of localization of a particular antigen-antibody interaction in the brain in SLE, suggesting the existence of immunological control mechanisms for normal brain functioning.

Nerve growth factor promotes human hemopoietic colony growth and differentiation

Nerve growth factor (NGF) is a neurotropic polypeptide necessary for the survival and growth of some central neurons, as well as sensory afferent and sympathetic neurons. Much is now known of the structural and functional characteristics of NGF, whose gene has recently been cloned. Since it is synthesized in largest amounts by the male mouse submandibular gland, its role exclusively in nerve growth is questionable. NGF also causes histamine release from rat peritoneal mast cells in vitro, and we have shown elsewhere that it causes significant, dose-dependent, generalized mast cell proliferation in the rat in vivo when administered neonatally. Our experiments now indicate that NGF causes a significant stimulation of granulocyte colonies grown from human peripheral blood in standard hemopoietic methylcellulose assays. Further, NGF appears to act in a relatively selective fashion to induce the differentiation of eosinophils and basophils/mast cells. Depletion experiments show that the NGF effect may be T-cell dependent and that NGF augments the colony-stimulating effect of supernatants from the leukemic T-cell (Mo) line. The hemopoietic activity of NGF is blocked by polyclonal and monoclonal antibodies to NGF. We conclude that NGF may indirectly act as a local growth factor in tissues other than those of the nervous system by causing T cells to synthesize or secrete molecules with colony-stimulating activity. In view of the synthesis of NGF in tissue injury, the involvement of basophils/mast cells and eosinophils in allergic and other inflammatory processes, and the association of mast cells with fibrosis and tissue repair, we postulate that NGF plays an important biological role in a variety of repair processes.

Human nasal polyp epithelial basophil/mast cell and eosinophil colony-stimulating activity. The effect is T-cell-dependent

We have previously reported highly potent basophil/mast cell (BMC) and basophil/eosinophil (Eo) colony-stimulating activities (CSA) in conditioned medium derived from cultured human nasal polyp epithelial scrapings (NP-CM). We now have examined the involvement of peripheral blood T-cells in the NP-CM stimulation of colony-forming units (cfu) from the blood of atopic and nonatopic subjects. Because the number of BMC- and Eo-cfu was significantly higher in cultures of peripheral blood from subjects with out-of-season ragweed allergic rhinitis than from control subjects (23.8 +/- 4.1 versus 9.0 +/- 2.4, p less than 0.01), we asked whether the observed colony stimulation could be a T-cell-dependent effect. Indeed, peripheral blood target cells consisting of a reconstituted mixture of T-cells and T-cell-depleted peripheral blood mononuclear cells (non-T-cells) yielded a significantly higher number of colonies in the presence of NP-CM than the non-T-cells alone. NP-CM did not stimulate colony formation by isolated T-cells. These observations point to interactions among nasal epithelial growth and differentiation factors, blood-borne progenitors and T-cells in the local accumulation of basophils, mast cells, and eosinophils in nasal polyps.

Allergic rhinitis nasal mucosal conditioned medium stimulates growth and differentiation of basophil/mast cell and eosinophil progenitors from atopic blood

In previous studies of human nasal polyps and nasal mucosa from subjects with allergic rhinitis, we have demonstrated hematopoietic progenitors, measured as colony-forming units (CFU) in culture, and colony-stimulating activities for basophil/mast cells (BMC) and basophil/eosinophils (Eo). In the present study, conditioned medium (CM) from short-term cultures of nasal mucosal scrapings of subjects with allergic rhinitis are compared with those from normal subjects for colony-stimulating activities, with BMC and Eo CFU in methylcellulose assays of peripheral blood from atopic (N = 6) or nonatopic (N = 6) individuals. CM derived from cultures of nasal mucosal scrapings from subjects with allergic rhinitis stimulated a significantly greater number of BMC/Eo CFU from the peripheral blood of atopic (out-of-season and ragweed-allergic) subjects than from peripheral blood of nonatopic subjects in a series of matched-control experiments (20.6 +/- 4.6 versus 1.9 +/- 0.8; p less than 0.002); in contrast, nasal mucosal CM from normal control subjects did not stimulate an increase in these CFU in peripheral blood from atopic compared to nonatopic subjects. These studies further support the hypothesis that in situ hematopoietic mechanisms are operative in allergic inflammatory reactions and suggest the presence of cells in affected (allergic) epithelium that are "activated" to produce large amounts of BMC and Eo growth and differentiation factors.

Intranasal nedocromil sodium in the treatment of ragweed-allergic rhinitis

Nedocromil sodium (NS), a new pyranoquinoline dicarboxylic acid derivative, reported to be effective against both mucosal and connective tissue-type mast cells, was studied in ragweed-allergic rhinitis (RAR). Thirty-six patients with RAR were studied in an 8-week, double-blind, placebo-controlled trial. Stratification was based on prick skin test sensitivity and severity of signs and symptoms of previous RAR. NS (1% solution) in a dose of 0.13 ml of nasal spray was administered to each nostril, a minimum twice daily. Concomitant medications were limited to ingested terfenadine, ocular cromolyn, and inhaled medications. Symptoms and medications were noted daily. Active-treatment and placebo-treatment groups were comparable. There were less symptoms of runny nose and itchy eyes in the active-treatment group (p less than 0.05) and also less antihistamine, p less than 0.004. Patients in the active-treatment group were more likely to conclude that symptoms were improved by the nasal spray (p less than 0.01). No side effects were reported. This study indicates that NS is effective and well tolerated in RAR.

Prognostic implications of basophil differentiation in chronic myeloid leukemia

Basophilia has been reported to indicate an accelerated phase of chronic myeloid leukemia (CML), heralding a poor prognosis. We have studied 47 patients with chronic-phase CML by basophil growth and differentiation assays in vitro, demonstrating an association between basophil growth index (BGI) and clinical time to blast crisis as well as overall survival. In addition to confirming an association between positive BGI and phase of CML in a larger group of patients, a positive BGI predicted death or blast crisis within 2 years' study of chronic phase CML (p less than 0.01), with a sensitivity of 78%, specificity, 81%; the positive predictive value of a positive test, 64%; and a negative predictive value of a negative test, 89%. The survival experience of the 22 evaluable patients with chronic-phase CML and a positive BGI was significantly worse than the survival of the 19 patients with a negative BGI (p less than 0.0001). At 1, 2, and 3 years the proportion of surviving patients with a positive BGI was 0.64, 0.32, and 0.23, respectively, compared with 1.00, 0.90, and 0.79 for those with a negative BGI. The median survival of chronic phase CML patients with a positive test at diagnosis (n = 14) was 27 months versus 54 months for those with a negative diagnosis (n = 14) (p less than 0.05). These findings emphasize the prognostic utility of basophil growth assays in CML and suggest a molecular relationship between leukemic transformation and basophil lineage expression.

Human basophilic cell differentiation promoted by 2.5S nerve growth factor

In liquid cultures of human cord blood mononuclear cells, the activities of the 2.5S nerve growth factor (NGF) inducing basophil and eosinophil differentiation were investigated. Various concentrations of immunopurified 2.5S NGF derived from murine submaxillary glands were added to cultures with or without conditioned medium from a human T cell line (Mo-CM), which has previously been shown to produce activities stimulating granulocyte-macrophage colonies. Addition of NGF led to significant increases in differentiation of basophilic cells accompanied by histamine synthesis at 2 weeks in vitro; eosinophil differentiation was not increased in these cultures. In addition, NGF could be shown to amplify basophil differentiation induced by Mo-CM, and the activity of NGF inducing basophil differentiation was dependent on the presence of T lymphocytes. These results indicate that NGF stimulates T-lymphocyte-dependent basophilic cell differentiation from human cord blood progenitors and may in this way support differentiation of basophils or mast cells in vivo at sites of allergic tissue inflammation.

Sodium butyrate and a T lymphocyte cell line-derived differentiation factor induce basophilic differentiation of the human promyelocytic leukemia cell line HL-60

Sodium butyrate induces basophilic differentiation of HL-60 promyelocytic leukemia cells that have been previously passaged in alkaline medium. A factor present in Mo conditioned medium (Mo-CM) acts synergistically with sodium butyrate to promote basophilic maturation in a dose-dependent fashion. The induced HL-60 cells exhibit nuclei at various stages of maturity and cytoplasmic granules staining azurophilic with May-Grünwald-Giemsa and metachromatically with toluidine blue. The histamine content of induced HL-60 cells is 50 ng/10(6) cells with sodium butyrate alone or 190 ng/10(6) cells with butyrate in combination with Mo-CM. Induced cells release histamine in response to anti-IgE and have receptors for the Fc portion of human IgE. The basophilic cell-differentiating activity present in Mo-CM appears to be distinct from several other cytokines including recombinant human interleukin-1 alpha, interleukin-2, interferon-gamma, interferon-alpha, murine interleukin-3, erythroid-potentiating activity, and purified human granulocyte/macrophage colony-stimulating factor. This is the first demonstration of a cell line that is capable of differentiation along the basophil lineage and could provide a useful model for examining biochemical and molecular events associated with basophil differentiation.

Neuropeptides and immunity

Our studies have clearly shown that neuropeptides have a profound effect on immunoglobulin synthesis both in vivo and in vitro. The effects varied according to the neuropeptide added or the tissue from which the lymphocytes were obtained. Substance P caused the most pronounced enhancement of both functions, especially in Peyer's patch cells, where it selectively increased IgA synthesis. Somatostatin was inhibitory, and the effect of vasoactive intestinal peptide varied according to the source of the cells. We have previously shown that neuropeptides also cause mast cell secretion and that only substance P was effective in this regard on intestinal mucosal mast cells. Therefore, we looked for microanatomic relationships between peptidergic nerves and immune effector cells. Mast cells appear to have structural associations with neuropeptides-containing nerves in the intestine. Nerve growth factor, known to promote the growth of sensory afferent and sympathetic nerves, has significant direct effects on mast cells. In vitro, this substance caused enhanced antigen mediated histamine release and, in vivo, extensive mast cell hyperplasia. Also, in humans, we were able to produce increased numbers of mast cell/basophil colonies from peripheral blood in the presence of nerve growth factor.

Hypogammaglobulinemia: therapeutic rationale

Hypogammaglobulinemia is a feature of several B-cell disorders and is manifested clinically by recurrent infection, most commonly chronic upper and lower respiratory tract disease. Immunoglobulin replacement therapy is available, with at least four different routes of administration. There are as yet no convincing data that allow comparison of the cost-effectiveness of these methods. However, by individualizing therapy for each patient, it is possible to prevent life-threatening acute infections, reduce the severity of chronic upper and lower respiratory tract disease, improve pulmonary function and achieve normal levels of IgG. These are the currently acceptable goals of therapy in patients with hypogammaglobulinemia.

Metachromatic cell progenitors and specific growth and differentiation factors in human nasal mucosa and polyps

We previously demonstrated that fluctuations in circulating metachromatic cell progenitors were inversely related to nasal metachromatic cell (NMC) counts and nasal symptoms in allergic rhinitis. Now, we have quantitated NMC progenitors and lineage-specific growth factors using a hemopoietic colony assay. Cell suspensions from excised collagenase-treated nasal polyps (n = 7) contained 3.8 +/- 1.1 granulocyte colony-forming cells per 10(6) cells plated, compared to less than or equal to 0.5 in human tonsil suspensions, less than or equal to 0.5 in nasal mucosal epithelial scrapings, and 33 +/- 8 in peripheral blood of patients with ragweed allergic rhinitis (p less than 0.01). The percentage of metachromatic cells in nasal-polyp-derived colonies was 47 +/- 10 compared with 3.0 +/- 0.7 in peripheral blood colonies (p less than 0.005). Highly potent metachromatic cell colony-stimulating activity (CSA) was detected in supernatants from cultured human nasal epithelial scrapings from both polyps and atopic nasal mucosa, but not from nonatopic nasal mucosa. Supernatants from polyp mononuclear cells stimulated with phytohemagglutinin also contained metachromatic cell-CSA, which had an approximate molecular size of 25 to 70,000 daltons on column chromatography. An IL-3-like activity was also detected in these supernatants. These observations provide further evidence for in situ hemopoietic mechanisms in human nasal mucosa, involving epithelium-derived stimulation of local metachromatic cell progenitor growth and differentiation in allergic rhinitis.

Cerebrospinal fluid immunoglobulins and neuronal antibodies in neuropsychiatric systemic lupus erythematosus and related conditions

Neuronal antibodies found in the cerebrospinal fluid (CSF) of patients with systemic lupus erythematosus (SLE) may be locally produced, or may enter through a damaged blood-brain barrier. We measured CSF serum/albumin and IgG ratios, oligoclonal banding, and paired CSF/serum neuronal antibody in 36 patients and 98 controls. Only 14% of SLE CSF contained neuronal antibodies; 80% of these had clinically overt neuropsychiatric manifestations. None of 73 patients with noninflammatory central nervous system (CNS) disease had CSF-neuronal antibodies, compared with 8/61 with SLE or related inflammatory CNS disorders (p less than .001). In SLE, CSF neuronal antibodies were accompanied by high titer serum neuronal antibodies (p less than 0.03) or abnormal Q-albumin and occurred only when serum neuronal antibodies were present. CSF-neuronal antibodies appear to be related to immune-inflammatory CNS disease, especially SLE, and may traverse a damaged blood-brain barrier.

Cognitive impairment in systemic lupus erythematosus: a neuropsychological study of individual and group deficits

Eighty-six females with systemic lupus erythematosus (SLE) were grouped according to present or past history of neuropsychiatric (NP) symptomatology (Active, Inactive, or Never). Performance of these three groups was compared to that of 35 normal women on an extensive battery of neuropsychological tests sampling a wide range of cognitive functions. In addition to making group comparisons, we also devised a system for identifying individual impairment using decision rules for both quantitative and qualitative data. Our results indicate that a variety of cognitive deficits are present in SLE patients taken together as a group; there is no significant association between cognitive impairment and emotional disturbance; patients with resolved NP symptomatology are as impaired as patients with active NP symptoms, suggesting residual CNS involvement; in spite of no significant difference emerging on direct group comparisons, significantly more Never NP-SLE patients are impaired than are controls on several summary scores, suggesting subclinical CNS involvement in these patients.

Mast cell involvement in various inflammatory processes

Mast cells from different tissue sites may have different histochemical, chemical, and functional properties. Whatever the basis for these differences, they must be important in terms of their biologic significance. Through their mediators, mast cells are involved in many different acute and chronic inflammatory processes. They act in delayed hypersensitivity, immediate hypersensitivity, and in granulomatous reactions. They can influence phagocytosis, chemokinesis, and many aspects of immune activity in several different T and B cell pathways, to mention only a few effects. Mast cells are involved in repair processes including fibroblast function and fibrosis. Their growth may be influenced by T cell-derived factors as well as factors derived from the epithelium. They appear to be intimately involved with nerves and can form apparent communications with neurones, especially those containing Substance P, which causes all types of mast cells to degranulate. Mast cells may therefore act as central switchboards between the central nervous system and migrating and sessile cell types in inflammatory processes.

Neuronal antibodies and cognitive function in systemic lupus erythematosus

The pathogenesis of neuropsychiatric lupus (NP-SLE) is unclear, but may involve vasculopathy, antibodies against nervous system tissue, or both. A major difficulty in determining the significance of antineuronal antibodies in NP-SLE has been lack of consistent clinical diagnostic approaches. By utilizing a new clinical classification of NP-SLE, neuropsychological assessments, and an assay for IgG antineuronal antibodies, we have found a significant association between antibody-positivity and cognitive impairment or nonfocal NP-SLE. These observations indicate that antineuronal antibodies may play a role in NP-SLE and emphasize the clinical importance of cognitive function in patients with SLE.

Contribution of basophil/mast cell and eosinophil growth and differentiation to the allergic tissue inflammatory response

The mechanisms underlying allergic tissue basophil/mast cell (BMC) or eosinophil (Eo) accumulation are unclear, especially since chemotaxis or IgE levels do not offer a sufficient explanation. We have found that a formaldehyde-blockable, steroid-responsive nasal metachromatic cell (NMC) population predominates in epithelium and correlates well with symptoms and signs in patients with allergic rhinitis. Circulating BMC and Eo progenitors (colony-forming cells in culture; CFU-c) are increased in atopic patients, inversely related to NMC counts, and fall as NMC numbers rise during seasonal allergen (ragweed pollen) stimulation. The metachromatic cell progeny of these CFU-c are also formaldehyde-blockable in their staining reaction and thus may correspond to NMC. Human nasal polyps yield BMC CFU-c. Nasal polyp epithelial scrapings or mononuclear cells, T lymphocytes or keratinocytes in vitro all produce potent BMC or Eo colony-stimulating activities (CSA) as well as an interleukin-3-like activity, each of which is partially separable from the others. Nasal epithelial cells cultured from scrapings of atopic, as opposed to nonatopic, patients also produce BMC or Eo CSA with an enhanced effect of the former on atopic peripheral blood CFU-c growth. These studies support the hypothesis that BMC and Eo accumulate in allergic inflammation as a result of in situ growth and differentiation of progenitors stimulated by soluble hemopoietic factors derived from mucosal cell populations.

Reciprocal regulation of human basophil and eosinophil differentiation by separate T-cell-derived factors

Basophil and eosinophil progenitors are present in human hemopoietic tissues, including cord blood. In the present studies, cord blood cultures demonstrating differentiation of basophils or eosinophils have been maintained for prolonged periods in the presence of conditioned medium from a human T-cell leukemia line (Mo-CM). Peak basophil counts and histamine levels were followed almost invariably by a second peak of eosinophils in vitro. Morphologic examination revealed the consistent presence of cells with mixed basophil-eosinophil granulation. Both basophil and eosinophil growth-stimulating activities were found in Mo-CM, were heat stable and nondialyzable, and could be partially separated from each other by a multistep procedure that included ion-exchange chromatography on DEAE-cellulose. Mixing experiments using separated basophil- and eosinophil-stimulating activities revealed that suppression of basophil growth was accompanied by reciprocal enhancement of eosinophil growth, a finding that could be confirmed on analysis of morphology of single colonies from cord blood progenitors in methylcellulose. These studies point to the existence of regulatory growth factors in Mo-CM that stimulate and/or inhibit the growth and differentiation of human basophils and eosinophils from a common, committed progenitor cell.

The role of mast cells in inflammatory processes: evidence for nerve/mast cell interactions

In the rat, there is considerable evidence of mast cell/nerve interaction both in the normal and infected intestine. Between 67 and 87% of all mast cells in the intestinal lamina propria of rats infected 22-35 days earlier with Nippostrongylus brasiliensis were touching nerves. These membrane contacts were between subepithelial mast cells and nonmyelinated nerves containing substance P, calcitonin gene-related peptide and neurone specific enolase. 2.5S nerve growth factor (NGF) has a significant enhancement effect on antigen-induced histamine release without addition of phosphatidylserine, and the in vivo administration of NGF to rats causes both connective tissue and mucosal mast cells to dramatically increase in number. All of these effects are both dose dependent and NGF specific, as evidenced by inhibition with anti-NGF. 2.5S NGF also causes in vitro increase of colonies in methylcellulose cultures of human peripheral blood. The effects of NGF in this system are synergistic with other T cell-derived growth factors and relatively specific for metachromatic cell growth. These observations support the conclusions that nerves and mast cells may constantly communicate and provide a structural and conceptual framework whereby the central nervous system may communicate with inflammatory events.

Human interleukin-3-like activity, basophil and eosinophil growth promoting activities and colony stimulating factor derived from several cell lines

Human IL-3-like activity, colony stimulating factor (CSF) and basophil/eosinophil growth promoting activity (Ba/Eo GPA) in serum-free conditioned media (CM) derived from various cell lines of human origin were examined. Squamous cell carcinoma (Colo-16), osteogenic sarcoma (R97KL4) and human placental (HP) cells produced 10-20% IL-3 activity present in supernatants from a mouse myelomonocytic cell line (WEHI-3BCM) when assayed using a murine IL-3 dependent cell line (32Dcl/H4). The human T-cell leukemic cell line (Mo) and several neuroblastoma cell lines did not produce IL-3-like activity, nor did purified human erythroid potentiating activity (EPA) from Mo contain IL-3. CSF and Ba/Eo GPA were detected in CMs from Mo, HP, Colo-16 but not from R97KL4. No IL-2 activity was detected in any of these CMs. These observations point to the existence of diverse sources of human IL-3-like activity and to the probable distinctiveness of human IL-3, basophil or eosinophil GPA, and EPA. Analogies drawn between human and murine hemopoietic activities need to be made with caution.

Human lung mast cells: distribution and abundance of histochemically distinct subpopulations

Methods originally employed to demonstrate the heterogeneity of mast cells in the rat and more recently in the human intestine were used to study mast cell heterogeneity in the human bronchial mucosa and lung parenchyma. Thus, a quantitative survey of pulmonary mast cells using different fixation and staining procedures indicated that two distinct mast cell subpopulations (formalin-sensitive and formalin-resistant) are present and have distinct patterns of distribution and abundance. The findings are of potential clinical importance because histochemical heterogeneity may be a marker of functional mast cell differences in humans including differences in responsiveness to antiallergic drugs, as occurs in rats. The findings also indicate that conventional methods of fixation are likely to lead to a gross underestimation of total mast cell numbers.

Stimulation of maturation of large immature histamine-containing basophilic cells from human peripheral blood, cord blood and bone marrow

The development of FcR epsilon-bearing histamine-containing basophilic cells was studied in cultures of peripheral blood leucocytes and bone marrow leucocytes from normal individuals. The determination of basophilic cells was performed blindly. Before cultivation there were fairly similar numbers of basophilic cells in the samples from the three different sources (1.6 +/- 1.6 n = 13; 1.4 +/- 2.0 n = 21; 4.3 +/- 4.7 n = 8, respectively). During cultivation spontaneously appearing large blast-like basophilic cells were seen in good correspondence with a formation of histamine in the cultures (Spearman rank correlation coefficient = 0.9135, n = 13, P less than 0.001). This was more accentuated with bone marrow cells than with peripheral blood and cord blood cells. Conditioned medium (CM) was prepared from cells isolated from various tissues and stimulated by different means, e.g. peripheral blood from atopic individuals stimulated with allergen and unstimulated tonsil cells. Addition of the CM resulted in increased development of histamine-containing basophilic cells. Optimum stimulation was achieved with 10% CM. The basophilic stimulation by CM, as assessed as indices vs. unstimulated cultures, was more accentuated in cultures of peripheral blood cells than of bone marrow and cord blood cells (2.8 +/- 1.2; 1.8 +/- 0.5; 2.0 +/- 0.4, respectively). In contrast, the histamine formation was particularly evident in stimulated cultures of bone marrow cells, where more than four-fold increases of histamine were found. In bone marrow cells the histamine levels per basophilic cell also increased, whereas this was not the case in cord blood cells. A pronounced development of basophilic cells was achieved when using leukoagglutinin, provided the mitogen in the CM was eliminated. The formation of basophilic cells was prevented with mitomycin c and cycloheximide. In conclusion, the system described may provide important information on the development of histamine-containing basophilic cells at various maturation stages from different compartments, and mechanisms in a developing atopic disease.

Effect of beclomethasone dipropionate on nasal metachromatic cell sub-populations

The effect has been investigated of local administration of beclomethasone dipropionate (BDP) on cell numbers of nasal epithelial metachromatic cell (NMC) sub-populations. Twenty-one patients with perennial allergic rhinitis were studied in four groups according to the duration of treatment or after treatment with BDP. Nasal scrapings were taken after 1 week (Group 1) or 2 weeks (Group 2) of BDP treatment, or after discontinuing BDP for 1 week (Group 3) or 2 weeks (Group 4). Cells were fixed with Mota's lead acetate or 10% buffered formalin followed by toluidine blue staining to count the number of NMC and to classify these according to morphological sub-types (basophils or mast cells). Formalin-sensitive mast cells and basophils in nasal scrapings were reduced more than formalin-resistant mast cells with BDP treatment. Formalin-sensitive mast cells were also more prompt to recover from BDP than formalin-resistant mast cells. The results suggest that the formalin-sensitive NMC is a sub-population of cells which responds to BDP treatment in allergic rhinitis.

Long term growth of factor-producing lymphoid and myeloid cells in serum-free medium

The ability to grow lymphoid and myeloid cells in serum-free culture medium allows researchers to analyze the factors and mechanisms required for hemopoietic cell growth and differentiation without the interference of undefined serum components. Therefore, we used a serum-free medium, RITC 55-9 that consisted of modified Dulbecco's MEM supplemented with bovine serum albumin (BSA), transferrin (Tf) and insulin (Ins) to culture human T lymphoid (Mo), murine myelomonocytoid (WEHI-3B) and murine interleukin (IL)-3-dependent (32Dcl/H4) cell lines. Mo was maintained in RITC for more than 8 months and had a mean viability of 59% and the same doubling times as in serum-containing medium (SCM). Under these conditions, Mo cells produced hemopoietic colony-stimulating activity that included production of a basophil/eosinophil differentiation factor of similar content to that produced in SCM. WEHI-3B cells grown for more than 12 months in RITC, or for more than 3 months in RITC without Tf and Ins, had a doubling time of 20 h, whereas cells maintained in protein-free RITC showed a 2-fold increase in doubling time then died within 3 months. The IL-3 production by WEHI-3B cells cultured in RITC was higher than the production by cells grown in SCM. When IL-3 was assayed in 32Dcl/H4 cells that had been maintained in RITC for more than 4 months, a lower response to IL-3 was found, an indication that components other than the BSA, Tf and Ins in fetal calf serum are required for optimal cell growth and differentiation.

Basophilic cell progenitors, nasal metachromatic cells, and peripheral blood basophils in ragweed-allergic patients

Circulating hematopoietic progenitor cells giving rise to colonies containing basophilic cells (basophilic cell colony-forming units in culture [CFU-c]), nasal epithelial metachromatic cells (basophils and/or mast cells) (NMC), and blood basophils were enumerated before, during, and after a ragweed-pollen season in patients with ragweed hayfever and patients with perennial allergic rhinitis who were not ragweed allergic. In the patients with seasonal hay fever, the following was observed: basophilic cell CFU-c, measured as basophilic cell or histamine-containing colonies, were significantly reduced during the ragweed season compared to before (p less than 0.005) or after (p less than 0.025) the season in the ragweed-allergic group only. Conversely, peripheral blood basophils were higher during the ragweed season than before or after (p less than 0.001) in the ragweed-allergic group, whereas the number of NMC was higher during the season than before the season in this group (p less than 0.05). There were no such changes during the season in the group of patients with perennial allergic rhinitis. The observed seasonal changes in both NMC and circulating basophilic cell CFU-c are discussed in the context of lineage relationships among metachromatic cell types.

Serum basophil-stimulating activity in the guinea-pig during induction of basophilic responses to ovalbumin and tick feeding

We have described functional and biochemical characteristics of a distinct T-cell dependent guinea-pig basophil-stimulating factor (BSF), measured using a sensitive 7-day bone marrow culture assay, standardized with high-activity BSF present in serum-free splenic cell-conditioned medium (CM). In the present studies, the in vivo relevance of BSF was explored during protocols of induction of peripheral blood or tissue basophil responses to ovalbumin (OA) injection or Amblyomma americanum tick feeding. Pooled immune serum, taken from OA-injected inbred or outbred animals during induction of blood and marrow basophilia, contained an in vitro inhibitor to BSF at high concentrations and BSF-like activity at low concentrations; maximal stimulation of histamine synthesis by bone marrow cells in vitro was found in the presence of Day 4 OA-immune serum. In vivo studies in the OA model demonstrated maximal serum BSF-like activity at 48-72 hr before peak bone marrow basophil response, followed by a levelling off to 50% of maximum at 2 weeks. In the tick model, serum BSF-like activity was present in Day 8, but not Day 1, post-primary infection and was maximal at Day 3 post-secondary infection; post-primary Day 1 serum was inhibitory to basophil growth in vitro. These observations suggest that BSF regulates the appearance of basophils in response to antigen in vivo by an effect on basophil progenitors. The observations stress the potential application of guinea-pig models to understanding the regulation of basophil production in allergic disorders.

Prevalence of cognitive impairment in systemic lupus erythematosus

We administered a battery of neuropsychological tests to 62 female patients with systemic lupus erythematosus (SLE), 12 female patients with rheumatoid arthritis (RA), and 35 normal control subjects. By applying objective decision rules to individual test protocols, an overall prevalence of cognitive impairment of 66% was obtained in the SLE patient sample. Independent clinical, radiological, and laboratory data were used to determine neuropsychiatric (NP) symptomatology and to group SLE patients as 1) "active" (N = 21), 2) "inactive" (N = 15), and 3) "never" (N = 26) NP-SLE. More than 80% of the patients in groups 1 and 2 and 42% in group 3 showed significant cognitive impairment as compared with 17% of the RA patients and 14% of the normal control subjects. Neither steroid medication nor psychological distress could account for these findings. The unexpectedly high prevalence of cognitive impairment in SLE patients with either inactive or absent neuropsychiatric symptomatology provides evidence for subclinical nervous system involvement in SLE.

Peripheral blood basophils, basophil progenitors, and nasal metachromatic cells in allergic rhinitis

Relationships among mature blood basophils, blood basophil colony-forming units in culture (CFU-c), and nasal metachromatic cells (NMC) were investigated using hemopoietic and histochemical techniques in 29 patients with allergic rhinitis and in 7 nonatopic control subjects. Total blood granulocyte and basophil CFU-c were significantly elevated in atopy; the highest levels of basophil CFU-c were found in patients with low total NMC counts in nasal scrapings (Group I), compared with those with intermediate (Group II) or high (Group III) counts: 10 +/- 3 basophil CFU-c per 10(6) cells in 10 Group I patients, 4 +/- 2 in 10 Group II patients, 3 +/- 1 in 9 Group III patients, and 0.1 +/- 0.1 in nonatopic control subjects (p less than 0.05). Mean histamine content and frequency of histamine-positive granulocyte colonies correlated with counts of basophils in colonies (r = 0.864, p less than 0.001). Peripheral blood basophils, which stained metachromatically with toluidine blue at pH 0.5 after Mota's lead acetate but not after formalin fixation, were highest in atopic Group III and lowest in Group I; a similar relationship was observed only for NMC, which also failed to stain after formalin fixation. Metachromatic cells in colonies were similar to formalin-sensitive NMC and to peripheral blood basophils in their sensitivity to different fixatives. Nasal symptoms correlated inversely with the number of basophil CFU and directly with the number of either formalin-sensitive NMC or peripheral blood basophils. These findings confirm and extend evidence for increased nasal metachromatic cells, basophilia, and alterations in basophilopoiesis in atopy.

Functional characterization of mast cells generated in vitro from the mesenteric lymph node of rats infected with Nippostrongylus brasiliensis

We have examined the biochemical and functional characteristics of mast cells grown in tissue culture from the mesenteric lymph node (MLN) of rats infected with the nematode Nippostrongylus brasiliensis and compared them with mast cells isolated from the small intestinal mucosa and peritoneal cavity of infected animals. Cultured mast cells (MC) and isolated intestinal mucosal mast cells (MMC) had a similar histamine content, and both contained type II protease (RMCP II) which was absent from peritoneal mast cells (PMC). PMC, MMC and cultured MC each responded to immunologically induced histamine secretion, but MMC and cultured MC were hyporesponsive to calcium ionophores and unresponsive to widely used PMC secretagogues including compound 48/80 and bee venom peptide 401. MMC and cultured MC also differed from PMC in their lack of responsiveness to the anti-allergic agent disodium cromoglycate. Thus, MC cultured from the MLN are distinct from PMC but have a biochemical and functional phenotype similar to that of intestinal MMC.

In vitro appearance of large human histamine-containing basophilic cells

The appearance of large human basophilic cells containing histamine was followed to reflect cell maturation in cultures of peripheral blood leukocytes. Aliquots were taken on day 0 and after 7, 9-10 and 14 days in culture, and the basophilic cell numbers were determined in 200 microliter cytospin specimens stained with Wright's stain. The number of small basophils initially present declined during the culture period. The number of spontaneously appearing large basophilic cells varied among the cultures from different individuals and was slightly, though not significantly, higher in atopic individuals than in normals. In cultures of cells from atopic individuals, the number of large basophilic cells was reproducibly increased by the addition of appropriate allergen to the cultures. In cultures of cells from normal individuals, the number was increased two- to six-fold by adding conditioned medium (CM), either from 3-day cultures of cells from atopic individuals stimulated with allergen or with CM from the Mo T cell leukemic line. The addition of mitomycin C decreased the number of large basophilic cells and cycloheximide abrogated their appearance.

Partial separation and functional characterization of guinea pig basophil-stimulating factor

We have previously described T lymphocyte dependent guinea pig basophil growth from bone marrow precursors in vitro. In the current studies, basophil-stimulating factor (BSF) present in mitogen-stimulated splenic conditioned medium (CM) has been functionally characterized, utilizing an assay for BSF on nonadherent bone marrow target cells. BSF was found to be heat stable, nondialyzable, and inactivated by proteases. Monosaccharides known to inhibit guinea pig lymphokines yielded a unique profile of inhibition of BSF activity and nonidentity of BSF with guinea pig migration inhibition factor, interleukins 1 or 2, and granulocyte-macrophage colony-stimulating activity, from which BSF could be separated after gel filtration. BSF-containing CM also had no detectable interleukin-3 activity as measured in a murine assay. An inverse relation was found between interleukin 2 and BSF production by peritoneal exudate T cells (PEL) stimulated with antigen. Fractionation of serum-containing and serum-free CM demonstrated a molecular size for BSF of 50,000-65,000 daltons. Guinea pig BSF is a distinct T cell dependent lymphokine with an active protein moiety which may interact with target bone marrow cells through a cell surface carbohydrate receptor.

Increased numbers of circulating basophil progenitors in atopic patients

Recruitment of basophils to sites of homocytotropic antibody-mediated hypersensitivity reactions has been well documented in both experimental and clinical situations. Mechanisms underlying tissue basophil accumulation, however, remain unclear and may involve chemotaxis, cell proliferation, or both. We have recently reported the presence in human blood of circulating basophil/mast cell progenitors on the basis of histamine content of granulocyte colonies grown in methylcellulose. In the current studies we have analyzed the peripheral blood of 30 patients with atopy and 25 comparable control subjects for frequency of basophil/mast cell progenitors by analysis of the histamine content of individual granulocyte colonies. Forty percent of granulocyte colonies in cultures of atopic patients contained histamine in comparison to only 11% in cultures of control subjects (p less than 0.001). Histamine content per colony as well as mean histamine per cell in each colony was higher in granulocyte colonies of atopic subjects and could not be related to colony size or culture conditions. Granulocyte colony growth was enhanced by antigen-stimulated, peripheral blood lymphomononuclear cell--conditioned media of atopic patients. Histamine-positive colonies were found more frequently in active versus quiescent atopic disease (p less than 0.05). These results are consistent with the hypothesis that basophils accumulate at sites of allergic reactions at least in part by recruitment of progenitors from circulation and subsequent differentiation in situ in response to lymphokines. Further studies by use of hemopoietic assays could elucidate the contribution of basophil production to the development of allergic conditions.

Heterogeneity of human peripheral blood eosinophil-type colonies: evidence for a common basophil-eosinophil progenitor

We have recently shown that a proportion of previously designated human eosinophil "(Eo)-type" colonies in methylcellulose contain basophils and histamine (Denburg et al Blood 61:775, 1983). In the present studies, individual Eo-type colonies have been analyzed by cell morphology as well as by biochemical assays for histamine, Charcot-Leyden crystal protein (CLC), and eosinophil granule major basic protein (MBP). Clonal origin of single Eo-type colonies was confirmed by G6PD isoenzyme analysis. Morphological observations of such colonies revealed the existence of two distinct colony types: (1) Eo type containing 100% basophils and (2) Eo type containing mixtures of basophils and eosinophils, including cells with mixed basophil-eosinophil granulation. Histamine was not detected in pure, mature peripheral blood eosinophils. Immunofluorescent studies demonstrated bright staining for CLC and MBP in 95% +/- 3% of cells in Eo-type colonies but only in 5% +/- 4% of cells in GM-type colonies. Radioimmunoassay for MBP was positive in 5/9 Eo-type and 0/10 neutrophil-macrophage ("GM-type") colonies, with a mean level (nanogram/colony) of 11.6 +/- 4.2 per Eo-type colony; four of the latter colonies were doubly positive for both histamine and MBP. These and previous findings point out the morphological and biochemical heterogeneity of peripheral blood Eo-type colonies and provide direct evidence for the existence of a common, circulating basophil-eosinophil progenitor.

Mast cell heterogeneity: effects of neuroenteric peptides on histamine release

Recent reports suggesting that the actions of certain neuroenteric peptides may be mediated in part by the secretion of histamine and other mast cell contents could have important implications for gastrointestinal motility and secretion. However, evidence for a mast cell-hormonal interaction is based on studies using peritoneal or cutaneous mast cells. Because intestinal mucosal mast cells (MMC) differ functionally from peritoneal mast cells (PMC), we compared the effects of several neurotransmitters and intestinal hormones on histamine secretion from two mast cell types in the rat. MMC hyperplasia was induced in rats by infection with the nematode Nippostrongylus brasiliensis, and MMC were isolated from the small intestine by collagenase digestion. Substance P, somatostatin, vasoactive intestinal polypeptide (VIP), neurotensin, and bradykinin had a potent secretagogue effect on (10(-7) to 10(-4)M) PMC which was temperature-, energy-, and calcium-dependent. In contrast to PMC, MMC released significant amounts of histamine only when challenged with substance P. Acetylcholine, bombesin, motilin, and pentagastrin had no secretory effect on either PMC or MMC. The differences between PMC and MMC in responsiveness to peptides could not be attributed to the MMC isolation procedure because PMC treated similarly or mixed with MMC suspensions retained their responsiveness to these stimuli. Our results extend the concept of neurocrine control of mast cell function, but indicate that mast cells from different sites have distinct profiles of responsiveness to regulatory peptides.

Mast cell heterogeneity: effects of neuroenteric peptides on histamine release

Recent reports suggesting that the actions of certain neuroenteric peptides may be mediated in part by the secretion of histamine and other mast cell contents could have important implications for gastrointestinal motility and secretion. However, evidence for a mast cell-hormonal interaction is based on studies using peritoneal or cutaneous mast cells. Because intestinal mucosal mast cells (MMC) differ functionally from peritoneal mast cells (PMC), we compared the effects of several neurotransmitters and intestinal hormones on histamine secretion from two mast cell types in the rat. MMC hyperplasia was induced in rats by infection with the nematode Nippostrongylus brasiliensis, and MMC were isolated from the small intestine by collagenase digestion. Substance P, somatostatin, vasoactive intestinal polypeptide (VIP), neurotensin, and bradykinin had a potent secretagogue effect on (10(-7) to 10(-4)M) PMC which was temperature-, energy-, and calcium-dependent. In contrast to PMC, MMC released significant amounts of histamine only when challenged with substance P. Acetylcholine, bombesin, motilin, and pentagastrin had no secretory effect on either PMC or MMC. The differences between PMC and MMC in responsiveness to peptides could not be attributed to the MMC isolation procedure because PMC treated similarly or mixed with MMC suspensions retained their responsiveness to these stimuli. Our results extend the concept of neurocrine control of mast cell function, but indicate that mast cells from different sites have distinct profiles of responsiveness to regulatory peptides.

Antineuronal antibodies in neuropsychiatric systemic lupus erythematosus

The diagnosis of neuropsychiatric systemic lupus erythematosus (NP-SLE) is clinical and one of exclusion. Brain cross-reactive lymphocytotoxins or neuronal antibodies have been proposed as a mechanism underlying NP-SLE. We assessed the clinical relevance of neuronal cell binding antibodies using a standardized clinical definition of NP-SLE. Serum from 54 SLE patients and 77 controls were tested for binding to 3 neuroblastoma and 3 glioblastoma cell lines. Thirty-three SLE patients (61%) fulfilled clinical criteria for the diagnosis of NP-SLE; of these, 55% had serum binding activity to both neuroblastoma and glioblastoma cell lines, compared with 33% of the other SLE patients. When reactivity to neuroblastoma cell lines only was assessed, 43% of NP-SLE patient sera demonstrated binding activity, versus 14% of sera from the remaining SLE patients. Control subjects' reactivity to neuroblastoma cell lines was positive in 12% of sera. Analysis of serum reactivity using non-neuronal cell lines revealed that neuroblastoma, but not glioblastoma, cell binding was specific. NP-SLE patients with evidence of diffuse symptomatology had a higher mean titer of neuroblastoma cell line binding than those with focal symptomatology. Using a panel of substrates, one can identify a significant proportion of patients who are independently defined as having NP-SLE, who demonstrate specific serum neuronal antibodies.

Clonal origin of human basophil/mast cells from circulating multipotent hemopoietic progenitors

The origin of the human basophil/mast cell lineage from a pluripotent hematopoietic stem cell has been surmised but never demonstrated. By examining individual hemopoietic colonies in methylcellulose under inverted microscopy and using histochemical stains in conjunction with single-colony histamine assays, we have previously identified basophil/mast cell progenitors in human peripheral blood. We now report that a large proportion of normal human peripheral blood mixed granuloerythropoietic (GEMM) colonies contain histamine, in contrast to a significantly lower frequency of histamine positivity among normal neutrophil-macrophage, eosinophil, erythroid, macrophage, or megakaryocyte colonies. Morphological observations confirmed the presence of basophil/mast cells in the majority of GEMM colonies. In our work, the clonal derivation of basophils/mast cells from circulating multipotent (CFU-GEMM) hemopoietic stem cells was formally demonstrated, using combined histamine and G6PD isoenzyme analysis of single colonies grown in methylcellulose from a normal G6PD heterozygote.

Mast cell heterogeneity

Increasing evidence for the existence of inter- and intra-species mast cell heterogeneity has expanded the potential biological role of this cell. Early studies suggesting that mast cells at mucosal sites differ morphologically and histochemically from connective tissue mast cells have been confirmed using isolated intestinal mucosal mast cells in the rat and more recently in man. These studies also established that mucosal mast cells are functionally distinct from connective tissue mast cells. Thus, mucosal and connective tissue mast cells differ in their responsiveness to a variety of mast cell secretagogues and antiallergic agents. Speculation about the therapeutic use of antiallergic drugs in disorders involving intestinal mast cells cannot, therefore, be based on extrapolation from studies of their effects on mast cells from other sites. Regulatory mechanisms for mast cell secretion may also be heterogeneous since mucosal mast cells differ from connective tissue mast cells in their response to a variety of physiologically occurring regulatory peptides. The development of techniques to purify isolated mast cell subpopulations will facilitate future analysis of the biochemical basis of the functional heterogeneity of mast cells.

Platelet activating factor: regulation by mast cells and aspirin

We have investigated some aspects of the regulation of production of rat platelet activating factor (PAF)2 in vitro. Suspensions of unseparated (PLC1), mast cell-depleted (PLC2), or mast cell (MC)-enriched rat peritoneal lavage cells (PLC) were analyzed for PAF content by extraction at alkaline pH. PAF activity extracted from PLC1 varied inversely with viable cell concentration: at 1 X 10(6) cells/ml, 32 +/- 9.3 PAF units, decreasing to 11.2 +/- 9.5 units at 10 X 10(6) cells/ml, and no activity at higher concentrations. Incubation of PLC1 in Tyrode's buffer or acetylsalicylic acid (ASA), but not salicylate, resulted in a time-dependent loss of PAF activity. Mean PAF activity of PLC2 was similar to that in PLC1, while no PAF activity was extractable from MC. Co-incubation with MC extracts inhibited PAF activity of PLC1 extracts in a dose-dependent fashion. Ultracentrifugation of PAF-containing samples led to a loss of all PAF activity in PLC1 extracts, suggesting the association of PAF activity with subcellular components. PAF appears to be derived from a non-MC population of rat PLC, is not extractable from rat PLC in the presence of ASA and is inhibited by MC extracts. These studies suggest that ASA regulates PAF availability unrelated to its effect on cyclooxygenase and that MC membrane products directly inhibit PAF activity from rat PLC.

Association of chronic urticaria and angioedema with thyroid autoimmunity

Seventeen patients, constituting 12.1% of 140 consecutively seen cases of chronic urticaria, demonstrated thyroid autoimmunity with thyroid microsomal antibodies (TMAs) in serum titers greater than or equal to 1:1,600. Eight of these 17 patients had goiter or thyroid dysfunction. In a control group of 477 consecutively seen patients, only 27 (5.6%) had similar TMA titers. Routine and special immunologic test results in this group of 17 patients did not differ from those found in other patients with chronic urticaria and angioedema (CUA), and the only notable clinical feature was that all 17 had angioedema. The age and sex distribution and thyroid features of these 17 patients were similar to those described in autoimmune thyroiditis. Patients (especially women) with CUA should be tested for the presence of TMAs. In this subgroup, CUA may have an autoimmune basis.

Serum lymphocytotoxic antibodies in neuropsychiatric lupus: a serial study

The pathogenesis of neuropsychiatric (NP) SLE remains speculative. A relationship between circulating brain cross-reactive lymphocyte antibodies (LCA) and NP-SLE has been postulated but serial, prospective study of LCA in individual patients with SLE has rarely been performed. In the current study a group of 34 patients with SLE was analyzed using clinical, neurologic, psychiatric, and neuropsychological examinations, together with routine serological tests, to define NP-SLE. Previous history of alloimmunization was also recorded. LCA were measured by a two-stage microcytotoxicity assay against a panel of 25 normal donor B and T cells, at both 40 and 37 degrees C. LCA by this method were found in the serum of 20/34 (58%) SLE, 2/22 (9%) rheumatoid arthritis, and 3/24 (12%) antinuclear-antibody-positive chronic psychiatric patients (P less than 0.01). Analysis of LCA serially in individual SLE patients revealed: (1) No difference in B- or T-cell reactivity at either 4 or 37 degrees C, (2) no significant correlation between previous alloimmunization and the presence of LCA, (3) fluctuations in LCA associated with NP-SLE relapses or remissions, but not with therapy, in 10 patients prospectively studied. A significant positive association was found between the occurrence of single neuropsychiatric events and serial LCA determinations in 180 sera (P less than 0.000001). LCA as measured in this study appear more frequently in SLE than in controls and may indicate active NP-SLE in some patients. Further study of the pathogenic role and diagnostic value of LCA in NP-SLE, including their relationship to subtle neurocognitive changes, is proposed.

Basophil/mast cell precursors in human peripheral blood

Semisolid (methylcellulose) hemopoietic cultures revealed the presence of histamine-containing granulocyte colonies derived from precursors (CFU-C) present in human peripheral blood. Light microscopy and histochemical studies of cells in individual histamine-containing colonies demonstrated homogeneous populations of metachromatic basophil/mast cells (BMC) at various stages of maturation. By inverted microscopy, pure BMC colonies were more often found to have the overall appearance of the previously described "eosinophil" (type II), rather than "neutrophil-macrophage" (type I), colony type. Histamine-positive colonies constituted 58% (50/86) of all (type I and type II) granulocyte colonies in repeated cultures from a patient with systemic mastocytosis (SM), and 19% (13/67) of colonies in cultures from 8 patients with chronic myeloid leukemia (CML); this was in contrast to 8% (12/153) of colonies in cultures from 4 patients with urticaria pigmentosa (UP) and 6 normal controls (p less than 0.0001). Calculated frequency of BMC CFU-C was approximately 1 per 2 X 10(6) in normal and 1 per 2 X 10(5) nucleated cells in SM peripheral blood. Taking colony size into account, histamine content per cell in histamine-positive type II colonies in SM cultures was 1.1 +/- 0.19 pg, compared to 0.29 +/- 0.08 pg in CML and less than or equal to 0.10 in normals and UP. Electron microscopy (EM) of individual colonies revealed electron-dense granules with ultrastructural features of BMC in histamine-positive, but not histamine-negative, colonies. Use of these methods may help to further clarify the nature of BMC precursors and the regulation of their proliferation in bone marrow disorders and allergic states.