Neutropenia in three patients with rheumatic disorders. Suppression of granulopoiesis by control-sensitive thymus-dependent lymphocytes

Agranulocytosis in Sjögren's syndrome: two case reports and analysis of 11 additional reported cases

OBJECTIVES

To report 2 patients who presented with agranulocytosis that was found to be immune-mediated and associated with occult primary Sjögren's syndrome (primary SS) and to identify and study similar cases reported in the literature.

METHODS

Two patients encountered in 2 large medical centers over a period of 5 years were studied in detail. All reported cases of agranulocytosis in primary SS identified through a MEDLINE search were reviewed.

RESULTS

Two patients presented with marked systemic symptoms alone or associated with recurrent infections. Agranulocytosis with either a pattern of maturation arrest or a hypercellular reactive bone marrow was found and was associated with "acute phase" markers, hypergammaglobulinemia, a small paraprotein peak, and high rheumatoid factor titers. A diagnosis of immune-mediated agranulocytosis associated with an occult primary SS was established and was successfully treated with intravenous immunoglobulins or prednisone. Both patients subsequently developed skin vasculitis. This rare association of agranulocytosis and Sjögren's syndrome was identified in 11 other cases and was the presenting manifestation of primary SS in 10 of 13 (77%) patients.

CONCLUSIONS

Agranulocytosis should be recognized as a rare but well-established association of primary SS. Bone marrow neutrophil production may be affected, or neutrophils may be destroyed in the circulation, by both humoral and cellular immune-mediated mechanisms. Agranulocytosis or neutropenia should be added to the varied hematologic manifestations of primary SS and may be its presenting feature and an important clue to diagnosis.

Cell-mediated immune-pancytopenia complicating primary Sjögren's syndrome

A 64-year-old woman with mild bilateral parotid gland swelling and bilateral lower extremity purpura was admitted for evaluation of xerostomia and pancytopenia. The patient had an increased erythrocyte sedimentation rate, pancytopenia, and positive tests for antibodies to nuclear antigen, SS-A, and SS-B. Impaired cell-mediated immunity was also present. Bone marrow aspiration showed a hypoplastic marrow with an increased percentage of lymphocytes. A positive Schirmer's test and keratoconjunctivitis were also noted. A diagnosis of primary Sjögren's syndrome was made by sialography and histological salivary gland findings. Therapy with prednisolone improved the pancytopenia. Addition of the patient's peripheral blood mononuclear cells to cultures of bone marrow mononuclear cells derived from a healthy volunteer dose dependently inhibited colony formation, including mixed hemopoietic colonies. On the other hand, addition of the patient's serum failed to inhibit colony formation by normal bone marrow mononuclear cells. These results suggested that one of the causes of pancytopenia in primary Sjögren's syndrome might be mediated by the inhibition of mononuclear cells to the hemopoietic progenitors.

Felty's and pseudo-Felty's syndromes

Felty's syndrome, consisting of rheumatoid arthritis, leukopenia, and splenomegaly, has been recognized as a distinct clinical entity for more than 60 years. Clinical and laboratory manifestations of the condition are reviewed. The major sources of morbidity and mortality remain recurrent local and systemic infections. Immunogenetic analysis shows a strong association with HLA-DR4, in addition to DQ beta 3b and C4B null allele. Potential mechanisms of neutropenia are contrasted, including impaired granulopoiesis and neutrophil-immune complex interactions. Lithium carbonate and splenectomy may have a role in the treatment of fulminant disease. Maintenance therapy should be directed at control of the underlying inflammatory arthropathy. A syndrome of proliferation of large granular lymphocytes and neutropenia, associated with rheumatoid arthritis in 23% to 39% of cases, has been described recently. Cases of "pseudo-Felty's" syndrome are often confused with traditional Felty's syndrome, which has twice the prevalence. The clinical and laboratory distinctions between these two conditions are elaborated.

Complications of infection and immunologic status after surgery for patients with esophageal cancer

Correlations between defective cell-mediated immunity (CMI) and infections following surgery for esophageal cancer were evaluated. Peripheral lymphocytes, T cells, B cells, PHA transformation, and PPD skin test were measured in 81 patients with esophageal cancer, 58 with gastric cancer, and 50 healthy controls. The depression of CMI was predominant to a similar extent in patients with esophageal cancer and in those with gastric cancer. The average level of PHA transformation immediately before surgery was significantly lower in the esophageal cancer patients with fatal septic complications than in those without such problems. Although preoperative radiation therapy markedly depressed the levels of the four parameters, this association was also noted in 28 patients not given radiation. It thus appears that PHA transformation may be valuable in the prediction of fatal septic complications after major surgery in patients with esophageal cancer.

In vivo inhibition of granulopoiesis in acute inflammation requires T lymphocyte integrity

In previous studies, we have shown that mice undergoing an inflammatory reaction induced by subcutaneous (s.c.) implantation of copper rods elaborate humoral factors that initially enhance, and subsequently inhibit, diffusion chamber (DC) granulopoiesis. In order to quantify the inhibition of DC granulopoiesis after inflammation, one to three copper rods were implanted s.c. either at the same place (1 abscess), or at different sites (multiple abscesses). There was an inverse relationship between the increase in the number of abscesses, and the number of DC granulocytic cells measured in the inhibitory phase. To investigate the role of T lymphocytes in the release of putative inhibitory factor(s) that act on DC cells, cyclosporin A (CyA), a T lymphocyte function inhibitor, was given orally each day (0.75 mg) to mice, starting two days before copper implantation. CyA abrogated the inflammation-related inhibition on DC spleen colony-forming units (CFU-s), granulocyte-macrophage colony-forming units (CFU-gm), and total cell production. To confirm these results, DC were implanted in T cell deficient nude mice where no inhibition of DC cells was observed after inflammation. In conclusion, our data suggest that the in vivo inhibition of granulopoiesis is related to the level of the inflammatory stimulus and requires the functional integrity of T cells.

Effect of corticosteroid treatment on hemopoiesis in vivo and in vitro in a patient with Felty's syndrome

We have studied the CFU-GM and BFU-E in vitro growth in a neutropenic and anemic patient with Felty's syndrome, either before or one and three months after steroid therapy when neutrophils and erythrocytes returned to normal. Both CFU-GM growth and CSA production were found to be low before therapy, and prednisone was shown to raise them to normal levels. The in vitro growth of BFU-E and the production of BPA by T lymphocytes of the patient were significantly lower than normal when studied before therapy. However, the T lymphocytes incubated in vitro with hydrocortisone regained their ability to stimulate the BFU-E growth. After prednisone therapy both BFU-E growth and BPA production by T lymphocytes returned to normal. Possible pathogenetic mechanisms of impaired granulo- and erythropoiesis in Felty's syndrome are discussed. The in vitro study with hydrocortisone can help to identify steroid-sensitive patients.

Reversal of neutropenia with methotrexate treatment in patients with Felty's syndrome. Correlation of response with neutrophil-reactive IgG

We evaluated the clinical and hematologic response to methotrexate (MTX) in 4 women with Felty's syndrome (FS) who had had neutropenia for 1-3 years. Since immune complexes or antineutrophil antibodies are implicated in the pathogenesis of the neutropenia of FS, we also measured both direct and indirect levels of neutrophil-reactive IgG. All 4 patients showed a prompt and dramatic increase in neutrophil counts within 1-2 months of starting MTX therapy. In 3 patients, the symptoms of arthritis also improved; in the fourth patient, arthritis worsened. Recurring infections ceased in 3 patients. Neutrophil-reactive IgG levels, which were elevated in all patients prior to treatment, decreased toward normal while the patients were receiving MTX therapy. We conclude that MTX is effective in treating the neutropenia of FS, in part by lowering neutrophil-reactive IgG.

Role of immunocompetent cells in the regulation of human megakaryocytopoiesis in vitro

T cells and monocytes/macrophages (Mo) have been shown to play important roles in modulating the growth and differentiation of human erythroid and myeloid progenitors and have been implicated in the mechanisms of gamma interferon (gamma-IFN) mediated suppression of normal human marrow erythroid progenitors in vitro. In order to assess the importance of T cells and Mo in the growth of human megakaryocytic progenitors (CFU-Mk) in vitro and to investigate gamma-IFN effect on human megakaryocytopoiesis, normal human marrow (BM) was cultured in plasma clot in the presence and absence T cells, Mo and gamma-IFN under conditions that support the formation of CFU-Mk derived colonies. The removal of T cells from BM (BM-T) caused a significant decrease (71.3 +/- 3.2 colonies observed vs 231.2 +/- 38.5 colonies predicted) in both the number and size of CFU-Mk derived colonies, and no such changes were seen with Mo depletion (BM-Mo); co-culture of autologous T cells with BM depleted of both Mo and T cells (BM-Mo-T) caused a significant increase in CFU-Mk derived colonies and restored colony size. The addition of gamma-IFN (less than 50-10,000 IU/ml) to BM caused a dose dependent inhibition of CFU-Mk (0-90%) as evidenced by decreased colony numbers and reduced colony size. The addition of gamma-IFN (50-10,000 IU/ml) to BM-T caused reduced inhibition of CFU-Mk (0-60%); co-culture of T cells (but not Mo) pre-incubated with gamma-IFN (10,000 IU/ml; 1 hour, 37 C followed by washing X 3) resulted in supression of CFU-Mk (80% inhibition with the addition of 1:4 T cells:marrow cells). The results demonstrate that T cells have the ability to modulate the growth of human CFU-Mk in vitro and may, under appropriate conditions, either promote (normal T cells) or inhibit (gamma-IFN activated T Cells) human megakaryocytopoiesis.

Release of granulocyte-macrophage colony-inhibiting activity by normal human postthymic precursor cells

Seven normal human peripheral blood cell fractions (buffy coat, mononuclear cells, non-T, T, Fc-IgM receptor-depleted T-lymphocyte, Fc-IgG receptor-depleted T-lymphocyte, and autologous rosette-forming T-cell-depleted T-lymphocyte subpopulations) treated with phytohemagglutinin (PHA) were examined for the production of granulocyte-macrophage colony-stimulating activity (CSA). It was found that medium conditioned by a T-lymphocyte subpopulation depleted of autologous rosette-forming T-cells (Tar cells, a postthymic precursor subpopulation that inhibits Ig synthesis) stimulated colony-forming units of granulocyte and macrophages (CFU-GM) to a greater extent than did the other conditioned media (CM) analyzed. Based on this finding, CM from an enriched Tar subpopulation was prepared and thus showed that PHA-treated Tar cells release a factor capable of inhibiting CFU-GM growth. The inhibitory activity of this factor persisted-after heat inactivation, suggesting that cause of the colony-inhibiting activity (CIA) is other than interferon. Further studies revealed that Tar-derived inhibitory factor acts either directly upon CFU-GM or via monocytes/macrophages (M phi/Ma), enhancing CIA, and not the level of CSA production by M phi/Ma. The overall data are interpreted as demonstrating the presence of CIA in a specific T-lymphocyte subpopulation that may represent a new relationship between lymphocytic and myelocytic systems in the human.

A burn induced Ly-2 suppressor T cell lowers resistance to bacterial infection

Suppressor T cell activity after major burn injury in a murine model has been well characterized. Suppressor cells have also been demonstrated in patients after major burn, and suppressor cell activity has been temporally correlated with septic episodes. A splenic Ly-2 T suppressor effector (Tse) cell appearing 7 days after a 30% full thickness burn has been identified in a murine model. A rat monoclonal antibody (14-8c3-12) directed against a factor produced by the Tse cell (Tsef) can enhance depressed in vitro mixed lymphocyte reaction (MLR) responses of Day 7 burn spleen cells without enhancing control spleen cell activity. Additionally, 14-8c3-12 can block the suppressive effect of these burn T cells on normal T cells. A cecal ligation and puncture (CLP) model using a 25-gauge needle (LD15) was used to assess the contribution of burn T cells to post-CLP mortality. Normal spleen cells injected into syngeneic recipients followed by CLP did not affect mortality (13%). Burn spleen cells injected into normal recipients enhanced mortality sixfold (90%) after CLP. The effect could be reversed by removing Ly-2 T cells (30% mortality) but not Ly-1 T cells (100% mortality) prior to cell transfer. Simultaneous injection of 14-8c3-12 antibody with burn T cells reduced mortality after CLP significantly (20%). Injection of 14-8c3-12 did not improve survival after CLP in control animals not injected with burn T cells (20%). Ly-2 T suppressor effector cells found in the spleens of mice 7 days postburn enhance the lethality of a purely bacterial septic challenge. A monoclonal antibody to the Tsef can reverse this effect in vivo.

Current considerations of the etiology of aplastic anemia

Aplastic anemia is a disorder characterized by marrow aplasia and pancytopenia. The pathogenetic mechanisms that lead to bone marrow aplasia have been intensively studied. Data obtained from these studies suggest that aplastic anemia is a heterogeneous disorder with regards to pathogenesis. Bone marrow aplasia may result from a number of abnormalities including qualitative or quantitative abnormalities of hematopoietic stem cells, abnormal interaction between bone marrow accessory cells (lymphocytes and macrophages) and hematopoietic stem cells, cytotoxic humoral inhibitors of hematopoiesis, and abnormalities of the bone marrow microenvironment. A number of new therapeutic options have improved the survival of patients with aplastic anemia. Allogeneic bone marrow transplantation has actually resulted in the cure of patients. Unfortunately, only a minority of patients have a suitable bone marrow donor and alternate modes of therapy have been sought. Encouraging results have been reported from several centers concerning the use of antilymphocyte serum in patients with aplastic anemia. Certainty of the ultimate long-term benefit of this type of immunosuppressive therapy is not possible until careful, randomized, prospective studies of its use are completed.

Pathology-important advances in clinical medicine: assessing fetal lung maturity

The Scientific Board of the California Medical Association presents the following inventory of items of progress in pathology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and important clinical significance. The items are presented in simple epitome and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, research workers or scholars to stay abreast of these items of progress in pathology that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another.The items of progress listed below were selected by the Advisory Panel to the Section on Pathology of the California Medical Association and the summaries were prepared under its direction.

T-lymphocyte--mediated granulopoietic failure. In vitro identification of prednisone-responsive patients

To identify patients with T-lymphocyte--mediated granulopoietic failure, we compared clonal growth of unfractionated bone-marrow cells with that of autologous marrow cells from which T lymphocytes had been removed, in a group of 234 patients. We also attempted to identify prednisone-responsive patients by culturing both unfractionated and T-depleted cells with and without glucocorticoids in vitro. Ninety-three patients were treated with prednisone for two to four weeks. Neutropenia resolved in 24 of 25 patients whose colony growth was enhanced by glucocorticoids in vitro, but in none of 68 whose cultures showed no response (P = 10(-10). Hemopoietic inhibitory T cells were found in 21 of the 24 prednisone-responsive patients. When these 21 patients were restudied during steroid treatment, the hemopoietic inhibitory cells were undetectable in steroid-responsive patients but were present in steroid-resistant patients. T lymphocytes can mediate granulopoietic failure in a variety of conditions, and in vitro studies identify most of the patients with these conditions. Hemopoietic inhibitory T cells are often steroid-sensitive, and in vitro study accurately predicts responses to steroid therapy.

Response of agranulocytosis to prolonged antithymocyte globulin therapy

A girl with a history of autoimmune disease developed life-threatening agranulocytosis. A bone marrow biopsy demonstrated selective granulocytic hypoplasia. No antineutrophil antibodies were found. In vitro bone marrow culture of granulocytic progenitor cells suggested T cell-mediated inhibition of colony formation, which was reduced by in vitro treatment of marrow cells with either hydrocortisone or an antibody directed against T-lymphocytes and complement. The patient responded to treatment with antithymocyte globulin after administration of corticosteroids and other immunosuppressants failed to increase her neutrophil count significantly. Attempts to stop ATG treatment resulted in precipitous drops in her neutrophil counts, which reversed with readministration of ATG. She then received weekly ATG infusions for over 24 months until she was able to maintain a normal neutrophil count. A trial of ATG therapy may be indicated in severe neutropenia when in vitro culture results indicate a possible autoimmune basis.

Heterogeneity of bone marrow-directed immune mechanisms in the pathogenesis of neutropenia of Felty's syndrome

Twenty-seven patients with Felty's syndrome were studied by the colony forming unit in culture (CFU-C) assay for possible immune mechanisms within the bone marrow compartment that could contribute to the neutropenia. Depletion of bone marrow suppressor T cells resulted in normal CFU-C numbers in 7 patients. In 5 patients serum antiprecursor cell activity was detected. Blood monocytes failed to generate colony stimulating factor in 5 patients. Bone marrow-directed immune mechanisms are heterogeneous and could play a role in the pathogenesis of neutropenia in some patients with Felty's syndrome.

Antibodies reactive with surface membranes of cellular elements in the blood

Autoreactive antibodies or immune complexes may accelerate clearance of mature erythrocytes, leukocytes, and platelets from the circulation in patients with rheumatologic and immunologic disorders. The most compelling evidence for immune injury to hematopoietic cells exists in patients with systemic lupus erythematosus and patients with Felty's syndrome and its variants. These disorders may also cause tissue inflammation, which in turn commonly results in underproduction of erythrocytes and development of thrombocytosis. However, recent evidence indicates that underproduction of hematopoietic cells may also result from immune injury to cellular elements in the bone marrow. In many laboratories, sensitive techniques are now clinically available for the detection of cell-associated immunoglobulin and complement. These assays have helped confirm the role of antibody in the pathogenesis of autoimmune hemolytic anemia and idiopathic thrombocytopenic purpura. However, recent data indicate that there is probably a continuum between the amount of immunoglobulin and complement found on normal cells and that found in a variety of disease states. In several of these disorders, additional evidence will be required to establish that the increase in cell-bound immunoglobulin leads to a decrease in the life-span of the cell. In order to provide significant help to the clinician managing an individual patient, these serologic tests must be capable of identifying the portion of the cell-associated protein actually involved in the destructive process. The availability of monoclonal reagents capable of identifying restricted regions on cell-bound immunoglobulin may help identify molecules bound specifically as antibody and may help identify the antigens involved in autoimmune disorders.

Granulopoiesis in systemic lupus erythematosus

The pathogenesis of granulopoietic failure in systemic lupus erythematosus (SLE) was studied. In 16 Japanese women with SLE, a decreased number of granulocyte/monocyte progenitor cells (CFU-C) in the bone marrow was demonstrated, and the number of CFU-C correlated significantly with the peripheral blood granulocyte/monocyte count. The peripheral and bone marrow T lymphocytes suppressed the colony formation of autologous or allogeneic bone marrow CFU-C. These findings suggest that the decreased marrow CFU-C may be due to suppression by T lymphocytes, an event that may play an important role in the pathogenesis of granulopoietic failure in SLE.

Cell mediated inhibition of erythropoiesis and megaloblastic anemia in T-cell chronic lymphocytic leukemia

A patient with T-cell chronic lymphocytic leukemia presented with severe megaloblastic anemia with normal serum folic acid and cobalamin concentrations. BFU-E could not be cultured from the patient's peripheral blood unless T-lymphocytes were removed by E-rosette formation. Inhibitory activity by the patient's T-cells was restricted to autologous BFU-E. After cyclic chemotherapy the anemia and megaloblastic changes resolved, peripheral blood BFU-E could be cultured from unfractionated peripheral blood and the T-cell inhibitory activity could no longer be demonstrated. The anemia in this patient is probably due to the neoplastic expansion of a suppressor T-lymphocyte population.

Dexamethasone enhances 'CSA' release and depresses 'BPA' release

Dexamethasone 10(-7) M enhanced the release of granulocyte-macrophage colony stimulating activity (GM-CSA) by peripheral blood cells from 15 normals. In 16 patients with hypoplastic marrow failure this effect was more prominent, the release of GM-CSA being increased up to 10-fold by dexamethasone. Dose-response curves of patient cell supernatants indicate that dexamethasone acts by abrogation of an inhibitor on CSA-production. Dexamethasone decreased the release of burst promoting activity (BPA) in all normals and most patients. We conclude that the interaction of glucocorticoid hormones with lymphocyte function results in positive and negative effects on haemopoiesis in vitro. Preliminary experiments in one patient suggest that the steroid effect in vivo correlates with GM-CSA enhancement in vitro.

Long-term outcome in Felty's syndrome

Felty's syndrome has again been shown to be a severe form of systemic rheumatoid disease characterised by severe joint involvement, many extra-articular features, and a high incidence of infection. In addition we have shown that splenectomy was not protective for infections and in fact may on occasion contributed to infection. Furthermore, although most patients had an increase in white blood cell count after splenectomy, 50% of patients without splenectomy showed a similar increase in white blood cell counts at follow-up. Mortality in Felty's syndrome was high, with infection being the main cause of death.

Studies of human natural killer cells. III. Neutropenia associated with unusual characteristics of antibody-dependent and natural killer cell-mediated cytotoxicity

A 52-year-old Caucasian man with chronic neutropenia and recurrent infections was found to have an increased proportion of peripheral T lymphocytes having Fc receptors for IgG (T gamma ). Although levels of antibody-dependent cell-mediated cytotoxicity (ADCC) and "natural" killing (NK) by unfractionated lymphocytes were similar to those of a control donor, the frequency of KN cells was markedly increased. Removal of E rosette-forming cells eliminated both NK and ADCC by the patient's peripheral blood, in marked contrast to the enhanced cytotoxicity seen with control lymphocytes. Both normal and patient ADCC and NK functions were removed by depletion of Fc receptor-bearing cells. These depletion experiments proved that all of the patient's killer cells were E rosette-forming T gamma cells, in contrast to the heterogeneous pattern of null gamma and T gamma killer cells seen in the blood of normal donors. The homogeneity of the T gamma proliferation suggested that ADCC and NK were mediated by the same cell type, albeit acting by different mechanisms. The addition of the patient's serum and lymphocytes to chromium-labelled normal granulocytes caused a low but significant level of cytotoxicity, indicating that the patient's neutropenia may have been caused by a similar mechanism in vivo. There was no evidence of complement-dependent serum antibody-mediated neutrophil lysis, but one serum sample taken over the course of the patient's disease agglutinated granulocytes from four of five donors tested.

The mechanism of lithium carbonate-induced augmentation of colony-stimulating activity elaboration in man

Lithium carbonate (Li) has been reported to elevate granulocyte counts in patients with certain neutropenic disorders and to improve chemotherapy-induced granulocytopenia. To investigate the mechanisms involved in the increase in myelopoiesis, the effect of Li on monocytemacrophage (M phi)- and T-lymphocyte (TL)-derived colony-stimulating activity (CSA) were studied in vitro. Li induced a dose-related increase in both M phi- and TL-derived CSA over that in non-Li-stimulated cell populations. However, the increase was significant (p less than 0.007) only at a higher concentration of Li (2 mEq/l). The results of co-incubating TL with M phi with or without Li indicated that Li significantly enhanced synergistic CSA production by the two cell populations (p less than 0.02). We further demonstrated the presence of a larger proportion of M phi with TL rosettes in the presence of Li (62%) than in its absence (21%). Further experiments with concanavalin A (Con-A)-inducible suppressor TL suggested that Li effectively blocks the suppressor TL-mediated suppression of CSA. These data suggest that Li enhances M phi and TL interaction which results in an augmented CSA elaboration. Further, Li would be more effective in those neutropenic disorders associated with enhanced suppressor TL activity. For an optimal effect, however, Li would require appropriately functioning M phi and non-suppressor subsets of TL and an intact stem cell pool.

T lymphocytes involved in inhibition of granulopoiesis in two neutropenic patients are of the cytotoxic/suppressor (T3+T8+) subset

T lymphocyte-mediated bone marrow failure is a recently recognized clinical disorder, but the T lymphocyte subsets responsible for mediating the inhibitory effect have not been identified. We obtained T lymphocytes from the bone marrow of two patients with T lymphocyte-mediated granulopoietic failure, exposed them to monoclonal antibodies (OKT3, OKT4, and OKT8) in cytotoxicity assays, then recombined the treated T cells with autologous T-depleted marrow cells in clonal assays for granulocyte/macrophage progenitors (CFU-GM). Treatment of T cells with OKT3 and OKT8 abrogated their granulopoietic inhibitory effect but treatment with OKT4 did not. Therefore, in these two patients, the lymphocytes that played a role in the inhibition of granulopoiesis were of the cytotoxic/suppressor subset.

Interaction of lactoferrin, monocytes, and T lymphocyte subsets in the regulation of steady-state granulopoiesis in vitro

Colony-stimulating activities (CSA) are potent granulopoietic stimulators in vitro. Using clonogenic assay techniques, we analyzed the degree to which mononuclear phagocytes and T lymphocytes cooperate in the positive (production/release of CSA) and feedback (inhibition of CSA production/release) regulation of granulopoiesis. We measured the effect of lactoferrin (a putative feedback regulator of CSA production) on CSA provision in three separate assay systems wherein granulocyte colony growth of marrow cells from 22 normal volunteers was stimulated by (a) endogenous CSA-producing cells in the marrow cells suspension, (b) autologous peripheral blood leukocytes in feeder layers, and (c) medium conditioned by peripheral blood leukocytes. The CSA-producing cell populations in each assay were varied by using cell separation techniques and exposure of isolated T lymphocytes to methylprednisolone or to monoclonal antibodies to surface antigens and complement. We noted that net CSA production increased more than twofold when a small number of unstimulated T lymphocytes were added to monocyte cultures. Lactoferrin's inhibitory effect was also T lymphocyte dependent. The T lymphocytes that interact with monocytes and lactoferrin to inhibit CSA production are similar to those that augment CSA production because their activities are neither genetically restricted not glucocorticoid sensitive, and both populations express HLA-DR (Ia-like) and T3 antigens but not T4 or T8 antigens. These findings are consistent with results of our studies on the mechanism of lactoferrin's inhibitory effect with indicate that mononuclear phagocytes produce both CSA and soluble factors that stimulate T lymphocytes to produce CSA, and that lactoferrin does not suppress monocyte CSA production, but does completely suppress production or release by monocytes of those factors that stimulate T lymphocytes to produce CSA. We conclude that mononuclear phagocytes and a subset of T lymphocytes exhibit important complex interactions in the regulation of granulopoiesis.

Immune Mediated Neutropenia in Man and Animals: A Review

Immune mediated neutropenia has been reported in human medical literature with increasing frequency over the past 30 years. A wide variety of causes are known and numerous techniques have been developed to test for the presence of antineutrophil antibody. This paper reviews literature pertaining to the pathogenesis, detection and experimental production of immune mediated neutropenia in man and animals.

Granulocytopenia with marked lymphocytosis manifesting Sjogren syndrome

Sjogren syndrome is a multi-system disease leading to diverse organ involvement during its course [1, 2]. Hematologic abnormalities described in Sjogren syndrome include anemia, mild leukopenia [3, 4], eosinophilia, elevated erythrocyte sedimentation rate, hypergammaglobulinemia, mixed cryoglobulinemia, and a variety of autoantibodies [5]. Marked lymphocytosis with granulocytopenia is distinctly unusual and has not been previously reported. We report a case of Sjogren syndrome who presented with constellation of the latter problems without prominent sicca manifestations.

Autoimmune pancytopenia. Lymphocyte inhibition of autologous but not allogenic bone marrow growth in vitro

A patient with autoimmune renal failure, cavitary lung lesions and arthritis experienced pancytopenia while prednisone therapy was being tapered. Utilizing semisolid culture techniques, a population of nonadherent peripheral blood mononuclear cells was demonstrated, which inhibited autologous but not allogeneic bone marrow erythroid colony-forming units (CFU-E) and myeloid colony-forming units (CFU-c) in vitro. No inhibition of CFU-E or CFU-c colony formation was seen when patient's serum or immunoglobulin G (IgG) was added to cultures. Reinstitution of prednisone therapy resulted in normalization of peripheral blood counts, which was accompanied by the loss of the hemopoietic inhibitor cell activity in the patient's peripheral blood. These results demonstrate the need for testing autologous marrow samples when looking for possible immune-mediated inhibition of hematopoiesis.