An immunohistochemical study of topical cyclosporine in vernal keratoconjunctivitis

PURPOSE

To determine the immunomodulating effects of topical cyclosporine on the immune cells in the conjunctival biopsy specimens obtained from patients with active vernal keratoconjunctivitis.

METHODS

We studied six patients who had severe active vernal keratoconjunctivitis. Each patient was given topical cyclosporine 2% eyedrops four times daily. A 2 x 2-mm limbal conjunctival biopsy specimen was obtained from each patient before and three weeks after treatment. Using a panel of monoclonal and polyclonal antibodies and immunohistochemical techniques, we analyzed the conjunctival immune cells before and after cyclosporine treatment.

RESULTS

Three weeks after topical cyclosporine treatment, there was marked clinical improvement and a statistically significant reduction in the number of epithelial and stromal class II MHC+ cells, UCHL1+ T cells, and stromal IgA+ and IgG+ plasma cells. The mean number of cells before and after therapy, respectively, were: class II MHC+ (epithelium), 31.5 +/- 13.1 and 8.3 +/- 5.6 (P = .031); class II MHC+ (stroma), 77.0 +/- 28.7 and 24.7 +/- 17.5 (P = .031); UCHL1+ T cells (epithelium), 24.5 +/- 14.1 and 4.2 +/- 2.9 (P = .031); UCHL1+ T cells (stroma), 78.7 +/- 31.1 and 44.5 +/- 27.5 (P = .031); IgA+ plasma cells, 66.7 +/- 32.1 and 22.2 +/- 7.8 (P = .031); and IgG+ plasma cells, 37.3 +/- 30.0 and 9.0 +/- 6.4 (P = .031). There was a statistically insignificant decrease in the epithelial class II MHC+ dendritic Langerhans cells, epithelial and stromal KP1+ macrophages, stromal OPD4+ helper/inducer T cells, and stromal L26+ B cells. The numbers of IgE+ plasma cells and mast cells were unaltered.

CONCLUSION

The clinical improvement in vernal keratoconjunctivitis after topical cyclosporine therapy may result from its immunomodulating effect on the components of cell-mediated and humoral immune responses. In contrast, the drug has no immunomodulatory effect on mast cells and IgE-mediated allergic response.

Plasmacytoma development in mice injected with silicone gels

Silicone gels derived from commercially obtained implants induce plasmacytomas in 60-70% of highly susceptible BALB/cAn.DBA/2-Idh1-Pep3 congenic mice. In contrast, dimethylpolysiloxane (DMPS) silicone oils with viscosities of 5, 1000 and 12,500 cs fail to elicit these tumors. 1000 cs vinylmethylpolysiloxane is also inactive. Silicone gels, in contrast to the oils, induce a highly inflammatory silicone granuloma. Silicone gels contain chemical components not found in the oils. The chemical component responsible for inducing the permissive environment for plasmacytoma formation has not yet been identified. Silicone gels are well tolerated for long periods of time in mice without adverse effects other than plasmacytoma formation. The response to different gel preparations varies; some are associated with relatively rapid formation of plasmacytomas resembling that seen with pristane, while in others the plasmacytoma formation is extended nearly over a two year period.

Laminin and fibronectin promote the chemotaxis of human malignant plasma cell lines

We examined chemotaxis of human plasma cells (PCs) in response to extracellular matrix proteins (ECMs) in the human PC cell lines FR4ds and OPM-1ds. The FR4ds cells expressed beta 1+, beta 3-, alpha 2-, alpha 3-, alpha 4+, alpha 5+, alpha 6+, and alpha v+ integrins, whereas the OPM-1ds cells expressed beta 1+, beta 3-, alpha 2-, alpha 3+, alpha 4+, alpha 5-, alpha 6+, and alpha v+. Fibronectin (FN) and laminin (LN) promoted the chemotaxis of the PCs. An inhibitory assay with anti-integrin monoclonal antibodies (MoAbs) showed that anti-alpha 4 MoAb partially inhibited the chemotaxis of FR4ds and completely inhibited the chemotaxis of OPM-1ds. Anti-alpha 5 MoAb alone had no effect on either of these two lines. Nevertheless, anti-alpha 5 MoAb completely inhibited chemotaxis when it was added with anti-alpha 4 in FR4ds, demonstrating a novel complementary role of VLA-5 toward VLA-4 in the chemotaxis induced by FN. LN facilitated chemotaxis both in OPM-1ds expressing alpha 3 and alpha 6 integrins and in FR4ds expressing alpha 6 integrin alone. Anti-alpha 6 MoAb completely inhibited FR4ds chemotaxis, whereas anti-alpha 3 and -alpha 6 MoAb had synergistic inhibitory effects on the chemotaxis of OPM-1ds. These results indicated that the distribution of PCs in human tissue are determined by at least two factors: the concentration of the ECM proteins FN and LN and the expression of integrins.

Interleukin-10 is a proliferation factor but not a differentiation factor for human myeloma cells

Because interleukin-10 (IL-10) is a potent differentiation factor of human B cells into mature plasma cells, we investigated its effect on human malignant plasma cells. IL-10 did not induce any differentiation and increase in Ig synthesis in four human IL-6-dependent malignant plasma cell lines. However, it stimulated the proliferation of two of four cytokine-dependent cell lines in the absence of IL-6 and IL-10-dependent myeloma cell lines have been obtained. The myeloma cell growth activity of IL-10 was unaffected by anti-IL-6 and anti-IL-6R antibodies. Similarly, IL-10 stimulated (P = .001) the proliferation of freshly-explanted myeloma cells in IL-6-deprived cultures of tumor samples from patients with active multiple myeloma (MM) and produced twice as many myeloma cells in these cultures. Again, this cytokine was unable to induce further differentiation (assessed by rate of Ig production) of fresh myeloma cells. A very sensitive enzyme-linked immunosorbent assay (ELISA; 1 pg/mL) only rarely detected IL-10 in the sera of MM patients (3 of 89). On the contrary, serum IL-10 was detected in 60% of patients with plasma cell leukemia (12 of 20). These data show that IL-10 is an IL-6-unrelated growth factor for malignant plasmablastic cells. This cytokine could be involved in the late phase of MM in vivo.

Differentiation of early plasma cells on bone marrow stromal cells requires interleukin-6 for escaping from apoptosis

The bone marrow (BM) is well known to be the major site of Ig production in secondary immune responses; thus, the microenvironment of BM is considered to be essential for final differentiation of plasma cells. We identified in the peripheral blood (PB) early plasma cells (CD38++CD19+VLA-5-) committed to entering the BM. The sorted early plasma cells rapidly entered apoptosis in vitro, but these cells could survive and further differentiate into mature plasma cells (CD38 CD19+) just as BM plasma cells in the presence of a BM-derived stromal cell line (KM-102). Culture supernatants of KM-102 cell lines could also support survival of these cells, and antibody to interleukin-6 (IL-6) completely blocked the effect of these supernatants. Furthermore, recombinant IL-6, but not IL-1 or IL-3, could support their survival and their differentiation into mature plasma cells (CD38 CD19+VLA-5+) with expression of VLA-5 mRNA. Therefore, here is direct evidence that early plasma cells found in the PB differentiated into mature plasma cells with stromal cell-derived IL-6 in vitro; thus, BM stromal cells control the final checkpoint of plasma cell differentiation with secretion of IL-6 in the BM.

Melanin-containing hydrogel intraocular lenses: a histopathological study in animal eyes

Poly(2-hydroxyethyl methacrylate) hydrogel intraocular lenses, containing adrenochrome-melanin, were manufactured and implanted in animal eyes in order to assess the effect of melanin upon (a) biocompatibility of implants with the eye tissues, and (b) fibrous proliferation of lens epithelium responsible for the opacification of the posterior capsular membrane. An equal number of control lenses were also implanted. The animals were followed up for durations up to two years, and a detailed histopathological examination of the eyes was performed subsequent to their enucleation. The postoperative complications were minor and probably caused by surgical trauma. The study failed to give any indication of the postulated antiproliferative activity of adrenochrome-melanin since minimal capsular opacification occurred in the operated eyes, regardless of the presence of melanin.

GM1, a ganglioside that specifically enhances immunoglobulin production and proliferation in human plasma cells

The effects of gangliosides on human plasma cell responses were studied. Among the various gangliosides tested, only GM1 enhanced immunoglobulin (Ig) production and proliferation in the human plasma cell lines, IM-9 and AF-10, while other gangliosides (GM2, GM3, GD1a, GD1b, GD3, GT1b, and GQ1b) had no effect. Among the various cytokines tested, including interleukin (IL)-1 beta, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12, IL-13, interferon (IFN)-alpha and IFN-gamma, only IL-6 enhanced Ig production and proliferation in IM-9 and AF-10 cells. However, the enhancement of plasma cell responses by GM1 was specific and was not mediated by IL-6, since GM1 activity was blocked by anti-GM1 monoclonal antibody (mAb), but not by control IgM, anti-IL-6 Ab or the anti-IL-6 receptor mAb, PM1. Conversely, the enhancement by IL-6 was blocked by anti-IL-6 Ab and PM1, but not by anti-GM1 mAb. GM1, but not other gangliosides, also enhanced Ig production and proliferation in freshly separated plasma cells from patients with plasma cell leukemia and in plasma cells generated in vitro. These actions of GM1 were specifically blocked by anti-GM1 mAb, but not by anti-IL-6 Ab or PM1. These results indicate that GM1 may be an important regulator of plasma cell responses.

Differential effect of growth hormone and insulin-like growth factor-I, insulin-like growth factor-II, and insulin on Ig production and growth in human plasma cells

The effect of human growth hormone (GH) and insulin-like growth factor-I (IGF-I), IGF-II, and insulin on human plasma cell responses was studied. GH enhanced Ig production and thymidine uptake in the human plasma cell lines, IM-9 and AF-10. IGF-I, but not IGF-II or insulin, also enhanced Ig production and proliferation in them. However, enhancement by GH was not mediated by IGF-I, because enhancement was blocked by anti-GH antibody (Ab), but not by Ab to IGF-I or IGF-I receptor. Conversely, the enhancement by IGF-I was blocked by either Ab to IGF-I or IGF-I receptor, but not by anti-GH Ab. GH and IGF-I also enhanced production of IgG1, IgG2, IgG3, IgG4, IgA1, IgA2, and IgM and thymidine uptake in PCA-1+ plasma cells generated in vitro. Again, enhancement by GH was specifically blocked by anti-GH Ab, whereas enhancement by IGF-I was specifically blocked by either Ab to IGF-I or IGF-I receptor. These results indicate that GH and IGF-I may play important roles in plasma cell responses.

The effect of alloxan diabetes and local irritating factors on gingival lymphocytes and plasma cells and serum IgG, IgM and IgA levels

A histologic study was conducted in 5 diabetic and 5 non-diabetic albino rabbits to determine the effect of experimentally induced diabetes upon the number of gingival plasma cells and lymphocytes in the absence and presence of local factors, and IgG, IgM and IgA levels of the four groups were compared with each other. In conclusion, local factors were primarily responsible for the increase of the gingival plasma cells and lymphocytes. There was no statistically significant difference between the diabetic and non-diabetic group in the absence of local factors. Also, there was no marked difference between the serum IgG, IgA and IgM levels of all groups.

Regulation of IL-6 receptor and gp130 expression on human cell lines of lymphoid and myeloid origin

The expression of 80 kDa interleukin-6 receptor (IL-6R) and the associated molecule gp130 has been studied on human cell lines by FACS- and Northern blot analysis. The effects of dexamethasone, dibutyric-(DB)-cAMP and phorbol-12-myristate-13-acetate (TPA) have been studied on plasmacytoma cell line U266, B cell line BMNH and monocytoid cell line U937. Our data show a definite downregulation of IL-6R and gp130 expression by TPA in U266 and BMNH at both mRNA and cell surface protein levels. In U937 TPA inhibits only the IL-6R expression, without affecting that of gp130. DB-cAMP decreases the expression of both proteins in U937, slightly inhibits the IL-6R expression in U266, but is uneffective in BMNH. Dexamethasone induces considerable upregulation of gp130 only in U266. Our findings suggest separate regulation of IL-6R and gp130 on U266, BMNH and U937 cell lines.

Eosinophil cationic protein inhibits immunoglobulin production and proliferation in vitro in human plasma cells

The effect of eosinophil cationic protein (ECP) on immunoglobulin (Ig) production by and proliferation of human plasma cells was studied. ECP inhibited Ig production by and proliferation of the human plasma cell lines, IM-9 and AF-10, in a dose-dependent fashion. As little as 0.05 ng/ml ECP was found to be inhibitory, and the maximal inhibition was achieved at doses of 0.1-0.5 ng/ml ECP. This inhibition was not due to cytotoxicity, since viability was always greater than 98%. Kinetic experiments demonstrated that inhibition was observable after 24 hr of culture with ECP and that the inhibitory effect of ECP was reversible. The inhibitory effect of ECP could be blocked by anti-ECP serum, but not by control serum. Of the various cytokines tested, including interleukin (IL)-1 beta, IL-2, IL-3, IL-4, IL-5, IL-6, interferon (IFN)-alpha, IFN-gamma, granulocyte-macrophage colony-stimulating factor (GM-CSF) and erythropoietin (Epo), IL-6 reversed the inhibition, while other cytokines failed to do so. ECP also inhibited Ig (IgG1, IgG2, IgG3, IgG4, IgM, and IgA) production by and proliferation of PCA-1+ plasma cells generated in vitro with a similar dose-response pattern. This inhibition also was blocked by anti-ECP serum but not by control serum, and was restored by IL-6. These results suggest that ECP may interact with IL-6 in controlling plasma cell responses.

Pathological changes in bovine mammary glands following intramammary infusion of recombinant interleukin-2

Eighteen lactating dairy cows were used to evaluate the physiological response of mammary glands to increasing doses of recombinant bovine interleukin-2. Right front and rear quarters were intramammarily infused with five different doses (.1 to 100 micrograms per quarter) of interleukin-2 as either a single or multiple treatment. Left front and rear quarters were intramammarily infused with a saline placebo and served as within-animal controls. Milk secretion samples for compositional analysis were collected from each quarter prior to infusion and at 12, 24, 36, and 48 h following infusion. Animals were slaughtered by exsanguination immediately following the 48-h sampling period, and mammary gland tissue was obtained for morphometric analysis. No changes in milk composition were observed between control quarters and those infused with up to 10 micrograms of interleukin-2 per quarter, administered as either a single or multiple treatment. Quarters infused with a single 100-micrograms dose of interleukin-2 or three consecutive doses of 25 and 100 micrograms of interleukin-2 had significantly lower lactose concentrations; there was a concomitant increase in bovine serum albumin, pH, and SCC compared with preinfusion concentrations or with control quarters. Morphometric analysis of tissue demonstrated an increase in stroma, a decrease in lumenal area, and a marked increase in the number of infiltrating leukocytes in those quarters infused with the higher doses of interleukin-2. Results suggest that interleukin-2 can be intrammammarily infused at doses as high as 10 micrograms per quarter without adversely affecting milk quality or normal mammary gland function.

A comparison of the decarbamoylation rates of physostigmine-inhibited plasma and red cell cholinesterases of man with other species

Plasma and red cells from a variety of animal species were used to demonstrate that there is a relationship between the decarbamoylation rates of physostigmine-inhibited plasma and red cell cholinesterases in vitro and the effectiveness of carbamate pretreatment against nerve agent poisoning reported in the literature. Decarbamoylation rates were faster in the non-human primates than in the guinea-pig, and carbamate pretreatment is more effective in these species than in the guinea-pig. The data for the decarbamoylation rates of physostigmine-inhibited enzymes suggests that the non-human primates are the best animal model for extrapolation of protection studies from animal species to man. Control values for red cell acetylcholinesterase (AChE) activity (mumol/min/mL blood) using acetylthiocholine (1 mM) were higher in the human (4.98) and the rhesus monkey (4.14) than in the marmoset (0.84) and the guinea-pig (0.83). Plasma cholinesterase (ChE) activity (mumol/min/mL plasma) using butyrylthiocholine (10 mM) was highest in the rhesus monkey (9.29), intermediate in human (5.10) and guinea-pig (6.06), and lowest in the marmoset (4.07). There was a species difference in the relative activity of AChE: ChE in blood, human (65:35), rhesus monkey (45:55), marmoset (30:70) and guinea-pig (20:80). The rate of recovery of red cell AChE and plasma ChE activities, following incubation of whole blood with physostigmine (1 x 10(-7) M), was in the order human greater than rhesus monkey greater than marmoset greater than guinea-pig. During the incubation of red cells with physostigmine there was little recovery of AChE activity for 3-4 hr in any species. During the incubation of plasma with physostigmine there was complete recovery of ChE activity by 2-3 hr in the human and rhesus monkey and a significant recovery by 3 hr in the marmoset and guinea-pig. This suggests that a component of plasma, possibly ChE, was responsible for the degradation of physostigmine, presumably by hydrolysis. There was a marked species difference in the decarbamoylation rates of physostigmine-inhibited enzyme. In the red cell the t1/2 values (min) were 14.8 (human), 21.2 (rhesus monkey), 17.9 (marmoset) and 31.9 (guinea-pig). In the plasma the t1/2 values (min) were 11.2 (human), 32.9 (rhesus monkey), 44.1 (marmoset) and 52.4 (guinea-pig).

Nerve growth factor inhibits immunoglobulin production by but not proliferation of human plasma cell lines

The effects of nerve growth factor (NGF) on human plasma cells were studied. NGF inhibited immunoglobulin (Ig) production but not thymidine uptake by human plasma cell lines IM-9 and AF-10 in a dose-dependent fashion. This NGF-induced inhibition of Ig production was specific, since inhibition was blocked by anti-NGF serum but not by control serum. Interleukin (IL)-6 did not affect Ig production by IM-9 and AF-10; however, IL-6 restored NGF-induced inhibition of Ig production. NGF also inhibited Ig production (IgG, IgM, and IgA) without affecting thymidine uptake by PCA-1+ plasma cells generated in vitro. This inhibition was also blocked by anti-NGF serum but not by control serum and was restored by IL-6. These results suggest that NGF may interact with IL-6 in control of Ig production by plasma cells.

Erythropoietin enhances immunoglobulin production and proliferation by human plasma cells in a serum-free medium

The effect of recombinant human erythropoietin (Epo) on plasma cells was studied in a serum-free medium, COSMEDIUM-001 (Cosmedium). Epo enhanced both Ig production and thymidine uptake by human plasma cell lines, AF-10 and IM-9. Interleukin-6 (IL-6) enhanced both Ig production and thymidine uptake by AF-10 and IM-9, while other cytokines, including IL-1 beta, IL-2, IL-3, IL-4, IL-5, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-alpha (IFN-alpha) or IFN-gamma, failed to do so. However, the Epo effect was specific since Epo-induced enhancement of Ig production and thymidine uptake was blocked by the anti-Epo antibody but not by the anti-IL-6 antibody or the control antibody. Conversely, IL-6-induced enhancement was blocked by the anti-IL-6 antibody but not by the anti-Epo antibody. Epo also enhanced Ig production (IgG, IgM, and IgA) and thymidine uptake by PCA-1+ plasma cells generated in vitro. This enhancement was also blocked by the anti-Epo antibody but not by the anti-IL-6 antibody. Taken together, these results suggest that Epo enhances plasma cell responses by a different mechanism than does IL-6.

One explanation of the asthma paradox: inhibition of natural anti-inflammatory mechanism by beta 2-agonists

Our understanding of the mechanisms contributing to the pathogenesis of bronchial asthma has increased substantially over the past decade. This has been accompanied by the introduction of a range of new drugs for the treatment of this disorder, and the usage of anti-asthma drugs is increasing. Despite these changes and an increased awareness of the disease, asthma remains the only "preventable" disease where the morbidity and mortality are still increasing in most parts of the world. This "asthma paradox" requires explanation, and this article is an attempt to provide a plausible scientific one. The hypothesis expresses concern that a long recognised, but little publicised, pharmacological property of the drug class most widely prescribed for the treatment of asthma, the beta 2-adrenoceptor agonists--namely, the inhibition of mast-cell degranulation--may be contributing to the world wide increase in morbidity and mortality from asthma via the inhibition of a natural anti-inflammatory mechanism.

Evidence for protein kinase C--independent pathways mediating phorbol ester induced plasmacytoid differentiation of B chronic lymphocytic leukemia cells

The effects of phorbol esters on many cell types are known to be mediated through activation of the protein kinase C (PKC) signal transduction pathway. By using the specific inhibitor of this enzyme 1-(5-isoquinolinylsulfonyl)-2-methyl-piperazine dihydrochloride (H7) we have assessed the role of PKC activation in phorbol ester (phorbol 12-myristate 13-acetate, PMA)-induced plasmacytoid differentiation of B chronic lymphocytic leukemia cells (B-CLL) as a model of terminal differentiation of human B lymphocytes. H7 affected a dose-dependent inhibition of PMA-induced thymidine and uridine uptake with ID50 values of 41 microM and 32 microM, respectively. A comparable ID50 value (34 microM) was obtained for H7 inhibition of B-CLL PKC activity in a cell-free system. PMA-induced changes in cell morphology, expression of CD20, CD37 and FMC7 surface antigens together with increased secretion of immunoglobulin were variably abrogated by H7 suggesting that PKC activation is more important in B cell activation/DNA synthesis than in the differentiative response. Consistent with this, expression of a sizable proportion of PMA-inducible genes was not significantly affected by H7. These data are consistent with the existence of a PMA-activated, PKC-independent signal transduction pathway which may be important, though by itself apparently insufficient, for eliciting full terminal differentiation in B lymphocytes.

Tin compounds inhibit the plasma cell response to metallic tin. Transfer of inhibition by parabiosis

Injection of metallic tin powder causes intense proliferation of plasma cells in draining lymph nodes of Lewis rats. Pretreatment orally with soluble tin salts prevents this response to subsequently injected metallic tin. In the present work, pretreatment with tin salts by parenteral injection was just as effective as addition to the drinking water. This new approach made the following experiments possible. Poorly soluble tin compounds were found to be inhibitory when injected parenterally. Tin salts injected parenterally into one of two rats joined in parabiotic union prevented the plasma cell response to metallic tin in both parabionts. The transfer of the inhibitory effect via the cross-circulating blood represents significant progress toward understanding the mechanisms involved. The evidence suggests the possibility that tin salts elicit an intermediary substance or process that is responsible for inhibition of the plasma cell response to metallic tin.

Effects of prolonged low-level cadmium exposure on the tadpole immune system

Uninjected (Group I) and sheep erythrocyte (SRBC)-injected (Group II) Rana tadpoles were exposed to varying sublethal concentrations of cadmium (Cd) for 6 weeks. In order to assess possible effects on the tadpole immune system we determined pre-B, B mu, and plasma cell (PC mu) frequencies in liver and mesonephros of Group I larvae, and hemagglutinating antibody (HA) titers of Group II animals. Group I and Group II control animals were cultivated in water with no added Cd (0 ppm), while treatments were set at 0.1, 0.2, 0.4 and 0.8 ppm Cd. We found that (a) Cd appeared to stimulate a significant increase in the frequency of B mu cells in animals treated at 0.4 and 0.8 ppm, (b) certain treated Group II larvae contained significantly increased amounts of HA in their serum, while their serum protein concentrations were not significantly different, and (c) there was a dose-related increase in tissue Cd levels in treated Group II larvae. Our observations suggest that chronic low-level exposure to Cd may (a) result in a slight increases in the frequency of B mu cells in unimmunized animals, (b) increase immune responsiveness of immunized larvae, and (c) increase liver and mesonephros accumulations of Cd. Preliminary studies indicated that cytosolic Cd is associated with a protein which appears to be similar to mammalian metallothionein.

Malignant plasma cells are sensitive to LAK cell lysis: pre-clinical and clinical studies of interleukin 2 in the treatment of multiple myeloma

To assess the role of the cytokine interleukin 2 (IL2) in the treatment of patients with multiple myeloma, we examined the sensitivity of plasma cell lines and malignant plasma cells from multiple myeloma (MM) patients to cell and cytokine-mediated killing induced by IL2. Unstimulated peripheral blood mononuclear cells (PBM) from normal donors produced little killing (mean lysis 1.0 +/- 1.0%, effector:target (ET) ratio 50:1), but cytotoxicity was modestly increased when PBM were incubated with IL2 prior to assay (8.0 +/- 2.9%). Unstimulated PBM from patients with MM also failed to kill autologous malignant plasma cells (mean 0.6 +/- 0.6%), but after exposure to IL2 they induced substantial lysis of autologous malignant cells (mean 55.3 +/- 22.1%). In addition, tumour necrosis factor (TNF) and interferon-gamma (IFN-gamma), two cytokines released from mononuclear cells in response to IL2, also reduced the survival and thymidine uptake of malignant plasma cells in culture. To determine whether these potentially beneficial immunomodulatory effects could be reproduced by in vivo administration of IL2, we have administered seven courses of IL2 to four patients with MM after autologous bone marrow transplant (ABMT). No serious adverse effects were noted. Increases in natural killer (NK) and lymphokine-activated killer (LAK) activity of PBM occurred during IL2 infusion, although cells capable of killing autologous MM cells did not circulate. However, IL2 infusions also induced substantial increases in the production of the cytokines TNF and IFN-gamma from peripheral blood lymphocytes. These results suggest that the in vivo administration of IL2 in MM deserves further evaluation, particularly for its potential to control minimal residual disease.

Coupling of early response gene expression to distinct regulatory pathways during alpha-interferon and phorbol ester-induced plasmacytoid differentiation of B chronic lymphocytic leukaemia cells

Phorbol esters (phorbol 12-myristate 13-acetate; PMA) and alpha-interferon (alpha-IFN) act through divergent signal transduction pathways to induce B chronic lymphocytic leukaemia cells (B-CLL) to undergo plasmacytoid differentiation in vitro. By using a panel of PMA-inducible early response gene probes we show that these two different effectors are coupled to second messenger pathways that do not converge on a common gene regulatory programme in differentiation of B-CLL cells. Moreover, using the calcium ionophore, A23187, four distinct regulatory classes of early response gene could be defined implying that multiple regulatory pathways may mediate the process of terminal differentiation in B lymphocytes.

Purification and properties of a new ribosome-inactivating protein with RNA N-glycosidase activity suitable for immunotoxin preparation from the seeds of Momordica cochinchinensis

A ribosome-inactivating protein similar to those already known (Stirpe and Barbieri (1986) FEBS Lett. 195, 1-8) was purified from the seeds of Momordica cochinchinensis. This protein, for which the name of momorcochin-S is proposed, is a glycoprotein, has an Mr of approx. 30,000, and an alkaline isoelectric point and can be considered as an iso-form of the previously purified momorcochin from the roots of M. cochinchinensis. Momorcochin-S inhibits protein synthesis by a rabbit-reticulocyte lysate and phenylalanine polymerization by isolated ribosomes, and alters rRNA in a similar manner as the A-chain of ricin and related toxins (Endo et al. (1987) J. Biol. Chem. 262, 5908-5912). Momorcochin-S was linked to a monoclonal antibody (8A) against human plasma cells, and the resulting immunotoxin was selectively toxic to target cells.

Expression of the major rheumatoid factor cross-reactive idiotype in juvenile rheumatoid arthritis

The major rheumatoid factor cross-reactive idiotype (RF-CRI), defined by prototypic monoclonal IgM rheumatoid factors, is expressed in high frequency by pokeweed mitogen-derived plasma cells from patients with rheumatoid arthritis who express RF in their sera. Unlike adults with rheumatoid arthritis, most patients with juvenile rheumatoid arthritis are seronegative for RF, as detected by classic IgG binding assays. We report that approximately 50% of seronegative patients with juvenile rheumatoid arthritis express the RF-CRI in high frequency among their pokeweed mitogen-derived plasma cells, and that approximately 33% of patients express the RF-CRI in high titer in their sera. The possible mechanisms for expression of an idiotypic marker of RF without expression of IgG binding activity by classic assays are discussed.

VAD chemotherapy for refractory multiple myeloma

Thirty-four patients with refractory multiple myeloma were treated with 4-d continuous infusions of vincristine and adriamycin in combination with 4-d pulsed high-dose dexamethasone (VAD). Of 31 evaluable patients, 16 entered a complete remission (50%) and three a partial remission (10%). No difference in response rate was observed between primary refractory and relapsed patients. The median response duration was 9 months and the median survival of the responding patients was 12 months versus 4 months for the non-responders. Ten patients have currently survived longer than 360 d, of which six are stable in complete remission without therapy. All responding patients showed a remarkable improvement of their performance status and 70% of these patients became pain-free. Bacterial infection was the major complication and was probably due to the intensive corticosteroid programme. Severe myelosuppression was rarely observed. Irrespective of the response to VAD, a high beta 2-microglobulin of 4 micrograms/ml or more was a bad prognostic parameter. As early relapses were seen especially in this group of patients, in the patients with a plasma-cell LI% of 3 or more, and in patients with previous anthracyclin treatment, early consolidation, with, for instance, high dose melphalan, might improve the prognosis for these patients.

[The thymus in exposure to pain]

The effect of isotonic solution and microtrauma of the gastrocnemius muscle to the structure and cell composition in various zones of the thymus has been studied on mature white male rats on the first, 7th and 14th days of the experiment. At injection of the isotonic solution (sodium chloride) the part of small lymphocytes decreases and that of the large and middle ones--increases (it is mostly manifested on the 7th day of the experiment). The amount of immature plasma cells increases sharply at the same time, and that of mature cells--fluctuates during the experiment. The number of the mitotically dividing cells decreases. To some extent grows the part of the reticuloepitheliocytes; this demonstrates that migration of the lymphoid line cells from the thymus becomes greater. Pricks of the syringe needle do not produce any statistically significant changes.

[Morphological bases for the resistance of the intestines to the action of cholera toxoid]

Effect of antigen (cholera toxoid) has been studied on distribution of specific antibody-containing plasma cells in the lamina propria of the mucous membrane of the guinea pig small and large intestine. Since it is known that experimental cholera is easily reproduced in these animals, amount of plasmocytes is determined after primary intraperitoneal and secondary intraduodenal immunization with cholera toxoid. At the primary immunization maximal increase in amount of plasmocytes is noted in the jejunum on the 70th day; at the secondary--on the 19th day. At the primary parenteral immunization of the animals with the antigen, the intensity of the immune response in the lamina propria of the mucous membrane increases. At the secondary immunization the local immunity is more manifested in comparison with the primary one.

LPS augments human B-cell differentiation by direct stimulation of PWM-responsive B cells

Bacterial lipopolysaccharide (LPS) augments production of IgM and IgG by two- to seven-fold in cultures of peripheral blood lymphocytes (PBL) stimulated by pokeweed mitogen (PWM), but only if monocytes are rigorously depleted. When PBL were separated into adherent cell (AC), B-cell-enriched, and T-cell-enriched fractions, pulsed with LPS, and recombined in culture with PWM, increased generation of plasma cells was seen only in cultures containing LPS-treated B cells. This effect of LPS appears to be independent of soluble factors. Supernatants from LPS-stimulated B cells or AC did not consistently increase PWM responses when cultured with fresh B cells in the presence of polymyxin B. Furthermore, pulsing of B cells with purified interleukin 1 from two different commercial sources failed to augment PWM-induced differentiation. When B cells were depleted of surface IgD (sIgD)-bearing cells by panning, no effect on LPS-mediated augmentation of PWM-driven differentiation was seen. B cells were also fractionated by rosetting with mouse erythrocytes. Treatment of BMR+ cells with LPS did not induce them to respond to PWM, while treatment of BMR- cells with LPS augmented generation of plasma cells. These results indicate that LPS acts directly to augment differentiation of PWM-responsive B cells, rather than recruiting sIgD+, BMR+ cells to become PWM responsive.

A method for evaluating regional effects of cytotoxic drugs on proliferating cells in lymph nodes

Tin powder, injected into both hindfeet of rats, caused intense proliferation of the plasma cell series in the draining lymph nodes. The hyperplasia was evaluated by weight and by histology of the nodes. This simple, rapidly executed model was used to evaluate the delivery of locally injected cytotoxic drugs to regional lymph nodes. Inhibition of hyperplasia was compared to both internal controls (contralateral node) and external controls. Mitoxantrone and methotrexate, injected locally according to certain doses and schedules, were effective in reducing the lymph node hyperplasia with little or no systemic effects. This model should assist in the evaluation of drugs, schedules, and adjuvants that might be used in the regional treatment of lymph node hyperplasia or metastic neoplasia.

Lymphotoxic activity of methyl prednisolone in vitro--I. Comparative toxicity of methyl prednisolone in human cell lines of B and T origin

The cytotoxic activity of methyl prednisolone was compared in EB-3(B), NALM-6(B), CCRF-CEM(T) and RPMI-8226 (plasma cell) cell lines derived from human lymphoid malignancies. Whereas EB-3 cells were steroid-sensitive, NALM-6 cells were partially sensitive and CCRF-CEM and RPMI-8226 were steroid resistant at concentrations of methyl prednisolone up to 10(-4) M. A high concentration of methyl prednisolone, 2.5 X 10(-3) M was toxic to all cell lines. Steroid-sensitivity did not correlate with the incorporation of [3H] dexamethasone and could not be mimicked by flurbiprofen, a non-steroidal anti-inflammatory agent. Both theophylline and di-butyryl cAMP were toxic towards NALM-6, EB-3 and CCRF-CEM cells; however, this toxicity was reversible and did not reflect the cells' sensitivities towards methyl prednisolone. Furthermore, elevated levels of cAMP in theophylline-treated cells, were not demonstrable in cells treated with methyl prednisolone at toxic or non-toxic concentrations of the steroid. Steroid-sensitive EB-3 cells exposed to 10(-5) M methyl prednisolone, produced a soluble factor which was toxic CCRF-CEM cells.

Chloroquine and ammonium chloride prevent terminal glycosylation of immunoglobulins in plasma cells without affecting secretion

The generation of an acidic pH in intracellular organelles is required for several membrane and protein recycling processes. For instance, the internalization of ligands by receptor-mediated endocytosis is followed by the development of an acidic pH inside endosomes; this allows dissociation of the ligand, which is then transported to the lysosomes, from the receptor, which is recycled to the cell surface. There is evidence that part of this recycling process involves the distal region of the Golgi complex, where terminal glycosylation occurs: when the plasma membrane transferrin receptor is desialylated by neuraminidase treatment, it acquires new sialic acid molecules after endocytosis and before cell-surface re-expression. Golgi membranes have been shown to contain a proton pump and the distal Golgi cisternae appear to have an acidic content. Here, we have studied the effects of chloroquine and ammonium chloride, which raise the pH of acidic intracellular compartments, on the processing and secretion of immunoglobulins by plasma cells. Sialic acid transfer to terminal galactose residues, a reaction known to occur in the distal Golgi shortly before secretion, is completely and rapidly inhibited in the presence of these drugs, without significant modification of the secretion rate. This effect is accompanied by a dilatation of the Golgi cisternae and is not rapidly reversible.

Effects of oestradiol-17 beta and progesterone on the number of plasma cells in uteri of ovariectomized mice

Immunoglobulins A and G were localized by immunoperoxidase labelling in uteri of ovariectomized mice treated with oestradiol-17 beta and progesterone. The administration of oestradiol or progesterone alone to ovariectomized mice for 3 days increased the number of IgA plasma cells from about 1 to 14 per histological section. When the two hormones were administered simultaneously for 3 days the number of plasma cells per section was equal to or greater than with either hormone alone. Treatment with oestradiol followed by progesterone in a sequence that prepares the uterus for implantation resulted in about 31 IgA plasma cells per section. Counts of IgG plasma cells showed similar trends but the numbers were smaller. The results indicate that progesterone increases rather than decreases the number of plasma cells in the mouse uterus. This is consistent with observations on intact mice during oestrus and pregnancy and suggests that the marked increase in endometrial plasma cells at the time of implantation in mice is a response to progesterone acting on an oestrogen-primed uterus.

Avian immune capacity and bone marrow cellularity after in ovo treatment with cyclophosphamide

Lymphoid tissue, immunity and erythropoiesis in bone marrow were studied in chickens which had received air cell applications of cyclophosphamide (Cy) between 16 and 18 days of their embryonic development. The bursae from the Cy-treated birds were reduced significantly in size, deficient in bursal follicles, and lacked lymphocytes. The agglutinin level of sheep red blood cells of birds treated with Cy (2 mg) as 16, 17 and 18-day embryos was significantly lower than controls. While these Cy-treated birds lacked IgG antibody to sheep red blood cells, about 50% of the Cy birds produced unspecific IgG. Cy treatment did not suppress the graft-versus-host response. Cy did not change the absolute number of lymphocytes, granulocytes or erythroid series of cells in the bone marrow but did eliminate plasma cells. Since some of the Cy-treated birds did not produce specific agglutinin but made Ig, one would have to conclude that the presence of the bursa was not obligatory for Ig synthesis, but that the bursal microenvironment may be a prerequisite for synthesis of specific antibody.

Rate of M-component changes and plasma cell labeling index in 25 patients with multiple myeloma treated with peptichemio

Twenty-five consecutive patients with previously untreated multiple myeloma were studied for bone marrow plasma cell labeling index, response to peptichemio induction therapy, and rate of M-component (MC) changes during the course of the disease. They received intermittent melphalan or cyclophosphamide as maintenance therapy and peptichemio associated with vincristine at first relapse. The response rate (76%) was independent of clinical stage, evaluated according to Merlini et al and to Durie and Salmon. Among responsive patients, rapid responders (half-life of MC decrease less than 47 days for IgA and IgG and less than 29 days for light chain myelomas) had a bone marrow plasma cell labeling index significantly higher (P less than 0.01) than that of slow responders. Rapid responders had a median survival of 15 months, while slow responders had a median survival of 42 months (P less than 0.05). The difference in survival between the two groups was accounted for mainly by the difference in duration of first response and the different rates of MC increase following it. Both of these parameters were directly related to the half-life of MC decrease at response in IgA and IgG myelomas. The duration of second response and the half-life of MC increase following it were shorter than the duration of first response and than the half-life of MC increase at first relapse.

[Mesenteric lymph nodes in the rat after exposure to hydrocortisone]

The construction and cell composition of the cortex and medulla have been morphometrically studied after 1-, 3-, 5-, 7- and 14-aliquot injection of medical doses of hydrocortisone (0.25 mg per 100 g of body mass). The body mass of the animals decreases, as does the size of the mesenteric lymph nodes. The lymphocyto- and immunocytopoietic functions intensify in the medullary cords with a simultaneous inhibition of these processes in the cortical plateau and in the lymphoid noduli. On the 5th and 7th days there is some increase in the section area of the cortex, while that of the medulla decreases. The part of small lymphocytes in these structures grows large. Therefore, it is possible to suppose a definite tendency towards restoration of the structural components within two weeks.

[Features of the structure of the spleen and lymph nodes of the rat after exposure to the secretion of the suprascapular gland of the toad]

Zootoxin of the toad suprascapular glands in the dose of 0.5 mg/kg of the body mass (rat) increases mitotic activity of lymphoid cells in B-dependent zones of the lymph nodes and spleen. Simultaneously, mitotic activity of cells in T-dependent zones of the spleen also increases.

The effect of methotrexate on in vitro immunoglobulin production

The effect of Methotrexate (MTX) on pokeweed mitogen (PWM) induced immunoglobulin (Ig) production in vitro was studied over a range of 10(-4) - 10(-12)M MTX, using an enzyme-linked-immunosorbent assay (ELISA). MTX, at a concentration of 5 X 10(-9)M profoundly decreased all classes of Ig production, IgM greater than IgG greater than IgA. Plasma cell numbers, identified using polyclonal antihuman immunoglobulin, demonstrated a similar sensitivity to MTX. There was a paradoxical increase in IgM and IgG production at 5 X 10(-11)M MTX. Clinical implications of these findings are discussed.

A granulocyte colony-stimulating factor from serum-free cultures of RSP-2 X P 3 cells: its separation from a macrophage colony-stimulating factor and its biological and molecular characterization

A granulocyte colony-stimulating factor (G-CSF) was highly purified from the serum-free culture medium of RSP -2 X P3 cells. The G-CSF had an apparent molecular weight of 33,000 as determined by high speed gel permeation chromatography, but its molecular weight was decreased to 15,000 by 0.1% sodium dodecyl sulfate. A small amount of monocyte/macrophage CSF (M-CSF) also was separated from the same medium. The production of this M-CSF was increased markedly by bacterial lipopolysaccharides. The M-CSF had an apparent molecular weight of 77,000 in the absence of 0.1% SDS and 49,000 in its presence. The G-CSF was stable against 5 mM dithiothreitol, whereas the M-CSF was slowly inactivated. The two CSFs also differed in their heat-stability and resistance to trypsin. Neuraminidase changed the isoelectric point of both CSFs. Anti-L cell CSF serum severely inhibited the activity of M-CSF but not that of G-CSF. A 1 : 1 mixture of M-CSF and G-CSF developed colonies of the respective types, both in excess of the number predicted. The RSP -2 X P3 G-CSF reported here should prove very useful in the study of differentiation in myeloid stem cells.

Prednisone pulse therapy for refractory myeloma

The utility of vindesine and a frequent prednisone schedule was evaluated in 70 patients with refractory myeloma. No patient responded to vindesine alone, but about one-fourth achieved significant tumor reductions from intermittent high-dose prednisone, either alone or in combination with vindesine. Forty-seven percent responded when prednisone pulses were combined with vincristine and doxorubicin, providing the best results yet achieved in our patients with refractory myeloma. In responding patients, remissions were of excellent quality and survival was prolonged significantly. These results supported the utility of a more frequent corticosteroid schedule with increased doxorubicin dose in patients with advanced and resistant multiple myeloma.

Tin salts prevent the plasma cell response to metallic tin in Lewis rats

Inoculation of metallic tin powder produced marked proliferation of plasma cells and Russell body cells in draining lymph nodes. Prior, but not concurrent, administration of a soluble tin salt in the drinking water prevented the plasma cell hyperplasia. Various Na, Zn, Ag, and Cu salts were not inhibitory. The inhibitory effect of tin salts was detected as long as 2 months after the pretreatment was stopped. If the plasma cell response to metallic tin were due to an immunologic reaction, then the inhibition by a soluble tin salt may be a form of immunologic tolerance.

Heavy chain loss after treatment with Melphalan in a patient with "nonsecretory" myeloma

A case of "nonsecretory" myeloma is described. The patient had typical osteolytic lesions and marked infiltration of myeloma cells in the bone marrow, and plasma cell leukemia. A good partial remission was obtained with Melphalan, but the patient relapsed and died one year later. Immunofluorescent and immunoelectroscopic studies on the myeloma cells demonstrated the presence of cytoplasmic gamma-and kappa-chains at the initial stage and of only kappa-chains at a relapse. The electron microscopic method for polysome analysis indicated that both L-and H-chains were synthesized on membrane-bound polysomes initially, but the ability to produce H-chain was missing at the relapse.

[Therapeutic effectiveness of gentamycin and rifampicin in experimental staphylococcal-Pseudomonas aeruginosa infection and their effect on immunological processes]

The survival level of the experimental animals with infection caused by Staphylococcus and Ps. aeruginosa was the highest when the animals were treated with a combination of gentamicin and rifampicin as compared to the use of every antibiotic alone. The combination had a more favourable effect on the plasmocytic reaction and production of the antibody-forming cells in the lymphoid organs which correlated with the therapeutic efficacy of the antibiotics.