Systemic and local immunity in allograft and cancer rejection

LhANS-rr1, LhDFR, and LhMYB114 Regulate Anthocyanin Biosynthesis in Flower Buds of Lilium ‘Siberia’

The bulb formation of Lilium is affected by many physiological and biochemical phenomena, including flower bud differentiation, starch and sucrose accumulation, photoperiod, carbon fixation, plant hormone transduction, etc. The transcriptome analysis of flower buds of Lilium hybrid ‘Siberia’ at different maturity stages showed that floral bud formation is associated with the accumulation of anthocyanins. The results of HPLC-MS showed that cyanidin is the major anthocyanin found in Lilium ‘Siberia’. Transcriptome KEGG enrichment analysis and qRT-PCR validation showed that two genes related to flavonoid biosynthesis (LhANS-rr1 and LhDFR) were significantly up-regulated. The functional analysis of differential genes revealed that LhMYB114 was directly related to anthocyanin accumulation among 19 MYB transcription factors. Furthermore, the qRT-PCR results suggested that their expression patterns were very similar at different developmental stages of the lily bulbs. Virus-induced gene silencing (VIGS) revealed that down-regulation of LhANS-rr1, LhDFR, and LhMYB114 could directly lead to a decrease in anthocyanin accumulation, turning the purple phenotype into a white color. Moreover, this is the first report to reveal that LhMYB114 can regulate anthocyanin accumulation at the mature stage of lily bulbs. The accumulation of anthocyanins is an important sign of lily maturity. Therefore, these findings have laid a solid theoretical foundation for further discussion on lily bulb development in the future.

Flavonoids Accumulation in Fruit Peel and Expression Profiling of Related Genes in Purple (Passiflora edulis f. edulis) and Yellow (Passiflora edulis f. flavicarpa) Passion Fruits

Flavonoids play a key role as a secondary antioxidant defense system against different biotic and abiotic stresses, and also act as coloring compounds in various fruiting plants. In this study, fruit samples of purple (Passiflora edulis f. edulis) and yellow (Passiflora edulis f. flavicarpa) passion fruit were collected at five developmental stages (i.e., fruitlet, green, veraison, maturation, and ripening stage) from an orchard located at Nanping, Fujian, China. The contents of flavonoid, anthocyanin, proanthocyanin, and their metabolites were determined using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS), activities of key enzymes involved in flavonoid metabolism were measured, and expression profiling of related genes was done using quantitative real-time PCR (qRT-PCR). The results revealed that total flavonoids, anthocyanins, and procyanidins were found to be increased in the fruit peel of both cultivars with fruit maturity. Total flavonoids, anthocyanins, procyanidins, flavonoid metabolites (i.e., rutin, luteolin, and quercetin), and anthocyanin metabolites (i.e., cyanidin-3-O-glucoside chloride, peonidin-3-O-glucoside, and pelargonidin-3-O-glucoside) were found abundant in the peel of purple passion fruit, as compared to yellow passion fruit. Principle component analysis showed that the enzymes, i.e., C4H, 4CL, UFGT, and GST were maybe involved in the regulation of flavonoids metabolism in the peel of passion fruit cultivars. Meanwhile, PePAL4, Pe4CL2,3, PeCHS2, and PeGST7 may play an important role in flavonoid metabolism in fruit peel of the passion fruit. This study provides new insights for future elucidation of key mechanisms regulating flavonoids biosynthesis in passion fruit.

In vitro propagated dendritic cells from prostate cancer patients as a component of prostate cancer immunotherapy

T cell-mediated cancer immunotherapy requires efficient antigen-presenting cells. Dendritic cells (DCs) are arguably the most efficient antigen-presenting cells studied to date. Individuals with prostate cancer often undergo various therapies which may compromise their immune system, including the state of their DC precursors. We report the in vitro propagation of DCs from peripheral blood of patients with prostate cancer, most of whom are in clinical stages D1 or D2 and have undergone radiation therapy. After 7 days in culture, the number of DCs recovered were 20-50-fold higher than those isolated directly from peripheral blood. This number is comparable to findings of previous studies with healthy individuals. Cultured patients' DCs were capable of presenting tetanus toxoid to autologous T cells in vitro. Furthermore, T cells from 2 of 4 patients proliferated when cultured with their DCs and the lysate of a human prostate cancer cell line (LNCaP), demonstrating the potential role of autologous DCs in prostate cancer immunotherapy studies.

An inhibitor specific for the mouse T-cell associated serine proteinase 1 (TSP-1) inhibits the cytolytic potential of cytoplasmic granules but not of intact cytolytic T cells

We have investigated a proteinase inhibitor, designed according to the preferred amino acid sequence that is cleaved by the murine T-cell specific serine proteinase 1 (TSP-1) for its effect on the cytolytic potential of cloned cytotoxic T-cell lines (CTLL) and of cytoplasmic granules, derived from these cells. Pretreatment of effector cells with H-D-Pro-Phe-Arg-chloromethyl-ketone (PFR-CK) prior to the cytotoxicity assay did not result in inhibition of cytolytic activity of three independent CTLL and did not effect their granule-associated TSP-1 activity after extraction with Triton X-100. Furthermore, PFR-CK did not interfere with cytolysis of target cells by CTLL when present for the entire incubation period. In contrast, PFR-CK inhibited in a dose-dependent manner both TSP-1 activity and the hemolytic/cytolytic potential of isolated cytoplasmic granules after their pretreatment with high-salt concentration. We interpret these results to mean that cytolysis of target cells by CTLL involves the granule-associated proteinase TSP-1, which probably becomes active upon exocytosis following effector-target cell interactions.

Down-regulation of cytotoxic T lymphocyte generation by two distinct suppressor-cell systems

Two distinct suppressor systems have been described that are capable of down-regulating in vivo generation of cytotoxic T cells directed toward haptenaltered self-antigens. One system, induced by hapten, involves three T cells that others have shown to function sequentially to suppress DTH. The initiator of this cascade is a T cell that is readily induced in spleens of mice injected intravenously with syngenic membrane-coupled hapten. This Ts, when triggered by the same syngeneic membrane-coupled hapten that induced it, elaborates a factor. The other two Ts arise in lymph nodes and spleens of mice painted epidermally with hapten. One of the two Ts in this set is readily armed by the factor of the first Ts. The factor confers its specificity and genetic restriction upon the accepting Ts. The latter, when properly triggered, makes a factor that is taken up by its companion Ts, which actually suppresses by way of a nonspecific factor. Whereas this Ts cascade is operative at the efferent limb of DTH, it mediates suppression only at the afferent phase of the CTL response. A distinctly different suppressor system is induced by minor locus (Mls) antigen. When Mlsd lymphoid cells are injected intravenously into Mlsc-possessing mice, an Lyt-1+ T-suppressor cell is generated that can be found in the spleen as well as among peritoneal exudate cells. This Ts interacts with macrophages to accomplish nonspecific suppression of the CTL response that is detectable both in vivo as well as in vitro. A Ts soluble product has been found to be effective to suppress CTL generation in vitro only when macrophages are present in culture. The macrophage that accomplishes suppression is I-A-. Although the afferent limb of the CTL response is down-regulated by this suppressor system, our in vitro culturing system is so structured as to make the helper T cell inactive. Thus, the mechanism of suppression must be oriented to the other early participants in the response, namely, precursor CTL, helper and differentiation factors, and/or the antigen-presenting cell.

Monoclonal antibody analysis of mononuclear cells in myopathies. III: Immunoelectron microscopy aspects of cell-mediated muscle fiber injury

We have previously obtained light microscopical immunocytochemical evidence for cell-mediated muscle fiber injury and destruction in polymyositis and inclusion body myositis. To evaluate further interactions of the different cell phenotypes with each other and with the muscle fibers, the T8, T4, and Leu 7 markers in 7 cases of polymyositis and in 9 cases of inclusion body myositis were localized by immunoelectron microscopy. In the early stages of the cell-mediated process, T8+ cells and macrophages are apposed against, and/or send spikelike processes into, nonnecrotic muscle fibers. Leu-7+ cells penetrate fibers infrequently, and T4+ cells do not penetrate muscle fibers. Subsequently, an increasing number of T8+ cells and macrophages traverse the basal lamina; focally replace, displace, or compress the fiber; and spikes from these cells honeycomb the adjacent muscle fiber regions. The macrophages contain only few heterophagic vacuoles and therefore act in a cytotoxic rather than a phagocytic capacity. The integrity of the muscle fiber surface membrane facing the invading cells is maintained, but the possibility also exists that the membrane is damaged and rapidly repaired, or that the damage cannot be detected by electron microscopy. Nearby fiber regions often show either degenerative or regenerative changes. Ultimately, segments of the entire muscle fiber are replaced by the invading cells.

In situ effector pathways of allograft destruction. 3. Plasminogen activator activity in rat renal allografts

The question of which cell components in a rejecting rat renal allograft secrete plasminogen activator (PA) has been analyzed. Although normal renal parenchymal cells also secreted PA, most of the PA in a renal allograft (and to a lesser extent also in an autograft) was produced by the inflammatory leukocytes. Fractionation at 1 g demonstrated that the inflammatory cell population responsible for the PA production in the allograft sedimented together with the large mononuclear phagocytes (macrophages). Fractions purified for small blast cells and large lymphocytes did not contain any PA activity but they were able to induce resting peritoneal macrophages to produce PA when cocultured in vitro. The results demonstrate that the allograft-infiltrating mononuclear phagocytes are "activated" in the sense that they secrete PA and that the activation of mononuclear phagocytes at the site of inflammation may be partially regulated by the inflammatory lymphoid cells.

Monoclonal antibody analysis of mononuclear cells in myopathies. I: Quantitation of subsets according to diagnosis and sites of accumulation and demonstration and counts of muscle fibers invaded by T cells

In 76 muscle specimens (normal controls, 9; Duchenne dystrophy, 11; scleroderma, 11; dermatomyositis, 13; polymyositis, 15; inclusion body myositis, 17), mononuclear cells were analyzed at perivascular, perimysial, and endomysial sites of accumulation. Monoclonal antibodies reactive for B cells, T cells, T cell subsets, killer (K) or natural killer (NK) cells, and the Ia antigen were used for cell typing. Macrophages were identified by the acid phosphatase reaction. Few extravascular mononuclear cells occurred in normal muscle. In all inflammatory myopathies, a mixed exudate of T cells, B cells, and macrophages was present. Mature K/NK cells were rare in all diseases. In dermatomyositis, polymyositis, and inclusion body myositis, there was a positive gradient for T cells, T8+ cells, and activated T cells and a negative gradient for B cells and T4+ cells between perivascular and endomysial sites. In scleroderma the predominant perimysial exudate consisted mostly of T cells and macrophages. The percentage of B cells at all sites, and the T4+/T cell ratio in the endomysium, were significantly higher in dermatomyositis than in the other diseases. In polymyositis and inclusion body myositis, the endomysial exudate contained a large number of T cells, T8+ cells, and activated T cells but only sparse B cells. T cells accompanied by macrophages focally surrounded and invaded nonnecrotic fibers in polymyositis and inclusion body myositis. Rare fibers in Duchenne dystrophy and a very few fibers in dermatomyositis and scleroderma were similarly affected. We infer that (1) T-B, T-T, and T-macrophage cooperativities are likely to exist in muscle in different myopathies; (2) T cell-mediated fiber injury plays a role in polymyositis and inclusion body myositis; (3) T cell-mediated fiber injury can also occur in inherited diseases, such as Duchenne dystrophy; and (4) a local humoral response may occur in muscle in dermatomyositis and possibly in polymyositis and inclusion body myositis.

Monoclonal antibody analysis of mononuclear cells in myopathies. II: Phenotypes of autoinvasive cells in polymyositis and inclusion body myositis

In 6 cases of polymyositis and 6 of inclusion body myositis, phenotypes of mononuclear cells focally surrounding and invading muscle fibers were analyzed. By localizing the T8, T4, and Ia markers with direct immunofluorescence and acid phosphatase enzyme cytochemically in the same sections, five different phenotypes were simultaneously identified in a given section: T8+ and T4+ cells that were either activated (Ia+) or not activated (Ia-), and acid phosphatase--reactive and Ia+ macrophages. This approach permitted the separate and quantitative assessment of the distributions of the different phenotypes among the invading versus the surrounding cells. In both polymyositis and inclusion body myositis, the invading cells were selectively enriched in the T8+ phenotype. One-third of all invading cells and one-half of the invading T8+ cells were activated. T4+ cells were more abundant among the surrounding than the invading cells, and only a small proportion of the T4+ cells were activated. These findings are especially significant in view of the cytotoxic capability of the T8+ cells and because histocompatibility factors permit T8+ but not T4+ cells to recognize an antigen on muscle fibers. Macrophages accounted for 21 to 31% of the cells invading or surrounding nonnecrotic fibers. For purposes of comparison, we also analyzed mononuclear cells in necrotic fibers: 80% of these cells were macrophages, and only 20% were T cells. The findings indicate that in polymyositis and inclusion body myositis, nonnecrotic muscle fibers are injured by autoinvasive T8+ cells that act in concert with macrophages. Further, the findings strongly imply previous sensitization of clones of T cells to muscle fiber-associated surface antigen(s).

Purified mouse mammary tumor and lymphoid cells in immune assays

Tumor and lymphoid cell components from primary mammary adenocarcinomas of C3H/He mice were isolated simultaneously by velocity gradients. Viable tumor cells were obtained in sufficient numbers to test their in vivo and in vitro growth. Isolated tumor cells grew in 97% of inoculated syngeneic animals. In six assays with different tumors the effects of tumor-associated lymphoid cells (TAL) on in vivo tumor growth varied, enhancing in three and delaying in two experiments. Isolated tumor cells from animals with enhancing TAL grew faster in nonirradiated mice, whereas tumor cells from animals with inhibitory TAL grew better in irradiated animals. Isolated tumor cells also proliferated in cell culture, where they averaged 35% primary plating efficiency. Separated tumor cells were used in short-term 51Cr-release assays with TAL, tumor-bearer lymph node and spleen effectors. Cytotoxicity was detected in only five of 25 assays. In no case was there killing by lymphocyte populations from normal animals. In the present report we describe a technique for the isolation of viable tumor and lymphoid cells from murine adenocarcinomas that allows study of interactions between these populations from the original tumor-bearing host.

Inhibitory effect on monocyte-mediated cytotoxicity of sera from patients with multiple myeloma and malignant lymphoma

There was no difference in monocyte-mediated cytotoxicity between monocytes from patients with multiple myeloma or malignant lymphomas and monocytes from control persons after in vitro culture for 5 d. Cytostatic and cytolytic ability of lymphokine-activated monocytes cultured in medium with patient serum was significantly depressed compared to the ability of monocytes cultured with normal serum. A similar depression of cytostasis was found with non-activated monocytes of both patient and control origin. Sera from myeloma and lymphoma patients impaired the monocyte-mediated cytotoxicity equally.

Mononuclear-cell infiltration in ovarian cancer. III. Suppressor-cell and ADCC activity of macrophages from ascitic and solid ovarian tumours

Macrophages have been isolated from ascitic and collagenase-dispersed tumours from patients undergoing surgery for ovarian cancer. Macrophages were present in varying proportions in both sites, though the ration of macrophages to tumour cells was higher in ascites. Marked variation in size (as detected by sedimentation velocity) and cytochemical markers in the macrophages was noted. Highly enriched macrophage fractions were isolated from the ascites and collagenase-dispersed solid tumours by a combination of sedimentation velocity and selective EA RFC or adherence techniques. Suppressor activity in the PHA assay was detected in tumour macrophages (4/10 giving less than 50% inhibition), ascitic macrophages (1/15) and blood monocytes (2/7). Lymphocyte fractions from tumours were unresponsive to PHA and failed to suppress the blood response. Suppressor activity was also present in the purified tumour-cell fraction of 6/14 patients. ADCC activity was tested in a few patients. When the activity was determined against the SB target cells, tumour-derived macrophages were inactive, whereas the ascitic fraction showed low but significant activity which averaged much lower than patients blood values. The ADCC assays carried out with the CRC target cell indicated activity within the range of patient blood values in 4/4 ascites and 2/4 tumour macrophage fractions. Cytotoxicity was also assessed against co-purified autologous tumour cells. Although activity was detected in many of the tests, the results seemed to reflect target cell sensitivity. There appeared to be a correlation between cytotoxicity with test macrophages and normal blood mononuclear cells. The results indicate that the cytochemical heterogeneity and the variation in size between macrophage fractions is associated with a spectrum of activities.

Mononuclear-cell infiltration in ovarian cancer. II. Immune function of tumour and ascites-derived inflammatory cells

Mononuclear cell fractions were isolated from blood, ascites and solid tumours of patients undergoing surgery for Stages III and IV adenocarcinoma of the ovary, and evaluated for their response in NK, ADCC and PHA assays. Control experiments with the same fraction of normal blood indicated that these responses were not influenced by the enzymes used to isolate the tumour and ascites inflammatory cells. The inflammatory cell fractions isolated from both tumour sites which sedimented in the velocity range of blood mononuclear cells were adequate in number and composition for comparison with similar cells from blood. E RFC values in both ascites and tumour fractions exceeded those of patient blood. However, there was a marked difference in distribution of the T subsets between blood, ascites and tumour, which could cause the variable test results between the different cell sources. PHA responses of patient blood and ascites fractions were about half that of normal blood. Tumour-infiltrating lymphocytes (TIL) were less than 10% as responsive as normal blood. The depressed PHA responses of the TIL were not due to the presence of a suppressor cell population. NK activity of patient blood was less than that of normal blood, but not as much as the ascites of TIL cells. The activity of the ascites-derived lymphocytes was enhanced by treatment with interferon. ADCC activity against both CRBC and SB cells was normal or higher than controls in patient blood, and depressed in the ascites-derived fractions. TIL responded to less than 10% of the patient blood values. The results indicate a lack of response by ascitic and TIL cells in assays dependent on FcR-bearing effector cells and a greater loss of PHA-reactive cells from the tumour than from blood and ascites. These data could result from intratumour inactivation, or a failure of the particular subset to localize either in the ascites or the tumour site.

Systemic and in situ natural killer and suppressor cell activities in mice bearing progressively growing murine sarcoma-virus-induced tumors

The activity of systemic and in situ natural killer (NK) cells was measured in 3- to 5-week-old CBA mice with progressively growing murine sarcoma virus (MSV)-induced tumors. Splenic NK activity was depressed in tumor-bearing mice. NK activity was quite low or not detectable in unfractionated cell suspensions from the tumors 10-12 days after inoculation of virus, but activity was observed upon depletion of phagocytic and/or adherent cells. To determine whether this in situ inhibition of NK activity was correlated with the presence of previously described suppressor cells, subpopulations of cells from the tumors were tested for their ability to suppress various responses of normal spleen cells: NK activity, lymphoproliferative responses to concanavalin A, and proliferation-independent production of macrophage inhibition factor. A similar pattern of suppressor activity was seen in all of the assays, indicating the presence of pleiotropic suppressor cells in progressively growing MSV-induced tumors.

Separation of tumor-seeking small lymphocytes and tumor cells using Percoll velocity gradients

Using the polyoma virus-induced ascitic SEYF-a tumor, we evaluated isopycnic and velocity sedimentation gradients of Percoll as methods for separating tumor-seeking lymphocytes and tumor cells. It was established that the velocity sedimentation method is suitable for separation of small lymphocytes lodging within the SEYF-a tumor. This was confirmed by a serological analysis of the separated SEYF-a cell population. The results of this study strongly support our previously reported data demonstrating the in vivo coating of the tumor cells proper with potentially cytotoxic antibodies.