The migration of lymphocytes into rat popliteal lymph nodes during antigenic promotion or competition between heterologous erythrocytes

The injection of chicken and sheep red blood cells (CRBC and SRBC) into rat popliteal lymph nodes either together or sequentially 2, 4, 6, or 8 days apart resulted in an enhanced immune response when the second antigen was injected 2 or 4 days after the injection of the first antigen (antigenic promotion) or a suppressed immune response when the second antigen was injected 6 days after the injection of the first antigen (antigenic competition). The immune response to either antigen was dependent upon the time of administration of the second antigen with respect to the first antigen. Lymphocyte migration into antigenically stimulated lymph nodes was greater when the two antigens were injected sequentially rather than together. Further, the migration of lymphocytes into the lymph node was enhanced when the second antigen was injected during the inductive or suppressive phase of the immune response to the first antigen (CRBC) regardless of whether the same (CRBC) or an antigenically unrelated antigen (SRBC) was used as the second antigen. While antigenic promotion may in part be explained by the increased rate at which lymphocytes migrate into lymph nodes, lymphocyte migration is also enhanced during antigenic competition. This suggests that while suppressor cells/factors may regulate the effector phase of an immune response they do not directly modulate the migration of blood-borne lymphocytes into the lymph node.     

The therapeutic effect of OK-432-combined adoptive immunotherapy against liver metastases from gastric or colorectal cancers

Twenty-four patients with liver metastases from gastric or colorectal cancer were treated with OK-432-combined adoptive immunotherapy (AIT). Lymphocytes isolated from regional lymph nodes or peripheral blood were cultured with medium containing T cell growth factor and sonicated tumor extract antigen (SE-Ag) for 9–13 days. The cultured lymphocytes were transferred mainly through the hepatic artery after the administration of OK-432, a streptococcal preparation. Sixteen of the 24 patients received a low dose of anti-cancer agents between the OK-432 injection and cell transfer. When cultured without SE-Ag, regional lymph node lymphocytes (RLNL) showed significantly (P<0.05) higher cytotoxic activity against autologous tumor cells and, on the contrary, lower cytotoxic activity against K562 than peripheral blood lymphocytes (PBL). When cultured with SE-Ag, cytotoxicity of RLNL against autologous tumor cells was nearly equivalent to that of PBL. The blastogenesis of fresh PBL to SE-Ag was significantly (P<0.05) augmented after the OK-432-combined AIT. Two patients showed complete response and 4 patients showed partial response among 19 patients who had evaluable lesions. Five patients whose liver metastases were resected were treated with OK-432-combined AIT as an adjuvant therapy. To date they are alive without recurrence in the liver.Abbreviations AIT adoptive immunotherapy - RLNL regional lymph node lymphocytes - SE-Ag sonicated tumor extract antigen     

Analysis of the intralesional adriamycin-induced regression of primary and metastatic growth of line-10 guinea-pig hepatoma

Summary A single intralesional injection of 2.4 mg adriamycin/kg into 7-day-old intradermal strain-2 guinea-pig hepatoma, line-10, caused regression of the tumor and prevented the growth of regional lymph node metastasis. Cured animals were resistant to challenge with the same tumor. Intratumoral injection of 20 mg DTIC/kg was not effective in causing tumor regression or preventing growth of regional lymph node metastasis. Comparative histological examinations performed on the tumor site and the draining lymph node showed that both chemotherapeutic drugs caused extensive necrosis at the injection site and that within 7 days only adriamycin eradicated tumor cells from the draining lymph nodes.The number of host lymphocytes and monocytes in the adriamycin-treated tumor sites was less than that seen in the saline- or DTIC-injected animals at all time intervals examined. Minimal peripheral effects, as measured by total and differential analysis of the blood, were noted in drug-treated normal and tumor-bearing animals. In addition, the concentration of drug used did not interfere with the development of immunity.The results suggest that the effect(s) of intralesional adriamycin treatment is probably caused by a combination of cytotoxic and cytostatic actions of the drug and the development of tumor-specific immunity. Abbreviations used: DTIC, 5-(3,3-dimethyl-1-triazeno)-imidazole-4-carboximide; BCNU, 1,3-bis-(2-chloroethyl)-1-nitrosourea; SDA, superficial distal axillary lymph node     

Collateral presentation of antigens as physiological prototype for lymph node metastases

The formation of lymphogenic metastases remains enigmatic. In particular, the much more pronounced predilection of carcinomas than of sarcomas to metastasizing into regional lymph nodes is an unsolved problem. We suggest that this difference could be due to the ability of epitheliocytes for a hypothetical process termed by us “collateral presentation of antigens”. Under conditions of infection of epithelium with intracellular pathogens or during inflammation, epithelial cells acquire a special receptor phenotype, undergo the epithelial-mesenchymal transition, and migrate along lymphatic vessels into lymph nodes where they present antigen to immunocytes. The collateral presentation of antigens can be of significant biological importance in the case of insufficient classical pathway of antigen presentation (by dendritic cells) or on disturbance in the death mechanisms of the infected cells. Depending on conditions of induction of the epithelial-mesenchymal transition and on possible ability of epitheliocytes to express MHC II with co-stimulating molecules, two pathways, “container-mediated” and “MHC II-dependent”, of antigen presentation in lymph nodes resulting in development of immunogenesis or anergy of immunocytes are supposed to exist. All pathways of delivery of the epithelial cells into lymph nodes and of antigen presentation by epitheliocytes terminate by death of these cells. The lymphogenic metastasizing realizes the same mechanism under conditions of tumor disease; however, this is not associated with cell death, but they actively colonize the lymph node. The proposed hypothesis allows us to explain the metastasizing of sarcomas into lymph nodes. The main prerequisite for lymphogenic metastasizing seems to be related with the mesenchymal-epithelial transition of sarcoma cells promoting their involvement in the presentation of antigens.     

Mechanisms of in vivo generation of cytotoxic activity against allograft: 1. Local differentiation of mature cytotoxic T lymphocytes in rejection of allogeneic lymphocytes

Although cytotoxic activity was not detected within the spleen and regional lymph nodes from mice immunized sc with allogeneic lymphocytes, such activity was detected consistently in glass-nonadherent and anti-θ-sensitive peritoneal exudate cells (PE cells) from Day 5 after immunization and reached a maximum by Day 7. Immunized spleen cells developed cytotoxic T lymphocytes (CTLs) earlier and more effectively than normal spleen cells when transferred ip into X-irradiated syngeneic normal mice together with immunizing antigen, while they did not become cytotoxic when transferred without antigen. These results suggest that spleen and lymph node cells which may have differentiated into some transitional state by in vivo immunization may differentiate into mature CTLs, following direct contact with antigen at the site of graft. CTLs generated there appear to be responsible for the rejection of allogeneic lymphocytes. Cytotoxicity of PE cells was also generated in X-irradiated mice and augmented cytotoxicity was generated by treatment with cyclophosphamide.     

Tumour-associated proliferative responses in vitro of regional lymph nodes draining solid cancers in man

Summary The proliferative responses in vitro of tumourdraining lymph node lymphocytes were evaluated against autologous colon and lung carcinoma cells. The reactivity of lymphocytes appeared to be directed against tumour-associated rather than tumour-specific antigens. The lymphocyte reactivity detected was not due to an autologous mixed lymphocyte reaction. Recombinant interleukin-2 augmented the responses detected but not their tumour specificity. Phenotypic characterisation indicated the presence of T suppressor/cytotoxic (TS/C) cells as well as natural killer (NK) cells. Only the latter, however, were active in functional cytotoxicity assays. The inability to generate both tumour-specific proliferation of tumour-draining lymph node lymphocytes and tumour-specific cytotoxic killer cells may be due to the presence of suppressor cells in the regional lymph nodes; preliminary data suggest the presence of such cells.Part of this project was supported by a grant from Cancer Research Campaign     

Model for mediastinal lymph node metastasis produced by orthotopic intrapulmonary implantation of lung cancer cells in mice

This study is designed to establish a pulmonary tumor model to investigate the biology and therapy of lung cancer in mice. Current methods for forming a solitary intrapulmonary nodule and subsequent metastasis to mediastinal lymph nodes are not well defined. Lewis lung carcinoma cell (LLC) suspensions were orthotopically introduced into the lung parenchyma of C57/BL6 mice via a limited skin incision without thoracotomy followed by direct puncture through the intercostal space. The implantation process was performed within approximately 50 sec per mouse, and the operative mortality was less than 5%. Single pulmonary nodules developed at the implanted site in 93% of animals and subsequent mediastinal lymph nodes metastasis were observed in all mice that were succeeded to form a lung nodule after intrapulmonary implantation. The size of tumor nodule and the weight of mediastinal lymph node increased in a time-dependent manner. The mean survival time of mice implanted successfully with LLC cells was 21 +/- 2 days (range; 19-24 days). Histopathological analysis revealed that no metastatic tumor was detectable in the mediastinal lymph nodes on day 11, but metastatic foci at mediastinal lymph nodes were clearly observed on days 17 and 21 after implantation. Other metastases in distant organs or lymph nodes were not observed at 21 days after the implantation. Comparative studies with intrapleural and intravenous injections of LLC cells suggest that the mediastinal lymph node metastasis by intrapulmonary implantation is due to the release of tumor cells from the primary nodule, and not due to extrapulmonary leakage of cells. An intravenous administration of CDDP on day 1 after tumor implantation tended to suppress the primary tumor nodule and significantly inhibited the lymph node metastasis. Thus, a solitary pulmonary tumor nodule model with lymph node metastasis approximates clinical lung cancer, and may provide a useful basis for lung cancer research.     

T and B lymphocyte migration into syngeneic tumors.

The migration of splenic T and B lymphocytes into syngeneic tumors undergoing immunologic rejection was investigates. Spleen cells were obtained from normal BALC/c mice or BALB/c mice bearing tumors induced by murine sarcoma virus (MSV). Either whole spleen cells or immunoabsorbent purified T and B cells were radiolabeled with sodium chromate-51 and injected i.v. into normal or MSV inducted-tumor bearing syngeneic recipients. Twenty-four hours later the recipient mice were sacrificed and radioactivity was assessed for tumor, contralateral normal muscle, the lymph nodes draining the tumor and contralateral draining lymph nodes, peripheral lymph nodes, spleen, and liver. Both T and B lymphocytes from either normal or MSV tumor-bearing animals show greatly increased migration into the tumor when compared with normal muscle. Migration of T cells from both normal and MSV tumor bearers was 30 times that of migration to normal muscle. B cells from tumor-bearing mice, on the other hand, localized in the tumor itself only 50% as frequently as did B cells from normal animals. In addition, T cells from MSV tumor bearers were found in the highest proportion in the lymph node draining the tumor site. We conclude that T and B lymphocytes from either normal or tumor-bearing mice migrate to a syngeneic tumor undergoing immunologic rejection. In contrast, the migration of both T and B cells from tumor-bearing animals was decreased to the peripheral lymph nodes at the time of maximum tumor growth.     

Specific tumor memory induced by polyethylene-glycol-modified interleukin-2 requires both helper and cytotoxic T cells

Local polyethylene-glycol (PEG)-modified interleukin-2 (IL-2) immunotherapy of the guinea pig Line 10 (L10) tumor was previously demonstrated to evoke long-lasting systemic immunity after cure of the tumor and metastases. T cells, most likely the helper T cell subpopulation, were demonstrated to be crucial to the antitumor effects. Here we show that systemic immunity is induced within 7 days after the start of PEG-IL-2 therapy, indicating a rapid systemic priming of L10-specific T cells. No in vitro cytotoxic activity was detected in cell suspensions obtained from the primary tumor site, the regional lymph node or the spleen when isolated during (days 21 and 28) intratumoral treatment with 200 000 IU PEG-IL-2. These data confirm our carlier results obtained with 60 000 IU PEG-IL-2. Moreover, no cytolytic activity was observed in the chromium-release assay after in vitro restimulation with irradiated tumor cells. Specific L10 immunity can be transferred using spleen cell suspensions. Depletion of such a suspension of helper T cells resulted in rejection of the primary tumor in two out of four animals, but all the guinea pigs developed lymph node metastases. Removal of the cytotoxic/suppressor phenotype caused rejection of the dermal tumor in four of eight guinea pigs, but the capacity to prevent lymph node metastases was retained in all animals. Thus, depletion of either subtype reduces, but does not abrogate, the capacity to transfer L10 immunity with spleen cells. In conclusion, our data suggest that tumor cell killing through direct T cell cytotoxicity is not the main mode of action in PEG-IL-2-induced L10 tumor regression, PEG-IL-2 therapy induces early systemic immunity, resulting in rejection of a distant tumor, and the transfer of this immunity depends mainly on the presence of helper T cells, although cytotoxic T cells may also play a role.     

Cell-mediated immunity in interstitial nephritis. II. T lymphocyte effector mechanisms in nephritic guinea pigs: analysis of the renotropic migration and cytotoxic response.

The present studies investigate the effector role of lymphocytes in guinea pigs with an interstitial nephritis. Several observations were made relative to a number of functions expressed by these cells. The results of adoptive cell migration studies suggest that a subpopulation of T cells in nephritic animals traffic renotropically to either normal or damaged kidneys on transfer. Similar lymphocytes were also tested in vitro for direct effector function by utilizing target kidney cell monolayers in a cell-mediated cytotoxicity assay. The kinetics of the observed cytotoxic response were studied over the life span of nephritic animals. Optimal target-cell lysis occurred 12 to 17 days after sensitization, simultaneous with the onset of active histopathologic changes. The cytotoxicity was stoichiometrically titratable and relatively specific for fetal kidney tissue. In addition, cells from the spleen or lymph nodes of diseased animals effectively suppressed this cytotoxic response. These findings demonstrate that a diverse population of T lymphocytes are both capable of damaging the renal interstitium as well as modulating effector-cell functions on a regional basis with the immune system.     

Antigen-specific T cell activation and proliferation during oral tolerance induction

One of several routes of achieving immunologic tolerance is through functional inactivation of Ag-specific T cells. Oral administration of Ag can allow survival of the Ag-specific T cells that are functionally anergic. The aim of this study was to investigate whether functional inactivation of Ag-specific T cells is directed through an activation process and to further define the differentiative pathways and functional characteristics of anergic T cells. Mice were transplanted with OVA-specific TCR-transgenic T cells and either fed OVA or immunized s.c. with the OVA peptide 323-339 in CFA. OVA-specific T cells from OVA-fed mice were unresponsive to restimulation in vitro within 48-72 h after treatment. In vivo, however, T cell proliferation was detected by 5, 6-carboxy-succinimidyl-fluoresceine-ester intensity changes in OVA-specific T cells. The mesenteric lymph nodes (LNs) from OVA-fed mice more frequently contained OVA-specific dividing cells in vivo than those in the peripheral LNs, and the reciprocal was observed following s.c. immunization of the OVA peptide in CFA. The induction of anergy in OVA-fed mice was accompanied by rapid up-regulation of CD69 and CTLA-4, later down-regulation of CD45RB on OVA-specific T cells, and a marked decrease in T cell secretion of IL-2, IL-10, and IFN-gamma after OVA restimulation in vitro. Results from this study indicate that the inductive phase of oral tolerance is preceded by Ag-specific T cell activation in vivo, proliferation in the regional draining LNs, and differentiation into a memory-like state. These results indicate that Ag-directed differentiation occurs as a part of T cell tolerance through anergy.     

Regulatory T cells prevent CD8 T cell maturation by inhibiting CD4 Th cells at tumor sites

Natural regulatory T cells (Tregs) are present in high frequencies among tumor-infiltrating lymphocytes and in draining lymph nodes, supposedly facilitating tumor development. To investigate their role in controlling local immune responses, we analyzed intratumoral T cell accumulation and function in the presence or absence of Tregs. Tumors that grew in normal BALB/c mice injected with the 4T1 tumor cell line were highly infiltrated by Tregs, CD4 and CD8 cells, all having unique characteristics. Most infiltrating Tregs expressed low levels of CD25Rs and Foxp3. They did not proliferate even in the presence of IL-2 but maintained a strong suppressor activity. CD4 T cells were profoundly anergic and CD8 T cell proliferation and cytotoxicity were severely impaired. Depletion of Tregs modified the characteristics of tumor infiltrates. Tumors were initially invaded by activated CD4(+)CD25(-) T cells, which produced IL-2 and IFN-gamma. This was followed by the recruitment of highly cytotoxic CD8(+) T cells at tumor sites leading to tumor rejection. The beneficial effect of Treg depletion in tumor regression was abrogated when CD4 helper cells were also depleted. These findings indicate that the massive infiltration of tumors by Tregs prevents the development of a successful helper response. The Tregs in our model prevent Th cell activation and subsequent development of efficient CD8 T cell activity required for the control of tumor growth.     

Lymph node metastasis of soft tissue tumors: a cytomorphologic study

OBJECTIVE: To study the frequency of regional lymph node metastasis of soft tissue tumors (STT) and to evaluate the utility of fine needle aspiration cytology (FNAC) as an initial investigative modality. STUDY DESIGN: A prospective and retrospective study of over 6 years (1998-2004) was performed to look for frequency of STT metastasizing to lymph nodes. FNAC of enlarged nodes was performed as a routine outpatient procedure after obtaining complete clinical details. Histopathology and immunohistochemistry were correlated where available. RESULTS: Lymph node enlargement was seen in 23 of 241 patients with STTs, of which 19 cases showed involvement (7.88%), synchronous with primary in 12 cases and metachronous in 7 cases. The most common sites of primary tumor were the lower extremity and head and neck region with involved regional lymph nodes. STTs commonly involving lymph nodes were rhabdomyosarcoma and extraskeletal Ewing's/primitive neuroectodermal tumor (PNET); other rare tumors included malignant granular cell tumor, epithelioid hemangioendothelioma, mediastinal ganglioneuroblastoma, angiosarcoma and epithelioid sarcoma. CONCLUSION: Lymph node aspirates should be examined for alien cells, particularly smears that are paucicellular and demonstrate cystic change. Lymph node metastasis of STT is rare and influences staging, treatment and prognosis. Enlarged regional nodes should be examined with FNAC.     

Systemic IL-1 and adjuvant treatment of an experimental tumor

In this investigation, systemic administration of interleukin-1 (IL-1) and local adjuvant therapy were shown to modify immunological parameters associated with the lymphatics draining the site of experimental tumor inoculation. These immunological parameters were shown to be modified early (within 7 days) following tumor inoculation and within the time period of IL-1 administration. IL-1 induced a marked increase in the number of lymphocytes within the brachial and axillary lymph nodes associated with the tumor inoculation site. This increase was characterized by an overall augmentation in the number of CD8⁺ and CD4⁺ lymphocytes.In vitro, these lymph node cells showed enhanced proliferation in response to interleukin-2 (IL-2) when compared to non-IL-1 treated animals, and were capable of mounting a potentially greater cytotoxic response for both NK sensitive and NK resistant tumor targets. Without IL-1 administration, temporal and sequential lymph node cellular changes were observed, but were diminished and delayed when compared to the IL-1 treated animals. By adoptive transfer of tumor resistance, lymph node cells from IL-1 treated animals were demonstrated to be tumor-protectivein vivo. These results demonstrate that systemic IL-1 induces regional changes in the lymphatics of mice undergoing primary tumor challenge with adjuvant therapy and that these changes result in tumor protection for the host.     

Major histocompatibility complex class II antigen expression on leucocyte subpopulations in the draining lymph node and tumour in the early phase of bacillus-Calmette-Guérin-induced tumour regression

Summary We investigated the cellular composition and the major histocompatibility complex (MHC) class II antigen expression in the draining lymph node and the tumour during potentiation of the immune response by intralesional bacillus Calmette-Guérin (BCG) administration in the line 10 hepatocellular carcinoma in the strain 2 guinea-pig. Five days after its injection BCG induced a ninefold increase in the number of draining lymph node cells and an increased MHC class II expression. This increased MHC class II expression was mostly due to the selective increase of B cells in the lymph nodes, and to a lesser extent to the increase of T cells expressing MHC class II antigens. Taking into account this nine-fold increase, intralesional treatment of BCG increased considerably the number of T helper/inducer (anti-CT7) and T suppressor/cytotoxic (anti-CT6) lymph node cells expressing MHC class II antigen. The percentage of tumourinfiltrating T cells expressing MHC class II antigen in the tumour was higher than the percentage of T cells in the regional draining lymph node of non-treated guinea-pigs, indicating the presence of activated T cells in the tumour. After treatment with BCG no further increase in MHC class II expression was measured in the tumour, nor was any phenotypical change of the tumour-infiltrating T cells found. In conclusion, with the use of two-colour flow cytofluorometry we have shown that the potentiation of the already existing immune response to line 10 is accompanied by a considerable increase in T helper/inducer, T suppressor/cytotoxic cells and MHC class II antigen in the regional lymph node. Whether this is essential for the potentiation of the immune response causing tumour regression and long-lasting immunity is a subject for further study.     

In situ lymphoid cells of mouse mammary tumors. IV. Comparison of functional activity of lymphoid cells separated from mammary tumors to that of spleen and lymph node cells of tumor-sensitized mice.

Lymphoid cells isolated form several types of mouse mammary tumors are capable of stimulating tumor cell growth or survival in MCT assays. Lymph node and spleen cells of mice bearing such a tumor are specifically cytotoxic to the tumor cells. Surgical removal of the tumor is followed in 4 to 7 days by the appearance of stimulatory capacity in spleens and lymph nodes. By day 10, cytotoxic cells specific for the sensitizing tumor are again detected. These reach a peak on day 13. By day 17 no reactivity is detectable. The functional distribution of tumor-reactive lymphoid cells is different between tumor masses and peripheral lymphoid organs.     

Herpes simplex virus type 1-specific cytotoxic T-lymphocyte arming occurs within lymph nodes draining the site of cutaneous infection

Various studies have shown that major histocompatibility complex class I-restricted cytotoxic T lymphocytes (CTL) can be isolated from lymph nodes draining sites of cutaneous infection with herpes simplex virus type 1 (HSV-1). Invariably, detection of this cytolytic activity appeared to require some level of in vitro culture of the isolated lymph node cells, usually for 3 days, in the absence of exogenous viral antigen. This in vitro "resting" period was thought to represent the phase during which committed CD8(+) T cells become "armed" killers after leaving the lymph nodes and prior to their entry into infected tissue as effector CTL. In this study we reexamined the issue of CTL appearance in the HSV-1 immune response and found that cytolytic activity can be isolated directly from draining lymph nodes, although at levels considerably below those found after in vitro culture. By using T-cell receptor elements that represent effective markers for class I-restricted T cells specific for an immunodominant glycoprotein B (gB) determinant from HSV-1, we show that the increase in cytotoxicity apparent after in vitro culture closely mirrors the expansion of gB-specific CTL during the same period. Taken together, our results suggest that HSV-1-specific CTL priming does not appear to require any level of cytolytic machinery arming outside the lymph node compartment despite the absence of any detectable infection within that site.     

Effect of sizofiran on regional lymph nodes in patients with head and neck cancer

The immunomodulating effects of preoperative sizofiran (SPG) administration on regional lymph nodes were studied in patients with stage III or IV head and neck cancer, by comparing the immunofunction of peripheral blood. The regional lymph nodes were dissected surgically, and freshly obtained mononuclear cells were studied to investigate the interleukin-2 (IL-2) production, the LAK and NK activities, and the quantitative analysis of the surface phenotype of the mononuclear cells. The results indicated that SPG enhanced immunological activities in the regional lymph nodes, as shown by increased IL-2 production and cytotoxic activities of the effector cells (NK, LAK), and increased helper T lymphocytes (CD4⁺) in the tumor-uninvolved lymph nodes. The immunofunction following SPG administration was attenuated, but was still augmented in the regional lymph nodes with metastases. Therefore, SPG was found to be a biologic response modifier to enhance the immunofunctions of the regional lymph node in patients with head and neck cancer.     

Functional analysis of mononuclear cells infiltrating into tumors. II. Differential ability of mononuclear cells obtained from various tissues to produce helper factors that are involved in the generation of cytotoxic cells

The requirement of CGF in the generation of cytotoxic cells against syngeneic tumor cells (T-9) and in the rejection of transplanted T-9 cells has been investigated. Spleen cells obtained from sensitized rats showed strong cytotoxicity against 51Cr-labeled T-9 cells upon incubation with CGF for 48 hr. Human recombinant IL 2 and rat IFN failed to generate cytotoxic cells from spleen cells of sensitized rats. CGF are produced by spleen cells upon inoculation of T-9 cells into sensitized rats as a host in vivo immune response. Production of CGF preceded the appearance of cytotoxic cells in regional lymph node and tumor tissues. In those rats, inoculated tumor cells were eventually rejected. In contrast, spleen cells failed to produce CGF upon inoculation of T-9 cells in unsensitized rats. Cytotoxic cells were not detected in unsensitized rats, and inoculated tumor grew in those rats. Thus, CGF is likely to be involved in the generation of cytotoxic cells and in the rejection of inoculated syngeneic tumor cells. A Mono Q anion-exchange column with an FPLC system allowed the chromatographic separation of CGF from IL 1, IL 2, IL 3, and CSF.     

Correlation of cytotoxicity with experimental allergic encephalomyelitis.

Cytotoxicity of immune lymph node cells in experimental allergic encephalomyelitis (EAE) was maximal 9 days after injection of encephalitogenic emulsion. The ability of these cells to passively transfer EAE was also maximal at this time. Immune spleen cells were more cytotoxic than lymph node cells 9 days after injection; however, these cells did not passively transfer EAE. Twelve days after injection of encephalitogenic emulsion immune spleen cells passively transferred EAE with resulting mild histopathologic lesions. At this time the spleen cells were 50% more cytotoxic than comparable lymph node cells. Cyclophosphamide suppressed the development of clinical EAE and the development of cytotoxic lymphoid cells. It also reduced clinical signs and cytotoxic activity of lymph node cells. Spleen cell cytotoxic activity was enhanced by Cyclophosphamide. It was concluded that cytotoxic activity of lymph node and spleen cells was correlated with the ability of these cells to produce EAE. Lymph node cell populations differed qualitatively and/or quantitatively from immune spleen cell populations in EAE. Capacity to passively transfer EAE coincided with the maximal Cytotoxicity of the lymphoid cells from each tissue.