Migratory behavior of lymphocytes with specific reactivity to alloantigens. II. Selective recruitment to lymphoid cell allografts and their draining lymph nodes

The use of antibody-secreting cell probes to reveal tissue-restricted immune responses during infection

Antibody secreting cell probes (ASC-probes) were generated from the hepatic lymph node (HLN), mesenteric lymph node (MLN) and spleen of rats after infection with the liver fluke, Fasciola hepatica, and used to probe Western blots of parasite antigens. In chronic primary infections, parasite-specific antibodies were only detected in ASC-probes derived from HLN. Seven days after a secondary infection, a restricted response was detected in ASC-probes from the MLN, directed predominantly against an antigen specific to the newly excysted juvenile (NEJ) stage. This NEJ-specific antigen was only recognized by HLN if the second infection was not rejected and the challenge flukes reached the liver. Measurement of the immunoglobulin levels present in the ASC-probes showed significant elevation only in lymph nodes draining sites of recent infection. In addition, when the isotype profiles were determined in ASC-probes derived from different lymph nodes, it was observed that they showed different isotype preferences, in particular IgA for the MLN, IgE for HL.N and IgM for spleen. These results show that discrete and independent immune responses occur in different body compartments of a rat against different stages of a parasite.

Participation of serotoninergic system in neuroimmunomodulation: intraimmune mechanisms and the pathways providing an inhibitory effect

Exogenous serotonin administration as well as its precursor 5-oxytryptophan, blockade of the ferment inactivation by MAO inhibition, impairment of the monoamine binding, in other words, all the ways of elevation of active serotonin level, result in the inhibition of the immune response. On the contrary, exclusion of the serotoninergic system by the nuclei raphe lesion and the blockade of the synthesis ferments by p-chlorphenylalanine and p-chloramphetamine stimulates it. The present analysis permits us to conclude that the nuclei raphe serotoninergic system provides an inhibitory mechanism of the immune response modulation, that is realized via the hypothalamus-hypophysis-adrenals axis. Immune response modulation by the extraimmune control system is possible only be means of the mechanisms that are present in the immunocompetent system. Investigation of the cellular basis of physiological mechanisms of serotoninergic regulation of the immune process made it possible to determine alterations in the correlation of functionally different cell populations in animals with elevated serotonin level. An inhibitory action which serotonin produces upon the immunogenesis, is based on the attenuation of suppressor cell function, an earlier than under the normal immune response development emergence of suppressor in the population of cell organs, and their longer presence, that is to some extent connected with the redistribution of cell populations in the immunocompetent organs. After serotonin administration only the antigen-nonspecific immunosuppression is activated. In evolutionary terms the mechanisms of nonspecific suppression have been formed earlier than those of specific ones (Calkins & Stutman, 1978; Mijawaki, Seki, Kubo & Tanigushi, 1979). It is quite reasonable that extraimmune modulation, and psychoneuroimmunomodulation by monoamine systems in particular, can be performed by means of this ancient antigen-nonspecific mechanism of the immune response regulation. In this case, the modulation of immunological reactivity should correspond to these endogenous and environmental influences. Thus, activation of the nonspecific suppression induced through the serotoninergic system can be considered as the universal mechanism which on the one hand completes control of the immune homeostasis and on the other may be the precondition of the development of pathological states caused by the reduction of immunological status.

Expression of immunity to intravaginal herpes simplex virus type 2 infection in the genital tract and associated lymph nodes

Herpes simplex virus type 2 is a human venereal pathogen which causes lethal neurological illness after intravaginal inoculation into BALB/cJ mice. In the present studies, we demonstrate that intravaginal vaccination with an attenuated strain of this virus, which possesses a partial deletion of the thymidine kinase gene, rapidly induced durable immunity to lethal intravaginal challenge with wild-type virus. Such immunity was characterized by a dramatic hyperplasia of genital lymph nodes and a significant reduction in wild-type virus replication and spread from the genital tract following lethal challenge. Of greater importance, immunity to lethal wild-type virus challenge in the genital tract was transferrable to non-immune mice with genital lymph node cells prepared 1 week after intravaginal vaccination but was not transferrable with serum or cells from other lymphoid organs tested at this time. The adoptive transfer of anti-viral immunity to wild-type challenge was also characterized by a diminution in wild-type virus replication and spread from the genital tract. These results suggest that an important component of cellular immunity to genital pathogens may be antigenic stimulation of genital lymph nodes.

Characteristics and functions of Sendai virus-specific T-cell clones

Several murine Sendai virus-specific T-cell clones were characterized in vitro and in vivo. All T-cell clones were phenotypically Thy-1.2+, and most clones were Lyt-1+,2-; one T-cell clone was Lyt-1-,2-. Some of the clones proliferated in response to antigen presented on I region-compatible stimulator cells. Proliferation could be inhibited by monoclonal antibodies directed against class II antigens. Clones which proliferated in response to antigen secreted lymphokines which could be identified as Interleukin 2 and Interleukin 3. All of the clones tested in vivo induced a delayed-type hypersensitivity response in syngeneic mice challenged with antigens. Depending on the experimental conditions chosen, Interleukin 2-producing clones as well as non-Interleukin 2-producing clones mediated help for stimulation of cytolytic T lymphocytes.

Induction of immunological memory in the skin. Role of local T cell retention

Using an experimental contact sensitivity model in guinea-pigs, evidence is presented that hapten (DNCB or oxazolone) specific T lymphocytes may persist for several months in previous sites of inflammation. Immunological memory, revealed by accelerated contact skin reactions upon retesting with the hapten, was limited to the original contact skin reaction sites. This 'local skin memory' to DNCB or oxazolone could be induced in both specific and non-specific skin inflammatory reactions, provided the animals had been sensitized to the hapten not longer than 2 weeks before. In animals which had been sensitized more than 1 month earlier, local skin memory could be induced if the animals received a booster application of hapten shortly (0-2 days) before primary skin testing. From these results we conclude that recently activated T cells may enter inflammatory sites non-specifically, producing specific local immunological memory. This memory may last several months. Accumulation of hapten specific T cells at inflammatory sites may be important in retest reactivity, in flare-up reactivity and in chronic inflammation.

Redistribution of renal allograft-responding leukocytes during rejection. II. Kinetics and specificity

We investigated the traffic of allograft-responding leukocytes between the host and graft without handling of these cells in vitro. The blood flow between the host and graft was disconnected, the proliferating cells were labeled with [3H]thymidine selectively in the graft or in the host, the label was chased with cold thymidine, and the circulation was reestablished. The localization of labeled cells was quantitated by autoradiography. The first host-derived labeled cells appeared in the graft and graft-derived labeled cells in the host, already on the 1st d after transplantation. This was followed by an exponential increase in the labeled cell traffic in both directions. The peak of traffic was observed on day 4 after transplantation, whereafter the traffic rapidly declined and tapered off. This decline was not due to exhaustion of supply, as the labeled cells continued to proliferate in their original compartments, nor to a slowdown of blood circulation, which took place 2-3 d later. We consider the decline to indicate that the rejection has proceeded to a (irreversible) stage autonomous of the host lymphatic and hematopoietic system. During the exponential increase, nearly one-third of the graft-infiltrating inflammatory cells were replaced as a consequence of relocalization during each 18-h-period. All mononuclear white cell types, with the exception of granulocytes, participated in the traffic. Most lymphoid cells entrapped in the graft were descendents of recent cell divisions; most of the mononuclear phagocytes derived from a preexisting phagocyte pool. The entrapment of labeled leukocytes in a relevant graft was specific: when an allograft and an autograft were simultaneously transplanted, a more than 50-fold entrapment was observed in the allograft, compared with the autograft. Very few of the cells localized in irrelevant positions, such as the liver and lung, of the recipient.

Quantitation of proliferative and cytotoxic precursor cells directed against human tumours: limiting dilution analysis in peripheral blood and at the tumour site

Blood and tumour-infiltrating lymphocytes (TIL) from 16 cancer patients have been examined under limiting dilution conditions to determine the frequency of cells responding in mixed tumour-lymphocyte cultures (MLTC) to autologous tumour and Interleukin-2 (IL-2). Tumour-derived lymphocytes showed a high spontaneous response to IL-2 alone 1/1,900 in TIL; 1/6,000 in PBL suggesting the presence of "activated" T cells in situ. Proliferative frequencies were increased in MLTC in both blood (1/3,779) and TIL (1/1,084). Phenotypic analyses showed that total T-cell contents of the responder populations were comparable but TIL were enriched for the OKT8+ subset with a corresponding reduction in OKT4+. TIL showed increased numbers of OKMI+ and Tac+ lymphocytes. The major cytotoxic precursor expanding under these conditions was reactive against autologous tumour. K562 (NK) were present at a lesser frequency--particularly in TIL. The data show a concentration and activation of reactive lymphocytes at the tumour site and establish conditions for the clonal expansion of specifically cytotoxic T cells.

Interferon inhibits the generation of allospecific suppressor T lymphocytes

The effect of human interferon alpha on the differentiation of functional populations of lymphocytes during the human allogeneic response in vitro was studied. Interferon alpha inhibited the generation of allospecific suppressor T lymphocytes that normally develop from lymphocytes primed in vitro against allogeneic cells. This effect was not the result of the destruction by interferon of precursor suppressor cells but rather to inhibition of their differentiation into active suppressor T lymphocytes. This inhibition was reversible and could be overcome by repeated allogeneic stimulation even in the presence of interferon. Inhibition of the generation of allospecific suppressor lymphocytes by interferon might play an important role in the allogeneic response. Interferon inhibited the proliferation of lymphocytes after allogeneic stimulation in a primary mixed lymphocyte reaction but enhanced their cytotoxicity. Despite the inhibitory effect in the primary mixed lymphocyte reaction, the specific secondary proliferative response of lymphocytes primed against a single HLA-DR antigen was only slightly affected by interferon. On the other hand, the nonspecific secondary proliferative response of lymphocytes primed in the presence of interferon was significantly reduced, indicating that interferon might decrease the recruitment of nonspecific "irrelevant" clones of responding cells during the sensitization period.

Role of autologous lymphocyte cytotoxicity in colonic neoplasia

The T-lymphocyte mediated killing of autologous carcinoma colon cells was investigated. There was no change in the incidence of activity with advanced disease, age, or nutritional status of the patient and no difference could be demonstrated in lymphocytes extracted from blood, draining lymph nodes, or the tumour itself. Nevertheless. T-lymphocyte activity did appear to be specific for the patients's own tumour, as it was rarely observed with allogeneic tumours. There was also no correlation with lymphocyte natural killer activity. The in vitro studies demonstrated patient specific T-lymphocyte activity in 23 of 47 patients with carcinoma of the colon, but the results do not correlate with clinical and pathological findings.

Specific and non-specific lymphocyte cytotoxicity in colon carcinoma

The cytotoxic activity of peripheral-blood (PBL), lymph-node (LNC) and tumour-infiltrating lymphocytes (TIL) from 47 patients undergoing surgery for colon carcinoma (Duke's Stage A, 1 patient; B, 24; C, 15 and C with metastases, 7) was examined in short-term 51Cr-release assays, against fresh autologous tumour cells, allogeneic colon cancer cells and the erythroleukaemia cell line, K562. Cytotoxicity against autologous cells was detected in at least one effector population in 23/47 patients (49%), with overall frequencies which did not differ for patients in different Duke's stages of disease. By contrast, lysis of allogeneic tumour cells was infrequent (11%) regardless of the effector population to which they were exposed. Cytotoxicity against K562, cells highly sensitive to NK activity, though variable, was detected in 93% of PBL of normal donors and 83% of patients, and among the latter showed no evidence of significant decline with advancing disease. However, LNC and TIL anti-K562 activity was infrequent (17%) in concordance with previous reports. There was no correlation between the ability of patients' PBL to lyse autologous tumour and K562 cells. The independence of these 2 cytotoxic actions was further explored in studies fractionating lymphocytes: autologous tumour killing was augmented in T-enriched PBL; whereas the greatest anti-K562 activity was found in the corresponding non-T fraction. Lymphocyte cytotoxicity in colonic neoplasia is thus manifest in 2 apparently independent lymphocyte populations; a relatively specific killer T-cell population, detectable in PBL, LNC and TIL, which is preferentially reactive with the autologous cells; and a non-specific killer population, largely limited to PBL, with the properties of NK cells. The activity of neither population reflects the clinical status of patients with this disease.

Canine transmissible venereal sarcoma: distribution of T and B lymphocytes in blood, draining lymph nodes and tumours at different stages of growth

The levels of T, B and null lymphocytes in the peripheral blood, draining lymph nodes, and tumour masses at different growth stages in dogs transplanted with canine transmissible venereal sarcoma (CTVS) were determined by immunofluorescence techniques. The tumours were classified at excision into "progressor", "steady state", and "regressor" stages of growth. The percentage of B cells in the lymphocytes infiltrating into the progressively growing tumours (n = 10, 37.3 +/- 7.4%) was significantly higher (P less than 0.025) than that in regressing tumours (n = 21, 26.1 +/- 1.9%). In contrast, the percentage of T cells in the lymphocytes infiltrating into the regressing tumours (n = 21, 61.2 +/- 2.6%) was significantly higher (P less than 0.005) than that in the progressively growing tumours (n = 10, 34.0 +/- 5.1%). The tumours at the steady-state growth stage (n = 9) had 50.8 +/- 5.7% infiltrating T-cells, which was significantly higher (P less than 0.005) than the progressors and lower (P less than 0.005) than the regressors. The percentage of null cells of progressors (n = 10, 26.0 +/- 6.9%) was significantly (P less than 0.025) higher than in regressors (n = 21, 13.5 +/- 2.9%). The draining lymph nodes of progressor dogs (n = 5) had significantly fewer (P less than 0.025) B cells (8.2 +/- 2.3%) than in normal (n = 5, 16.1 +/- 3.1%), regressors (n = 12, 19.1 +/- 1.7%) and steady-state dogs (n = 5, 15.8 +/- 2.6%). Although there was slight lymphopenia and fluctuation of null cells, no significant differences in T- and B-lymphocyte levels were noted in the peripheral blood of the tumour dogs (n = 44) studied.

Lymphocytes infiltrating human breast cancers lack K-cell activity and show low levels of NK-cell activity

Lymphocytes infiltrating human primary mammary carcinomas lack ADCC and show low levels of natural cytotoxicity. The peripheral blood lymphocytes, however, show a variable but prominent level of cytotoxicity. Lymphocyte preparations from breast tumours, when mixed with autologous blood lymphocytes, significantly suppress their prominent killer- (K- and NK-) cell activities.

Specific selection of antigen-reactive lymphocytes into antigenically stimulated lymph nodes in sheep

Sheep were primed to a variety of antigens and the efferent lymphatic from a popliteal lymph node was cannulated. The cannulated node was challenged repeatedly with PPD and all the lymph and cells removed from the animal. During this time the PBL were monitored for reactivity to all antigens (purified protein derivative of tuberculin [PPD], johnin, and keyhole limpet hemocyanin [KLH]) by the vitro transformation assay. The response of these cells to PPD was found to be gradually eliminated after repeated challenge of the cannulated node with that antigen. The response to the other antigens was unimpaired. No depletion of this response to PPD occurred in cannulated sheep when the antigen was given into a noncannulated node. In vivo delayed-type hypersensitivity skin test and helper T cell assays confirmed that there is a specific selection of antigen-reactive cells from the recirculating lymphocyte pool into antigen-stimulated lymph nodes.

H-2 restriction for lymphocyte homing into lymph nodes

Migratory patterns into lymph nodes of labeled spleen lymphocytes, injected intravenously, showed considerable differences according to the genetic identity or disparity of donor and recipient mice. The use of mice carrying different H-2 haplotypes in the same B 10 background, or, conversely, the same H-2b haplotype in different backgrounds, showed that no homing was observed in the case of complete disparity at the H-2 complex, contrasting with optimal homing in the case of H-2 identity. Homing was not influenced by disparity at the genetic background. Irradiation of recipient mice did not change the results and suggested that no immunological host-vs.-graft reaction was involved in the H-2 restriction observed. The use of donor-recipient pairs carrying recombinant H-2 haplotypes showed that a single H-2 K and/or H-2 D identity allowed almost optimal homing. The results indirectly suggested that an immunological graft-vs.-host reaction was not involved in the phenomenon but rather a positive recognition of H-2 K or H-2 D identity between donor and recipient cells.