Thyroid, parathyroid, and salivary gland evaluations in patients exposed to multiple fluoroscopic examinations during tuberculosis therapy: a pilot study

The prevalence of thyroid, parathyroid, and salivary abnormalities was determined in 91 women who received an average of 112 fluoroscopic chest examinations during pneumothorax treatment for tuberculosis more than 40 yr previously and in 72 women treated for tuberculosis by other modalities. Thyroid abnormalities were determined by physical examination, scintiscans, and measurements of serum free T4 index, TSH, and thyroid microsomal antibodies. Thyroid nodules were diagnosed in 7.7% of the exposed and 4.2% of the comparison group (prevalence ratio, 1.8; 90% confidence interval 0.6-5.7). Autoimmune thyroid disease was diagnosed in 15.2% of the exposed and 6.9% of the comparison group (prevalence ratio, 2.2; 95% confidence interval, 0.8-6.2). No salivary tumors were detected. Two exposed women and 1 comparison woman had primary hyperparathyroidism. Although absorbed dose to the thyroid could not be precisely determined, approximately 60 rads would be expected to yield the observed excess of thyroid nodules. While the prevalence ratios were not significantly increased in the exposed group, the results suggest that susceptibility of the thyroid to nodules from cumulative radiation doses of this magnitude could be increased even when the doses are accumulated over years and that such x-ray exposure of the thyroid gland may predispose the patient to the development of autoimmune disease.

Efficacy in turkeys of spray vaccination with a temperature-sensitive mutant of Bordetella avium (Art Vax)

Broad-breasted white turkeys were vaccinated with a temperature-sensitive mutant of Bordetella avium (Art Vax) at 2 and 15 days of age and challenged at 22 days of age by contact with infected birds. Necropsy was performed at 35 days of age. Two vaccination protocols (eyedrop/oral and spray cabinet/spray bottle) and two challenge isolates (Arkansas 105 and North Carolina [NC] isolates) were used. Neither the spray nor the eyedrop/oral methods of vaccination prevented infection of the anterior trachea with either of the virulent challenge strains. The spray and eyedrop/oral methods of vaccination were equally effective in reducing the severity of gross lesions in the trachea. The vaccine reduced the severity of gross lesions in the tracheas of turkeys challenged with the NC isolate to a level approximately equal to that observed in unchallenged vaccinated controls, but the vaccine only moderately reduced the severity of lesions in birds challenged with the 105 isolate.

Extravasation of intravascular fluid mediated by the systemic administration of recombinant interleukin 2

Adoptive immunotherapy with lymphokine-activated killer cells and recombinant interleukin 2 (IL 2) can produce significant reduction of visceral metastases in tumor-bearing mice and, as shown recently, in humans with disseminated cancer. Because further dose escalations of IL 2 have been prevented by the development of a vascular leak syndrome (VLS) in both mice and humans, we investigated this VLS in mice undergoing the systemic administration of high-dose IL 2. A model for quantitating capillary permeability was used in which 125I-bovine serum albumin was injected i.v., and 2 hr later, tissues were counted in a gamma analyzer. A permeability index (PI) was calculated by dividing the mean counts per minute (cpm) of tissues from IL 2-treated mice by those from control animals. The injection of IL 2 produced increases in vascular permeability that were most pronounced in the thymus, spleen, lungs, liver, and kidneys (PI = 18.0, 10.0, 9.7, 6.7, and 6.3, respectively, on day 6). The development of the VLS was highly dependent on the number of days of IL 2 treatment (for example, the lungs contained 638, 1382, 3350, and 6187 cpm after 0, 1, 3, and 6 days of IL 2, respectively). Moreover, the degree of the VLS was directly related to the dose of IL 2 administered. Measurement of the wet and dry weights of lungs from IL 2-treated mice demonstrated that IL 2 produced a dramatic increase in their water weight (from 0.10 g at base line to 0.22 g after 200,000 U of IL 2 for 6 days). The injection of the IL 2 excipient failed to induce capillary leakage in tissues. Immunosuppression of mice by pretreatment irradiation (500 rad) or by injection of cyclophosphamide or by concurrent use of cortisone acetate markedly reduced or eliminated the development of the VLS. Similarly, the VLS was not observed in nude mice receiving IL 2. Thus, the administration of IL 2 produces a dose-limiting VLS that may be mediated, directly or indirectly, by host lymphoid elements.

Extravasation of intravascular fluid mediated by the systemic administration of recombinant interleukin 2

Adoptive immunotherapy with lymphokine-activated killer cells and recombinant interleukin 2 (IL 2) can produce significant reduction of visceral metastases in tumor-bearing mice and, as shown recently, in humans with disseminated cancer. Because further dose escalations of IL 2 have been prevented by the development of a vascular leak syndrome (VLS) in both mice and humans, we investigated this VLS in mice undergoing the systemic administration of high-dose IL 2. A model for quantitating capillary permeability was used in which 125I-bovine serum albumin was injected i.v., and 2 hr later, tissues were counted in a gamma analyzer. A permeability index (PI) was calculated by dividing the mean counts per minute (cpm) of tissues from IL 2-treated mice by those from control animals. The injection of IL 2 produced increases in vascular permeability that were most pronounced in the thymus, spleen, lungs, liver, and kidneys (PI = 18.0, 10.0, 9.7, 6.7, and 6.3, respectively, on day 6). The development of the VLS was highly dependent on the number of days of IL 2 treatment (for example, the lungs contained 638, 1382, 3350, and 6187 cpm after 0, 1, 3, and 6 days of IL 2, respectively). Moreover, the degree of the VLS was directly related to the dose of IL 2 administered. Measurement of the wet and dry weights of lungs from IL 2-treated mice demonstrated that IL 2 produced a dramatic increase in their water weight (from 0.10 g at base line to 0.22 g after 200,000 U of IL 2 for 6 days). The injection of the IL 2 excipient failed to induce capillary leakage in tissues. Immunosuppression of mice by pretreatment irradiation (500 rad) or by injection of cyclophosphamide or by concurrent use of cortisone acetate markedly reduced or eliminated the development of the VLS. Similarly, the VLS was not observed in nude mice receiving IL 2. Thus, the administration of IL 2 produces a dose-limiting VLS that may be mediated, directly or indirectly, by host lymphoid elements.

Adoptive immunotherapy of a syngeneic murine leukemia with a tumor-specific cytotoxic T cell clone and recombinant human interleukin 2: correlation with clonal IL 2 receptor expression

The successful adoptive immunotherapy of the syngeneic Friend virus-induced murine leukemia FBL-3 was mediated by a proliferative MHC-restricted, tumor-specific CTL clone in combination with recombinant human IL 2. This clone was previously shown to express the L3T4-, Lyt-1+, Lyt-2+ surface phenotype. Activation of the clone for 48 hr in vitro with irradiated tumor cells induced the expression of IL 2 receptors and markedly increased clonal proliferation in response to recombinant IL 2. Intravenous injection of 2 X 10(7) 48 hr in vitro-activated cloned cells, followed by 6 days of systemic (i.p.) administration of IL 2 resulted in the complete regression of tumors and the cure of 50% of the treated mice. IL 2 alone had no effect on tumor growth, whereas the injection of nonactivated (resting) clone plus IL 2 or activated clone without IL 2 had small but insignificant effects on tumor growth and survival. These results indicated that the in vivo effector functions of cloned T cells may be markedly enhanced by the concurrent systemic administration of recombinant IL 2 and by the induction of optimal IL 2 receptor expression on the cloned T cells at the time of cell administration.

Risk of extrathyroid tumors following radiation treatment in infancy for thymic enlargement

Two thousand eight hundred and fifty-six individuals who received X-ray treatments in infancy for an enlarged thymus gland and their 5053 nonirradiated siblings have been followed prospectively since 1953 to evaluate the risk of radiation-induced neoplastic disease. The health status of the entire cohort has been ascertained periodically by mail questionnaire survey. Based on the cumulative experience of five surveys of this cohort, the irradiated group has a statistically significant increased risk for both benign and malignant extrathyroid tumors, the age-adjusted relative risks being 2.0 and 2.2, respectively. Benign tumors of the bone, nervous system, salivary gland, skin, and breast (females only) and malignant tumors of the skin and breast (females only) account for the excess incidence of extrathyroid tumors among the thymic-irradiated individuals. Although a radiation-induced excess of extrathyroid tumors was suggested in an earlier survey of this cohort, small numbers restricted attribution of this excess to specific sites. The implications of these findings are discussed. Thyroid tumors are addressed in a separate paper.

Curative intravenous adoptive immunotherapy of Meth A murine sarcoma. A histologic and immunohistochemical assessment

Intravenous administration of 1.5 X 10(8) syngeneic spleen cells from immune animals resulted in the complete eradication of established Meth A soft tissue sarcomas in (C57BL/6 X BALB/c) F1 mice. In mice receiving a single injection of immune spleen cells 4 days after tumor implantation in the abdominal wall, the tumors continued to grow for approximately 1 week before undergoing regression. This delay before adoptive immunity is expressed is thought to represent the time needed for the passively transferred cells to give rise to a host response of sufficient magnitude to destroy the tumor. None of the mice receiving a similar number of control spleen cells were cured of their sarcomas. Successful therapy was dependent upon the transfer of viable, immune T lymphocytes and required prior irradiation of the tumor-bearing host in order to remove suppressor T cells. Utilizing sequential histologic and immunohistochemical techniques, we attempted to characterize the cellular events of tumor regression. The earliest histologic difference between animals treated with immune and nonimmune lymphocytes was in the number of lymphocytes detected at the perimeter of the tumor in specifically immunized mice on day 6. There was also a striking difference between animals treated with immune versus nonimmune lymphocytes in the intensity and timing of the acute inflammatory response beginning on day 8. The "front" of immunologically mediated tumor destruction appeared at the lateral and deep borders of the implanted sarcomas and progressed inward. During the period of active tumor regression T lymphocytes reactive with a biotinylated mouse anti-Thy 1.2 monoclonal antibody were increased in frozen sections of tumors in mice receiving immune cells relative to the controls. During the first 3 weeks following adoptive transfer of lymphocytes, T cells reactive with Lyt-1 biotinylated mouse monoclonal antibody (helper/inducer phenotype) outnumbered their Lyt-2 (suppressor/cytotoxic) counterparts in frozen sections of tumor from both specifically immunized and control mice. By the end of the 4th week of the experiment, the sarcomas were completely eradicated in all mice receiving immune cells. The previous tumor beds were occupied by collections of lipid-laden macrophages, lymphocytes, plasma cells, and fibroblasts. Despite vigorous but delayed acute and chronic inflammatory responses at the tumor perimeters in the control mice, these tumors all progressed.(ABSTRACT TRUNCATED AT 400 WORDS)

Eradication of a disseminated syngeneic mouse lymphoma by systemic adoptive transfer of immune lymphocytes and its dependence upon a host component(s)

We have studied the in vivo effects of carrageenan and trypan blue on the adoptive immunotherapy of an established local and disseminated syngeneic mouse FBL-3 lymphoma. Mice receiving 500 rads total-body irradiation before injection of FBL-3 tumor into the footpad were treated 4 to 5 days later when a palpable local tumor and disseminated metastases were present. Injection of in vivo immune lymphocytes i.v. caused complete regression of footpad tumor and cured 96% of all mice (greater than 60 days mean survival; p less than 0.0005). Carrageenan or trypan blue treatment of the tumor-bearing host abrogated the therapeutic effect of adoptively transferred cells. Cure rates were significantly reduced to 27% (p less than 0.004) and 0% (p less than 0.0001) and mean survival times to 40.2 days (p less than 0.0005) and 15.2 (p less than 0.005) days for mice treated with carrageenan and trypan blue, respectively, in addition to immune cells. In vivo treatment of the immune spleen cell donors with carrageenan or trypan blue had no significant effect on the ability of those splenocytes to mediate cure when adoptively transferred into tumor-bearing hosts, indicating that the inhibitory activity of these agents cannot be attributed to direct toxicity to immune lymphoid cells. These results demonstrate that a recipient component(s), possibly macrophages, sensitive to carrageenan and to trypan blue but relatively resistant to radiation (500 rads), plays a vital role in the cure of tumor-bearing mice that receive the adoptive transfer of immune splenocytes.

Lymphokine-activated killer cells: lysis of fresh syngeneic natural killer-resistant murine tumor cells by lymphocytes cultured in interleukin 2

Normal splenocytes that are cultured in the lymphokine, interleukin 2 (IL-2), for as short as 2 days develop lytic activity for fresh syngeneic natural killer-resistant tumor cells as well as natural killer-sensitive YAC cells in a 4-hr 51Cr release assay. Lymphokine-activated killer (LAK) cells do not lyse syngeneic fresh lymphocytes but do lyse syngeneic concanavalin A-induced lymphocyte blasts. Lysis is not due to the presence of lectin or xenogeneic serum and appears to be an intrinsic property of lymphocytes activated in IL-2. The activation appears universal in that lymphocytes from all strains of mice activated in this manner exhibited similar patterns of lysis for fresh tumor target cells. To characterize the cells responsible for this lysis, we analyzed the phenotypic expression of surface markers on these cells with depletion techniques using monoclonal antibody and complement. These studies indicate that the precursor of the LAK cell is Thy-1+ and nonadherent to plastic or nylon wool. Lysis of syngeneic tumor was inhibited when LAK cells were treated with an anti-Thy-1.2, or anti-Lyt-2.2 monoclonal antibody and complement but not with anti-Lyt-1.2 monoclonal antibody and complement, indicating that the observed lytic activity was due to a Thy-1+ Lyt-1-2+ cell. Furthermore, LAK cell-mediated lysis could be inhibited by the addition of anti-Lyt-2 or LFA-1 monoclonal antibody to cytotoxicity assays. Cold target inhibition analysis revealed that the syngeneic tumor cells were lysed by recognition of a determinant not present on normal lymphocytes or lymphocyte blasts. This lysis of fresh solid tumor cells by lymphoid cells grown in IL-2 may be of value in the study of tumor-host immunological interactions. The biological significance of tumor lysis by IL-2-activated cells requires further study.

Generation of lytic and proliferative lymphoid clones to syngeneic tumor: in vitro and in vivo studies

T-cell clones that exhibited both lytic and proliferative activity for the syngeneic FBL-3 lymphoma were isolated from in vitro sensitization cultures. These clones were Lyt-2+ and proliferated specifically to the FBL-3 lymphoma but not to other tumors of C57BL/6 origin, allogeneic tumor, or C57BL/6 normal lymphocytes. Adoptive transfer of clones exhibiting both proliferative and cytotoxic activity prolonged survival and occasionally cured the animals of disseminated FBL-3 lymphomas, while T-cell clones exhibiting lytic but no proliferative activity conferred no survival benefit compared to the survival seen among animals receiving no treatment.

In vivo administration of purified Jurkat-derived interleukin 2 in mice

Pure human interleukin 2 (IL-2), produced by the T-cell lymphoma Jurkat, was injected in mice to study the serum half-life, toxicity, and in vivo immunological effects of IL-2. The serum half-life (t1/2) of Jurkat IL-2 in mice appeared to have two components: (a) a rapid initial phase with t1/2 of approximately 2 min during which most of the exogenous IL-2 was cleared from the serum; and (b) a second, slower component with t1/2 of about 9 min. Mice given injections i.p. or i.v. with pure Jurkat IL-2, at doses comparable on a microgram/kg basis to contemplated doses for humans, showed no signs of toxicity on the basis of serial measurements of weight, serum liver and kidney chemistries, or histology of lymphoid and vital organs. Jurkat IL-2 had no effect on the rate of growth or survival of mice with an established s.c. methylcholanthrene-induced fibrosarcoma, but Jurkat IL-2 used in conjunction with in vitro-resensitized and IL-2-expanded specific immune splenocytes prolonged survival of mice with disseminated FBL-3 tumor. This survival prolongation was highly significant when compared to treatment with Jurkat IL-2 alone (p = less than 0.001) or an equivalent number of in vitro-resensitized and expanded cells alone (p = 0.004). Treatment of mice with i.p. Jurkat IL-2 subsequent to secondary immunization with allogeneic tumor enhanced by more than 5-fold the splenocyte cytotoxicity for alloantigen measured 7 days later. Thus, purified human IL-2 derived from the Jurkat cell line has a short half-life in mice with no apparent toxicity at large doses. In vivo efficacy of human IL-2 was demonstrated in increasing alloantigen responsiveness and in increasing the efficacy of transferred expanded immune lymphocytes in the FBL-3 lymphoma model.

Adoptive immunotherapy of established syngeneic solid tumors: role of T lymphoid subpopulations

We have investigated the subpopulations of T cells necessary to mediate the cure of established tumors in two models of successful adoptive immunotherapy. In C57BL/6 mice bearing palpable and disseminated FBL-3 lymphoma, both Lyt-1+ and Lyt-2+ cells played a major role in mediating the regression and permanent cure of mice, whereas in BALB/c mice bearing the Meth A sarcoma the adoptive transfer of Lyt-1+2+ cells played a major role in mediating the regression of tumors and the curing of disease. Identical experiments performed in hybrid (BALB/c X C57BL/6) mice yielded similar results, further supporting our initial observation and indicating that in these two adoptive transfer model systems it is the tumor and not the variable expression of Lyt antigens by the host that determines which T cell subpopulation is required to cure mice of tumors.

The systemic administration of purified interleukin 2 enhances the ability of sensitized murine lymphocytes to cure a disseminated syngeneic lymphoma

Significant serum titers of interleukin 2 (IL 2) can be maintained in mice for 12 h after i.p. injection in a 15% gelatin solution. We have tested the ability of IL 2 administered systemically in this fashion to enhance the therapeutic effect of adoptively transferred specifically sensitized lymphoid cells that were expanded in IL 2. Mice with established local and disseminated FBL-3 lymphoma, induced by intrafootpad injection of 10(7) cells after 500 rad total body irradiation, were treated with a combination of i.v. injected murine splenocytes and either murine supernatants containing IL 2 or pure human IL 2 in gelatin. Splenocytes from immune mice were resensitized to irradiated tumor in vitro and were expanded for 7 days in lectin-free IL 2 supernatants. Treatment with these murine splenocytes administered with murine IL 2 supernatants prolonged mean survival to 33.6 days compared with mean survival times of 16.9 days (p less than 0.001) and 23.4 days (p = 0.007) for mice treated with IL 2 alone or splenocytes alone. Human IL 2, purified to homogeneity from the Jurkat cell line, was also capable of improving the therapeutic efficacy of transferred cells in mice. Mean survival was significantly prolonged to 32.1 days when cells and purified human IL 2 were administered, whereas mean survival times of 18.1 days (p = less than 0.001) and 21.5 (p = less than 0.001) were seen for mice treated with IL 2 alone or expanded immune cells alone. Cure rates in this model were also significantly enhanced with the combined treatment of IL 2 and expanded immune cells. Combined immunotherapy utilizing IL 2 and immune cells was thus significantly better than either component used alone. The systemic administration of IL 2 in conjunction with sensitized expanded lymphoid cells may be a useful approach to the immunotherapy of other murine and human tumors.

The systemic administration of purified interleukin 2 enhances the ability of sensitized murine lymphocytes to cure a disseminated syngeneic lymphoma

Significant serum titers of interleukin 2 (IL 2) can be maintained in mice for 12 h after i.p. injection in a 15% gelatin solution. We have tested the ability of IL 2 administered systemically in this fashion to enhance the therapeutic effect of adoptively transferred specifically sensitized lymphoid cells that were expanded in IL 2. Mice with established local and disseminated FBL-3 lymphoma, induced by intrafootpad injection of 10(7) cells after 500 rad total body irradiation, were treated with a combination of i.v. injected murine splenocytes and either murine supernatants containing IL 2 or pure human IL 2 in gelatin. Splenocytes from immune mice were resensitized to irradiated tumor in vitro and were expanded for 7 days in lectin-free IL 2 supernatants. Treatment with these murine splenocytes administered with murine IL 2 supernatants prolonged mean survival to 33.6 days compared with mean survival times of 16.9 days (p less than 0.001) and 23.4 days (p = 0.007) for mice treated with IL 2 alone or splenocytes alone. Human IL 2, purified to homogeneity from the Jurkat cell line, was also capable of improving the therapeutic efficacy of transferred cells in mice. Mean survival was significantly prolonged to 32.1 days when cells and purified human IL 2 were administered, whereas mean survival times of 18.1 days (p = less than 0.001) and 21.5 (p = less than 0.001) were seen for mice treated with IL 2 alone or expanded immune cells alone. Cure rates in this model were also significantly enhanced with the combined treatment of IL 2 and expanded immune cells. Combined immunotherapy utilizing IL 2 and immune cells was thus significantly better than either component used alone. The systemic administration of IL 2 in conjunction with sensitized expanded lymphoid cells may be a useful approach to the immunotherapy of other murine and human tumors.

Adoptive immunotherapy of established syngeneic solid tumors: role of T lymphoid subpopulations

We have investigated the subpopulations of T cells necessary to mediate the cure of established tumors in two models of successful adoptive immunotherapy. In C57BL/6 mice bearing palpable and disseminated FBL-3 lymphoma, both Lyt-1+ and Lyt-2+ cells played a major role in mediating the regression and permanent cure of mice, whereas in BALB/c mice bearing the Meth A sarcoma the adoptive transfer of Lyt-1+2+ cells played a major role in mediating the regression of tumors and the curing of disease. Identical experiments performed in hybrid (BALB/c X C57BL/6) mice yielded similar results, further supporting our initial observation and indicating that in these two adoptive transfer model systems it is the tumor and not the variable expression of Lyt antigens by the host that determines which T cell subpopulation is required to cure mice of tumors.

Lysis of fresh natural killer-resistant tumor cells by lectin-activated syngeneic and allogeneic murine splenocytes

This paper demonstrates that lectin-activated lymphocytes of selected mouse strains can lyse fresh autologous or allogeneic tumor cells but not the fresh normal cells tested in short-term 51Cr release assays. Murine splenocytes, incubated with concanavalin A for 3 days, lysed tumor cells from fresh syngeneic P815 mastocytoma, 102 methylcholanthrene sarcoma, and FBL3 lymphoma; fresh allogeneic 3LL lung carcinoma and MethA sarcoma; and tissue-cultured YAK cells in 18-hr51Cr release assays. Natural killer cells in fresh splenocyte preparations only lysed tissue-cultured YAK cells and not the other targets. Syngeneic and allogeneic lymphoblasts, lung, or liver cells were not lysed by the concanavalin A-activated killer (CAK) cells. The induction of cytotoxicity by concanavalin A incubation was abrogated by alpha-methylmannoside in the 3-day incubation, but not in cytotoxicity assay. Radiosensitive cells and adherent cells were necessary for the generation of CAK cells. The CAK effectors themselves were radioresistant, nonadherent, and mostly Thy 1+ and Ly 2+. The CAK phenomenon may be mediated by lymphokine production by an Ly 1+ cell, since depletion of Ly 1+ cells prior to activation abrogates CAK induction, and the ability of numerous mouse strains (and nude mice) to generate CAK cells correlated with their ability to produce Interleukin 2. The biological and therapeutic role of these cells is currently being investigated in murine syngeneic primary and metastatic tumor models.

Clonal analysis of the lymphoid cells mediating skin allograft rejection. Mediation of graft rejection in vivo by cloned Lyt-1+2- proliferative, noncytotoxic long-term cell lines

Studies were undertaken to elucidate the cellular basis of skin allograft rejection mediated by long-term cultured cell lines and clones. The adoptive transfer, in vivo, of in-vitro-sensitized cells, from B6AF1 anti B10.BR or from C57BL/6 anti DBA/2 cultures, and expanded eight-fold to ten-fold for one week in lectin-free interleukin 2 (LF-IL-2) were able to mediate specific skin allograft rejection. These same cells lost the ability to mediate accelerated skin graft rejection when they were expanded more than 100-fold during three weeks of culture in LF-IL-2 even though these cultures mediated high levels of specific in vitro cytotoxicity for the appropriate allosensitizing cells. When Lyt-2+ cells were depleted using monoclonal antibodies and complement prior to in vitro sensitization and expansion in LF-IL-2, these cells lines retained the ability to mediate skin allograft rejection in vivo when expanded more than 100-fold for three culture generations in vitro. These latter lines were greatly enriched for Lyt-1+2- cells and had little or no cytolytic activity, but they retained specific in vitro proliferative responses to the sensitizing alloantigen. Several Lyt-1-2+ cloned long-term lymphoid cell lines with high levels of specific cytolytic activity against the sensitizing alloantigen were derived and none was capable of mediating the accelerated rejection of skin grafts in vivo. However, cloned lymphoid cell lines that were phenotypically Lyt-1+2- and were capable of proliferating when in contact with specific alloantigen, but were not cytolytic, were capable of mediating the accelerated rejection of skin grafts in vivo both in irradiated mice and in nude mice. These studies demonstrate that skin allograft rejection can be mediated by Lyt-1+2- cell lines with specific in vitro proliferative activity to alloantigen although Lyt-1-2+ cell lines with cytolytic but not proliferative activity to alloantigen in vitro are ineffective in mediating graft rejection in vivo. Specific proliferative activity and no cytolysis appears to be a good in vitro correlate of the in vivo activity of long-term cultured cell lines.

Simplified techniques for the isolation of alloreactive cell lines and clones with specific cytotoxic or proliferative activity

A rapid method is described for the isolation of alloantigen specific proliferative and cytotoxic clones from primary mixed lymphocyte cultures (MLC). To raise cell lines and clones with specific alloantigenic proliferative activity in vitro, responder splenocytes were depleted of Lyt-2+ cells by monoclonal antibody and complement prior to in vitro sensitization. This procedure resulted in cultures highly proliferative to alloantigen with little or no lytic activity after expansion in interleukin-2 (IL-2). Subsequent cloning of lymphocytes from Lyt-1+ enriched allosensitized cultures by limiting dilution led to proliferative clones in extremely high yield, while cloning from nondepleted allosensitized cultures led to cytotoxic clones in high yield. Furthermore, conditions of high antigen and low IL-2 concentration favor the growth of proliferative cells while high IL-2 concentrations favored the growth of cytotoxic cells. These experiments indicate that selection for cytotoxic or proliferative clones may be enhanced by specific depletion of T cell subpopulations and by alteration of culture conditions.

Dose equivalent conversion factors for human organs and tissues from external radiation

The literature contains a number of tabulations of conversion factors that permit the direct computation of dose equivalent to organs and tissues of the human body for exposure from external radiation sources. Notable among these are conversion factors normalized to external field quantities for full body exposure to monoenergetic photons, full body exposure to photons and electrons from specific radionuclides, partial body exposure to X-ray photons and X-ray spectra used in diagnostic medical radiation, and full body exposure to neutrons. This article surveys the current literature and advises the reader on the scope and sources of more extensive data tabulations.

Regression of a disseminated syngeneic solid tumor by systemic transfer of lymphoid cells expanded in interleukin 2

We have studied the ability of immunized lymphoid cells expanded in IL-2 to mediate the cure of mice with localized and disseminated syngeneic lymphoma. Mice received 500 rad total-body irradiation before injection of tumor into the footpad. Mice were treated 5 d later when a palpable local tumor and disseminated metastases were present. Intravenous injection of in vivo immune lymphocytes cured 93% of all mice, significantly better than any control group (P less than 0.0005). Immune cells, secondarily sensitized to the FBL-3 tumor in vitro, also conferred significant survival benefit (P less than 0.005) when injected intravenously, curing 79% of the animals treated. When these in vitro sensitized cells were expanded in IL-2, 8-10-fold over 7 d, 93% of the animals thus treated were cured, (P less than 0.005). When these cells were grown for multiple generations in IL-2 they retained their ability to cure mice (56% cured, P less than 0.01). This is the first demonstration that intravenous injection of sensitized cells grown in long term culture in IL-2 is capable of curing mice of established local and disseminated syngeneic tumor.

Development of long-term cell lines and lymphoid clones reactive against murine and human tumors: a new approach to the adoptive immunotherapy of cancer

We have investigated the use of T-cell growth factor (TCGF) to isolate and grow, in long-term culture, lymphoid cells with immunologic reactivity directed against syngeneic murine and autologous human tumors. Splenocytes from mice immune to a methylcholanthrene-induced sarcoma were expanded in TCGF, both before and after in vitro mixed lymphocyte-tumor cultures, and expressed high levels of cytotoxicity for fresh syngeneic solid tumor cells. Cloned lines have been isolated with a high level of specific lysis for the immunizing tumor. Similar studies of cytotoxic reactivity to a syngeneic FBL-3 lymphoma have given rise to long-term cytotoxic cell lines growing in TCGF capable of curing mice with disseminated lymphoma in adoptive transfer studies. Exposure to TCGF, of human peripheral lymphoid cells from cancer-bearing patients, results in the development of cytotoxicity to autologous fresh tumor. We have used clonal analysis by limiting dilution techniques to isolate individual cloned cells with this autologous antitumor reactivity. Infusion to autologous cytotoxic cells expanded 10,000-fold in TCGF and labeled with 111In into three cancer patients resulted in cell localization initially to the lung and subsequently to the liver and spleen. The application of these techniques for the cloning and expansion of antitumor T-lymphoid cells in TCGF has offered a new approach to adoptive immunotherapy.

Generation of long-term T-lymphoid cell lines with specific cytotoxic reactivity for a syngeneic murine lymphoma

The long-term in vitro growth in T-cell growth factor (TCGF) of murine cytotoxic T-lymphoid cells directed against syngeneic tumor antigens was investigated. C57BL/6 mice were immunized to syngeneic FBL-3 lymphoma by two ip injections of irradiated FBL-3 lymphoma cells. Splenocytes from these animals were injected into mice with disseminated lethal FBL-3 tumor. The injection of cyclophosphamide (Cy) plus immunized lymphocytes significantly improved survival with cure of 53% of 38 animals. In comparison, treatment with Cy alone resulted in 0 of 31 cured and treatment with Cy plus unimmunized cells resulted in 0 of 40 cured (P less than 0.0005). These in vivo immunized lymphocytes were reexposed to FBL-3 tumor in vitro for 5 days in lectin-free TCGF (LF-TCGF). Although in vivo and in vitro sensitized lymphocytes exhibited no cytotoxicity toward fresh FBL-3 tumor cells in an 18-hour 51Cr release assay, expansion of appropriately sensitized cells in LF-TCGF resulted in significant lysis of fresh FBL-3 tumor cells. This significant lysis was specific and lysed syngeneic FBL-3 but not syngeneic MCA-103 fresh tumor targets. This maximal specific cytotoxicity was maintained for 2.5 months. A screening assay was developed that permitted rapid identification and isolation of low-frequency cytotoxic clones with reactivity specific for FBL-3 tumor. Several of these cloned cells were grown for almost 3 months with maintenance of high degrees of specific lysis (as much as 4,500 lytic U/10(6) cells). These cytotoxic lines and clones will be of value for the study of tumor-host immunologic interactions and perhaps for use in adoptive immunotherapy.

Adoptive chemoimmunotherapy of a syngeneic murine lymphoma with long-term lymphoid cell lines expanded in T cell growth factor

Recently techniques have been developed for the long-term growth of cytotoxic T-lymphoid cells in vitro with T cell growth factor (TCGF). We have investigated the use of these in vitro-expanded T cells for the immunotherapy of a disseminated syngeneic murine FBL-3 lymphoma. In this model, mice with disseminated tumor were treated on day 5 with 180 mg cytoxan/kg and then 5 h later were given lymphoid cells IP. In vivo-immunized lymphocytes resulted in significantly improved survival in three of three experiments, curing 52% of 38 animals, compared with treatment with cytoxan alone (0 of 31 cured) or cytoxan plus unimmunized cells (0 of 40 cured) (P<0.0005). In vivo-immunized lymphocytes were re-exposed to FBL-3 tumor in vitro for 5 days in complete medium (CM) or lectin-free TCGF (LF-TCGF). Both groups showed significantly improved survival in six of six experiments. Cytoxan cured 17% of 66 animals, while cytoxan plus normal lymphocytes after IVS cured 6% of 47 animals. In vivo-immunized cells resensitized in vitro to FBL-3 in CM or LF-TCGF cured 82% of 50 animals (P<0.001) and 72% of 61 animals (P<0.001), respectively. Cells from in vivo- and in vitro-sensitized lymphocytes exhibited no cytotoxicity in our in vitro 51Cr-release assay; expansion of these cells resulted in significant specific lysis of fresh FBL-3 targets. Adoptive transfer of immune lymphocytes resensitized to FBL-3 tumor in vitro and expanded in LF-TCGF conferred a significant survival benefit (P<0.001, curing 7 of 27 animals) compared with all controls. These expanded cells were then continuously grown in LF-TCGF for 2 1/2 months. Again, in vivo-immunized lymphocytes resensitized to FBL-3 tumor and expanded in LF-TCGF for 2 1/2 months cured 56% of the animals with disseminated tumor, significantly prolonging survival over that recorded in any control group (P<0.0002). Irradiation of these same cells totally abolished their efficacy. Clones were generated from IVS and continuously grown in LF-TCGF. Two of these clones were very cytotoxic for fresh FBL-3 (>4,000 lytic units/106 cells). When adoptively transferred to mice in this chemoimmunotherapy model these cytotoxic clones significantly enhanced survival over that recorded following treatment with cytoxan alone (P<0.00001), though prolongation of survival was small. Implications of these results for application of these techniques to other less antigenic tumors and human cancers are discussed.