Successful granulocyte-colony stimulating factor treatment of Crohn's disease is associated with the appearance of circulating interleukin-10-producing T cells and increased lamina propria plasmacytoid dendritic cells.

Granulocyte-colony stimulating factor (G-CSF) has proved to be a successful therapy for some patients with Crohn's disease. Given the known ability of G-CSF to exert anti-T helper 1 effects and to induce interleukin (IL)-10-secreting regulatory T cells, we studied whether clinical benefit from G-CSF therapy in active Crohn's disease was associated with decreased inflammatory cytokine production and/or increased regulatory responses. Crohn's patients were treated with G-CSF (5 microg/kg/day subcutaneously) for 4 weeks and changes in cell phenotype, cytokine production and dendritic cell subsets were measured in the peripheral blood and colonic mucosal biopsies using flow cytometry, enzyme-linked immunosorbent assay and immunocytochemistry. Crohn's patients who achieved a clinical response or remission based on the decrease in the Crohn's disease activity index differed from non-responding patients in several important ways: at the end of treatment, responding patients had significantly more CD4(+) memory T cells producing IL-10 in the peripheral blood; they also had a greatly enhanced CD123(+) plasmacytoid dendritic cell infiltration of the lamina propria. Interferon-gamma production capacity was not changed significantly except in non-responders, where it increased. These data show that clinical benefit from G-CSF treatment in Crohn's disease is accompanied by significant induction of IL-10 secreting T cells as well as increases in plasmacytoid dendritic cells in the lamina propria of the inflamed gut mucosa.

Parental knowledge and practice of primary skin cancer prevention: gaps and solutions.

Over the past two decades there have been significant efforts in the United States to heighten awareness about skin cancer. Our goal was to assess parental knowledge, practice, and source of information about sun protection for their children. A questionnaire was administered to 158 parents of children at a dermatology clinic and 96 parents of children at a pediatric clinic (n=254). The survey included four parts: demographics, knowledge about skin cancer, sun protection practices, and sources of sun protection information. The mean knowledge score was 61% correct. Independent predictors of a higher score were fewer children and being a health care or other professional (p < 0.03). Independent predictors of parental sunscreen use were higher knowledge score, younger age, and fewer lifetime sunburns (p < 0.03); predictors of sunscreen use for children were higher knowledge score and fairer skin (p < 0.03). The top sources of sun protection information ranked by respondents were television and magazines; the top desired sources were primary care physicians and dermatologists. The knowledge results suggest the need for increased education about skin cancer prevention. Because the media is a major information source, it is important to ensure that messages about sun risks/protection are correct. The respondents' desire to learn more from primary care physicians emphasizes the need to educate physicians about sun protection.

Interactive computer technology for skin cancer prevention targeting children.

BACKGROUND: Computer technology has become an integral part of health care, yet there have been few studies exploring the use of multimedia technology in the prevention of cancer, especially targeting children. OBJECTIVE: The aims of this study were to develop and evaluate a new multimedia computer program for the primary prevention of skin cancer among a childhood population. DESIGN AND PARTICIPANTS: An interactive CD-ROM program was developed, then pilot tested in a public elementary school in rural North Carolina. This intervention trial involved 8 third- and fourth-grade classes (N = 209 students), randomized into 3 groups: computer intervention, standard teacher-led intervention, and controls. MAIN OUTCOME MEASURES: Students were tested using pre- and postintervention surveys that measured knowledge, attitudes, and self-reported behaviors. A 7-month follow-up survey was performed. RESULTS: There was a significant increase in postintervention knowledge for the computer group when compared to either the teacher-led or control groups (mean scores out of 100: 75.2, 59.5, 55.0, respectively; p < 0.001). Attitudes about suntanning demonstrated a significant difference between the 3 groups (mean scores out of 100: 64.0, 53.0, 48.6, respectively; p = 0.002). There were slight improvements in the behavioral scores, especially among the computer group, but the overall differences were not significant. Similar overall results were found for the long-term follow-up survey, except that attitudes about suntanning no longer demonstrated a significant difference. CONCLUSION: These results indicate that this new educational tool is an effective way to introduce health education programs for young children in typical classroom settings. This prototype may serve as a model for the development of future preventive school-based programs, including applications to other conditions associated with high-risk behaviors among children.

Suppression of graft-versus-host disease and amplification of graft-versus-tumor effects by activated natural killer cells after allogeneic bone marrow transplantation.

Bone marrow transplantation (BMT) is currently used for the treatment of a variety of neoplastic diseases. However, significant obstacles limiting the efficacy of allogeneic BMT are the occurrence of graft-versus-host disease (GvHD) and tumor relapse. Natural killer (NK) cells exert a variety of immunologic and homoeostatic functions. We examined whether adoptive transfer of activated NK cells of donor type would prevent GvHD after allogeneic BMT in mice. Lethally irradiated C57BL/6 (H-2(b)) mice, were transplanted with MHC incompatible BALB/c (H-2(d)) bone marrow cells and spleen cells and rapidly succumbed to acute GvHD. In contrast, mice that also received activated NK cells of donor type exhibited significant increases in survival. In determining the mechanism by which the NK cells prevented GvHD, mice were concurrently treated with a neutralizing antibodies to the immunosuppressive cytokine TGFbeta. Anti-TGFbeta completely abrogated the protective effects of the activated donor NK cells indicating that TGFbeta plays an important role in the prevention of GvHD by NK cells. We then examined whether activated NK cells of donor type after allogeneic BMT would induce graft-versus-tumor (GvT) effects without GvHD in mice bearing a murine colon adenocarcinoma (MCA-38). 10 d after receiving the tumor, in which the mice had demonstrable lung metastases, recipients received an allogeneic BMT with or without activated NK cells. Administration of activated NK cells resulted in significant GvT effects after allogeneic BMT as evidenced by increases in median survival and fewer lung metastasis. No evidence of GVHD was detected compared with recipients receiving spleen cells alone which also developed fewer lung metastases but in which all had succumbed to GVHD. Thus, our findings suggest that adoptive immunotherapy using activated donor NK cells combined with allogeneic BMT inhibits GvHD and promotes GvT in advanced tumor-bearing mice. These results also suggest that GvT and GvHD can be dissociable phenomena.

Tumor antigen-specific immunization of bone marrow transplantation donors as adoptive therapy against established tumor.

BACKGROUND: Persistence of the underlying malignancy remains the main obstacle to the successful treatment of human malignancies with high-dose chemoradiotherapy and bone marrow transplantation. PURPOSE: The aim of this study was to determine whether antigen-specific antitumor immune responses, elicited in normal donor mice by immunization with the soluble form of a surrogate tumor antigen (i.e., ovalbumin [OVA]), can be transferred via bone marrow transplantation into lethally irradiated, syngeneic recipient mice. An additional goal was to evaluate the ability of these adoptively transferred bone marrow cells to eradicate established recombinant OVA-expressing lymphomas that recurred after lethal-dose total-body irradiation (TBI). METHODS: Female C57BL/6 donor mice were immunized twice with OVA emulsified in a muramyl-dipeptide-containing adjuvant. Syngeneic mice bearing a day-10 or day-11, approximately 1-cm subcutaneous E.G7-OVA tumor (E.G7-OVA tumor cells were derived from transfection of EL-4 thymoma tumor cells using the coding sequence of chicken OVA gene complementary DNA) were treated with TBI and reconstituted with bone marrow from nonimmune or OVA-immunized mice. In subsequent experiments, tumor-bearing mice, treated with TBI and OVA-immune bone marrow, were given additional therapy either with a single OVA immunization or by the adoptive transfer of 1 x 10(7) in vitro activated spleen cells derived from OVA-immune donor mice and cultured 5 days with irradiated E.G7-OVA cells before transfer. RESULTS: E.G7-OVA tumor-bearing mice given TBI and OVA-immune bone marrow showed a significantly increased cure rate when compared with that among controls reconstituted with nonimmune bone marrow after TBI (logrank, P < .01). The antitumor effect of immune bone marrow was abrogated by T-cell depletion of the marrow graft (P < .016). The antitumor effect of immune marrow was enhanced by the addition of OVA immunization of tumor-bearing recipients (P < .015). OVA-specific cytotoxic T-lymphocyte (CTL) activity was recovered from tumor-bearing recipients of immune marrow 14 days after bone marrow transplantation. The antitumor effect observed following the adoptive transfer of immune marrow was further augmented by the addition of 1 x 10(7) splenic E.G7-OVA-specific in vitro activated CTLs derived from OVA-immune mice (P < .03). CONCLUSION: These studies establish the principle that antigen-specific T-cell immunity against a defined tumor-specific antigen can be transferred with bone marrow from an immune donor. IMPLICATIONS: Active immunization of normal human bone marrow or T-cell donors with a refined, safe tumor antigen and transfer of immunity to the patient may represent a novel strategy for circumventing the obstacle of host immune suppression associated with the tumor-bearing state.

Induction of a CD8+ cytotoxic T lymphocyte response to soluble antigen given together with a novel muramyl dipeptide adjuvant, N-acetyl-D-glucosaminyl-(beta 1-4)-N-acetylmuramyl-L-alanyl-D-isoglutamine (GMDP).

We have investigated the ability of the novel muramyl dipeptide, GMDP, to act as an adjuvant for the induction of ovalbumin (OVA)-specific, CD8+ cytotoxic T lymphocyte (CTL) responses. C57Bl/6 mice were twice immunized s.c. with 50 micrograms OVA emulsified with a squalane, L121 pluronic containing Tween-80 vehicle either with (STP-GMDP) or without (STP) GMDP. Splenic precursor CD8+ CTL activity against E.G7-OVA, but not against EL-4 parental targets was detected in STP-GMDP immunized mice after 5 days of in vitro re-stimulation with irradiated E.G7-OVA cells, while mice immunized with OVA in STP alone or OVA alone failed to demonstrate CTL activity. OVA emulsified in a microfluidized STP vehicle formulation without GMDP also elicited the E.G7-OVA precursor CTL. The ability of GMDP to induce a class I-restricted, CD8+ CTL response to a soluble protein antigen may have implications for the development of useful vaccines against viral pathogens or tumours against which CTL responses are desirable.

Practical approaches to pediatric dermatology.

Pediatric dermatology has evolved as a subspecialty of dermatology. The ability to recognize and adequately treat the most common pediatric dermatoses represents an important skill for all dermatology nurses.

Hematopoietic stem cell depletion by restorative growth factor regimens during repeated high-dose cyclophosphamide therapy.

We studied the effects of six cycles of repeated cyclophosphamide (CTX) therapy followed by restorative therapy with either granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF on the hematopoietic stem cell compartment. Stem cell function was assessed by serially transferring bone marrow cells from CTX-CSF-treated mice into lethally irradiated recipient mice. Bone marrow cells from mice that initially received either G-CSF or GM-CSF after CTX therapy more rapidly lost the ability to repopulate the recipient lymphoid organs, showed a dramatic loss of hematopoietic progenitors, a more rapid loss of CFU-S capacity, and a 40% to 50% reduction in marrow repopulating ability (MRA). Interleukin-1 (IL-1) appeared to have little effect on the CTX-treated mice when used alone. However, when administered before the CTX-CSF regimen, IL-1 prevented the stem cell depletion as determined by CFU-C, CFU-S, and MRA through the serial transplantation procedures. These results support the hypothesis that repeated treatments with myelosuppressive drugs followed by stimulation with the CSFs may induce damage to the host stem cell compartment, and further suggest that pretreatment with IL-1 before CTX therapy may prevent this stem cell damage.

Systemic IL-1 and adjuvant treatment of an experimental tumor. I. Immune status following tumor rechallenge.

Local adjuvant therapy of weakly immunogenic tumors protects against primary tumor challenge. However, this form of therapy does not produce long-lasting immunity to the tumor. In this study, local adjuvant therapy combined with systemic IL-1 administration produced not only primary tumor protection, but also long lasting immunity to the tumor. IL-1 and adjuvant protected animals resisted rechallenge with tumor as much as 180 days after initial tumor administration. Resistance to tumor rechallenge was IL-1 dose dependent. IL-1 and adjuvant protected animals also exhibited delayed type hypersensitivity reactions which were tumor-specific. Splenic and lymph node cell populations from IL-1 and adjuvant protected animals mounted tumor-specific lymphoproliferative responses. No such responses were observed in animals which had been administered either IL-1 or adjuvant alone. These results demonstrate that systemic IL-1 functions to augment specific immune protection when administered in conjunction with local adjuvant, resulting in long-lasting tumor immunity.

Preclinical evaluation of bryostatin as an anticancer agent against several murine tumor cell lines: in vitro versus in vivo activity.

We have examined the ability of bryostatin 1 to inhibit the in vitro growth and in vivo development of a panel of four murine tumors of diverse tissue origins. A wide range of antiproliferative responses was observed for the four tumors. At 100 ng/ml the in vitro growth of the Renca renal adenocarcinoma, the B16 melanoma, the M5076 reticulum cell sarcoma, and the L10A B-cell lymphoma were inhibited by 0, 40, 40, and 94% respectively. All three cell lines sensitive to bryostatin in vitro responded to multiple dose, 1 microgram/injection/day in vivo i.p., bryostatin therapy. Only the in vitro resistant Renca tumor failed to respond to bryostatin in vivo. The correlation between in vitro and in vivo antitumor efficacy suggests a direct mechanism of antitumor activity for bryostatin. Both local regional therapy (M5076 i.p.) and systemic therapy (B16 lung metastases and L10A s.c. tumors) with bryostatin were successful at prolonging survival time. Multiple i.p. doses of bryostatin at a minimum level of 0.5-1.0 microgram/injection were required to observe significant in vivo antitumor effects. The success of in vivo administration of bryostatin in mice bearing 8-10-mm s.c. masses of L10A lymphoma (5-10 x 10(9)) and our further observation that five of a panel of six human B-cell lymphoma cell lines were sensitive to the growth inhibitory effects of bryostatin in vitro suggest that bryostatin may be effective in treating lymphoid malignancies in humans.

Systemic alkalinization inhibits the ability of flavone acetic acid to augment natural killer activity, induce cytokine gene expression, and synergize with interleukin 2 for the treatment of murine renal cancer.

Flavone acetic acid (FAA) is an investigational drug that augments natural killer activity, induces the genes for alpha- and gamma-interferon (IFN) and tumor necrosis factor alpha, and synergizes with recombinant interleukin 2 for the successful treatment of murine renal cancer. However, in most clinical studies of FAA only minimal immunomodulatory effects have been reported. Most of the patients in these studies have also been given sodium bicarbonate to prevent possible nephrotoxicity. The current study was performed to determine whether alkalinization had any effects on FAA-induced immune modulation and therapeutic activity in mice. The results showed that alkalinization inhibited the treatment of murine renal cancer by FAA plus recombinant interleukin 2 such that the survival rate of 84% in nonalkalinized mice was reduced to 0 in mice that were alkalinized during treatment. Alkalinization also significantly inhibited the ability of FAA to augment both splenic and hepatic natural killer activity in a dose-dependent manner. In contrast, alkalinization did not inhibit the ability of polyinosinic:polycytidylic acid and poly-L-lysine stabilized in carboxymethyl cellulose, maleic anhydride divinyl ether, or Propionibacterium acnes to augment liver-associated natural killer activity. By Northern blot analysis, it was shown that the induction of mRNA for IFN-alpha, IFN-gamma, and tumor necrosis factor alpha by FAA in the spleen cells of mice was significantly reduced in alkalinized mice. Consistent with a reduction in the FAA-induced expression of the cytokine genes, alkalinization also resulted in a significant decrease in both the peak serum concentration and duration of detectable IFN activity following FAA treatment. Increasing the dose of FAA in alkalinized mice to 300 mg/kg overcame the deleterious effects of alkalinization for treatment of murine renal cancer by FAA plus recombinant interleukin 2. These results demonstrate that the process of alkalinization inhibits the immunomodulatory and immunotherapeutic effects of FAA in mice and suggest that alkalinization might have similar deleterious effects on FAA-induced immune stimulation in human clinical trials.

Correlation between in vivo induction of cytokine gene expression by flavone acetic acid and strict dose dependency and therapeutic efficacy against murine renal cancer.

The investigational chemotherapeutic drug flavone acetic acid (FAA) acts as an immunomodulator by augmenting natural killer activity in both humans and rodents after in vivo administration. The accumulated data derived from a series of experiments also demonstrates that FAA synergizes with interleukin 2 (IL-2) for the treatment of murine renal cancer. The immunomodulatory and immunotherapeutic effects of FAA are strictly dose dependent with doses of FAA greater than 150 mg/kg effectively synergizing with IL-2, and doses less than 150 mg/kg exhibiting very little therapeutic effect. The antitumor and immunomodulatory effects of FAA are more pronounced in vivo than in vitro. Collectively, these results suggested that cytokines induced by FAA may contribute to these effects, and that the induction of such cytokines may also be very dose dependent. Studies were therefore initiated to investigate whether the in vivo administration of FAA would alter the expression of cytokine mRNA in leukocytes. Splenic leukocytes or liver nonparenchymal cells from untreated and FAA-treated mice were used as a source of RNA for Northern blot analysis. Interferon alpha and interferon gamma mRNA in the spleen was upregulated within 1.5 h after FAA administration, with peak induction occurring by about 2 h. An upregulation of tumor necrosis factor alpha mRNA was detected in the spleen by 0.5-1 h after treatment with peak induction occurring by 1-1.5 h. Induction of tumor necrosis factor alpha mRNA was also detected in hepatic nonparenchymal cells. No up-regulation of splenic mRNA for tumor necrosis factor beta, IL-1 alpha or beta, or IL-2 was detected after FAA administration. IFN and TNF activities were detectable in the serum by bioassay immediately following the appearance of mRNA in FAA mice. The observed up-regulation by FAA of cytokine mRNA and the corresponding serum protein was strictly dose dependent with substantial induction of both mRNA and proteins occurring only at FAA doses greater than or equal to 150 mg/kg, a dose range also shown to be the minimum required for immunomodulatory and immunotherapeutic effects. In summary, these results demonstrate that FAA acts as a potent inducer of at least three cytokines in vivo, and suggest that the immunomodulatory and immunotherapeutic effects of FAA may be partially mediated by these induced cytokines.

Augmentation of natural killer activity, induction of IFN and development tumor immunity during the successful treatment of established murine renal cancer using flavone acetic acid and IL-2.

The investigational drug flavone acetic acid (FAA) has been previously shown to systemically augment NK activity in vivo in normal mice within 24 h of i.p. or i.v. administration. The current study investigates the ability of FAA, and/or rIL-2, to augment NK activity and antitumor responses in mice bearing murine renal cancer (Renca). The results demonstrate that FAA potently augments NK activity in the blood, spleen, and liver of Renca-bearing mice and that the administration of rIL-2 in addition to FAA results in a further augmentation of NK activity over that observed with FAA alone. Renca-bearing mice treated with FAA (200 to 250 mg/kg) plus rIL-2 exhibited a significantly increased incidence of long term survivors (59%) over that observed following treatment with FAA (0%) or rIL-2 (5%) alone. Therapeutic synergy between FAA and rIL-2 was observed against primary tumors, minimal residual disease, and experimental-induced pulmonary metastases. Mice cured of Renca by FAA plus rIL-2 treatment were largely resistant to rechallenge with Renca suggesting a role for T lymphocytes. The augmentation of NK activity and the therapeutic effects of FAA coincided with the rapid induction of high titers of serum IFN of the alpha/beta type within 4 h of FAA administration. Subsequent studies demonstrated that the contribution of FAA could be partially replaced by the administration of several doses of human rIFN-alpha A/D Bg1 before the initiation of rIL-2 administration. The observed synergistic antitumor effects of FAA plus rIL-2 coincided with the augmentation of NK activity, induction of IFN-alpha/beta, and induction of long lasting tumor immunity. Overall, these results suggest that this approach may obviate the need for adoptive immunotherapy in association with rIL-2 administration for at least some tumor types.

Immunomodulation of natural killer cell activity by flavone acetic acid: occurrence via induction of interferon alpha/beta.

The investigational drug flavone acetic acid (FAA) systemically augments natural killer (NK) cell activity in normal and tumor-bearing mice and in human cancer patients. The results from the present investigation demonstrate that in vivo administration of FAA induces in a dose-dependent manner high levels of serum interferon (IFN) within 4 hours in BALB/c, C57BL/6, and BALB/c nude mice. Antibody neutralization studies indicated that FAA induced IFN of the alpha/beta type, while molecular hybridization studies demonstrated that FAA rapidly stimulated the production of IFN alpha mRNA in splenic leukocytes. In vivo administration of anti-IFN alpha/beta antibodies to FAA-treated mice inhibited the FAA-induced augmentation of splenic NK cell activity at 4 hours. These results suggest that FAA mediates its anti-tumor effects indirectly by immunomodulation as well as directly by antiproliferative or cytotoxic activity.

Flavone-8-acetic acid augments systemic natural killer cell activity and synergizes with IL-2 for treatment of murine renal cancer.

The investigational drug flavone-8-acetic acid (FAA) potently augments NK activity in the spleen, liver, lungs, and peritoneum in a dose-dependent manner after i.v. or i.p. administration. Augmented NK activity peaks by 24 h after FAA injection and returns to normal after 6 days. Combined treatment of established murine renal cancer with FAA and rIL-2 results in up to 80% long term survival whereas FAA or rIL-2 alone were unable to induce any long term survivors. The optimal dose of rIL-2 required for use with FAA was in the range of 10,000 to 30,000 U/day. Further studies demonstrated that the regimen of FAA plus rIL-2 administration that was effective in treating established murine renal cancer also induced a more potent augmentation of NK activity than did either FAA or rIL-2 alone. Subsequent studies revealed that the therapeutic effectiveness of FAA plus rIL-2 was significantly reduced when tumor-bearing mice were treated with anti-asialo GM1 serum. These results are consistent with a role for augmented NK activity in the therapeutic effects of FAA plus rIL-2 murine renal cancer. In addition, these studies demonstrate that FAA and rIL-2 is a useful approach for cancer treatment in that subtoxic doses of rIL-2 can be used and significant anti-tumor efficacy occurs even without accompanying adoptive immunotherapy.