Lymphokine-activated Killer Research Articles

Highly Enhanced Cytotoxicity of a Dimeric Bispecific Diabody, the hEx3 Tetrabody

We previously reported the utility for cancer immunotherapy of a humanized bispecific diabody (hEx3) that targets epidermal growth factor receptor and CD3. Here, we used dynamic and static light scattering measurements to show that the multimer fraction observed in hEx3 in solution is a monodisperse tetramer. The multimerization into tetramers increased the inhibition of cancer cell growth by the hEx3 diabody. Furthermore, 1:2 stoichiometric binding for both antigens was observed in a thermodynamic analysis, indicating that the tetramer has bivalent binding activity for each target, and the structure may be in a circular configuration, as is the case for the single-chain Fv tetrabody. In addition to enhanced cytotoxicity, the functional affinity and stability of the hEx3 tetrabody were superior to those of the hEx3 diabody. The increase in molecular weight is also expected to improve the pharmacokinetics of the bispecific diabody, making the hEx3 tetrabody attractive as a therapeutic antibody fragment for cancer immunotherapy.

Cytotoxic drugs up-regulate epidermal growth factor receptor (EGFR) expression in colon cancer cells and enhance their susceptibility to EGFR-targeted antibody-dependent cell-mediated-cytotoxicity (ADCC)

Cetuximab is a human–murine chimeric IgG1 monoclonal antibody to epidermal growth factor-receptor (EGFR) which exerts synergistic antitumour interactions with several cytotoxic drugs. Therefore, it is presently recommended in combination with chemotherapy in the treatment of colon, head and neck and non-small cell lung cancer. Cetuximab has been designed to inhibit EGFR signalling; however, preclinical evidence suggests that its anti-cancer effects in vivo are also related to the ability of its human IgG1 backbone to trigger immunological mechanisms. Here we have investigated whether the exposure to different cytotoxic drugs may affect the susceptibility of colon cancer cells in vitro to cetuximab immuno-targeting and related lymphokine-activated killer (LAK)-mediated antibody-dependent cell cytotoxicity (ADCC). Five colon cancer cell lines expressing a different k-ras mutational status were evaluated for: (i) EGFR-expression, (ii) susceptibility to LAK cells and (iii) cetuximab-mediated ADCC, before and after exposure to 5-flurouracil (5-FU), gemcitabine (Gem), irinotecan (Iri) alone or in multiple two/three drug combinations. These drugs were able to up-regulate EGFR expression on the surface of all the colon cancer cell lines with a maximal effect observed few hours after the exposure to GILF regimen (Gem, Iri, Levofolinic acid and 5-FU). Chemotherapy was able to greatly enhance the sensitivity to either LAK cells or cetuximab-mediated ADCC in all the colon cancer cell lines with a mechanism independent from k-ras status. The results of our study suggest that chemotherapy may enhance cetuximab-mediated immuno-targeting and ADCC thus providing the rationale to design novel immuno-biochemotherapy regimens.

Abstract 5304: Serum vascular endothelial growth factor in advanced breast cancer patients might be a key role of inhibitory effect on lymphokine activated killer cells

Abstract Previously, we reported that serum from stage IV breast cancer patients diminished the cytotoxic activity of lymphokine activated killer cells (LAKs) (Abstract #4639 AACR in 2008). Thus, we next tested what the critical role for the inhibitory effect on LAKs was. Based on the study of protein detection in the serum using Cytokine Antibody Array (Ray Biotech), serum from stage IV patients seemed to have higher level of vascular endothelial growth factor (VEGF) as compared to early stage patients. To confirm this by more accurate way, we analyzed the serum level of VEGF by using ELISA in 24 breast cancer patients. When the serum level of VEGF was cut off by median (420 pg/ml), 11 patients with higher level of VEGF out of 12 are included in the patients whose serum inhibited the cyototoxic activity of LAKs. Therefore, we hypothesized that VEGF might be one of the key role for inhibitory effect on LAKs and neutralization of serum VEGF from the patients whose serum inhibited the cyototoxic activity of LAKs could have no inhibitory effect on LAKs. Briefly, PBMCs from a healthy volunteer were used as an effector cell for all patients’ serum incubation. After activation of the PBMCs using IL-2, LAKs were prepared and incubated with the individual patient's serum and washed. The LAKs were incubated with human breast cancer cell line MCF-7 as a target cell and LDH assay was performed to detect cytotoxicity of the LAKs. Fourteen out of 24 patients serum (serum 1) showed inhibitory effect on LAKs and we picked up these patients to test blocking study of serum VEGF. Briefly, serum from these 14 patients was incubated with neutralization antibody of VEGF (R16Y, Santa Cruz Biotechnology) (serum 2) before mix with LAKs. After incubation of serum 1 and serum 2 with LAKs, target cell cytotoxicity of LAKs from incubation with serum 1 showed 30-50% reduced level as compared to control LAKs activity. Interestingly, target cell cytotoxicity of all LAKs from incubation with serum 2 did not show such inhibitory effect (mean cell cytotoxicity of LAKs was 33.48% and 57.27%, serum 1 and serum 2, respectively, control; 55.73%). These data suggest that high level of serum VEGF in breast cancer patients might be a key role of inhibitory effect on LAKs and neutralization of the VEGF could help adoptively transferred LAKs as cancer immunotherapy in the patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5304.

Number of Treatment Cycles Influences Development of Cytotoxic T Cells in Metastatic Breast Cancer Patients – A Phase I/II Study

The influence of the number of apheresis-stimulation-infusion(s) cycles, and the time in culture before the infusion (one vs. two weeks), on the generation of tumor antigen-specific cytotoxic T-lymphocytes (CTL) was investigated in a phase I/II clinical adoptive immunotherapy trial. Two previously treated metastatic breast cancer patients with no evidence of disease, in complete remission (CR), were enrolled. Each apheretic peripheral blood mononuclear cell (PBMC) sample was stimulated twice with MUC-1 before infusion back into the patients. Killer T-cells responses against MUC-1-expressing MCF-7 (CTL), nonspecific natural killer (NK) and lymphokine-activated killer (LAK) target cell lines, as well as, cytokine production were measured before each infusion. Patients received 2 infusions per month for 4 months. There were no tumor recurrences or toxicity. CTL, NK and LAK cells, type 1 cytokine, gamma-interferon (G-INF), and CD4+ and CD8+ memory T-lymphocytes were initially generated, produced or induced, respectively, and then declined. The CTL, NK and LAK cells were only induced at the first infusion of the first month. Thus, maintaining PBMC in culture longer than the first infusion was of no benefit with regards to retaining functional killer T-cells. In conclusion, this study implies that one treatment is optimal.

Overview of Cellular Immunotherapy for Patients with Glioblastoma

High grade gliomas (HGG) including glioblastomas (GBM) are the most common and devastating primary brain tumours. Despite important progresses in GBM treatment that currently includes surgery combined to radio- and chemotherapy, GBM patients' prognosis remains very poor. Immunotherapy is one of the new promising therapeutic approaches that can specifically target tumour cells. Such an approach could also maintain long term antitumour responses without inducing neurologic defects. Since the past 25 years, adoptive and active immunotherapies using lymphokine-activated killer cells, cytotoxic T cells, tumour-infiltrating lymphocytes, autologous tumour cells, and dendritic cells have been tested in phase I/II clinical trials with HGG patients. This paper inventories these cellular immunotherapeutic strategies and discusses their efficacy, limits, and future perspectives for optimizing the treatment to achieve clinical benefits for GBM patients.

Alterations in the Th1/Th2 balance in breast cancer patients using reflexology and scalp massage

The diagnosis and treatment of breast cancer can adversely affect quality of life. Here the aim was to determine the effects of reflexology on host defences and endocrine function in women with early breast cancer. Six weeks after surgery for early breast cancer, 183 women were randomly assigned to self-initiated support (SIS), SIS plus foot reflexology, or SIS plus scalp massage. Peripheral blood mononuclear cells and serum were isolated at T1 (6 weeks post surgery; baseline), T2 and T3 (4 and 10 weeks post completion of intervention, respectively). Lymphocyte phenotyping found that CD25(+) cells were significantly higher in the massage group compared with the SIS group at T3. The percentage of T cells, and more specifically the T helper subset expressing IL4, decreased significantly in the massage group compared with the SIS group at T3. This change was accompanied by an increase in the percentage of CD8(+) T cytotoxic cells expressing IFNγ in the massage group. Natural killer and lymphokine activated killer cell cytotoxicity measurements, serum levels of cortisol, prolactin and growth hormone, and flow cytometric assessment of their corresponding receptors all revealed no significant differences between the three groups of patients. This study provides evidence that the immunological balance of patients can be altered in a potentially beneficial manner by massage. The original trial was registered with the International Standard Randomised Controlled Trial Registry (ISRCTN87652313).

Posttransplant Lymphoproliferative Disorder Following Kidney Transplant

Posttransplant Lymphoproliferative Disorder Following Kidney Transplant

Alterations in the Th1/Th2 balance in breast cancer patients using reflexology and scalp massage

The diagnosis and treatment of breast cancer can adversely affect quality of life. Here the aim was to determine the effects of reflexology on host defences and endocrine function in women with early breast cancer. Six weeks after surgery for early breast cancer, 183 women were randomly assigned to self-initiated support (SIS), SIS plus foot reflexology, or SIS plus scalp massage. Peripheral blood mononuclear cells and serum were isolated at T1 (6 weeks post surgery; baseline), T2 and T3 (4 and 10 weeks post completion of intervention, respectively). Lymphocyte phenotyping found that CD25+ cells were significantly higher in the massage group compared with the SIS group at T3. The percentage of T cells, and more specifically the T helper subset expressing IL4, decreased significantly in the massage group compared with the SIS group at T3. This change was accompanied by an increase in the percentage of CD8+ T cytotoxic cells expressing IFNγ in the massage group. Natural killer and lymphokine activated killer cell cytotoxicity measurements, serum levels of cortisol, prolactin and growth hormone, and flow cytometric assessment of their corresponding receptors all revealed no significant differences between the three groups of patients. This study provides evidence that the immunological balance of patients can be altered in a potentially beneficial manner by massage. The original trial was registered with the International Standard Randomised Controlled Trial Registry (ISRCTN87652313).

Intralesional Lymphokine-activated Killer Cells as Adjuvant Therapy for Primary Glioblastoma

Despite recent advances, median survival for patients with resectable glioblastoma multiforme (GBM) is only 12 to 15 months. We previously observed minimal toxicity and a 9.0-month median survival after treatment with intralesional autologous lymphokine-activated killer (LAK) cells in 40 patients with recurrent GBM. In this study, GBM patients were treated with adjuvant intralesional LAK cells. Eligible patients had completed primary therapy for GBM without disease progression. LAK cells were produced by incubating autologous peripheral blood mononuclear cells with interleukin-2 for 3 to 7 days and then placed into the surgically exposed tumor cavity by a neurosurgeon. The 19 men and 14 women had a median age of 57 years. Prior therapy included surgical resection (97%), partial brain irradiation (97%), gamma knife radiosurgery (97%), and temozolomide chemotherapy (70%). Median time from diagnosis to LAK cell therapy was 5.3 months (range: 3.0 to 11.1 mo). LAK cell treatment was well tolerated; average length of hospitalization was 3 days. At the time of this analysis, 27 patients have died; the median survival from the date of original diagnosis is 20.5 months with a 1-year survival rate of 75%. In subset analyses, superior survival was observed for patients who received higher numbers of CD3+/CD16+/CD56+ (T-LAK) cells in the cell products, which was associated with not taking corticosteroids in the month before leukopheresis. Intralesional LAK cell therapy is safe and the survival sufficiently encouraging to warrant further evaluation in a randomized phase 2 trial of intralesional therapies with LAK or carmustine-impregnated wafers.

Personalized immunotherapy: a siren myth?

10.2217/PME.09.39 © 2009 Future Medicine Ltd “...the antigenic characteristics of tumor cells can be perceived by the innate and cognate immune systems, which represent the extrinsic barriers against tumor progression, or at least a substantial component of the host–tumor equilibrium.” Antoine Tesniere1,2,3 1U848 INSERM, ‘Cancer, Apoptosis & Immunity, Villejuif, France 2Institut Gustave Roussy, Villejuif, France 3Universite Paris Sud, Villejuif, France Guido Kroemer1,2,3 1U848 INSERM, ‘Cancer, Apoptosis & Immunity, Villejuif, France 2Institut Gustave Roussy, Villejuif, France 3Universite Paris Sud, Villejuif, France Thomas Tursz Departement de medecine, Institut Gustave Roussy, Villejuif, France

Chronic antidepressant treatment exerts sexually dimorphic immunomodulatory effects in an experimental model of major depression: do females lack an advantage?

Major depression is a stress-related disorder that affects about 20% of the population, with women outnumbering men by 2:1. However, research focusing on stress/antidepressant-related immunomodulation overlooks sex differences, although an established sexual dimorphism also characterizes the immune system. We report for the first time that both chronic clomipramine treatment (10 mg/kg, twice daily) and chronic mild stress (CMS) application in rats, exert sexually dimorphic effects on cellular immunoreactivity (natural killer and lymphokine-activated killer cell cytotoxicity and interleukin-2-induced T-cell proliferation), with females presenting a relatively immunosuppressed phenotype compared to males. Moreover, following chronic antidepressant treatment, thymic monoamines presented sex-related alterations, as well as intriguing associations with peripheral T-cell responses. This study highlights the sex-related effects of chronic clomipramine treatment and CMS application on the cellular arm of immunity, and represents a preliminary exposé of a thymus-dependent route pertaining to the interactions between antidepressants and the immune system.

Opposite roles of metastasin (S100A4) in two potentially tumoricidal mechanisms involving human lymphocyte protein Tag7 and Hsp70

We compare the physical and functional interactions between three widespread multifunctional proteins [metastasin (Mts1/S100A4), innate immunity-related Tag7/PGRP-S, and Hsp70] in two experimental models relevant to host-tumor relationships on humoral and cellular levels. (i) Tag7 and Hsp70 in solution or in a lymphocyte make a stable binary complex that is highly cytotoxic for some tumor cells. Here, we show that Mts1 prevents Tag7.Hsp70 assembly in solution, and an excess of Mts1 disrupts the existing Tag7.Hsp70 complex; accordingly, Tag7.Hsp70 cytotoxicity (exemplified with L929 cells) is diminished in the presence of excess Mts1. (ii) Tag7 exposed on a specialized subset of lymphokine-activated killer cells makes specific contact with Hsp70 exposed on some HLA-negative tumor cells, thus enabling FasL/Fas-mediated induction of apoptosis. Here, we show that some CD4(+)CD25(+) cells coexpose Mts1 with Tag7 and FasL, that Mts1 and Tag7 closely contact the same Hsp70 molecule on the target K562 cell (as evidenced by cross-linking), and that killing of such targets is abolished by Mts1-specific antibodies (or selective removal of Mts1-exposing lymphocytes). Thus, this phenotype active against immunoevasive cancerous cells is defined as CD4(+)CD25(+), FasL(+), Tag7(+)Mts1(+) (approximately 0.5% of total lymphocytes in culture). Remarkably, similar effectors with at least the same activity are often found in fresh donor blood samples (approximately 10(4) effectors/mL). Thus, our models suggest that interactions between the three proteins in different situations may have opposite functional outcomes as regards antitumor defense, immune escape, and metastasis.

Granzyme F induces a novel death pathway characterized by Bid-independent cytochrome c release without caspase activation

Granzyme F (GzmF) belongs to a unique group of granzymes in mice. Murine GzmF is highly expressed in NK3.1 cells and in lymphokine-activated killer (LAK) cells. However, the manner in which GzmF works in granule-mediated cytolysis is unknown. In this study, we first demonstrated that GzmF causes a novel cell death pathway. The death is characterized by an externalization of phosphatidylserine, by nuclear condensation, mitochondrial damage, cytochrome c (cyt c) release, caspase inactivation and single-stranded DNA nicking. GzmF-induced chromatin was incompletely condensed and segmented at the nuclear periphery. Cellular organelles were damaged and the cytoplasm showed an extensive vacuolization that is reminiscent of necroptosis. GzmF can cause rapid mitochondrial swelling, depolarization and reactive oxygen species accumulation. GzmF-induced death does not involve caspase activation, Bid cleavage or activation of DNA nickase NM23H1. GzmF-silenced LAK cells showed reduced cytotoxicity against caspase-inhibited target tumor cells. Moreover, cyt c release is independent of Bid or Bax/Bak. We further showed that GzmF impairs mitochondrial electron transport to abolish ATP generation. ATP decline may contribute to a failure of apoptosome formation, leading to caspase inactivation.

The CD8+ population of LAK cells can lyse both HLA-positive and HLA-negative cancer cell lines

The CD8+ population of LAK cells can lyse both HLA-positive and HLA-negative cancer cell lines

Impaired differentiation and cytotoxicity of natural killer cells in systemic lupus erythematosus

To determine the cytotoxicity of natural killer (NK) cells and the level of differentiation of hematopoietic stem cells (HSCs) into NK cells in systemic lupus erythematosus (SLE). Patients with SLE (n=108), rheumatoid arthritis (RA; n=90), Behçet's disease (n=39), or ankylosing spondylitis (n=41) and healthy control subjects (n=173) were enrolled in the study. NK cell levels, NK cell cytotoxicities, and lymphokine-activated killer (LAK) activities against K562 cells were measured by flow cytometry. Gene expression was assessed by reverse transcription-polymerase chain reaction. NK cells were differentiated from peripheral blood and bone marrow HSCs in vitro. Percentages and absolute numbers of NK cells, cytotoxicities, and LAK activities were significantly lower in the peripheral blood of SLE and RA patients than in that of healthy controls. In particular, this NK cell deficiency was more prominent in patients with lupus nephritis and those with thrombocytopenia. Notably, purified NK cells derived from SLE patients, but not RA patients, were found to have lower cytotoxicities and LAK activities than those from healthy controls. This defect of NK cells in SLE patients was found to be related to lower numbers of NK precursors and to the down-regulation of perforin and granzyme in NK cells. The proliferative capacity of HSCs, the percentages of NK cells differentiated from HSCs, and NK cell cytotoxicities were significantly lower in SLE patients. In SLE patients, circulating levels of NK cells were diminished and their cytotoxicities were impaired. Furthermore, the differentiation of HSCs into NK cells was found to be defective. These abnormalities possibly contribute to immune system dysregulation in SLE.

Impact of surgery and chemotherapy on cellular immunity in pancreatic carcinoma patients in view of an integration of standard cancer treatment with immunotherapy

As surgery and chemotherapy may act as adjuvants providing antitumor immunity benefits, we ran phenotypical and functional immunomonitoring in patients with resectable pancreatic adenocarcinoma and advanced metastatic disease receiving combined treatment (cisplatin, gemcitabine, 5-FU). Blood was taken before/one month after resection; before/during chemotherapy. Controls were age- and gender-matched. Circulating lymphocyte, myeloid and plasmacytoid dendritic cell (MDC and PDC) subsets were examined by flow cytometry; functional activity by mixed lymphocyte reaction (MLR) for DC allostimulation, through 4-h 51Cr-release assay for Natural Killer (NK) and lymphokine-activated-killer (LAK) cell cytotoxicity; ELISA for spontaneous/activated cytokine release by PBMC and T cells. Significant differences occurred in several parameters between pretreatment patient and control values: fewer CD8+ cells and increased apoptosis-prone CD3+/CD95+ lymphocytes, higher frequency of MDC, reduced allostimulatory activity by ex vivo-generated DC, depressed LAK activity, elevated IL-10 and IL-12p40 production; impaired IL-12p70 and IFN-gamma production by stimulated PBMC and T cells. Only IL-12p70 level was correlated with survival. One month after radical, but not palliative surgery, the percentage of T-lymphocytes coexpressing CD3/CD95 decreased significantly, the stimulatory capacity of DC increased, and LPS-induced IL-12p70 release by PBMC rose concomitantly with the anti-CD3 stimulated-IFN-gamma production by T cells. In patients with locally advanced or metastatic disease, one and/or two combined drug cycles increased percentage of CD4+ cells and LAK cell cytotoxicity and decreased PDC frequency and spontaneous/LPS-stimulated IL-10 by PBMC. Results suggest immunological changes induced by surgical resection/combined chemotherapy indicate specific precisely-timed windows of opportunity for introducing immunotherapy in pancreatic cancer, possibly improving survival in this highly lethal disease.

High-Dose Intensity Pulse Interleukin-2 with Famotidine in Metastatic Kidney Cancer

Lymphokine-activated killer cell (LAK) activity against tumor cell lines may be induced by intravenous (i.v.) interleukin-2 (IL-2). Daily short infusions (pulses) have been developed to decrease toxicity while maintaining the anticancer activity of this agent against kidney cancer. The anthihistamine, famotidine, may increase IL-2 uptake by the IL-2 receptor on lymphocytes. We have treated 12 patients with metastatic kidney cancer, using pulse IL-2 (18 million IU/M(2) i.v.) over 15-30 minutes, preceded by famotidine (20 mg I.V. daily for 5 days) on an oncology inpatient unit. Cycles were repeated every 3 weeks until disease progression. Patient characteristics were as follows: 9 males with a median age of 66 years (range, 48-74), and median Eastern Cooperative Oncology Group performance status of 1; common metastatic sites included in the lungs 9 and lymph nodes 3. Median number of cycles received was 2 (range, 1-5). The most common toxicities were fever, rigors, and hypomagnesemia. Two (2) patients had partial responses (17% response rate). Responses occurred in the liver (11.5 months) and lung, pleura, and lymph nodes (3 months). Pulse IL-2 with famotidine shows activity in kidney cancer.

A Combination Therapy of Gemcitabine With Immunotherapy for Patients With Inoperable Locally Advanced Pancreatic Cancer

Dendritic cell (DC) therapy frequently induces a measurable immune response. However clinical responses are seen in a minority of patients, presumably due to insufficient expansion of antigen-specific cytotoxic T lymphocytes (CTLs) capable of eradicating tumor cells. To increase therapeutic efficacy of DC-based vaccination, we have undertaken the first clinical trial involving a combination therapy of gemcitabine (GEM) with immunotherapy for patients with inoperable locally advanced pancreatic cancer. Patients (n = 5) received the treatment course, which consisted of intravenous GEM administration at 1000 mg/m (day 1) and the endoscopic ultrasound-guided fine-needle injection of OK432-pulsed DCs into a tumor, followed by intravenous infusion of lymphokine-activated killer cells stimulated with anti-CD3 monoclonal antibody (CD3-LAKs) (day 4), at 2-week intervals. No serious treatment-related adverse events were observed during the study period. Three of the 5 patients demonstrated effective responses to this clinical trial; 1 had partial remission and 2 had long stable disease more than 6 months. In the patient with partial remission, it has been shown that DC-based vaccination combined with GEM administration induces tumor antigen-specific CTLs. This combined therapy was considered to be synergistically effective and may have a role in the therapy of pancreatic cancer for inducing tumor antigen-specific CTLs.

Enhancement of Natural Killer Cell Activity and Phagocytosis in Healthy Subjects by Immulina, a Spirulina Extract Enriched for Braun Type Lipoproteins

Immulina is a commercial extract of Spirulina (Arthrospira) platensis that is standardized by biological activity. We previously reported that this extract is a potent activator of THP-1 monocytes in vitro and that oral consumption enhanced several immunological functions in mice [1]. In this study we further characterized Immulina by determining that Braun type lipoproteins are responsible for a major portion of the in vitro monocyte activation exhibited by this material. In order to understand the effect of Immulina on the human immune system, a pilot study was conducted on ten healthy individuals who supplemented their diet with Immulina (400 mg/day) for seven days. Blood was drawn from the participating individuals at two time points: before and after seven days of Immulina supplementation. Changes in mononuclear and polymorphonuclear phagocytosis were determined in heparinized whole blood as well as the cytotoxicity exhibited by natural killer (NK) and lymphokine activated killer cells. We observed statistically significant increases both in tumor cell killing by NK cells (p = 0.0019) and in phagocytosis by blood mononuclear cells (p = 0.0124) after Immulina supplementation. Acknowledgements: This research was partly funded by a USDA, Agricultural Research Service Specific Cooperative Agreement No. 58-6408-012. Immulina capsules were supplied by Scandinavian Clinical Nutrition Denmark A/S, Greve, Denmark.

Significant Impairment in Immune Recovery After Cancer Treatment

Although immunosuppression from cancer adjuvant therapy has been documented, how these suppressed immune responses recover to baseline values after completion of cancer adjuvant therapy has not been studied systematically. The objective of this study was to examine the probability of immune recovery after cancer adjuvant therapy and the potential impact of cancer adjuvant therapy type and cancer stage on immune recovery in patients with newly diagnosed breast cancer. In a repeated-measures design, immune responses were measured four times in 80 patients with early-stage breast cancer: before and at 2, 6, and 12 months from the beginning of cancer adjuvant therapy. Natural killer cell activity, lymphokine-activated killer cell activity, lymphocyte proliferation, CD subsets (CD4, CD8, and CD56), and cytokines (interferon-gamma, interleukin [IL]-2, IL-4, IL-6, and IL-1alpha) were selected for their relevance to breast cancer. Immune recovery was defined by the level of immune response reaching to and above baseline levels. Data were analyzed using a multivariate generalized linear mixed-model approach. Delayed immune recovery to pretreatment baseline levels continued to the 12-month time point in all parameters. The percentages of immune recovery ranged from 6% to 76% of the patients, varying among immune parameters. Overall, immune recovery was poorer for interferon-gamma, IL-2, IL-4, lymphocyte proliferation, and natural killer cell activity than was for CD subsets and IL-6. The type of cancer adjuvant therapy, not cancer stage, showed selective influence on immune recovery. Chemotherapy or chemotherapy and radiotherapy combination significantly delayed IL-2 recovery, whereas radiotherapy significantly delayed IL-4 recovery. Immune recovery after breast cancer adjuvant therapy is delayed significantly for an extended time period in numerous immune parameters. The type of cancer adjuvant therapy has selective influence on immune recovery. Future investigations are warranted to elucidate the time course of immune recovery, clinical significance of poor immune recovery, and factors influencing immune recovery to develop potential interventions.