First phase implementation of cardio-oncology program in the middle-income country of Costa Rica at Hospital Metropolitano healthcare system

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Background: Developing a cardio-oncology program in a middle-income country like Costa Rica can present unique opportunities and challenges. Hospital Metropolitano is a health care system in Costa Rica with a network of two hospitals, 36 clinics, and over 150,000 patients enrolled in its health plan, Medismart. Here we summarize our program, and the initial results of the implementation phase, hoping that institutions with similar resources in low-and-middle-income countries will use this as guidance to develop their own cardio-oncology program. Methods: A cardio-oncology committee was established in May 2019 and includes medical providers, clinical coordinators, administrative workers, and nursing and laboratory staff. A 4-month pre-launch period was established to create an institutional protocol after we reviewed guidelines and literature from similar programs in the United States and Europe. The protocol targets both active cancer patients undergoing treatment and cancer survivors. The program was launched in September 2019 and is currently in the first phase of implementation. Results: During the first phase of implementation, the program was limited to the outpatient setting and patients were referred exclusively by the medical oncology providers from our health care system. In this period, 28 patients met criteria for referral and all enrolled according to our protocol. The median age of our patients was 49 (range 16-77). 25 patients (89%) were female and 20 (71%) had a diagnosis of breast cancer. At the time of enrollment, 21 (75%) were receiving active cancer treatment and 7 (25%) were identified as cancer survivors. All patients are being followed prospectively. A committee review at the end of the first phase of implementation revealed that the most important challenges that the program needs to address for the second phase of implementation include the following: 1) patient education and outreach, 2) cost of care associated with the interventions recommended by the protocol, and 3) data tracking/registry given the lack of an electronic medical record. Conclusions: Our program represents a real-life experience of the challenges and opportunities that institutions in middle-income countries need to consider when launching such initiatives. To our knowledge, this is the first cardio-oncology program formally established in Central America and we are committed to continue to measure our outcomes prospectively and share these with the global oncology community.

Oncosmart: A Private Initiative to Improve Breast Cancer Care in Costa Rica

Purpose

Founded in 2010, Hospital Metropolitano is the fastest growing health care system in Costa Rica with a network of two hospitals, 27 clinics, and more than 90,000 patients enrolled in its health plan, Medismart. Given the challenges faced by the national public health care system in providing cancer care, the Oncosmart program was launched in November 2016 with the goal of providing population-based cancer screening, diagnostics, cancer treatment, and survivorship care. The program has no restrictions on preexisting conditions and has a monthly membership cost of $14 USD per patient. Here, we summarize our breast cancer program results during the first 16 months of implementation.

Methods

We performed a retrospective analysis that evaluated data from our radiology department, cancer center, and survivorship program. We determined the number of patients with breast cancer who were diagnosed and/or received care in our health care system from November 2016 to March 2018.

Results

During this period analyzed, 5,687 mammograms were performed at our health care system and 215 patients were reported to have a Breast Imaging Reporting and Data System 4 to 5 requiring a breast biopsy. Of these, 24% were diagnosed with breast cancer, 36% had a nonmalignant breast condition, and 41% were false positives. Among patients with newly diagnosed breast cancer, 11% had noninvasive breast cancer and 89% had invasive disease. Twenty-seven percent of all breast cancer diagnosis occurred in women younger than age 50 years and two patients were diagnosed with a BRCA1/2 mutation. All biopsies performed at our program were reported within 30 days from abnormal imaging. During this period, we performed 53 breast cancer surgeries and provided chemotherapy and/or endocrine therapy to 32 patients, and among all patients who followed-up in the survivorship clinic, 22 followed-up for breast cancer survivorship.

Conclusion

Oncosmart is a low-cost and effective private initiative that improves access to breast cancer screening and breast cancer care in the middle-income country of Costa Rica. On the basis of national statistics, after 16 months of implementation, approximately 4% to 5% of all patients with breast cancer in the country are diagnosed within our program.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/jco/site/ifc . Andres Wiernik Consulting or Advisory Role: Grupo Montecristo Leonardo Lami Employment: Roche, Genetech (I) Travel, Accommodations, Expenses: Roche/Genetech (I) Marissa Durman Consulting or Advisory Role: Grupo Montecristo

Clinical implications of the 2012 US Preventive Services Task Force (USPSTF) PSA screening recommendation in prostate cancer diagnoses and 5-year survival at a Minnesota safety net health care system

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Background: Prostate specific antigen (PSA) screening for prostate cancer has declined following the USPSTF 2012 recommendation. How screening rates and prostate cancer diagnoses have subsequently changed in a racially diverse patient population is not well defined. In this study, we aim to determine the impact of the USPSTF screening recommendation in the Hennepin Healthcare System (HHS) in the state of Minnesota. Methods: A single-institution retrospective analysis of data from our electronic health record, to identify the characteristics of PSA screening and new prostate cancer diagnoses for men ≥50 years between 2008 and 2015. Data before and after May 2012 were compared. P-values were calculated using binominal and generalized linear models. Results: Nearly 22,000 patients underwent PSA screening from 2008 to 2015. PSA screening rates decreased after May 2012 for the four largest demographics represented (p < 0.001). Hispanics and Blacks were more likely to be screened when compared to Whites and Asians (p < 0.05). 319 cases of prostate cancer were diagnosed from 2008 to 2015 with 87 cases (27.3%) diagnosed by PSA-screening. The number needed to screen to diagnose one patient with prostate cancer at HHS was 137.5, and 9.5% of patients (1146 patients) had a false positive PSA that led to further testing or a biopsy. $56,090 was spent in screening costs per diagnosis of early stage prostate cancer via screening. Patients diagnosed from screening were less likely to present with high Gleason scores (8-10) compared to non-screening diagnosis (8% vs 23.3%, p < 0.01). The 5-year survival percentage (prostate cancer mortality) was improved for those patients diagnosed by PSA screening vs the non-screened group (100% vs 89.3%, p < 0.05). Conclusions: PSA screening has declined at HHS since the USPSTF recommendation against prostate cancer screening. Implementation of PSA screening in our healthcare system is expensive and leads to a high number of false positives. Despite this, the 5-year survival from prostate cancer is significantly higher when patients are diagnosed by PSA screening.

Mammography screening and detection of early stage breast cancer in Hispanic and African American women at a Minnesota safety net healthcare system

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Background: Approximately 12% of breast cancer cases occur in women younger than 50 years, per SEER data from 2012. Hispanic women are known to present at a younger age and African American women with more advanced stage disease. In this study, we describe the impact of age and race on the initial presentation of breast cancer among minority women treated at the Hennepin Healthcare System (HHS) in the state of Minnesota. Methods: A single-institution retrospective analysis of data from our electronic health record of all breast cancer diagnoses from 2010-2015. Cases were compared by age ( < 50 or > 50 years), race (Caucasian, African American, Hispanic, other), stage (AJCC 7th edition), and method of diagnosis (self-reported mass or screening mammography). Results: A total of 315 breast cancer diagnoses occurred at HHS from 2010-2015. In our cohort, 29% of all breast cancer cases were diagnosed in women < 50yrs. Hispanic and African American women had higher rates of diagnosis at < 50yrs compared to Caucasian women (38.9% vs 37.1% vs 18.1 respectively, p < 0.05). Early stage cancer (stage 0 or I) accounted for most diagnoses in those > 50yrs (54.8%), while advanced stage (stage II-IV) was more prevalent in the < 50yrs age group (59.5%) (p < 0.05). Of all women diagnosed with breast cancer, 63% presented with a self-reported mass and 37% were diagnosed by screening mammography. Hispanics and African American women had a higher rate of presentation with a self-reported mass (74% and 66% respectively) compared to Caucasian women (55%). Women with breast cancer < 50yrs were more likely to present with a self-reported mass than women > 50yrs (80% vs 55%, p < 0.05). 92% of Hispanic and 80% of African American women < 50yrs presented with a self-reported mass, compared to 62% of Caucasian women (p = 0.095). Conclusions: At our institution, Hispanic and African American women are diagnosed at a significantly younger age than Caucasian women, and those diagnosed at a younger age have more advanced disease. Presenting with a self-reported mass is very common for young non-Caucasian women. Whether screening mammography can be better utilized to change these trends requires further study.

Health disparities in advance care planning at a safety-net hospital

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Background: Advance health care directives (AHCDs) are recommended by ASCO as a strategy to improve compliance with patient wishes at the end-of-life, thereby facilitating appropriate use of health care resources. We already know too few cancer patients complete AHCDs, but we know less about barriers to their completion. This study assessed the frequency with which AHCDs were completed in different ethnic groups and whether hospice enrollment varied by ethnicity. Methods: Retrospective analysis conducted at Hennepin County Medical Center in Minneapolis, MN with review of the cancer registry data from 2008 to 2013. Data were collected for deceased patients with stage III-IV cancer from the time of diagnosis through death. Demographics, AHCD, hospital deaths, enrollment in hospice, and individual patient data were analyzed using logistic regression, adjusting for both race and language as covariates. Results: From 2008 to 2013, there were 273 patients diagnosed with stage III-IV cancer and followed through death. Fourteen percent of patients were non-English speaking. Thirty-one percent were African American (AA), 4% were Hispanic, and 4% were Asian. Only 21% of patients completed an AHCD during their care, and none were Asian or Hispanic. English speakers were almost five times more likely than non-English speakers to have an AHCD (OR = 4.66, 95% CI = (1.06, 20.46), p = 0.04). Fifty-one percent of English-speaking patients enrolled in hospice compared to 39% of non-English-speaking patients (p = 0.08). Sixty percent of patients with an AHCD enrolled in hospice compared to 46% of those patients without an AHCD (p = 0.10). Forty-three percent of patients with an AHCD died in the hospital, 33% of whom died in an intensive care unit (ICU), versus 46% without an AHCD, 49% of whom died in an ICU. Of patients with advanced cancer, 46% died in the hospital and 21% died in the intensive care unit (ICU). Conclusions: Non-English-speaking patients are far less likely to have an AHCD than English speakers. Some ethnicities in our study had no patients with an AHCD. Since completing an AHCD may increase hospice enrollment and decrease ICU deaths, strategies to promote advance care planning are urgently needed, particularly with non-English speaking patients.

Targeting natural killer cells to acute myeloid leukemia in vitro with a CD16 x 33 bispecific killer cell engager and ADAM17 inhibition

PURPOSE

The graft versus leukemia effect by natural killer (NK) cells prevents relapse following hematopoietic stem cell transplantation. We determined whether a novel bispecific killer cell engager (BiKE) signaling through CD16 and targeting CD33 could activate NK cells at high potency against acute myelogenous leukemia (AML) targets.

EXPERIMENTAL DESIGN

We investigated the ability of our fully humanized CD16 × CD33 (CD16 × 33) BiKE to trigger in vitro NK cell activation against HL60 (CD33(+)), RAJI (CD33(-)), and primary AML targets (de novo and refractory) to determine whether treatment with CD16 × 33 BiKE in combination with an ADAM17 inhibitor could prevent CD16 shedding (a novel inhibitory mechanism induced by NK cell activation) and overcome inhibition of class I MHC recognizing inhibitory receptors.

RESULTS

NK cell cytotoxicity and cytokine release were specifically triggered by the CD16 × 33 BiKE when cells were cultured with HL60 targets, CD33(+) de novo and refractory AML targets. Combination treatment with CD16 × 33 BiKE and ADAM17 inhibitor resulted in inhibition of CD16 shedding in NK cells, and enhanced NK cell activation. Treatment of NK cells from double umbilical cord blood transplant (UCBT) recipients with the CD16 × 33 BiKE resulted in activation, especially in those recipients with cytomegalovirus reactivation.

CONCLUSION

CD16 × 33 BiKE can overcome self-inhibitory signals and effectively elicit NK cell effector activity against AML. These in vitro studies highlight the potential of CD16 × 33 BiKE ± ADAM17 inhibition to enhance NK cell activation and specificity against CD33(+) AML, which optimally could be applied in patients with relapsed AML or for adjuvant antileukemic therapy posttransplantation.

Abstract 533: Dendritic cells are professional educators of Natural Killer cells

Dendritic cells (DCs) and Natural Killer (NK) cells are important components of innate immunity. NK cells are the principal effectors of the innate immune system and play an important role in tumor surveillance and anti-viral immunity. It has been commonly accepted that CD56bright NK cells are the main source of cytokine production while CD56dim are mostly responsible for cytolytic activity and target cell killing. CD56dim NK cells acquire KIR (Killer cell Immunoglobulin-like Receptors or KIR) receptors by a process called NK cell education or licensing. NK cell education has been defined as the mechanism by which NK cell acquire inhibitory KIR and how signaling by specific cognate ligands leads to gain of NK cell function. DCs are antigen presenting cells which act as sentinels for the immune system by engulfing pathogens, processing and presenting them to CD4 and CD8 T cells. Interactions between dendritic cells and natural killer cells have been extensively studied but the role that DCs might play in NK cell education remains elusive and poorly understood. We evaluated the in-vitro interaction between adult monocyte-derived dendritic cells and natural killers cells from healthy donors. Mature monocyte-derived dendritic cells (mdDCs) were co-cultured with KIR negative and KIR positive NK cells in addition to different concentrations of IL-15. After 5 days of co-culture; the KIR negative population (0.8% KIR positive after 5 days of co-cultured) acquired up to 3.8% KIR expression when co-cultured with mdDCs (1:1 ratio) and 0.5 ng/mL of IL-15. In addition, a population of NK cells which expressed 28% KIR after 5 days of culture expressed up to 38% KIR when mdDCs and 0.5 ng/mL of IL-15 were added to the culture. Of note, enhanced KIR expression (as a marker of maturation) required both IL-15 and mdDcs as no effect was seen when mdDcs or IL-15 were added alone. Aside from the differences noted in KIR expression, a population of CD56dim NK cells became CD56bright when both KIR negative (8.44% to 23.6%) and KIR positive (0.8% to 24.9%) NK cells were co-cultured with mdDCs and IL-15. In conclusion, our studies suggest that dendritic cells have the ability to educate NK cells and that this process is dependent on IL-15, which can be trans-presented through IL-15Rα on DCs. Dendritic cells in addition to IL-15 may also revert a population of mature CD56dim NK cells to a CD56bright NK cells, which are considered less differentiated, suggesting that NK maturation can be bidirectional and may exhibit more plasticity than previously recognized.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 533. doi:1538-7445.AM2012-533

Alloreactive natural killer cells in hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) for leukemia can play a major role in reducing the risk of relapse by inducing a graft versus leukemia (GVL) effect. Here, we review the effectiveness of mismatching inhibitory killer-cell-immunoglobulin-like receptors (KIR) on donor natural killer (NK) cells as a mechanism for GVL. We review the range of KIR and the importance of T cell and NK cell content of the graft, together with considerations of the graft source. Further understanding of conditioning and mechanisms to reduce graft versus host disease (GVHD) will improve our ability to manipulate NK cells in HSCT.

Potential nitrite scavengers as inhibitors of the formation of N-nitrosamines in solution and tobacco matrix systems

The ability of 20 compounds, all but one tobacco constituents, to inhibit the formation of tobacco-specific N-nitrosamines (TSNA) was investigated in buffer and detergent solution and in tobacco midrib and lamina systems. In solution at pH 5.5, ascorbic acid and the phenolic acids caffeic and ferulic acid were the most potent inhibitors of the reaction between nornicotine and nitrite, with nearly complete inhibition at molar ratios test compound/nitrite > 1:1. Also, cysteine > dihydrocaffeic acid > protocatechuic acid approximately catechin acted as strong inhibitors with >90% inhibition at a ratio of 3:1. Lower inhibitions were observed with chlorogenic acid > p-coumaric acid > sclareol > serine. Rutin showed an inhibition of 34% at a ratio of 0.1:1. Sclareol, alanine, proline, and serine did not significantly affect the N-nitrosonornicotine (NNN) formation. alpha-Tocopherol and glutathione enhanced NNN formation at pH 5.5 but were inhibitors at pH 3. Cinnamic acid, vanillic acid, eugenol, and esculin enhanced NNN formation. Increased NNN formation was also observed for dihydrocaffeic acid, chlorogenic acid, protocatechuic acid, and catechin at a less-than-equimolar ratio of test compound to nitrite. The tobacco matrix experiments were performed with air-cured, ground tobacco midrib and lamina. Caffeic acid, ferulic acid, dihydrocaffeic acid and catechin were potent inhibitors of the formation of TSNA in the midrib as well as in the lamina. Also protocatechuic acid, glutathione, ascorbic acid, p-coumaric acid, chlorogenic acid and cysteine were inhibitors, while alpha-tocopherol and rutin inhibited the reaction in the midrib but not in the lamina. Cinnamic acid, vanillic acid, eugenol, alanine, proline and serine showed small effects only. The molar ratio of secondary alkaloid(s)/nitrite in the test systems were 0.1:1 (solution), approximately 0.25:1 (midrib), and approximately 1:1 (lamina) and is most likely the major contributor to the observed order of inhibition potency (solution > midrib > lamina) of the test compounds. The vicinal phenolic hydroxyl groups of polyphenols and the simultaneous presence of a phenol group and an olefinic bond in hydroxycinnamic acids were the most characteristic structural elements of the potent inhibitors.

Influence of human plasma high density lipoproteins from septic patients on different functions of normal human neutrophils

High Density Lipoproteins (HDL) from three patients with E. coli sepsis contained high, low and no Serum Amyloid Protein (Apo SAA), respectively. Preincubation of neutrophils from healthy persons for half an hour with sepsis HDL as well as normal HDL increased the phagocytosis, the stimulated nitroblue tetrazolium reduction, the chemotaxis and the random migrations of these cells. However, for all these functions, lower values were obtained after incubation with sepsis HDL containing high amounts of apo SAA than with normal HDL. A qualitative change of HDL might thus in part be responsible for the decreased function of neutrophils noted during the acute phase of bacterial infections.

Significance of oxygen availability for release of oxygen free radicals and lysozyme by neutrophils

Neutrophilic granulocytes were exposed to an atmosphere of nearly 100% oxygen (hyperoxia) for one hour. The nitroblue tetrazolium (NBT) reduction, reflecting oxygen radical release, was decreased both in resting and stimulated cells, but lysozyme release was unchanged. Short time exposure of patients to oxygen hypertension might therefore be beneficial as therapy, in conditions where reduced production of oxygen radicals is required. The NBT reduction of resting and stimulated neutrophils in an atmosphere of purified argon (hypoxia) was also considerably decreased, and the lysozyme release unchanged. This reflects the anaerobic conditions in abscesses, where the contribution of neutrophil oxygen metabolites to the killing of microorganism might be reduced.

Morphology and function of blood monocytes after incubation with lung surfactant

Human blood monocytes were incubated for different periods of time with lung surfactant (phospholipid concentration 1-2.5 mg/ml). After short-term (30 min) incubation, there was an increase in the nitroblue tetrazolium (NBT) reduction of the monocytes both at rest and during stimulation with E. coli bacteria, and enhanced ingestion of fluorescein-labelled yeast particles. Electron microscopic examination of the same monocytes showed an active cell surface with numerous protrusions. Long-term (24 h) incubation with surfactant resulted in a reduced ability of the cells to adhere to plastic dishes. Although the NBT-reduction of resting monocytes was increased after long-term incubation with surfactant, the additional enhancement of NBT-reduction after stimulation with bacteria was decreased. These cells were rounded, usually devoid of surface structures, their nuclei were condensed, and their cytoplasm filled with surfactant material. Thus, monocytes are initially activated in the presence of surfactant, but if the cells become overfed with surfactant lipids their functional capacity decreases.

High-density lipoproteins inhibit the bacterial lipopolysaccharide mediated increase in oxidative metabolism and lysozyme release by neutrophilic granulocytes in vitro

The effects of purified Salmonella endotoxin (LPS) and of LPS combined with isolated human plasma high density lipoproteins (HDL) on oxidative metabolism, measured by nitroblue tetrazolium (NBT)-test, and on lysozyme release of human granulocytes have been studied in vitro. A considerable increase in the NBT-reduction and in lysozyme release was noted in granulocytes exposed to LPS. The stimulating effect of LPS on NBT-reduction and lysozyme release was significantly diminished when the cells were incubated with LPS together with HDL. These observations suggest that HDL in vivo may play an important part in inhibition of metabolic changes induced in granulocytes by LPS which leads to the production and secretion of tissue damaging mediators.

Toxicology of nickel

Rabbits were exposed to low levels of airborne metals for 1-8 months, 5 days/week, 6 hours/day. After exposure, lung tissue was examined by light and electron microscopy. Macrophages lavaged from the left lung were examined morphologically and functionally. Phospholipids were analysed in lung tissue or lavage fluid. Metallic nickel dust, 0.1-1 mg/m3, affected alveolar macrophages, alveolar epithelial type II cells and phospholipids. In the lung tissue, nodular accumulation of macrophages was seen, and the volume density of alveolar type II cells was elevated. The amount of phospholipids was markedly increased, mainly due to an increase in disaturated phosphatidylcholines. After 1 month of exposure the macrophages appeared active. After 3 months they appeared 'overfed' and inactive. Metallic iron, chromium and cobalt did not produce the same effects as nickel. Exposure to 0.2 mg/m3 soluble nickel as nickel chloride produced almost identical effects to those of metallic nickel, indicating that the effect of the metallic nickel particles was caused by nickel ions. Exposure to cadmium chloride produced nearly all the effects produced by nickel chloride. However, cadmium chloride increased the level of lysozyme in the macrophages whereas nickel chloride decreased it. Cadmium chloride also produced interstitial alveolitis and cytoplasmic blebs on the surface of the macrophages. Cobalt chloride affected the growth of the type II cells, which formed nodules, but did not seem to affect the production of surfactant material by those cells. Copper chloride produced no effect apart from a slight increase in volume density of the type II cells. Thus, of four divalent metal ions, three (Ni2+, Cd2+ and Co2+) in similar concentrations in the inhaled air produced clear but different pathological effects in the lungs.

Opposite effects of different plasma lipoprotein fractions on granulocyte function

Different plasma lipoprotein fractions in physiological concentrations have opposite effects on the phagocytosis and migration of human neutrophilic granulocytes. Preincubation for half an hour with very low density lipoproteins decreased the phagocytosis as well as the chemotactic and random migrations of the cells, while preincubation with high density lipoproteins increased the same functions. No effects were seen with low density lipoproteins. It is suggested that disturbances in plasma lipoprotein pattern may affect the function of phagocytes.

Rabbit alveolar macrophages after inhalation of soluble cadmium, cobalt, and copper: a comparison with the effects of soluble nickel

Rabbits were exposed to aerosols of chlorides of cadmium, copper, and cobalt (0.4-0.6 mg/m3 as metal) for 1 month (5 days/weeks and 6 hr/day). The effects of alveolar macrophages were compared with earlier reported effects of nickel chloride (0.3 mg/m3 as Ni). Effects of Cd2+ exposure resembled those of Ni2+ exposure. The number of macrophages in lavage fluid and the variance of cell diameters were thus increased and many cells contained lamellated inclusions. Contrary to macrophages from Ni2+-exposed rabbits, the surface of about 50% of the cells had cytoplasmic blebs. However, such cells were rarely seen by scanning electron microscopy. There were significantly more polymorphonucleated neutrophils and small lymphocytes, suggesting lung parenchymal damage. Cells from Cd2+-exposed animals, like cells from Ni2+-exposed ones, showed an increased oxidative metabolic activity after stimulation with Escherichia coli bacteria. Bactericidal capacity, on the other hand, tended to be enhanced rather than decreased, as in the nickel experiment. After CO2+ exposure, the number of macrophages was slightly increased in the lavage fluid and the cells showed an increased metabolic activity both at rest and upon stimulation with bacteria. Cu2+ exposure gave a slight increase in lamellated inclusions in the macrophages.

Rabbit lung after inhalation of soluble nickel. I. Effects on alveolar macrophages

Alveolar macrophages from eight rabbits, exposed for about 1 month (5 days/week, 6 hr/day) to an aerosol of nickel chloride, 0.3 mg/m3 (as Ni), were studied. The number of macrophages in the lavage fluid and the variance of the cell diameter increased. The macrophages contained laminated structures and most cells had an active cell surface. A few macrophages had a large number of laminated structures and a smooth cell surface. The capacity of the macrophages to reduce nitroblue tetrazolium (NBT) tended to be increased at rest and was significantly increased after stimulation with Escherichia coli. The bactericidal capacity of the macrophages was decreased. The effects were similar to those earlier described after exposure of rabbits for 1 month to about 1 mg/m3 of metallic nickel dust. After exposure both to metallic and soluble nickel the effects are probably caused by an increased amount of surfactant produced by the type II cells in response to nickel ions.

Rabbit lungs after long-term exposure to low nickel dust concentration. II. Effects on morphology and function

For 4 and 8 months (5 days/week, 6 hr/day) rabbits were exposed to 0.13 +/- 0.05 (mean +/- SD) mg/m3 of metallic nickel dust. Volume density of alveolar type II cells was estimated with electron microscopy. Lavaged alveolar macrophages were studied with light and electron microscopy and their abilities to reduce nitroblue tetrazolium (NBT) and to phagocytize particles were tested. The effects seemed to be similar after 4 and 8 months of exposure and when the exposed animals were combined, volume density of type II cells was increased and also significantly correlated with concentration of disaturated phosphatidylcholines in the lung. The macrophages had an active surface. Their NBT activity at rest was increased but a further increase during stimulation with E. coli was low, suggesting an impaired function. Phagocytic activity, however, was not significantly changed.

The effect of intralipid on mononuclear and polymorphonuclear phagocytes

Eight healthy subjects were given Intralipid, a soybean oil emulsion, 20% intravenously for 2 h. During the infusion a significant increase in the nitroblue tetrazolium-reduction of blood monocytes was noted. Preincubation of monocytes in vitro with Intralipid (20 to 100 mg/ml) for 30 min was found to increase the ability of the cells to migrate chemotactically and to phagocytize yeast particles. On the contrary, when neutrophilic granulocytes were preincubated with Intralipid in the same concentrations for 30 min. their nitroblue-tetrazolium-reduction, chemotactic and spontaneous locomotion, as well as their ingestion of yeast particles was depressed.

The effect of phospholipid-containing surfactant from nickel exposed rabbits on pulmonary macrophages in vitro

Alveolar macrophages from 9 normal rabbits were incubated in vitro for 3 h with and without phospholipid-containing surfactant from nickel-treated ones. The macrophages treated with surfactant showed morphological and functional criteria of increased activity. The cell surface had many protrusions and the cytoplasma contained several lamellated structures. The oxidative metabolism, measured by the nitroblue tetrazolium (NBT)-test, at rest and after E. coli stimulation was increased, as was the attachment and ingestion of yeast particles. The NBT-values were about the same as corresponding values of macrophages lavaged from the lungs of nickel-treated rabbit. Macrophages incubated with surfactant from untreated animals, had NBT values and phagocytic activity similar to cells incubated without surfactant. As this substance was administered in excess, the difference in macrophage response would probably be due to a qualitative alteration of the surfactant after nickel exposure.

Decreased chemotactic and random migration of leukocytes during Intralipid infusion

The soybean oil emulsion Intralipid was given intravenously to 12 healthy subjects for 2 hr. During the infusion an impairment of the chemotactic and random migration of leukocytes was noted. It was correlated to the dose given and to the degree of hypertriglyceridemia induced. Migration was fully restituted 22 hr after the infusion. Also when added in vitro Intralipid caused an impairment of leukocyte motility that followed a dose response pattern.

Alveolar macrophage function in nickel dust exposed rabbits

8 rabbits were exposed to metallic nickel dust (2 mg/m3, of which about half was respirable) for 4 weeks. The lungs were lavaged and the macrophages were collected. In comparison with 8 control rabbits, a significant increase was noted in the nickel exposed rabbits as concerned the weight and density of the lungs, the size variation of the lung cells, the phagocytosis of silver coated particles, and the metabolic activity as measured by NBT reduction. The last mentioned increase was recorded during basal conditions as well as during phagocytosis. The NBT reduction during phagocytosis was significantly correlated with the degree of phagocytosis of silver coated particles in both control and exposed rabbits. It is suggested that the exposure to nickel dust has unspecifically activated the macrophages perhaps by increased production of phospholipids.

The value of immunoelectroosmophoresis (IEOP) for etiological diagnosis of acute respiratory tract infections due to pneumococci and Mycoplasma pneumoniae

Immunoelectroosmophoresis (IEOP) has been used to detect pneumococcal and Mycoplasma pneumoniae antigen in 324 sputum samples from 224 patients. Pneumococcal antigen was found in 30/37 samples from which pneumococci had earlier been isolated and in 72/243 specimens where they had not been found. Of these 72 samples 69 were from patients treated with antibiotics. Mycoplasma antigen was found in 9/57 sputum samples from which Mycoplasma had been isolated and in 2/32 other samples from patients with a serologically verified diagnosis of mycoplasmal infection. As to pneumococci, the IEOP is of value because of its rapidity and especially because antigen findings can be made in patients treated with antibiotics. In spite of sonication and concentration, mycoplasma antigen was too rarely found for the method, as now carried out, to be useful in diagnostic work.