Mononuclear Cells From Human Lung Parenchyma Support Antigen‐Induced T Lymphocyte Proliferation

We have previously demonstrated that there is a subpopulation of loosely adherent pulmonary mononuclear cells that can be isolated from minced and enzyme‐digested lung tissue with a potent capacity to stimulate allogeneic T lymphocyte proliferation. We now demonstrate that these cells are also capable of stimulating an autologous mixed leukocyte reaction (AMLR) and presenting antigen to autologous T lymphocytes. These loosely adherent mononuclear cells (LAM) were more effective than either alveolar macrophages or monocytes as antigen‐presenting cells. Depletion of phagocytic or Fc receptor‐positive cells from the LAM population enhanced the stimulation of an reaction AMLR while preserving antigen‐induced T lymphocyte proliferation. These results indicate that there are nonphagocytic, Fc receptor‐negative accessory cells in human lung parenchyma capable of activating resting T cells in an AMLR and supporting antigen‐specific T lymphocyte proliferation. The identity of these cells is uncertain, but the data strongly suggest that the cell is not a classical monocyte‐derived macrophage. These antigen‐presenting cells may be critical in the initiation of immune responses within the lung.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141257/1/jlb0336.pd

Separation of Potent and Poorly Functional Human Lung Accessory Cells Based on Autofluorescence

Human alveolar macrophages obtained by bronchoalveolar lavage are usually poor accessory cells in in vitro lymphoprollferation assays. However, we recently described a subpopulation of pulmonary mononuclear cells, obtained from minced and enzyme‐digested lung, which were potent stimulators of allogeneic T‐lymphocyte proliferation. These cells were enriched in loosely adherent mononuclear cell (LAM) fractions, but further study of these accessory cells was hampered by the heterogeneous nature of LAM. It was observed that in the majority of lung tissue sections, most alveolar macrophages were autofluorescent, whereas most interstitial HLA‐DR positive cells were not. Therefore autofluorescence was utilized to fractionate LAM in an attempt to remove alveolar macrophages and selectively purify interstitial accessory cells. LAM were separated by flow cytometry using forward and side scatter to exclude lymphocytes, and red autofluorescence to obtain brightly autofluorescent (A pos) and relatively nonautofluorescent (A neg) mononuclear cells. Although both populations contained over 80% HLA‐DR positive cells, A pos cells were poor accessory cells, whereas A neg cells were extremely potent stimulators of a mixed leukocyte reaction at all stimulator ratios tested. When A pos cells were added to A neg cells, T‐cell proliferation was markedly suppressed in the majority of experiments. Morphologically, A pos cells appeared similar to classical alveolar macrophages with 95% of the cells being large and intensely nonspecific esterase positive. In contrast, the majority of A neg were smaller, B‐cell antigen‐negative, nonspecific esterase negative, and had a distinctive morphology on Wright‐stained smears. We conclude that fractionation of LAM based on autofluorescence is a powerful tool to isolate and characterize lung mononuclear cells that act either as stimulators or as suppressors of immune responses in the lung.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141667/1/jlb0458.pd

Far ultraviolet response of silicon P-N JUNCTION photodiodes

Silicon P-N junction photodiode resistivity in vacuum ultraviole

A note on maximal estimates for stochastic convolutions

In stochastic partial differential equations it is important to have pathwise regularity properties of stochastic convolutions. In this note we present a new sufficient condition for the pathwise continuity of stochastic convolutions in Banach spaces.Comment: Minor correction

Colorado Native Plant Society Newsletter, Vol. 9 No. 1, January-February 1984

The Colorado Native Plant Society Newsletter will be published on a bimonthly basis. The contents will consist primarily of a calendar of events, notes of interest, editorials, listings of new members and conservation news. Until there is a Society journal, the Newsletter will include short articles also. The deadline for the Newsletter is one month prior to its release.https://epublications.regis.edu/aquilegia/1023/thumbnail.jp

Previous tonsillectomy modifies odds of tonsil and base of tongue cancer

BACKGROUND: Tonsillectomy is a commonly performed surgical procedure that involves removal of the palatine tonsils. The purpose of this study is to examine the association between previous tonsillectomy and odds of oropharyngeal squamous cell carcinoma (OPSCC) in a large population-based case-control study. We hypothesise that previous tonsillectomy is associated with a decreased odds of tonsil cancer with no impact on the odds of developing base of tongue (BOT) cancer. METHODS: This was a population-based, frequency-matched case-control study with multinomial logistic regression, including 1378 controls, 108 BOT cancer cases, and 198 tonsil cancer cases. Demographic and risk factor data were collected using a structured questionnaire during an in-home visit conducted by trained nurse-interviewers. The human papillomavirus (HPV) tumour status was determined through Luminex-based multiplex PCR and p16 status by immunohistochemistry. RESULTS: Previous tonsillectomy was associated with a nearly two-fold increased odds of BOT cancer (OR=1.95, 95% CI 1.25-3.06, P=0.003) and a large decrease in the odds of tonsil cancer (OR=0.22, 95% CI 0.13-0.36, P<0.001). When HPV status was considered, tonsillectomy was associated with a decreased odds of HPV-positive tonsil cancer (OR=0.17, 95% CI 0.08-0.34, P<0.001) and an increased risk of HPV-positive BOT cancer (OR=2.46, 95% CI 1.22-4.95, P=0.012). When p16 status was considered, tonsillectomy was associated with an increased odds of p16-positive BOT cancer (OR=2.24, 95% CI 1.16-4.35, P=0.017) and a decreased odds of p16-positive tonsil cancer (OR=0.14, 95% CI 0.07-0.31, P<0.001). CONCLUSIONS: Previous tonsillectomy modifies the odds of both tonsil and BOT cancer, with decreased odds of tonsil cancer and increased odds of BOT cancer. A history of previous tonsillectomy may play a role in OPSCC risk stratification when considered along with other covariates such as sexual history, smoking status, and age

Racial differences in the relationship between tobacco, alcohol, and squamous cell carcinoma of the head and neck

Tobacco and alcohol use are well-known risk factors for squamous cell carcinoma of the head and neck (SCCHN), but there has been little examination of disparities in SCCHN and racial patterns of tobacco and alcohol use, especially for African-Americans. The Carolina Head and Neck Cancer Study, a population-based case-control study, was utilized to determine if relationships between tobacco and alcohol use and SCCHN differed by race

Body mass index and risk of head and neck cancer by race: the Carolina Head and Neck Cancer Epidemiology Study

Most studies, primarily conducted in populations of European ancestry, reported increased risk of head and neck cancer (HNC) associated with leanness (body mass index (BMI) 30 kg/m2, respectively), compared to normal weight (18.5-<25.0 kg/m2)