Rapid diagnosis of influenza A and B by 24-h fluorescent focus assays

Murine monoclonal antibodies directed against type-specific antigens of influenza A and B viruses have been shown to be useful diagnostic reagents for the detection of influenza viruses by immunofluorescence testing of nasopharyngeal cells. We have developed fluorescent focus assays utilizing these antibodies in cell culture chamber slides and shell vials for the rapid diagnosis of influenza A and B. Chamber slide assays were compared with virus isolation in 160 specimens from 135 patients with symptoms of influenza. Virus isolation was compared with immunofluorescence testing in 38 of the 160 specimens. Compared with virus isolation, 24-h cell culture chamber slide assays had a sensitivity of 75% and a specificity of 96%. Immunofluorescence testing of nasopharyngeal cells was only 38% sensitive and 91% specific. Shell vial assays were compared with virus isolation for 89 specimens. At 16 to 18 h postinoculation, the shell vial assay was 84% sensitive and 100% specific. We conclude that both chamber slide and shell vial assays are rapid, sensitive, and specific techniques for the diagnosis of influenza.

Recent advances in immunologic reactivity in otitis media with effusion

The role of IgE-mediated hypersensitivity in the development of middle ear disease has not been completely resolved. However, on the basis of our investigations and those of other laboratories, we suggest that approximately two thirds of patients with chronic recurrent otitis media do not have allergies. The other third may have allergic rhinitis, and this allergic rhinitis could play a direct role in producing eustachian tube dysfunction in recurrent otitis media. However, viral infections of the upper respiratory tract may also induce IgE-mediated release of mast cell inflammatory mediators, and could cause otitis media on the basis of viral infection alone. Subtle immunologic deficiencies involving the IgG2 subclass and other immunoglobulin subclasses may also be lower in otitis-prone children, and this may be a genetically inherited disorder. Finally, the possibility of food allergy in otitis media must be considered, particularly in the young otitis-prone child with chronic recurrent otitis media.

Clinical impedance audiometry

This manuscript has attempted to briefly outline the most important areas of clinical impedance audiometry. The author has emphasized the use of impedance audiometry in differentiating different types of middle ear pathology and utilizing the stapedial reflex in the determination of malingering as well as an overall test of the normal function of the auditory nervous system from the inner ear to brain stem. Finally, the use of Eustachian tube function can also be utilized by the trained audiologist in determining whether or not there is Eustachian tube dysfunction. It is important to again emphasize that impedance audiometry is objective and does not involve the cooperation of the patient. Thus in the autistic child and in the child who is uncooperative, it is of particular help to the clinical otologist and audiologist. In patients who are malingering the stapedial reflex may assist in determining a valid response in routine autiometry. Finally, with special types of tests which have not been discussed in this manuscript, such as stapedial reflex decay, one may be able to determine the presence of an early acoustic neurinoma.

The distribution of immunocompetent cells in the compartments of the palatine tonsils in bacterial and viral infections of the upper respiratory tract

Employing a series of monoclonal antibodies directed against T cell subsets using the avidin-biotin complex method as the immunoperoxidase technique and using fluorescein-conjugated antisera directed against the major immunoglobulins, we have studied the distribution of immunocompetent cells in sections of tonsils from 21 patients with various inflammatory diseases of the tonsils, including Streptococcal tonsillitis, recurrent tonsillitis and tonsillitis associated with infectious mononucleosis. The following conclusions can be made in regard to our study. The percentage of T cells decreases in all compartments of the tonsils with increasing episodes of tonsillitis as well as with infectious mononucleosis and Streptococcal tonsillitis. Similarly, the percentage of HLA-DR positive cells decreases with increasing episodes of tonsillitis and is statistically significant in the mantle zone. The percentage of IgM B cells and IgD B cells tends to increase in the extrafollicular zone and decrease in the mantle zone with increasing episodes of tonsillitis as well as with increasing age. The percentage of IgG and IgA plasma cells is highest in children who have had 3-5 episodes of tonsillitis, but markedly decreases in the follicle and extrafollicular compartments in patients who have had more than 5 episodes of tonsillitis. FACS analysis of B cells in the tonsils and peripheral blood show a marked decrease in IgD in both the tonsil and the peripheral blood and a significant increase of IgG in the peripheral blood. These findings may suggest late clonal expansion of B cells in recurrent tonsillitis and Streptococcal tonsillitis. Finally, the distribution of immunocompetent cells in recurrent tonsillitis, Streptococcal tonsillitis and tonsillitis associated with infectious mononucleosis appears to be independent of age.

Outer membrane protein and lipooligosaccharide analysis of paired nasopharyngeal and middle ear isolates in otitis media due to nontypable Haemophilus influenzae: pathogenetic and epidemiological observations

We studied isolates of nontypable Haemophilus influenzae from cultures of nasopharynx and middle ear fluid (MEF) done simultaneously on children with otitis media. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of outer membrane protein (OMP) patterns demonstrated that in 16 of 19 pairs, the nasopharyngeal and MEF strains were identical. With four monoclonal antibodies to lipooligosaccharide (LOS) determinants, 17 of the 19 pairs were identical. Thus the pathogenesis of otitis media due to nontypable H. influenzae appears to involve spread of the bacteria from the nasopharynx to the middle ear. Analysis of middle ear isolates from four children with recurrent otitis media caused by nontypable H. influenzae indicated that the recurrent episodes were caused by reinfection with different strains rather than by persistence of the same strain. OMP and LOS analysis of strains from two sisters with concurrent otitis media suggested that person-to-person transmission of nontypable H. influenzae can occur among children.

Oral ribavirin treatment of influenza A and B

A loading dose and short-term administration of oral ribavirin significantly improved symptoms and signs of influenza type A or B infection in 25 patients. The antiviral effect was not significant. No adverse clinical effects or significant laboratory values were observed. Oral treatment of patients with influenza A or B infection might be possible with ribavirin.

Modulation of monocyte Mo2 surface antigen expression by exposure to respiratory syncytial virus

The Mo2 antibody recognizes a monocyte-specific cell surface antigen of unknown function. Upward modulation of Mo2 surface epitope density was demonstrated in response to 72-hr culture of monocytes with respiratory syncytial virus (RSV), but this was not seen after culture with phytohemagglutinin or other respiratory viruses. Monoclonal antibody probes for RSV proteins were used to demonstrate probable replication of RSV proteins in peripheral blood monocytes and pulmonary alveolar macrophages. These data provide possible clues to the biologic role of the Mo2 antigen.

Comparative sensitivity of 125I-protein A and enzyme-conjugated antibodies for detection of immunoblotted proteins

Immunoblotting is a powerful technique for the detection of small amounts of immunologically interesting proteins in unpurified preparations. Iodinated protein A (PA) has been widely used as a second antibody for detection of proteins; however, it does not bind equally well to immunoglobulins from different species nor does it bind to all subclasses of immunoglobulin G (IgG). We compared the sensitivity of [125I]PA with those of both horseradish peroxidase-conjugated second antibodies (HRP) and glucose oxidase-anti-glucose oxidase (GAG) soluble complexes for visualizing bovine serum albumin, human IgG, or human C3 which was either dot blotted or electroblotted to nitrocellulose. [125I]PA was uniformly 10- to 100-fold less sensitive than either HRP or GAG. GAG was more sensitive than HRP except for C3 (electroblotting) and bovine serum albumin and IgG (dot blotting), in which they were equivalent. In general, dot blotting was 10- to 1,000-fold more sensitive than electroblotting. Although relative sensitivities varied depending on the proteins analyzed and the antisera used, GAG appeared to be superior to [125I]PA and HRP for detection of immunoblotted proteins.

Immune responses to herpes simplex virus in patients with recurrent herpes labialis: I. Development of cell-mediated cytotoxic responses

Groups of subjects during acute (0-3 days) and convalescent (2-3 weeks) phase of recurrent herpes labialis (RHL), and other subjects seropositive or seronegative for herpes simplex virus type 1 (HSV-1) antibody without any history of RHL, were tested for the appearance of cell-mediated cytotoxic responses by stimulating peripheral blood leukocytes (PBL) in vitro with ultraviolet-inactivated HSV-1 antigen, using the release of radiolabelled chromium (51Cr) from HSV-1-infected autologous, or allogeneic lymphocytes and K562 erythroleukemia cell line as nonspecific targets. Development of HSV specific cytotoxic response using autologous targets was essentially limited to subjects with RHL and in HSV antibody seropositive control subjects. Peak activity was observed during the acute phase of the disease, compared to the activity in the convalescent phase in seropositive subjects with RHL, and was preceded by high lymphoproliferative response to HSV. Higher cytotoxic responses against K562 cells were also observed in RHL subjects compared to the controls. Depletion of Leu-2+, Leu-3+ or Leu-11 effector lymphocytes from HSV-1-stimulated PBL cultures by treatment with complement and appropriate monoclonal antibodies resulted in significant reduction of cytotoxicity to HSV-1-infected autologous cells. However, cytotoxicity to K562 cells was reduced only after depletion of Leu-11+ cells. Low levels of allogeneic restriction were observed for cytotoxicity to HSV-1-infected targets. These observations suggest selective activation of virus specific Leu-2+ and Leu-3+ T cell subsets as well as natural killer cell mediated cytotoxic mechanisms during the active phase of recurrences of herpes simplex virus infection.

Relative efficacy and toxicity of netilmicin and tobramycin in oncology patients

We prospectively compared the efficacy and safety of netilmicin sulfate or tobramycin sulfate in conjunction with piperacillin sodium in 118 immunocompromised patients with presumed severe infections. The two treatment regimens were equally efficacious. Nephrotoxicity occurred in a similar proportion in patients treated with netilmicin and tobramycin (17% vs 11%). Ototoxicity occurred in four (9.5%) of 42 netilmicin and piperacillin and in 12 (22%) of 54 tobramycin and piperacillin-treated patients. Of those evaluated with posttherapy audiograms, three of four netilmicin and piperacillin-treated patients had auditory thresholds return to baseline compared with one of nine tobramycin and piperacillin-treated patients. The number of greater than or equal to 15-dB increases in auditory threshold as a proportion of total greater than or equal to 15-dB changes (increases and decreases) was significantly lower in netilmicin and piperacillin- vs tobramycin and piperacillin-treated patients (18 of 78 vs 67 of 115). We conclude that aminoglycoside-associated ototoxicity was less severe and more often reversible with netilmicin than with tobramycin.

Immune response to herpes simplex virus in patients with recurrent herpes labialis. II. Relationship between interferon production and cytotoxic responses

The relationship between the development of cytotoxic cellular immune response to herpes simplex virus type I (HSV-1)-infected autologous cells and the production of interferon (IFN) was studied using in vitro secondary sensitization of peripheral blood leukocytes in subjects with recurrent herpes labialis (RHL) and in normal controls without any history of recurrent herpes labialis. There was a significant discordance between optimal HSV-1 antigen dose required for induction of peak cytotoxic responses and for maximal activity of IFN. Moderate IFN activity (6-100 U/ml) was demonstrated in all HSV-1 antigen-stimulated peripheral blood leukocytes collected from subjects during both acute and convalescent phase of RHL. However, only 50% of seropositive controls and no seronegative controls exhibited detectable IFN activity, when stimulated with HSV-1 antigen, although such in vitro stimulation resulted in maximal virus-specific cell-mediated cytotoxicity. A correlation of virus specific cytotoxic activity to HSV-1 and IFN production (r = 0.38, p less than 0.05) was less marked than that of cytotoxic activity to K562 (natural killer-sensitive target cells) and IFN titer (r = 0.48, p less than 0.01). Furthermore significant reverse correlations between cytotoxicity against HSV-1-infected autologous cells and a titer of gamma-IFN was observed in samples with high cytotoxic activity. These observations suggest that gamma-IFN produced by HSV immune T cell may also act as an autoregulatory factor against the production of cytotoxic cellular activity against HSV-1-infected autologous cells.

The effect of biliary obstruction on a gram-negative bacteremic challenge: a preliminary report

Alterations in the sequestration and destruction of bacteria were studied after 10 days of biliary obstruction. Intraperitoneal injection of radiolabeled Escherichia coli was used to study bacterial localization in rats 10 days after common duct ligation and transection or sham celiotomy. Animals were sacrificed 4 hours later and uptake by liver, spleen, lung, and kidney were studied with a scintillation counter. No significant difference in localization between the two groups was noted. Bacteremia was induced in a second set of animals and quantitative bacterial organ cultures were performed. Significantly more viable organisms were identified in lung, liver, and kidney of animals that underwent common duct ligation and transection, when compared with controls that underwent sham celiotomy. This suggests that there is a defect in bacterial killing after 10 days of biliary obstruction. The inability to effectively clear and kill gram-negative bacteria in patients with biliary obstruction may account for some of the clinical complications seen in this patient population.

Defective immunoregulation in children with chronic otitis media with effusion

Otitis media and middle ear effusions (MEE) are most common clinical problems in early childhood, for which an estimated one million tympanostomies are performed each year in the United States. Although many factors have been associated with MEE (age, sex, genetics, otitis media, socioeconomic status, feeding style, atopy or hypersensitivity, certain bacteria and viruses), a defective immunoregulatory mechanism in the host may also contribute to the pathogenesis. During the past 2 years, we have evaluated immune function in 90 randomly selected children who underwent repeated tympanostomy for persistent MEE. The T-cell subset ratio (OKT-4/OKT-8) was reduced (below 1.25) in 16%. In 33 children, generation of T-cell growth factor (IL-2) by peripheral blood lymphocytes (PBL) was evaluated and found to be decreased in 11. The mitogenic response of PBL to phytohemagglutinin (PHA) and pokeweed mitogen (PWM) stimulation was abnormal in almost half of the cases. Imbalance of T-cell subsets and decreased production of IL-2 indicate defective immunoregulatory function in some of these children, which may play a role in the pathogenesis of persistent MEE.

Recent advances in otitis media with effusion

OME is similar to other chronic inflammatory diseases with the additional fact that ventilation of the middle ear is an extremely important and necessary part of therapy. Antimicrobial therapy alone may not cure middle ear inflammatory disease as long as Eustachian tube dysfunction persists. If Eustachian tube dysfunction and middle ear fluid persists, all forms of immunologic reactivity may occur in the middle ear which may result in persistent effusion and damage to the mucosal system, to the middle ear ossicles, and to the mastoid mucosal system. These changes may require more aggressive surgical management. It is obvious that we must learn more about the physiology and pathophysiology of the Eustachian tube; about understanding of the systemic, and particularly the local humoral and cell-mediated immune response in the middle ear. Finally, we must determine the potential role of inflammatory mediators, both in the protection against disease and also in the potential role that they play in tissue injury. Encouraging progress is being made in all of these areas and it seems likely that the increased research interest and productivity from laboratories throughout the world will eventually lead to the goal of enhanced prevention and improved treatment of OME.

Infectivity of vascular sutures

Bacterial adherence to vascular sutures was evaluated in vitro using radioactively labeled Staphylococcus aureus. The following suture materials were tested: polypropylene, silicone-treated braided polyester, and Teflon-treated braided polyester. Significantly fewer bacteria adhered to the monofilament polypropylene than either of the braided polyester sutures. There was no significant difference between silicone-treated and Teflon-treated polyester from the standpoint of bacterial adherence. Vascular sutures were evaluated in vivo using a mouse wound model. Sutures were tested with and without knots. When tested without knots, fewer bacteria were recovered from wounds containing polypropylene suture compared to either of the braided materials, although this apparent advantage did not prove to be statistically significant. When studied with knots, the differences among types of suture were much less marked and, again, not significant. The purported contribution of the monofilament structure of a suture to its infection resistance may have been overstated.

Further observations on the role of IgE-mediated hypersensitivity in recurrent otitis media with effusion

One hundred young patients with recurrent otitis media with effusion (OME) were evaluated for IgE-mediated hypersensitivity by critical analysis of history, physical findings, skin testing for selected antigen, laboratory determination of total IgE, and radioallergosorbent testing (RAST) for six inhalant and two food allergens. The patients could be divided into allergic rhinitis and nonallergic groups. Allergic rhinitis patients had higher total IgE in their serum, and middle ear effusion (MEE). IgE was elevated in 16 of 35 allergic patients. In 8 of these 16 (23% of the allergic group), the IgE/mg protein was higher in the MEE than in the corresponding serum, suggesting local production of IgE. Nasal IgE was substantially increased in the allergic patients; however, in many patients there was no correlation between the corresponding MEE IgE and elevated nasal IgE, suggesting that local production of nasal and middle ear IgE is independent. We conclude that IgE-mediated allergic reactions may play a role in the pathogenesis of OME in about 23% of young allergic patients.

Fatal coxsackievirus B4 infection in a neonate

We reported a fatal coxsackievirus B4 infection in a neonate. The CSF WBC was elevated, with polymorphonuclear leukocytes predominating initially and lymphocytes predominating later in the illness. Autopsy findings included inflammation of the heart and liver. Coxsackievirus B4 was isolated from the heart and quantitated as 10(3) 50% tissue culture infectious doses (TCID50) per gram of myocardium.

The middle ear mucosal immune system in otitis media with effusion

The mucous membrane of the middle ear cavity in otitis media with effusion has a number of immunobiological mechanisms capable of defending the organ. A humoral immune mechanism, with all the attributes of a local mucosal immune system, appears to be present and capable of preventing viral and bacterial access to middle ear tissue. Putative cells of a cell-mediated immune response also appear to be present, and the distribution of T cells and B cells and T-helper and T-suppressor cells is described. The exact role of these cells in either cell-mediated immunity or delayed hypersensitivity remains to be defined in otitis media. Lymphocyte--macrophage interaction is briefly described and may represent an important aspect of immune modulation in the middle ear in otitis media with effusion. Finally, the effect of middle ear supernatants on natural killer cell activity is discussed. Serous effusions appear to augment natural killer cell activity of peripheral blood lymphocytes.

Oxygen consumption of middle ear and peripheral blood neutrophils in acute suppurative otitis media

Using an oxygen electrode, oxygen consumption has been measured in peripheral blood neutrophils and the corresponding middle ear fluid neutrophils of 26 patients with acute suppurative otitis media. The data suggest that the middle ear fluid neutrophil is functional and is capable of producing an adequate oxygen burst in response to membrane stimulation by opsonized zymosan particles. Some middle ear neutrophils are actually capable of producing a greater respiratory burst than their counterparts in the peripheral blood. However, middle ear neutrophils do not show the increased metabolic activity at 40 degrees C, which blood neutrophils regularly displayed compared with tests performed at 37 degrees C. It is believed that this temperature (40 degrees C) is more physiological during infection and might explain why middle ear neutrophils may not always be capable of destroying bacteria, even though they are present in adequate numbers in the middle ear fluid in some cases of acute suppurative otitis media. Further studies are needed to determine the nature of the defect(s) present in middle ear neutrophil at 40 degrees C.

Observations on immune mechanisms in otitis media with effusion

In this brief review of recent advances in immunological reactivity in otitis media, I have neither attempted to review the field from a historical perspective, nor attempted a critical analysis of the current status and future frontiers of this area. I have, rather, reviewed 5 areas that are being pursued in our laboratory and compare our investigations with those being performed throughout the country and abroad. It is my sincere hope that investigations into these areas will continue and will lead to potentially fruitful and meaningful data that will eventually unravel the mystery of persistent OME.