Lymphopenia with Altered T Cell Subsets in Hospitalized COVID-19 Patients in Pune, India

The cellular immune cell subsets affecting COVID-19 disease severity are being studied by researchers from many countries. The current study was carried out to investigate the alteration of peripheral blood mononuclear cells (PBMCs) and their subsets in hospitalized COVID-19 patients in a tertiary care center in Pune, India. The PBMCs were isolated from enrolled study participants, and flow cytometry analysis was done to assess peripheral white blood cell alterations. The lymphocyte subsets of naive, effector, central memory, and effector memory CD4+ or CD8+ T cells were then evaluated in COVID-19 patients with different disease categories and compared to healthy controls. The immunophenotypic characterization of the immune cell subset was done for 139 COVID-19 patients and 21 healthy controls. These data were evaluated based on the disease severity. A total of 139 COVID-19 patients were classified as mild (n = 30), moderate (n = 57), or severe (n = 52) cases. The decreased percentages of total lymphocytes, CD3+ T cells, CD4+ T cells, naive T cells, central memory T cells, and Natural Killer (NK) cytotoxic cells were found, and there was increase in effector T (TEf) cells and effector memory T cells in patients with severe COVID-19 compared to healthy controls. The severity of SARS-CoV-2 infection has an effect on lymphocyte subsets, resulting in reduced T memory cells and NK cells but increased TEf cells in severe cases. Clinical Trial Registration: CTRI ID-CTRI/2021/03/032028.

Peripheral lymphocyte subset alteration in patients with COVID-19 having differential clinical manifestations

Background & objectives:

The COVID-19 disease profile in Indian patients has been found to be different from the Western world. Changes in lymphocyte compartment have been correlated with disease course, illness severity and clinical outcome. This study was aimed to assess the peripheral lymphocyte phenotype and subset distribution in patients with COVID-19 disease from India with differential clinical manifestations.

Methods:

Percentages of peripheral lymphocyte subsets were measured by flow cytometry in hospitalized asymptomatic (n=53), mild symptomatic (n=36), moderate and severe (n=30) patients with SARS-CoV-2 infection, recovered individuals (n=40) and uninfected controls (n=56) from Pune, Maharashtra, India.

Results:

Percentages of CD4+Th cells were significantly high in asymptomatic, mild symptomatic, moderate and severe patients and recovered individuals compared to controls. Percentages of Th memory (CD3+CD4+CD45RO+), Tc memory (CD3+CD8+CD45RO+) and B memory (CD19+CD27+) cells were significantly higher in the recovered group compared to both asymptomatic, mild symptomatic patient and uninfected control groups. NK cell (CD56+CD3-) percentages were comparable among moderate +severe patient and uninfected control groups.

Interpretation & conclusions:

The observed lower CD4+Th cells in moderate+severe group requiring oxygen support compared to asymptomatic+mild symptomatic group not requiring oxygen support could be indicative of poor prognosis. Higher Th memory, Tc memory and B memory cells in the recovered group compared to mild symptomatic patient groups might be markers of recovery from mild infection; however, it remains to be established if the persistence of any of these cells could be considered as a correlate of protection.

Occupational dermatitis related to chromium and cobalt: experience of dermatologists (EPIDERM) and occupational physicians (OPRA) in the U.K. over an 11-year period (1993-2004)

BACKGROUND

Chromium and cobalt (and their compounds) are well recognized as being important causes of occupational contact dermatitis (OCD), particularly of the hands, although their exact contribution to occupational hand dermatitis varies between different studies. In some European studies, cases of chromium-related dermatitis have decreased following the addition of ferrous sulphate to cement to reduce the amount of available chromium.

OBJECTIVES

To examine, using data from the U.K. occupational skin surveillance schemes, the proportionate reported incidence and changing trends in OCD considered to be related to chromium and cobalt for the 11-year period from February 1993 to December 2004.

METHODS

Surveillance data collected by the two British occupational health surveillance schemes, EPIDERM and OPRA, from February 1993 to December 2004 were studied. These are occupational health surveillance schemes in the U.K. to which physicians voluntarily and anonymously report new cases of skin disease suspected to be work related.

RESULTS

Over the 11-year period, dermatologists reported 22 184 cases of OCD, comprising 77% of all types of occupational skin diseases that were disclosed. Chromium was recorded as being thought to play a role in 1226 (6%) of these, with cobalt identified as being likely to be implicated in 823 (4%). The numbers fluctuated on a year-on-year basis but there were no overall trends during the period of study. The male/female ratio was 5 : 1 for chromium and 1 : 1 for cobalt. Overall, the male/female ratio for OCD was 1.4 : 1. The rates of dermatitis believed to be related to both metals generally increased with age. In women, the highest rate for chromium was seen in the > 60 years age group, whereas conversely, for cobalt the rate decreased with age. For chromium-related OCD the most common occupations were builders and building contractors, bricklayers, construction workers and plasterers. For cobalt-related OCD, the commonest occupations were hairdressers/barbers, builders/building contractors, retail cash/checkout operators, machine operatives and domestic cleaners. Occupational physicians reported 15 016 cases of OCD (82% of all occupational skin diseases reported by them) for the period May 1994-December 2004. Of these, only 38 cases were thought to be related to chromium and 30 to cobalt (25 of the latter were processing labourers).

CONCLUSIONS

In this series, chromium was reported by dermatologists as potentially being involved in 6% of all cases of OCD in the U.K., and cobalt in 4%. Our data support the view that chromium-related dermatitis has an onset in later working life and often affects those in the building trades, whereas cobalt-related dermatitis seems to have an earlier onset and may affect a wide range of employments.